[PATCH 01/19] mmc: mmci: regroup and define dma operations

From: Ludovic Barre
Date: Tue Jun 12 2018 - 09:19:26 EST

From: Ludovic Barre <ludovic.barre@xxxxxx>

Prepare mmci driver to manage dma interface by new property.
This patch defines and regroups dma operations for mmci drivers.
mmci_dma_XX prototypes are added to call member of mmci_dma_ops
if not null. Based on legacy need, a mmci dma interface has been
defined with:
-mmci_dma_setup
-mmci_dma_release
-mmci_dma_pre_req
-mmci_dma_start
-mmci_dma_finalize
-mmci_dma_post_req
-mmci_dma_error
-mmci_dma_get_next_data

A dma_priv is added to host structure to contain private dma needs.

Legacy dmaengine functions have been moved with just some adaptation on:
-dma_in_progress moves to dmaengine_priv structure, called in
dmaengine_error and dmaengine_finalize.
-centralized dma_unmap_sg into dmaengine_unmap, called by
dmaengine_error and dmaengine_finalize.

Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
---
drivers/mmc/host/Makefile | 2 +-
drivers/mmc/host/mmci.c | 437 ++----------------------------------------
drivers/mmc/host/mmci.h | 95 ++++++++--
drivers/mmc/host/mmci_dma.c | 450 ++++++++++++++++++++++++++++++++++++++++++++
drivers/mmc/host/mmci_dma.h | 31 +++
5 files changed, 579 insertions(+), 436 deletions(-)
create mode 100644 drivers/mmc/host/mmci_dma.c
create mode 100644 drivers/mmc/host/mmci_dma.h

diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 85dc132..daecaa98 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -4,7 +4,7 @@
#

obj-$(CONFIG_MMC_ARMMMCI) += armmmci.o
-armmmci-y := mmci.o
+armmmci-y := mmci.o mmci_dma.o
armmmci-$(CONFIG_MMC_QCOM_DML) += mmci_qcom_dml.o
obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index f184977..8868be0 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -42,84 +42,13 @@
#include <asm/io.h>

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

#define DRIVER_NAME "mmci-pl18x"

static unsigned int fmax = 515633;

-/**
- * struct variant_data - MMCI variant-specific quirks
- * @clkreg: default value for MCICLOCK register
- * @clkreg_enable: enable value for MMCICLOCK register
- * @clkreg_8bit_bus_enable: enable value for 8 bit bus
- * @clkreg_neg_edge_enable: enable value for inverted data/cmd output
- * @datalength_bits: number of bits in the MMCIDATALENGTH register
- * @fifosize: number of bytes that can be written when MMCI_TXFIFOEMPTY
- * is asserted (likewise for RX)
- * @fifohalfsize: number of bytes that can be written when MCI_TXFIFOHALFEMPTY
- * is asserted (likewise for RX)
- * @data_cmd_enable: enable value for data commands.
- * @st_sdio: enable ST specific SDIO logic
- * @st_clkdiv: true if using a ST-specific clock divider algorithm
- * @datactrl_mask_ddrmode: ddr mode mask in datactrl register.
- * @blksz_datactrl16: true if Block size is at b16..b30 position in datactrl register
- * @blksz_datactrl4: true if Block size is at b4..b16 position in datactrl
- * register
- * @datactrl_mask_sdio: SDIO enable mask in datactrl register
- * @pwrreg_powerup: power up value for MMCIPOWER register
- * @f_max: maximum clk frequency supported by the controller.
- * @signal_direction: input/out direction of bus signals can be indicated
- * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock
- * @busy_detect: true if the variant supports busy detection on DAT0.
- * @busy_dpsm_flag: bitmask enabling busy detection in the DPSM
- * @busy_detect_flag: bitmask identifying the bit in the MMCISTATUS register
- * indicating that the card is busy
- * @busy_detect_mask: bitmask identifying the bit in the MMCIMASK0 to mask for
- * getting busy end detection interrupts
- * @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.
- * @reversed_irq_handling: handle data irq before cmd irq.
- * @mmcimask1: true if variant have a MMCIMASK1 register.
- * @start_err: bitmask identifying the STARTBITERR bit inside MMCISTATUS
- * register.
- * @opendrain: bitmask identifying the OPENDRAIN bit inside MMCIPOWER register
- */
-struct variant_data {
- unsigned int clkreg;
- unsigned int clkreg_enable;
- unsigned int clkreg_8bit_bus_enable;
- unsigned int clkreg_neg_edge_enable;
- unsigned int datalength_bits;
- unsigned int fifosize;
- unsigned int fifohalfsize;
- unsigned int data_cmd_enable;
- unsigned int datactrl_mask_ddrmode;
- unsigned int datactrl_mask_sdio;
- bool st_sdio;
- bool st_clkdiv;
- bool blksz_datactrl16;
- bool blksz_datactrl4;
- u32 pwrreg_powerup;
- u32 f_max;
- bool signal_direction;
- bool pwrreg_clkgate;
- bool busy_detect;
- u32 busy_dpsm_flag;
- u32 busy_detect_flag;
- u32 busy_detect_mask;
- bool pwrreg_nopower;
- bool explicit_mclk_control;
- bool qcom_fifo;
- bool qcom_dml;
- bool reversed_irq_handling;
- bool mmcimask1;
- u32 start_err;
- u32 opendrain;
-};
-
static struct variant_data variant_arm = {
.fifosize = 16 * 4,
.fifohalfsize = 8 * 4,
@@ -130,6 +59,7 @@ static struct variant_data variant_arm = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_ROD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_arm_extended_fifo = {
@@ -141,6 +71,7 @@ static struct variant_data variant_arm_extended_fifo = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_ROD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_arm_extended_fifo_hwfc = {
@@ -153,6 +84,7 @@ static struct variant_data variant_arm_extended_fifo_hwfc = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_ROD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_u300 = {
@@ -171,6 +103,7 @@ static struct variant_data variant_u300 = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_OD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_nomadik = {
@@ -190,6 +123,7 @@ static struct variant_data variant_nomadik = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_OD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_ux500 = {
@@ -215,6 +149,7 @@ static struct variant_data variant_ux500 = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_OD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_ux500v2 = {
@@ -242,6 +177,7 @@ static struct variant_data variant_ux500v2 = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_OD,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_stm32 = {
@@ -259,6 +195,7 @@ static struct variant_data variant_stm32 = {
.f_max = 48000000,
.pwrreg_clkgate = true,
.pwrreg_nopower = true,
+ .mmci_dma = &dmaengine,
};

static struct variant_data variant_qcom = {
@@ -280,6 +217,7 @@ static struct variant_data variant_qcom = {
.mmcimask1 = true,
.start_err = MCI_STARTBITERR,
.opendrain = MCI_ROD,
+ .mmci_dma = &dmaengine,
};

/* Busy detection for the ST Micro variant */
@@ -355,7 +293,7 @@ static void mmci_write_pwrreg(struct mmci_host *host, u32 pwr)
/*
* This must be called with host->lock held
*/
-static void mmci_write_datactrlreg(struct mmci_host *host, u32 datactrl)
+void mmci_write_datactrlreg(struct mmci_host *host, u32 datactrl)
{
/* Keep busy mode in DPSM if enabled */
datactrl |= host->datactrl_reg & host->variant->busy_dpsm_flag;
@@ -480,281 +418,10 @@ static void mmci_init_sg(struct mmci_host *host, struct mmc_data *data)
sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
}

-/*
- * All the DMA operation mode stuff goes inside this ifdef.
- * This assumes that you have a generic DMA device interface,
- * no custom DMA interfaces are supported.
- */
-#ifdef CONFIG_DMA_ENGINE
-static void mmci_dma_setup(struct mmci_host *host)
-{
- const char *rxname, *txname;
- 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");
-
- /* initialize pre request cookie */
- host->next_data.cookie = 1;
-
- /*
- * If only an RX channel is specified, the driver will
- * attempt to use it bidirectionally, however if it is
- * is specified but cannot be located, DMA will be disabled.
- */
- if (host->dma_rx_channel && !host->dma_tx_channel)
- host->dma_tx_channel = host->dma_rx_channel;
-
- if (host->dma_rx_channel)
- rxname = dma_chan_name(host->dma_rx_channel);
- else
- rxname = "none";
-
- if (host->dma_tx_channel)
- txname = dma_chan_name(host->dma_tx_channel);
- else
- txname = "none";
-
- dev_info(mmc_dev(host->mmc), "DMA channels RX %s, TX %s\n",
- rxname, txname);
-
- /*
- * Limit the maximum segment size in any SG entry according to
- * the parameters of the DMA engine device.
- */
- if (host->dma_tx_channel) {
- struct device *dev = host->dma_tx_channel->device->dev;
- unsigned int max_seg_size = dma_get_max_seg_size(dev);
-
- if (max_seg_size < host->mmc->max_seg_size)
- host->mmc->max_seg_size = max_seg_size;
- }
- if (host->dma_rx_channel) {
- struct device *dev = host->dma_rx_channel->device->dev;
- unsigned int max_seg_size = dma_get_max_seg_size(dev);
-
- 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;
-}
-
-/*
- * This is used in or so inline it
- * so it can be discarded.
- */
-static inline void mmci_dma_release(struct mmci_host *host)
-{
- if (host->dma_rx_channel)
- dma_release_channel(host->dma_rx_channel);
- if (host->dma_tx_channel)
- dma_release_channel(host->dma_tx_channel);
- host->dma_rx_channel = host->dma_tx_channel = NULL;
-}
-
-static void mmci_dma_data_error(struct mmci_host *host)
-{
- dev_err(mmc_dev(host->mmc), "error during DMA transfer!\n");
- dmaengine_terminate_all(host->dma_current);
- host->dma_in_progress = false;
- host->dma_current = NULL;
- host->dma_desc_current = NULL;
- host->data->host_cookie = 0;
-}
-
-static void mmci_dma_unmap(struct mmci_host *host, struct mmc_data *data)
-{
- struct dma_chan *chan;
-
- if (data->flags & MMC_DATA_READ)
- chan = host->dma_rx_channel;
- else
- chan = host->dma_tx_channel;
-
- dma_unmap_sg(chan->device->dev, data->sg, data->sg_len,
- mmc_get_dma_dir(data));
-}
-
-static void mmci_dma_finalize(struct mmci_host *host, struct mmc_data *data)
-{
- u32 status;
- int i;
-
- /* Wait up to 1ms for the DMA to complete */
- for (i = 0; ; i++) {
- status = readl(host->base + MMCISTATUS);
- if (!(status & MCI_RXDATAAVLBLMASK) || i >= 100)
- break;
- udelay(10);
- }
-
- /*
- * Check to see whether we still have some data left in the FIFO -
- * this catches DMA controllers which are unable to monitor the
- * DMALBREQ and DMALSREQ signals while allowing us to DMA to non-
- * contiguous buffers. On TX, we'll get a FIFO underrun error.
- */
- if (status & MCI_RXDATAAVLBLMASK) {
- mmci_dma_data_error(host);
- if (!data->error)
- data->error = -EIO;
- }
-
- if (!data->host_cookie)
- mmci_dma_unmap(host, data);
-
- /*
- * Use of DMA with scatter-gather is impossible.
- * Give up with DMA and switch back to PIO mode.
- */
- if (status & MCI_RXDATAAVLBLMASK) {
- dev_err(mmc_dev(host->mmc), "buggy DMA detected. Taking evasive action.\n");
- mmci_dma_release(host);
- }
-
- host->dma_in_progress = false;
- host->dma_current = NULL;
- host->dma_desc_current = NULL;
-}
-
-/* prepares DMA channel and DMA descriptor, returns non-zero on failure */
-static int __mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
- struct dma_chan **dma_chan,
- struct dma_async_tx_descriptor **dma_desc)
-{
- struct variant_data *variant = host->variant;
- struct dma_slave_config conf = {
- .src_addr = host->phybase + MMCIFIFO,
- .dst_addr = host->phybase + MMCIFIFO,
- .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
- .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
- .src_maxburst = variant->fifohalfsize >> 2, /* # of words */
- .dst_maxburst = variant->fifohalfsize >> 2, /* # of words */
- .device_fc = false,
- };
- struct dma_chan *chan;
- struct dma_device *device;
- struct dma_async_tx_descriptor *desc;
- int nr_sg;
- unsigned long flags = DMA_CTRL_ACK;
-
- if (data->flags & MMC_DATA_READ) {
- conf.direction = DMA_DEV_TO_MEM;
- chan = host->dma_rx_channel;
- } else {
- conf.direction = DMA_MEM_TO_DEV;
- chan = host->dma_tx_channel;
- }
-
- /* If there's no DMA channel, fall back to PIO */
- if (!chan)
- return -EINVAL;
-
- /* If less than or equal to the fifo size, don't bother with DMA */
- if (data->blksz * data->blocks <= variant->fifosize)
- return -EINVAL;
-
- device = chan->device;
- nr_sg = dma_map_sg(device->dev, data->sg, data->sg_len,
- mmc_get_dma_dir(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, flags);
- if (!desc)
- goto unmap_exit;
-
- *dma_chan = chan;
- *dma_desc = desc;
-
- return 0;
-
- unmap_exit:
- dma_unmap_sg(device->dev, data->sg, data->sg_len,
- mmc_get_dma_dir(data));
- return -ENOMEM;
-}
-
-static inline int mmci_dma_prep_data(struct mmci_host *host,
- struct mmc_data *data)
-{
- /* Check if next job is already prepared. */
- if (host->dma_current && host->dma_desc_current)
- return 0;
-
- /* No job were prepared thus do it now. */
- return __mmci_dma_prep_data(host, data, &host->dma_current,
- &host->dma_desc_current);
-}
-
-static inline int mmci_dma_prep_next(struct mmci_host *host,
- struct mmc_data *data)
-{
- struct mmci_host_next *nd = &host->next_data;
- return __mmci_dma_prep_data(host, data, &nd->dma_chan, &nd->dma_desc);
-}
-
-static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
-{
- int ret;
- struct mmc_data *data = host->data;
-
- ret = mmci_dma_prep_data(host, host->data);
- if (ret)
- return ret;
-
- /* Okay, go for it. */
- dev_vdbg(mmc_dev(host->mmc),
- "Submit MMCI DMA job, sglen %d blksz %04x blks %04x flags %08x\n",
- data->sg_len, data->blksz, data->blocks, data->flags);
- host->dma_in_progress = true;
- 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 */
- mmci_write_datactrlreg(host, datactrl);
-
- /*
- * Let the MMCI say when the data is ended and it's time
- * to fire next DMA request. When that happens, MMCI will
- * call mmci_data_end()
- */
- writel(readl(host->base + MMCIMASK0) | MCI_DATAENDMASK,
- host->base + MMCIMASK0);
- return 0;
-}
-
-static void mmci_get_next_data(struct mmci_host *host, struct mmc_data *data)
-{
- struct mmci_host_next *next = &host->next_data;
-
- WARN_ON(data->host_cookie && data->host_cookie != next->cookie);
- WARN_ON(!data->host_cookie && (next->dma_desc || next->dma_chan));
-
- host->dma_desc_current = next->dma_desc;
- host->dma_current = next->dma_chan;
- next->dma_desc = NULL;
- next->dma_chan = NULL;
-}
-
static void mmci_pre_request(struct mmc_host *mmc, struct mmc_request *mrq)
{
struct mmci_host *host = mmc_priv(mmc);
struct mmc_data *data = mrq->data;
- struct mmci_host_next *nd = &host->next_data;

if (!data)
return;
@@ -764,8 +431,7 @@ static void mmci_pre_request(struct mmc_host *mmc, struct mmc_request *mrq)
if (mmci_validate_data(host, data))
return;

- if (!mmci_dma_prep_next(host, data))
- data->host_cookie = ++nd->cookie < 0 ? 1 : nd->cookie;
+ mmci_dma_pre_req(host, data);
}

static void mmci_post_request(struct mmc_host *mmc, struct mmc_request *mrq,
@@ -777,67 +443,9 @@ static void mmci_post_request(struct mmc_host *mmc, struct mmc_request *mrq,
if (!data || !data->host_cookie)
return;

- mmci_dma_unmap(host, data);
-
- if (err) {
- struct mmci_host_next *next = &host->next_data;
- struct dma_chan *chan;
- if (data->flags & MMC_DATA_READ)
- chan = host->dma_rx_channel;
- else
- chan = host->dma_tx_channel;
- dmaengine_terminate_all(chan);
-
- if (host->dma_desc_current == next->dma_desc)
- host->dma_desc_current = NULL;
-
- if (host->dma_current == next->dma_chan) {
- host->dma_in_progress = false;
- host->dma_current = NULL;
- }
-
- next->dma_desc = NULL;
- next->dma_chan = NULL;
- data->host_cookie = 0;
- }
-}
-
-#else
-/* Blank functions if the DMA engine is not available */
-static void mmci_get_next_data(struct mmci_host *host, struct mmc_data *data)
-{
-}
-static inline void mmci_dma_setup(struct mmci_host *host)
-{
-}
-
-static inline void mmci_dma_release(struct mmci_host *host)
-{
-}
-
-static inline void mmci_dma_unmap(struct mmci_host *host, struct mmc_data *data)
-{
-}
-
-static inline void mmci_dma_finalize(struct mmci_host *host,
- struct mmc_data *data)
-{
-}
-
-static inline void mmci_dma_data_error(struct mmci_host *host)
-{
-}
-
-static inline int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
-{
- return -ENOSYS;
+ mmci_dma_post_req(host, data, err);
}

-#define mmci_pre_request NULL
-#define mmci_post_request NULL
-
-#endif
-
static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
{
struct variant_data *variant = host->variant;
@@ -904,7 +512,7 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
* Attempt to use DMA operation mode, if this
* should fail, fall back to PIO mode
*/
- if (!mmci_dma_start_data(host, datactrl))
+ if (!mmci_dma_start(host, datactrl))
return;

/* IRQ mode, map the SG list for CPU reading/writing */
@@ -979,10 +587,7 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
u32 remain, success;

/* Terminate the DMA transfer */
- if (dma_inprogress(host)) {
- mmci_dma_data_error(host);
- mmci_dma_unmap(host, data);
- }
+ mmci_dma_error(host);

/*
* Calculate how far we are into the transfer. Note that
@@ -1020,8 +625,8 @@ mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
dev_err(mmc_dev(host->mmc), "stray MCI_DATABLOCKEND interrupt\n");

if (status & MCI_DATAEND || data->error) {
- if (dma_inprogress(host))
- mmci_dma_finalize(host, data);
+ mmci_dma_finalize(host, data);
+
mmci_stop_data(host);

if (!data->error)
@@ -1128,10 +733,8 @@ mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
if ((!sbc && !cmd->data) || cmd->error) {
if (host->data) {
/* Terminate the DMA transfer */
- if (dma_inprogress(host)) {
- mmci_dma_data_error(host);
- mmci_dma_unmap(host, host->data);
- }
+ mmci_dma_error(host);
+
mmci_stop_data(host);
}
mmci_request_end(host, host->mrq);
@@ -1399,7 +1002,7 @@ static void mmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
host->mrq = mrq;

if (mrq->data)
- mmci_get_next_data(host, mrq->data);
+ mmci_dma_get_next_data(host, mrq->data);

if (mrq->data && mrq->data->flags & MMC_DATA_READ)
mmci_start_data(host, mrq->data);
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index f91cdf7..a73bb98 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -195,13 +195,81 @@
#define MMCI_PINCTRL_STATE_OPENDRAIN "opendrain"

struct clk;
-struct variant_data;
struct dma_chan;

-struct mmci_host_next {
- struct dma_async_tx_descriptor *dma_desc;
- struct dma_chan *dma_chan;
- s32 cookie;
+/**
+ * struct variant_data - MMCI variant-specific quirks
+ * @clkreg: default value for MCICLOCK register
+ * @clkreg_enable: enable value for MMCICLOCK register
+ * @clkreg_8bit_bus_enable: enable value for 8 bit bus
+ * @clkreg_neg_edge_enable: enable value for inverted data/cmd output
+ * @datalength_bits: number of bits in the MMCIDATALENGTH register
+ * @fifosize: number of bytes that can be written when MMCI_TXFIFOEMPTY
+ * is asserted (likewise for RX)
+ * @fifohalfsize: number of bytes that can be written when MCI_TXFIFOHALFEMPTY
+ * is asserted (likewise for RX)
+ * @data_cmd_enable: enable value for data commands.
+ * @st_sdio: enable ST specific SDIO logic
+ * @st_clkdiv: true if using a ST-specific clock divider algorithm
+ * @datactrl_mask_ddrmode: ddr mode mask in datactrl register.
+ * @blksz_datactrl16: true if Block size is at b16..b30 position in datactrl
+ * register
+ * @blksz_datactrl4: true if Block size is at b4..b16 position in datactrl
+ * register
+ * @datactrl_mask_sdio: SDIO enable mask in datactrl register
+ * @pwrreg_powerup: power up value for MMCIPOWER register
+ * @f_max: maximum clk frequency supported by the controller.
+ * @signal_direction: input/out direction of bus signals can be indicated
+ * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock
+ * @busy_detect: true if the variant supports busy detection on DAT0.
+ * @busy_dpsm_flag: bitmask enabling busy detection in the DPSM
+ * @busy_detect_flag: bitmask identifying the bit in the MMCISTATUS register
+ * indicating that the card is busy
+ * @busy_detect_mask: bitmask identifying the bit in the MMCIMASK0 to mask for
+ * getting busy end detection interrupts
+ * @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.
+ * @reversed_irq_handling: handle data irq before cmd irq.
+ * @mmcimask1: true if variant have a MMCIMASK1 register.
+ * @start_err: bitmask identifying the STARTBITERR bit inside MMCISTATUS
+ * register.
+ * @opendrain: bitmask identifying the OPENDRAIN bit inside MMCIPOWER register
+ * @mmci_dma: Pointer to platform-specific DMA callbacks.
+ */
+struct variant_data {
+ unsigned int clkreg;
+ unsigned int clkreg_enable;
+ unsigned int clkreg_8bit_bus_enable;
+ unsigned int clkreg_neg_edge_enable;
+ unsigned int datalength_bits;
+ unsigned int fifosize;
+ unsigned int fifohalfsize;
+ unsigned int data_cmd_enable;
+ unsigned int datactrl_mask_ddrmode;
+ unsigned int datactrl_mask_sdio;
+ bool st_sdio;
+ bool st_clkdiv;
+ bool blksz_datactrl16;
+ bool blksz_datactrl4;
+ u32 pwrreg_powerup;
+ u32 f_max;
+ bool signal_direction;
+ bool pwrreg_clkgate;
+ bool busy_detect;
+ u32 busy_dpsm_flag;
+ u32 busy_detect_flag;
+ u32 busy_detect_mask;
+ bool pwrreg_nopower;
+ bool explicit_mclk_control;
+ bool qcom_fifo;
+ bool qcom_dml;
+ bool reversed_irq_handling;
+ bool mmcimask1;
+ u32 start_err;
+ u32 opendrain;
+ struct mmci_dma_ops *mmci_dma;
};

struct mmci_host {
@@ -244,18 +312,9 @@ struct mmci_host {
unsigned int size;
int (*get_rx_fifocnt)(struct mmci_host *h, u32 status, int remain);

-#ifdef CONFIG_DMA_ENGINE
- /* DMA stuff */
- struct dma_chan *dma_current;
- struct dma_chan *dma_rx_channel;
- struct dma_chan *dma_tx_channel;
- struct dma_async_tx_descriptor *dma_desc_current;
- struct mmci_host_next next_data;
- bool dma_in_progress;
-
-#define dma_inprogress(host) ((host)->dma_in_progress)
-#else
-#define dma_inprogress(host) (0)
-#endif
+ void *dma_priv;
};

+extern struct mmci_dma_ops dmaengine;
+
+void mmci_write_datactrlreg(struct mmci_host *host, u32 datactrl);
diff --git a/drivers/mmc/host/mmci_dma.c b/drivers/mmc/host/mmci_dma.c
new file mode 100644
index 0000000..98a542d
--- /dev/null
+++ b/drivers/mmc/host/mmci_dma.c
@@ -0,0 +1,450 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
+ * Author: Ludovic.barre@xxxxxx for STMicroelectronics.
+ */
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/card.h>
+#include <linux/scatterlist.h>
+
+#include "mmci.h"
+#include "mmci_dma.h"
+#include "mmci_qcom_dml.h"
+
+int mmci_dma_setup(struct mmci_host *host)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->setup)
+ return mmci_dma->setup(host);
+
+ return 0;
+}
+
+void mmci_dma_release(struct mmci_host *host)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->release)
+ mmci_dma->release(host);
+}
+
+void mmci_dma_pre_req(struct mmci_host *host, struct mmc_data *data)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->pre_req)
+ mmci_dma->pre_req(host, data);
+}
+
+int mmci_dma_start(struct mmci_host *host, unsigned int datactrl)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->start)
+ return mmci_dma->start(host, datactrl);
+
+ return -EINVAL;
+}
+
+void mmci_dma_finalize(struct mmci_host *host, struct mmc_data *data)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->finalize)
+ mmci_dma->finalize(host, data);
+}
+
+void mmci_dma_post_req(struct mmci_host *host,
+ struct mmc_data *data, int err)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->post_req)
+ mmci_dma->post_req(host, data, err);
+}
+
+void mmci_dma_error(struct mmci_host *host)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->error)
+ mmci_dma->error(host);
+}
+
+void mmci_dma_get_next_data(struct mmci_host *host, struct mmc_data *data)
+{
+ struct mmci_dma_ops *mmci_dma = host->variant->mmci_dma;
+
+ if (mmci_dma && mmci_dma->get_next_data)
+ mmci_dma->get_next_data(host, data);
+}
+
+#ifdef CONFIG_DMA_ENGINE
+struct dmaengine_next {
+ struct dma_async_tx_descriptor *dma_desc;
+ struct dma_chan *dma_chan;
+ s32 cookie;
+};
+
+struct dmaengine_priv {
+ struct dma_chan *dma_current;
+ struct dma_chan *dma_rx_channel;
+ struct dma_chan *dma_tx_channel;
+ struct dma_async_tx_descriptor *dma_desc_current;
+ struct dmaengine_next next_data;
+ bool dma_in_progress;
+};
+
+#define dma_inprogress(dmae) ((dmae)->dma_in_progress)
+
+static int dmaengine_setup(struct mmci_host *host)
+{
+ const char *rxname, *txname;
+ struct variant_data *variant = host->variant;
+ struct dmaengine_priv *dmae;
+
+ dmae = devm_kzalloc(mmc_dev(host->mmc), sizeof(*dmae), GFP_KERNEL);
+ if (!dmae)
+ return -ENOMEM;
+
+ host->dma_priv = dmae;
+
+ dmae->dma_rx_channel = dma_request_slave_channel(mmc_dev(host->mmc),
+ "rx");
+ dmae->dma_tx_channel = dma_request_slave_channel(mmc_dev(host->mmc),
+ "tx");
+
+ /* initialize pre request cookie */
+ dmae->next_data.cookie = 1;
+
+ /*
+ * If only an RX channel is specified, the driver will
+ * attempt to use it bidirectionally, however if it is
+ * is specified but cannot be located, DMA will be disabled.
+ */
+ if (dmae->dma_rx_channel && !dmae->dma_tx_channel)
+ dmae->dma_tx_channel = dmae->dma_rx_channel;
+
+ if (dmae->dma_rx_channel)
+ rxname = dma_chan_name(dmae->dma_rx_channel);
+ else
+ rxname = "none";
+
+ if (dmae->dma_tx_channel)
+ txname = dma_chan_name(dmae->dma_tx_channel);
+ else
+ txname = "none";
+
+ dev_info(mmc_dev(host->mmc), "DMA channels RX %s, TX %s\n",
+ rxname, txname);
+
+ /*
+ * Limit the maximum segment size in any SG entry according to
+ * the parameters of the DMA engine device.
+ */
+ if (dmae->dma_tx_channel) {
+ struct device *dev = dmae->dma_tx_channel->device->dev;
+ unsigned int max_seg_size = dma_get_max_seg_size(dev);
+
+ if (max_seg_size < host->mmc->max_seg_size)
+ host->mmc->max_seg_size = max_seg_size;
+ }
+ if (dmae->dma_rx_channel) {
+ struct device *dev = dmae->dma_rx_channel->device->dev;
+ unsigned int max_seg_size = dma_get_max_seg_size(dev);
+
+ if (max_seg_size < host->mmc->max_seg_size)
+ host->mmc->max_seg_size = max_seg_size;
+ }
+
+ if (variant->qcom_dml && dmae->dma_rx_channel && dmae->dma_tx_channel)
+ if (dml_hw_init(host, host->mmc->parent->of_node))
+ variant->qcom_dml = false;
+
+ return 0;
+}
+
+static inline void dmaengine_release(struct mmci_host *host)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+
+ if (dmae->dma_rx_channel)
+ dma_release_channel(dmae->dma_rx_channel);
+ if (dmae->dma_tx_channel)
+ dma_release_channel(dmae->dma_tx_channel);
+
+ dmae->dma_rx_channel = dmae->dma_tx_channel = NULL;
+}
+
+static void dmaengine_unmap(struct mmci_host *host, struct mmc_data *data)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ struct dma_chan *chan;
+
+ if (data->flags & MMC_DATA_READ)
+ chan = dmae->dma_rx_channel;
+ else
+ chan = dmae->dma_tx_channel;
+
+ dma_unmap_sg(chan->device->dev, data->sg, data->sg_len,
+ mmc_get_dma_dir(data));
+}
+
+static void dmaengine_error(struct mmci_host *host)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+
+ if (!dma_inprogress(dmae))
+ return;
+
+ dev_err(mmc_dev(host->mmc), "error during DMA transfer!\n");
+ dmaengine_terminate_all(dmae->dma_current);
+ dmae->dma_in_progress = false;
+ dmae->dma_current = NULL;
+ dmae->dma_desc_current = NULL;
+ host->data->host_cookie = 0;
+
+ dmaengine_unmap(host, host->data);
+}
+
+static void dmaengine_finalize(struct mmci_host *host, struct mmc_data *data)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ u32 status;
+ int i;
+
+ if (!dma_inprogress(dmae))
+ return;
+
+ /* Wait up to 1ms for the DMA to complete */
+ for (i = 0; ; i++) {
+ status = readl(host->base + MMCISTATUS);
+ if (!(status & MCI_RXDATAAVLBLMASK) || i >= 100)
+ break;
+ udelay(10);
+ }
+
+ /*
+ * Check to see whether we still have some data left in the FIFO -
+ * this catches DMA controllers which are unable to monitor the
+ * DMALBREQ and DMALSREQ signals while allowing us to DMA to non-
+ * contiguous buffers. On TX, we'll get a FIFO underrun error.
+ */
+ if (status & MCI_RXDATAAVLBLMASK) {
+ dmaengine_error(host);
+ if (!data->error)
+ data->error = -EIO;
+ }
+
+ if (!data->host_cookie)
+ dmaengine_unmap(host, data);
+
+ /*
+ * Use of DMA with scatter-gather is impossible.
+ * Give up with DMA and switch back to PIO mode.
+ */
+ if (status & MCI_RXDATAAVLBLMASK) {
+ dev_err(mmc_dev(host->mmc),
+ "buggy DMA detected. Taking evasive action.\n");
+ dmaengine_release(host);
+ }
+
+ dmae->dma_in_progress = false;
+ dmae->dma_current = NULL;
+ dmae->dma_desc_current = NULL;
+}
+
+/* prepares DMA channel and DMA descriptor, returns non-zero on failure */
+static int __dmaengine_prep_data(struct mmci_host *host, struct mmc_data *data,
+ struct dma_chan **dma_chan,
+ struct dma_async_tx_descriptor **dma_desc)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ struct variant_data *variant = host->variant;
+ struct dma_slave_config conf = {
+ .src_addr = host->phybase + MMCIFIFO,
+ .dst_addr = host->phybase + MMCIFIFO,
+ .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
+ .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
+ .src_maxburst = variant->fifohalfsize >> 2, /* # of words */
+ .dst_maxburst = variant->fifohalfsize >> 2, /* # of words */
+ .device_fc = false,
+ };
+ struct dma_chan *chan;
+ struct dma_device *device;
+ struct dma_async_tx_descriptor *desc;
+ int nr_sg;
+ unsigned long flags = DMA_CTRL_ACK;
+
+ if (data->flags & MMC_DATA_READ) {
+ conf.direction = DMA_DEV_TO_MEM;
+ chan = dmae->dma_rx_channel;
+ } else {
+ conf.direction = DMA_MEM_TO_DEV;
+ chan = dmae->dma_tx_channel;
+ }
+
+ /* If there's no DMA channel, fall back to PIO */
+ if (!chan)
+ return -EINVAL;
+
+ /* If less than or equal to the fifo size, don't bother with DMA */
+ if (data->blksz * data->blocks <= variant->fifosize)
+ return -EINVAL;
+
+ device = chan->device;
+ nr_sg = dma_map_sg(device->dev, data->sg, data->sg_len,
+ mmc_get_dma_dir(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, flags);
+ if (!desc)
+ goto unmap_exit;
+
+ *dma_chan = chan;
+ *dma_desc = desc;
+
+ return 0;
+
+ unmap_exit:
+ dmaengine_unmap(host, data);
+ return -ENOMEM;
+}
+
+static inline int dmaengine_prep_data(struct mmci_host *host,
+ struct mmc_data *data)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+
+ /* Check if next job is already prepared. */
+ if (dmae->dma_current && dmae->dma_desc_current)
+ return 0;
+
+ /* No job were prepared thus do it now. */
+ return __dmaengine_prep_data(host, data, &dmae->dma_current,
+ &dmae->dma_desc_current);
+}
+
+static inline int dmaengine_prep_next(struct mmci_host *host,
+ struct mmc_data *data)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ struct dmaengine_next *nd = &dmae->next_data;
+
+ return __dmaengine_prep_data(host, data, &nd->dma_chan, &nd->dma_desc);
+}
+
+static int dmaengine_start(struct mmci_host *host, unsigned int datactrl)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ struct mmc_data *data = host->data;
+ int ret;
+
+ ret = dmaengine_prep_data(host, host->data);
+ if (ret)
+ return ret;
+
+ /* Okay, go for it. */
+ dev_vdbg(mmc_dev(host->mmc),
+ "Submit MMCI DMA job, sglen %d blksz %04x blks %04x flags %08x\n",
+ data->sg_len, data->blksz, data->blocks, data->flags);
+ dmae->dma_in_progress = true;
+ dmaengine_submit(dmae->dma_desc_current);
+ dma_async_issue_pending(dmae->dma_current);
+
+ if (host->variant->qcom_dml)
+ dml_start_xfer(host, data);
+
+ datactrl |= MCI_DPSM_DMAENABLE;
+
+ /* Trigger the DMA transfer */
+ mmci_write_datactrlreg(host, datactrl);
+
+ /*
+ * Let the MMCI say when the data is ended and it's time
+ * to fire next DMA request. When that happens, MMCI will
+ * call mmci_data_end()
+ */
+ writel(readl(host->base + MMCIMASK0) | MCI_DATAENDMASK,
+ host->base + MMCIMASK0);
+ return 0;
+}
+
+static void dmaengine_get_next_data(struct mmci_host *host,
+ struct mmc_data *data)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ struct dmaengine_next *next = &dmae->next_data;
+
+ WARN_ON(data->host_cookie && data->host_cookie != next->cookie);
+ WARN_ON(!data->host_cookie && (next->dma_desc || next->dma_chan));
+
+ dmae->dma_desc_current = next->dma_desc;
+ dmae->dma_current = next->dma_chan;
+ next->dma_desc = NULL;
+ next->dma_chan = NULL;
+}
+
+static void dmaengine_pre_req(struct mmci_host *host, struct mmc_data *data)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+ struct dmaengine_next *nd = &dmae->next_data;
+
+ if (!dmaengine_prep_next(host, data))
+ data->host_cookie = ++nd->cookie < 0 ? 1 : nd->cookie;
+}
+
+static void dmaengine_post_req(struct mmci_host *host,
+ struct mmc_data *data, int err)
+{
+ struct dmaengine_priv *dmae = host->dma_priv;
+
+ dmaengine_unmap(host, data);
+
+ if (err) {
+ struct dmaengine_next *next = &dmae->next_data;
+ struct dma_chan *chan;
+
+ if (data->flags & MMC_DATA_READ)
+ chan = dmae->dma_rx_channel;
+ else
+ chan = dmae->dma_tx_channel;
+ dmaengine_terminate_all(chan);
+
+ if (dmae->dma_desc_current == next->dma_desc)
+ dmae->dma_desc_current = NULL;
+
+ if (dmae->dma_current == next->dma_chan) {
+ dmae->dma_in_progress = false;
+ dmae->dma_current = NULL;
+ }
+
+ next->dma_desc = NULL;
+ next->dma_chan = NULL;
+ data->host_cookie = 0;
+ }
+}
+
+struct mmci_dma_ops dmaengine = {
+ .setup = dmaengine_setup,
+ .release = dmaengine_release,
+ .pre_req = dmaengine_pre_req,
+ .start = dmaengine_start,
+ .finalize = dmaengine_finalize,
+ .post_req = dmaengine_post_req,
+ .error = dmaengine_error,
+ .get_next_data = dmaengine_get_next_data,
+};
+#else
+struct mmci_dma_ops dmaengine = {};
+#endif
diff --git a/drivers/mmc/host/mmci_dma.h b/drivers/mmc/host/mmci_dma.h
new file mode 100644
index 0000000..33e4e8a
--- /dev/null
+++ b/drivers/mmc/host/mmci_dma.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
+ * Author: Ludovic.barre@xxxxxx for STMicroelectronics.
+ */
+#ifndef __MMC_DMA_H__
+#define __MMC_DMA_H__
+
+struct mmci_dma_ops {
+ int (*setup)(struct mmci_host *host);
+ void (*release)(struct mmci_host *host);
+ void (*pre_req)(struct mmci_host *host, struct mmc_data *data);
+ int (*start)(struct mmci_host *host, unsigned int datactrl);
+ void (*finalize)(struct mmci_host *host, struct mmc_data *data);
+ void (*post_req)(struct mmci_host *host,
+ struct mmc_data *data, int err);
+ void (*error)(struct mmci_host *host);
+ void (*get_next_data)(struct mmci_host *host, struct mmc_data *data);
+};
+
+int mmci_dma_setup(struct mmci_host *host);
+int mmci_dma_start(struct mmci_host *host, unsigned int datactrl);
+void mmci_dma_release(struct mmci_host *host);
+void mmci_dma_pre_req(struct mmci_host *host, struct mmc_data *data);
+void mmci_dma_finalize(struct mmci_host *host, struct mmc_data *data);
+void mmci_dma_post_req(struct mmci_host *host,
+ struct mmc_data *data, int err);
+void mmci_dma_error(struct mmci_host *host);
+void mmci_dma_get_next_data(struct mmci_host *host, struct mmc_data *data);
+
+#endif /* __MMC_DMA_H__ */
--
2.7.4