[RFC PATCH] mmc: mmci: Add qcom dml support to the driver.

[Srinivas Kandagatla]

On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.

Most of this code has been ported from qualcomm's 3.4 kernel.

This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Signed-off-by: Srinivas Kandagatla <***@linaro.org>
---

Hi All,

DMA support for Qualcomm SD card controller is missing in my last patchset, the
reason to post this patch separately is because of the unusual glue logic
between card controller and the dma-controller. This glue logic is called DML
(Data mover local/lite).

DML assists dma transfers between sd card controller and dma-controller. As this
DML gule is part of SD controller IP and needs configuring for every transfer,
So I thought of keeping it close to driver in drivers/mmc/ directory is more
usefull, than trying to find a infrastructure to fit it. DML itself is not a DMA
controller but an logic present on SD card controller and it resides in SD card
controller IP.

I would like to get your opnion on overall correctness of the approch.

Thanks in advance.
srini


drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/qcom_dml.c | 171 ++++++++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/qcom_dml.h | 17 +++++
5 files changed, 218 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/qcom_dml.c
create mode 100644 drivers/mmc/host/qcom_dml.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..f50ccbb 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI

If unsure, say N.

+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && ARCH_QCOM
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..e6a14ac 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#

obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..c537296 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>

#include "mmci.h"
+#include "qcom_dml.h"

#define DRIVER_NAME "mmci-pl18x"

@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
* @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply
* @explicit_mclk_control: enable explicit mclk control in driver.
* @qcom_fifo: enables qcom specific fifo pio read logic.
+ * @qcom_dml: enables qcom specific dml glue for dma transfers.
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};

static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};

static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;

host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,11 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel) {
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
+ }
}

/*
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ u32 flags = DMA_CTRL_ACK;

if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;

+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;

@@ -644,6 +658,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);

+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;

/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/qcom_dml.c b/drivers/mmc/host/qcom_dml.c
new file mode 100644
index 0000000..e2ecd07
--- /dev/null
+++ b/drivers/mmc/host/qcom_dml.c
@@ -0,0 +1,171 @@
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *dml_base;
+
+ dml_base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+
+ /* Set the Producer BAM block size */
+ writel(data->blksz, (dml_base + DML_PRODUCER_BAM_BLOCK_SIZE));
+
+ /* Set Producer BAM Transaction size */
+ writel(data->blocks * data->blksz,
+ (dml_base + DML_PRODUCER_BAM_TRANS_SIZE));
+ /* Set Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG) |
+ PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));
+ /* Trigger producer */
+ writel(1, (dml_base + DML_PRODUCER_START));
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+ /* Clear Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG)
+ & ~PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));
+ /* Trigger consumer */
+ writel(1, (dml_base + DML_CONSUMER_START));
+ }
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int count, i;
+ const char *s;
+ struct of_phandle_args dma_spec;
+
+ if (!np || !name)
+ return -ENODEV;
+
+ count = of_property_count_strings(np, "dma-names");
+ if (count < 0)
+ return -ENODEV;
+
+ for (i = 0; i < count; i++) {
+
+ if (of_property_read_string_index(np, "dma-names", i, &s))
+ continue;
+
+ if (strcmp(name, s))
+ continue;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", i,
+ &dma_spec))
+ continue;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+ }
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config = 0;
+ void __iomem *dml_base;
+ u32 consumer_id = 0, producer_id = 0;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (IS_ERR_VALUE(producer_id) || IS_ERR_VALUE(consumer_id))
+ return -ENODEV;
+
+ dml_base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel(1, (dml_base + DML_SW_RESET));
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel(config, (dml_base + DML_CONFIG));
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel(PRODUCER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_PRODUCER_PIPE_LOGICAL_SIZE));
+ writel(CONSUMER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_CONSUMER_PIPE_LOGICAL_SIZE));
+
+ /* Initialize Producer/consumer pipe id */
+ writel(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ (dml_base + DML_PIPE_ID));
+
+ return 0;
+}
diff --git a/drivers/mmc/host/qcom_dml.h b/drivers/mmc/host/qcom_dml.h
new file mode 100644
index 0000000..d2c5aa45
--- /dev/null
+++ b/drivers/mmc/host/qcom_dml.h
@@ -0,0 +1,17 @@
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

[Linus Walleij]

On Fri, Jul 11, 2014 at 1:48 PM, Srinivas Kandagatla

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Pretty cool :-)

Post by Srinivas Kandagatla
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/qcom_dml.c | 171 ++++++++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/qcom_dml.h | 17 +++++

Please call this file mmci-qcom-dml.c/h so we know that these files
have a strong
dependence.

Post by Srinivas Kandagatla
+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && ARCH_QCOM

The way I get it is that this only makes sense when the qualcomm
DMA engine is used so should it not be

depends on MMC_ARMMMCI && QCOM_BAM_DMA

?

Or maybe we should be less specific?

depends on MMC_ARMMMCI && DMA_ENGINE

?

Post by Srinivas Kandagatla
/*
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ u32 flags = DMA_CTRL_ACK;
if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;
+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;

Is this correct? That augments every incoming DMA request to try to
do an interrupt callback. Why is that necessary? The interrupt
callback still isn't registered, so this isn't used for anything?

If it's still needed it would be a bug in the DMA engine I think.

Yours,
Linus Walleij
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[Srinivas Kandagatla]

Post by Linus Walleij
On Fri, Jul 11, 2014 at 1:48 PM, Srinivas Kandagatla

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Pretty cool :-)

Post by Srinivas Kandagatla
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/qcom_dml.c | 171 ++++++++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/qcom_dml.h | 17 +++++

Please call this file mmci-qcom-dml.c/h so we know that these files
have a strong
dependence.

Post by Srinivas Kandagatla
+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && ARCH_QCOM

The way I get it is that this only makes sense when the qualcomm
DMA engine is used so should it not be
depends on MMC_ARMMMCI && QCOM_BAM_DMA

You are right, making it
depends on MMC_ARMMMCI && QCOM_BAM_DMA
makes more sense.
I will fix this in next version.

Post by Linus Walleij
?
Or maybe we should be less specific?
depends on MMC_ARMMMCI && DMA_ENGINE
?

Post by Srinivas Kandagatla
/*
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ u32 flags = DMA_CTRL_ACK;
if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;
+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;

Is this correct? That augments every incoming DMA request to try to
do an interrupt callback. Why is that necessary? The interrupt
callback still isn't registered, so this isn't used for anything?

There is a special signalling going on between the DMA controller and
IP, whose state machine is controlled by EOT (End of Transfer)
interrupt. This special EOT flag is mapped to DMA_PREP_INTERRUPT in BAM
DMA engine.

The EOT flag requests that the peripheral assert an end of transaction
interrupt when that descriptor is complete. It also results in special
signaling protocol that is used between the attached peripheral and the
core using the DMA controller.

Recently Andy submitted a patch for this:
http://www.gossamer-threads.com/lists/linux/kernel/1935019

Added Andy to the loop as well.


thanks,
srini

Post by Linus Walleij
If it's still needed it would be a bug in the DMA engine I think.
Yours,
Linus Walleij

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[Prakash Burla]

tested-by: Prakash Burla <***@smartplayin.com>
This driver is tested on IFC6410.

Date: Fri, Jul 11, 2014 at 5:18 PM
Subject: [RFC PATCH] mmc: mmci: Add qcom dml support to the driver.
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.
---
Hi All,
DMA support for Qualcomm SD card controller is missing in my last patchset, the
reason to post this patch separately is because of the unusual glue logic
between card controller and the dma-controller. This glue logic is called DML
(Data mover local/lite).
DML assists dma transfers between sd card controller and dma-controller. As this
DML gule is part of SD controller IP and needs configuring for every transfer,
So I thought of keeping it close to driver in drivers/mmc/ directory is more
usefull, than trying to find a infrastructure to fit it. DML itself is not a DMA
controller but an logic present on SD card controller and it resides in SD card
controller IP.
I would like to get your opnion on overall correctness of the approch.
Thanks in advance.
srini
drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/qcom_dml.c | 171 ++++++++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/qcom_dml.h | 17 +++++
5 files changed, 218 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/qcom_dml.c
create mode 100644 drivers/mmc/host/qcom_dml.h

.
[SNIP]
.

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[Srinivas Kandagatla]

On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.

Most of this code has been ported from qualcomm's 3.4 kernel.

This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Tested-by: Prakash Burla <***@smartplayin.com>
Signed-off-by: Srinivas Kandagatla <***@linaro.org>
---
drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/mmci_qcom_dml.c | 171 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 17 ++++
5 files changed, 218 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..3d9b84d 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI

If unsure, say N.

+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && QCOM_BAM_DMA
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..344c870 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#

obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..a83b7b5 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>

#include "mmci.h"
+#include "mmci_qcom_dml.h"

#define DRIVER_NAME "mmci-pl18x"

@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
* @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply
* @explicit_mclk_control: enable explicit mclk control in driver.
* @qcom_fifo: enables qcom specific fifo pio read logic.
+ * @qcom_dml: enables qcom specific dml glue for dma transfers.
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};

static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};

static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;

host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,11 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel) {
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
+ }
}

/*
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ u32 flags = DMA_CTRL_ACK;

if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;

+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;

@@ -644,6 +658,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);

+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;

/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..e2ecd07
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,171 @@
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *dml_base;
+
+ dml_base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+
+ /* Set the Producer BAM block size */
+ writel(data->blksz, (dml_base + DML_PRODUCER_BAM_BLOCK_SIZE));
+
+ /* Set Producer BAM Transaction size */
+ writel(data->blocks * data->blksz,
+ (dml_base + DML_PRODUCER_BAM_TRANS_SIZE));
+ /* Set Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG) |
+ PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));
+ /* Trigger producer */
+ writel(1, (dml_base + DML_PRODUCER_START));
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+ /* Clear Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG)
+ & ~PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));
+ /* Trigger consumer */
+ writel(1, (dml_base + DML_CONSUMER_START));
+ }
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int count, i;
+ const char *s;
+ struct of_phandle_args dma_spec;
+
+ if (!np || !name)
+ return -ENODEV;
+
+ count = of_property_count_strings(np, "dma-names");
+ if (count < 0)
+ return -ENODEV;
+
+ for (i = 0; i < count; i++) {
+
+ if (of_property_read_string_index(np, "dma-names", i, &s))
+ continue;
+
+ if (strcmp(name, s))
+ continue;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", i,
+ &dma_spec))
+ continue;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+ }
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config = 0;
+ void __iomem *dml_base;
+ u32 consumer_id = 0, producer_id = 0;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (IS_ERR_VALUE(producer_id) || IS_ERR_VALUE(consumer_id))
+ return -ENODEV;
+
+ dml_base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel(1, (dml_base + DML_SW_RESET));
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel(config, (dml_base + DML_CONFIG));
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel(PRODUCER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_PRODUCER_PIPE_LOGICAL_SIZE));
+ writel(CONSUMER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_CONSUMER_PIPE_LOGICAL_SIZE));
+
+ /* Initialize Producer/consumer pipe id */
+ writel(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ (dml_base + DML_PIPE_ID));
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..d2c5aa45
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,17 @@
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

[Srinivas Kandagatla]

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.
---

Here is the change log which I forgot in the original patch

Changes since RFC:
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W

Post by Srinivas Kandagatla
drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/mmci_qcom_dml.c | 171 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 17 ++++
5 files changed, 218 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h

thanks,
srini
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[Stephen Boyd]

Post by Srinivas Kandagatla
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..a83b7b5 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;

Maybe s/dml glue/dma glue/ in the comment so we don't refer to the
variable with dml in the name by dml.

Post by Srinivas Kandagatla
*/
struct variant_data {
unsigned int clkreg;
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ u32 flags = DMA_CTRL_ACK;

unsigned long to match function signature please.

Post by Srinivas Kandagatla
if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;
+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..e2ecd07
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,171 @@

No license text? I'd think most of this code is from qualcomm's kernel
and those files all have the gpl stuff.

Post by Srinivas Kandagatla
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *dml_base;
+
+ dml_base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+
+ /* Set the Producer BAM block size */
+ writel(data->blksz, (dml_base + DML_PRODUCER_BAM_BLOCK_SIZE));
+
+ /* Set Producer BAM Transaction size */
+ writel(data->blocks * data->blksz,
+ (dml_base + DML_PRODUCER_BAM_TRANS_SIZE));
+ /* Set Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG) |
+ PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));

Please use local variables instead of writel(readl()). It makes things
much more readable.

Post by Srinivas Kandagatla
+ /* Trigger producer */
+ writel(1, (dml_base + DML_PRODUCER_START));
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+ /* Clear Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG)
+ & ~PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));
+ /* Trigger consumer */
+ writel(1, (dml_base + DML_CONSUMER_START));

It would be better to use the relaxed accessors when possible.

Post by Srinivas Kandagatla
+ }
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int count, i;
+ const char *s;
+ struct of_phandle_args dma_spec;
+
+ if (!np || !name)

Looks unnecessary. name is definitely not NULL because this function is
static and the only caller is right down there. np is most likely not
NULL either, but if it is we should blow up with an oops instead of
silently failing.

Post by Srinivas Kandagatla
+ return -ENODEV;
+
+ count = of_property_count_strings(np, "dma-names");
+ if (count < 0)
+ return -ENODEV;
+
+ for (i = 0; i < count; i++) {
+
+ if (of_property_read_string_index(np, "dma-names", i, &s))
+ continue;
+
+ if (strcmp(name, s))
+ continue;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", i,
+ &dma_spec))
+ continue;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+ }

Could this be rewritten to use of_property_match_string()?

index = of_property_match_string(np, "dma-names", s);
if (index < 0)
return index;

if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
&dma_spec))
return -ENODEV;

Post by Srinivas Kandagatla
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config = 0;

unnecessary initialization.

Post by Srinivas Kandagatla
+ void __iomem *dml_base;
+ u32 consumer_id = 0, producer_id = 0;

unnecessary initialization.

Post by Srinivas Kandagatla
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (IS_ERR_VALUE(producer_id) || IS_ERR_VALUE(consumer_id))

Is it actually possible for these ids to be very large values? Why not
just <= 0?

Post by Srinivas Kandagatla
+ return -ENODEV;
+
+ dml_base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel(1, (dml_base + DML_SW_RESET));
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel(config, (dml_base + DML_CONFIG));

unnecessary parens (throughout this file actually).

Post by Srinivas Kandagatla
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel(PRODUCER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_PRODUCER_PIPE_LOGICAL_SIZE));
+ writel(CONSUMER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_CONSUMER_PIPE_LOGICAL_SIZE));
+
+ /* Initialize Producer/consumer pipe id */
+ writel(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ (dml_base + DML_PIPE_ID));
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..d2c5aa45
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,17 @@

ditto for license text.

Post by Srinivas Kandagatla
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

[Srinivas Kandagatla]

Thanks Stephen for the comments.

Post by Stephen Boyd

Post by Srinivas Kandagatla
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..a83b7b5 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;

Maybe s/dml glue/dma glue/ in the comment so we don't refer to the
variable with dml in the name by dml.

Will fix it in v2.

Post by Stephen Boyd

Post by Srinivas Kandagatla
*/
struct variant_data {
unsigned int clkreg;
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ u32 flags = DMA_CTRL_ACK;

unsigned long to match function signature please.

Ok.

Post by Stephen Boyd

Post by Srinivas Kandagatla
if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;
+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..e2ecd07
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,171 @@

No license text? I'd think most of this code is from qualcomm's kernel
and those files all have the gpl stuff.

Thanks for spotting, I will copy paste the text from 3.4 kernel.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+ void __iomem *dml_base;
+
+ dml_base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+
+ /* Set the Producer BAM block size */
+ writel(data->blksz, (dml_base + DML_PRODUCER_BAM_BLOCK_SIZE));
+
+ /* Set Producer BAM Transaction size */
+ writel(data->blocks * data->blksz,
+ (dml_base + DML_PRODUCER_BAM_TRANS_SIZE));
+ /* Set Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG) |
+ PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));

Please use local variables instead of writel(readl()). It makes things
much more readable.

OK, will be fixed in v2.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+ /* Trigger producer */
+ writel(1, (dml_base + DML_PRODUCER_START));
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl(dml_base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel(config, (dml_base + DML_CONFIG));
+ /* Clear Producer Transaction End bit */
+ writel((readl_relaxed(dml_base + DML_CONFIG)
+ & ~PRODUCER_TRANS_END_EN),
+ (dml_base + DML_CONFIG));
+ /* Trigger consumer */
+ writel(1, (dml_base + DML_CONSUMER_START));

It would be better to use the relaxed accessors when possible.

Ok, I will use it.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+ }
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int count, i;
+ const char *s;
+ struct of_phandle_args dma_spec;
+
+ if (!np || !name)

Looks unnecessary. name is definitely not NULL because this function is
static and the only caller is right down there. np is most likely not
NULL either, but if it is we should blow up with an oops instead of
silently failing.

I agree its an over do. Will fix it.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+ return -ENODEV;
+
+ count = of_property_count_strings(np, "dma-names");
+ if (count < 0)
+ return -ENODEV;
+
+ for (i = 0; i < count; i++) {
+
+ if (of_property_read_string_index(np, "dma-names", i, &s))
+ continue;
+
+ if (strcmp(name, s))
+ continue;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", i,
+ &dma_spec))
+ continue;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+ }

Could this be rewritten to use of_property_match_string()?
index = of_property_match_string(np, "dma-names", s);
if (index < 0)
return index;
if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
&dma_spec))
return -ENODEV;

Yes this looks simple and it work.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config = 0;

unnecessary initialization.

Post by Srinivas Kandagatla
+ void __iomem *dml_base;
+ u32 consumer_id = 0, producer_id = 0;

unnecessary initialization.

Agree, I will fix it.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (IS_ERR_VALUE(producer_id) || IS_ERR_VALUE(consumer_id))

Is it actually possible for these ids to be very large values? Why not
just <= 0?

Ok.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+ return -ENODEV;
+
+ dml_base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel(1, (dml_base + DML_SW_RESET));
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel(config, (dml_base + DML_CONFIG));

unnecessary parens (throughout this file actually).

Yes.. Its mostly from 3.4 kernels. I will revisit these ones.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel(PRODUCER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_PRODUCER_PIPE_LOGICAL_SIZE));
+ writel(CONSUMER_PIPE_LOGICAL_SIZE,
+ (dml_base + DML_CONSUMER_PIPE_LOGICAL_SIZE));
+
+ /* Initialize Producer/consumer pipe id */
+ writel(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ (dml_base + DML_PIPE_ID));
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..d2c5aa45
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,17 @@

ditto for license text.

Will be done in v2.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

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[Srinivas Kandagatla]

On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.

Most of this code has been ported from qualcomm's 3.4 kernel.

This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Signed-off-by: Srinivas Kandagatla <***@linaro.org>
---
Changes since v1:
- Added licence text as spotted by Stephen B.
- Simplified dma channel lookup as suggested by Stephen B.
- Removed unnecessary parens spotted by Stephen B.
- in general some cleanup done.

Changes since RFC:
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W

drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 19 ++++-
drivers/mmc/host/mmci_qcom_dml.c | 171 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 31 +++++++
5 files changed, 232 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..3d9b84d 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI

If unsure, say N.

+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && QCOM_BAM_DMA
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..344c870 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#

obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..4f71888 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>

#include "mmci.h"
+#include "mmci_qcom_dml.h"

#define DRIVER_NAME "mmci-pl18x"

@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
* @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply
* @explicit_mclk_control: enable explicit mclk control in driver.
* @qcom_fifo: enables qcom specific fifo pio read logic.
+ * @qcom_dml: enables qcom specific dma glue for dma transfers.
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};

static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};

static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;

host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,11 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel) {
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
+ }
}

/*
@@ -569,6 +579,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ unsigned long flags = DMA_CTRL_ACK;

if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +604,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;

+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;

@@ -644,6 +658,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);

+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;

/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..dbacfb5
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,171 @@
+/*
+ *
+ * Copyright (c) 2014, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..412e9a3
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2014, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

[Linus Walleij]

On Fri, Jul 18, 2014 at 10:53 PM, Srinivas Kandagatla

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.
---
- Added licence text as spotted by Stephen B.
- Simplified dma channel lookup as suggested by Stephen B.
- Removed unnecessary parens spotted by Stephen B.
- in general some cleanup done.
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W

I really like this v2 version.
Reviewed-by: Linus Walleij <***@linaro.org>

Yours,
Linus Walleij
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[Stephen Boyd]

Post by Srinivas Kandagatla
@@ -468,6 +473,11 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel) {
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
+ }

Style nit: Braces aren't needed.

Post by Srinivas Kandagatla
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }

I think we need a memory barrier here. Does the DML need to be enabled
before the mmci driver sets MCI_DPSM_DMAENABLE? My understanding is that
relaxed accesses to different devices aren't ordered with respect to one
another. So not having a memory barrier here could cause the
consumer/producer to be enabled after MCI_DPSM_DMAENABLE is set in the
mmci hardware. Downstream I see that we have an mb(), but I think we
could just a wmb() because we're just ordering with the mmci hardware right?

Is there any ordering required between bam and dml? I think enabling bam
could happen after enabling the consumer unless we had a wmb() after we
kick off bam and before we write a 1 to DML_CONSUMER_START.

Post by Srinivas Kandagatla
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)

return type of u32?

Post by Srinivas Kandagatla
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}

Much cleaner!

Post by Srinivas Kandagatla
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+

We have an mb() here too. Not sure why though. There's lots of comments
downstream but not where it actually would help!

Post by Srinivas Kandagatla
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..412e9a3
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2014, Code Aurora Forum. All rights reserved.

Hmm I see:

Copyright (c) 2011, The Linux Foundation. All rights reserved.

in these files. Can you use that?

[Srinivas Kandagatla]

Post by Stephen Boyd

Post by Srinivas Kandagatla
@@ -468,6 +473,11 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel) {
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
+ }

Style nit: Braces aren't needed.

Will fix it in next spin.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }

I think we need a memory barrier here. Does the DML need to be enabled
before the mmci driver sets MCI_DPSM_DMAENABLE? My understanding is that
relaxed accesses to different devices aren't ordered with respect to one
another. So not having a memory barrier here could cause the
consumer/producer to be enabled after MCI_DPSM_DMAENABLE is set in the
mmci hardware. Downstream I see that we have an mb(), but I think we
could just a wmb() because we're just ordering with the mmci hardware right?

yes, I think wmb should work. I will fix this.

Post by Stephen Boyd
Is there any ordering required between bam and dml? I think enabling bam
could happen after enabling the consumer unless we had a wmb() after we
kick off bam and before we write a 1 to DML_CONSUMER_START.

Am not sure if there is any strict ordering requirement between bam and
dml. But I can see a wmb in bam_start_dma().

Post by Stephen Boyd

Post by Srinivas Kandagatla
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)

return type of u32?

This function is expected to return negative error codes. I think I
should change u32 to int in dml_hw_init().

Post by Stephen Boyd

Post by Srinivas Kandagatla
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}

Much cleaner!

Post by Srinivas Kandagatla
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+

We have an mb() here too. Not sure why though. There's lots of comments
downstream but not where it actually would help!

I will add mb here and try to add some comments here.

Post by Stephen Boyd

Post by Srinivas Kandagatla
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..412e9a3
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2014, Code Aurora Forum. All rights reserved.

Copyright (c) 2011, The Linux Foundation. All rights reserved.
in these files. Can you use that?

https://git.linaro.org/landing-teams/working/qualcomm/kernel.git/blob/refs/heads/inforce/ifc6410/v1.5:/drivers/mmc/host/msm_sdcc_dml.c
in 3.4 kernel has:

Copyright (c) 2011, Code Aurora Forum. All rights reserved.

Do you still want to add Linux Foundation copyright in it.

thanks,
srini
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[Srinivas Kandagatla]

On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.

Most of this code has been ported from qualcomm's 3.4 kernel.

This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Reviewed-by: Linus Walleij <***@linaro.org>
Signed-off-by: Srinivas Kandagatla <***@linaro.org>
---
Changes since v2:
- copied missing memory barriers from 3.4 driver, spotted by Stephen B.
- removed unecessary braceses spotted by Stephen B.
- copied exact copyright year from 3.4 kernel.

Changes since v1:
- Added licence text as spotted by Stephen B.
- Simplified dma channel lookup as suggested by Stephen B.
- Removed unnecessary parens spotted by Stephen B.
- in general some cleanup done.

Changes since RFC:
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W

drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 18 +++-
drivers/mmc/host/mmci_qcom_dml.c | 177 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 31 +++++++
5 files changed, 237 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..3d9b84d 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI

If unsure, say N.

+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && QCOM_BAM_DMA
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..344c870 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#

obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..9059570 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>

#include "mmci.h"
+#include "mmci_qcom_dml.h"

#define DRIVER_NAME "mmci-pl18x"

@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
* @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply
* @explicit_mclk_control: enable explicit mclk control in driver.
* @qcom_fifo: enables qcom specific fifo pio read logic.
+ * @qcom_dml: enables qcom specific dma glue for dma transfers.
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};

static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};

static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;

host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,10 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel)
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
}

/*
@@ -569,6 +578,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ unsigned long flags = DMA_CTRL_ACK;

if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +603,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;

+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;

@@ -644,6 +657,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);

+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;

/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..77404ee
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,177 @@
+/*
+ *
+ * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }
+
+ /* make sure the dml is configured before dma is triggered */
+ wmb();
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+
+ /* Make sure dml intialization is finished */
+ mb();
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..fc1d929
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

[Srinivas Kandagatla]

On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.

Most of this code has been ported from qualcomm's 3.4 kernel.

This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Reviewed-by: Linus Walleij <***@linaro.org>
Signed-off-by: Srinivas Kandagatla <***@linaro.org>
---
Changes since v3:
- moved copyright from Code Aurora to Linux Foundation, as
suggested by Stephen B.

Changes since v2:
- copied missing memory barriers from 3.4 driver, spotted by Stephen B.
- removed unecessary braceses spotted by Stephen B.
- copied exact copyright year from 3.4 kernel.

Changes since v1:
- Added licence text as spotted by Stephen B.
- Simplified dma channel lookup as suggested by Stephen B.
- Removed unnecessary parens spotted by Stephen B.
- in general some cleanup done.

Changes since RFC:
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W.

drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 18 +++-
drivers/mmc/host/mmci_qcom_dml.c | 177 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 31 +++++++
5 files changed, 237 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..3d9b84d 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI

If unsure, say N.

+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && QCOM_BAM_DMA
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..344c870 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#

obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..9059570 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>

#include "mmci.h"
+#include "mmci_qcom_dml.h"

#define DRIVER_NAME "mmci-pl18x"

@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
* @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply
* @explicit_mclk_control: enable explicit mclk control in driver.
* @qcom_fifo: enables qcom specific fifo pio read logic.
+ * @qcom_dml: enables qcom specific dma glue for dma transfers.
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};

static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};

static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;

host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,10 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel)
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
}

/*
@@ -569,6 +578,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ unsigned long flags = DMA_CTRL_ACK;

if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +603,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;

+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;

@@ -644,6 +657,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);

+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;

/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..300ef50
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,177 @@
+/*
+ *
+ * Copyright (c) 2011, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }
+
+ /* make sure the dml is configured before dma is triggered */
+ wmb();
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+
+ /* Make sure dml intialization is finished */
+ mb();
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..6e405d0
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2011, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

[Stephen Boyd]

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Reviewed-by: Stephen Boyd <***@codeaurora.org>

[Srinivas Kandagatla]

If its not too late, is it possible to queue this patch for v3.17?


---
srini

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.
---
- moved copyright from Code Aurora to Linux Foundation, as
suggested by Stephen B.
- copied missing memory barriers from 3.4 driver, spotted by Stephen B.
- removed unecessary braceses spotted by Stephen B.
- copied exact copyright year from 3.4 kernel.
- Added licence text as spotted by Stephen B.
- Simplified dma channel lookup as suggested by Stephen B.
- Removed unnecessary parens spotted by Stephen B.
- in general some cleanup done.
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W.
drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 18 +++-
drivers/mmc/host/mmci_qcom_dml.c | 177 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 31 +++++++
5 files changed, 237 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..3d9b84d 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI
If unsure, say N.
+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && QCOM_BAM_DMA
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..344c870 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#
obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..9059570 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>
#include "mmci.h"
+#include "mmci_qcom_dml.h"
#define DRIVER_NAME "mmci-pl18x"
@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};
static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};
static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;
host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,10 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel)
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
}
/*
@@ -569,6 +578,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ unsigned long flags = DMA_CTRL_ACK;
if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +603,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;
+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;
@@ -644,6 +657,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);
+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;
/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..300ef50
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,177 @@
+/*
+ *
+ * Copyright (c) 2011, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }
+
+ /* make sure the dml is configured before dma is triggered */
+ wmb();
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+
+ /* Make sure dml intialization is finished */
+ mb();
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..6e405d0
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2011, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */

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[Ulf Hansson]

On 29 July 2014 04:50, Srinivas Kandagatla

Post by Srinivas Kandagatla
On Qualcomm APQ8064 SOCs, SD card controller has an additional glue
called DML (Data Mover Local/Lite) to assist dma transfers.
This hardware needs to be setup before any dma transfer is requested.
DML itself is not a DMA engine, its just a gule between the SD card
controller and dma controller.
Most of this code has been ported from qualcomm's 3.4 kernel.
This patch adds the code necessary to intialize the hardware and setup
before doing any dma transfers.

Thanks! Queued for 3.18.

Kind regards
Uffe

Post by Srinivas Kandagatla
---
- moved copyright from Code Aurora to Linux Foundation, as
suggested by Stephen B.
- copied missing memory barriers from 3.4 driver, spotted by Stephen B.
- removed unecessary braceses spotted by Stephen B.
- copied exact copyright year from 3.4 kernel.
- Added licence text as spotted by Stephen B.
- Simplified dma channel lookup as suggested by Stephen B.
- Removed unnecessary parens spotted by Stephen B.
- in general some cleanup done.
- Moved qcom_dml.* to mmci_qcom_dml.* as suggested by Linus W.
- added BAM DMA dependency in Kconfig as suggested by Linus W.
drivers/mmc/host/Kconfig | 11 +++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/mmci.c | 18 +++-
drivers/mmc/host/mmci_qcom_dml.c | 177 +++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_qcom_dml.h | 31 +++++++
5 files changed, 237 insertions(+), 1 deletion(-)
create mode 100644 drivers/mmc/host/mmci_qcom_dml.c
create mode 100644 drivers/mmc/host/mmci_qcom_dml.h
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..3d9b84d 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -14,6 +14,17 @@ config MMC_ARMMMCI
If unsure, say N.
+config MMC_QCOM_DML
+ tristate "Qualcomm Data Mover for SD Card Controller"
+ depends on MMC_ARMMMCI && QCOM_BAM_DMA
+ default y
+ help
+ This selects the Qualcomm Data Mover lite/local on SD Card controller.
+ This option will enable the dma to work correctly, if you are using
+ Qcom SOCs and MMC, you would probably need this option to get DMA working.
+
+ if unsure, say N.
+
config MMC_PXA
tristate "Intel PXA25x/26x/27x Multimedia Card Interface support"
depends on ARCH_PXA
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 7f81ddf..344c870 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -3,6 +3,7 @@
#
obj-$(CONFIG_MMC_ARMMMCI) += mmci.o
+obj-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b66b351..9059570 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -43,6 +43,7 @@
#include <asm/sizes.h>
#include "mmci.h"
+#include "mmci_qcom_dml.h"
#define DRIVER_NAME "mmci-pl18x"
@@ -74,6 +75,7 @@ static unsigned int fmax = 515633;
*/
struct variant_data {
unsigned int clkreg;
@@ -97,6 +99,7 @@ struct variant_data {
bool pwrreg_nopower;
bool explicit_mclk_control;
bool qcom_fifo;
+ bool qcom_dml;
};
static struct variant_data variant_arm = {
@@ -205,6 +208,7 @@ static struct variant_data variant_qcom = {
.f_max = 208000000,
.explicit_mclk_control = true,
.qcom_fifo = true,
+ .qcom_dml = true,
};
static int mmci_card_busy(struct mmc_host *mmc)
@@ -418,6 +422,7 @@ static void mmci_dma_setup(struct mmci_host *host)
{
const char *rxname, *txname;
dma_cap_mask_t mask;
+ struct variant_data *variant = host->variant;
host->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
host->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
@@ -468,6 +473,10 @@ static void mmci_dma_setup(struct mmci_host *host)
if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
+
+ if (variant->qcom_dml && host->dma_rx_channel && host->dma_tx_channel)
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
}
/*
@@ -569,6 +578,7 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
struct dma_async_tx_descriptor *desc;
enum dma_data_direction buffer_dirn;
int nr_sg;
+ unsigned long flags = DMA_CTRL_ACK;
if (data->flags & MMC_DATA_READ) {
conf.direction = DMA_DEV_TO_MEM;
@@ -593,9 +603,12 @@ static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
if (nr_sg == 0)
return -EINVAL;
+ if (host->variant->qcom_dml)
+ flags |= DMA_PREP_INTERRUPT;
+
dmaengine_slave_config(chan, &conf);
desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
- conf.direction, DMA_CTRL_ACK);
+ conf.direction, flags);
if (!desc)
goto unmap_exit;
@@ -644,6 +657,9 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
dmaengine_submit(host->dma_desc_current);
dma_async_issue_pending(host->dma_current);
+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
datactrl |= MCI_DPSM_DMAENABLE;
/* Trigger the DMA transfer */
diff --git a/drivers/mmc/host/mmci_qcom_dml.c b/drivers/mmc/host/mmci_qcom_dml.c
new file mode 100644
index 0000000..300ef50
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.c
@@ -0,0 +1,177 @@
+/*
+ *
+ * Copyright (c) 2011, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/of.h>
+#include <linux/of_dma.h>
+#include <linux/bitops.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include "mmci.h"
+
+/* Registers */
+#define DML_CONFIG 0x00
+#define PRODUCER_CRCI_MSK GENMASK(1, 0)
+#define PRODUCER_CRCI_DISABLE 0
+#define PRODUCER_CRCI_X_SEL BIT(0)
+#define PRODUCER_CRCI_Y_SEL BIT(1)
+#define CONSUMER_CRCI_MSK GENMASK(3, 2)
+#define CONSUMER_CRCI_DISABLE 0
+#define CONSUMER_CRCI_X_SEL BIT(2)
+#define CONSUMER_CRCI_Y_SEL BIT(3)
+#define PRODUCER_TRANS_END_EN BIT(4)
+#define BYPASS BIT(16)
+#define DIRECT_MODE BIT(17)
+#define INFINITE_CONS_TRANS BIT(18)
+
+#define DML_SW_RESET 0x08
+#define DML_PRODUCER_START 0x0c
+#define DML_CONSUMER_START 0x10
+#define DML_PRODUCER_PIPE_LOGICAL_SIZE 0x14
+#define DML_CONSUMER_PIPE_LOGICAL_SIZE 0x18
+#define DML_PIPE_ID 0x1c
+#define PRODUCER_PIPE_ID_SHFT 0
+#define PRODUCER_PIPE_ID_MSK GENMASK(4, 0)
+#define CONSUMER_PIPE_ID_SHFT 16
+#define CONSUMER_PIPE_ID_MSK GENMASK(20, 16)
+
+#define DML_PRODUCER_BAM_BLOCK_SIZE 0x24
+#define DML_PRODUCER_BAM_TRANS_SIZE 0x28
+
+/* other definitions */
+#define PRODUCER_PIPE_LOGICAL_SIZE 4096
+#define CONSUMER_PIPE_LOGICAL_SIZE 4096
+
+#define DML_OFFSET 0x800
+
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+ u32 config;
+ void __iomem *base = host->base + DML_OFFSET;
+
+ if (data->flags & MMC_DATA_READ) {
+ /* Read operation: configure DML for producer operation */
+ /* Set producer CRCI-x and disable consumer CRCI */
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_X_SEL;
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /* Set the Producer BAM block size */
+ writel_relaxed(data->blksz, base + DML_PRODUCER_BAM_BLOCK_SIZE);
+
+ /* Set Producer BAM Transaction size */
+ writel_relaxed(data->blocks * data->blksz,
+ base + DML_PRODUCER_BAM_TRANS_SIZE);
+ /* Set Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config |= PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger producer */
+ writel_relaxed(1, base + DML_PRODUCER_START);
+ } else {
+ /* Write operation: configure DML for consumer operation */
+ /* Set consumer CRCI-x and disable producer CRCI*/
+ config = readl_relaxed(base + DML_CONFIG);
+ config = (config & ~CONSUMER_CRCI_MSK) | CONSUMER_CRCI_X_SEL;
+ config = (config & ~PRODUCER_CRCI_MSK) | PRODUCER_CRCI_DISABLE;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Clear Producer Transaction End bit */
+ config = readl_relaxed(base + DML_CONFIG);
+ config &= ~PRODUCER_TRANS_END_EN;
+ writel_relaxed(config, base + DML_CONFIG);
+ /* Trigger consumer */
+ writel_relaxed(1, base + DML_CONSUMER_START);
+ }
+
+ /* make sure the dml is configured before dma is triggered */
+ wmb();
+}
+
+static int of_get_dml_pipe_index(struct device_node *np, const char *name)
+{
+ int index;
+ struct of_phandle_args dma_spec;
+
+ index = of_property_match_string(np, "dma-names", name);
+
+ if (index < 0)
+ return -ENODEV;
+
+ if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
+ &dma_spec))
+ return -ENODEV;
+
+ if (dma_spec.args_count)
+ return dma_spec.args[0];
+
+ return -ENODEV;
+}
+
+/* Initialize the dml hardware connected to SD Card controller */
+int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ u32 config;
+ void __iomem *base;
+ u32 consumer_id, producer_id;
+
+ consumer_id = of_get_dml_pipe_index(np, "tx");
+ producer_id = of_get_dml_pipe_index(np, "rx");
+
+ if (producer_id < 0 || consumer_id < 0)
+ return -ENODEV;
+
+ base = host->base + DML_OFFSET;
+
+ /* Reset the DML block */
+ writel_relaxed(1, base + DML_SW_RESET);
+
+ /* Disable the producer and consumer CRCI */
+ config = (PRODUCER_CRCI_DISABLE | CONSUMER_CRCI_DISABLE);
+ /*
+ * Disable the bypass mode. Bypass mode will only be used
+ * if data transfer is to happen in PIO mode and don't
+ * want the BAM interface to connect with SDCC-DML.
+ */
+ config &= ~BYPASS;
+ /*
+ * Disable direct mode as we don't DML to MASTER the AHB bus.
+ * BAM connected with DML should MASTER the AHB bus.
+ */
+ config &= ~DIRECT_MODE;
+ /*
+ * Disable infinite mode transfer as we won't be doing any
+ * infinite size data transfers. All data transfer will be
+ * of finite data size.
+ */
+ config &= ~INFINITE_CONS_TRANS;
+ writel_relaxed(config, base + DML_CONFIG);
+
+ /*
+ * Initialize the logical BAM pipe size for producer
+ * and consumer.
+ */
+ writel_relaxed(PRODUCER_PIPE_LOGICAL_SIZE,
+ base + DML_PRODUCER_PIPE_LOGICAL_SIZE);
+ writel_relaxed(CONSUMER_PIPE_LOGICAL_SIZE,
+ base + DML_CONSUMER_PIPE_LOGICAL_SIZE);
+
+ /* Initialize Producer/consumer pipe id */
+ writel_relaxed(producer_id | (consumer_id << CONSUMER_PIPE_ID_SHFT),
+ base + DML_PIPE_ID);
+
+ /* Make sure dml intialization is finished */
+ mb();
+
+ return 0;
+}
diff --git a/drivers/mmc/host/mmci_qcom_dml.h b/drivers/mmc/host/mmci_qcom_dml.h
new file mode 100644
index 0000000..6e405d0
--- /dev/null
+++ b/drivers/mmc/host/mmci_qcom_dml.h
@@ -0,0 +1,31 @@
+/*
+ *
+ * Copyright (c) 2011, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef __MMC_QCOM_DML_H__
+#define __MMC_QCOM_DML_H__
+
+#ifdef CONFIG_MMC_QCOM_DML
+int dml_hw_init(struct mmci_host *host, struct device_node *np);
+void dml_start_xfer(struct mmci_host *host, struct mmc_data *data);
+#else
+static inline int dml_hw_init(struct mmci_host *host, struct device_node *np)
+{
+ return -ENOSYS;
+}
+static inline void dml_start_xfer(struct mmci_host *host, struct mmc_data *data)
+{
+}
+#endif /* CONFIG_MMC_QCOM_DML */
+
+#endif /* __MMC_QCOM_DML_H__ */
--
1.9.1

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