From: Per Forlin <per.forlin@xxxxxxxxxxxxxx>
Buffers must be 4-byte aligned due to restrictions that the
PL18x FIFO accesses must be done in a 4-byte aligned manner.
Moreover DPSM_DMAREQCTL must be enabled for SDIO to support
writes for non 32-byte aligned sg element lengths. In PIO
mode any buffer length can be handled as long as the buffer
address is 4-byte aligned.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxxxxxx>
Signed-off-by: Per Forlin <per.forlin@xxxxxxxxxxxxxx>
Signed-off-by: Stefan Nilsson XK <stefan.xk.nilsson@xxxxxxxxxxxxxx>
---
drivers/mmc/host/mmci.c | 51 +++++++++++++++++++++++++++++++++++++++++-----
drivers/mmc/host/mmci.h | 7 ++++++
2 files changed, 52 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index b949e07..9ea2f13 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -45,6 +45,7 @@ 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
+ * @dma_sdio_req_ctrl: enable value for DMAREQCTL register for SDIO write
* @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)
@@ -60,6 +61,7 @@ static unsigned int fmax = 515633;
struct variant_data {
unsigned int clkreg;
unsigned int clkreg_enable;
+ unsigned int dma_sdio_req_ctrl;
unsigned int datalength_bits;
unsigned int fifosize;
unsigned int fifohalfsize;
@@ -102,6 +104,7 @@ static struct variant_data variant_ux500 = {
.fifohalfsize = 8 * 4,
.clkreg = MCI_CLK_ENABLE,
.clkreg_enable = MCI_ST_UX500_HWFCEN,
+ .dma_sdio_req_ctrl = MCI_ST_DPSM_DMAREQCTL,
.datalength_bits = 24,
.sdio = true,
.st_clkdiv = true,
@@ -114,6 +117,7 @@ static struct variant_data variant_ux500v2 = {
.fifohalfsize = 8 * 4,
.clkreg = MCI_CLK_ENABLE,
.clkreg_enable = MCI_ST_UX500_HWFCEN,
+ .dma_sdio_req_ctrl = MCI_ST_DPSM_DMAREQCTL,
.datalength_bits = 24,
.sdio = true,
.st_clkdiv = true,
@@ -123,6 +127,30 @@ static struct variant_data variant_ux500v2 = {
};
/*
+ * Validate mmc prerequisites
+ */
+static int mmci_validate_data(struct mmci_host *host,
+ struct mmc_data *data)
+{
+ if (!data)
+ return 0;
+
+ if (!is_power_of_2(data->blksz)) {
+ dev_err(mmc_dev(host->mmc),
+ "unsupported block size (%d bytes)\n", data->blksz);
+ return -EINVAL;
+ }
+
+ if (data->sg->offset & 3) {
+ dev_err(mmc_dev(host->mmc),
+ "unsupported alignment (0x%x)\n", data->sg->offset);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
* This must be called with host->lock held
*/
static void mmci_write_clkreg(struct mmci_host *host, u32 clk)
@@ -432,8 +460,12 @@ static int mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
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)
+ /*
+ * If less than or equal to the fifo size, don't bother with DMA.
+ * SDIO transfers may not be 4-byte aligned, fall back to PIO.
+ */
+ if (data->blksz * data->blocks <= variant->fifosize ||
+ (data->blksz * data->blocks) & 3)
return -EINVAL;
device = chan->device;
@@ -468,6 +500,7 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
{
int ret;
struct mmc_data *data = host->data;
+ struct variant_data *variant = host->variant;
ret = mmci_dma_prep_data(host, host->data, NULL);
if (ret)
@@ -482,6 +515,11 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
datactrl |= MCI_DPSM_DMAENABLE;
+ /* Some hardware versions need special flags for SDIO DMA write. */
+ if (variant->sdio && host->mmc->card && mmc_card_sdio(host->mmc->card)
+ && (data->flags & MMC_DATA_WRITE))
+ datactrl |= variant->dma_sdio_req_ctrl;
+
/* Trigger the DMA transfer */
writel(datactrl, host->base + MMCIDATACTRL);
@@ -526,6 +564,9 @@ static void mmci_pre_request(struct mmc_host *mmc, struct mmc_request *mrq,
if (!data)
return;
+ if (mmci_validate_data(host, mrq->data))
+ return;
+
if (data->host_cookie) {
data->host_cookie = 0;
return;
@@ -1019,10 +1060,8 @@ static void mmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
WARN_ON(host->mrq != NULL);
- if (mrq->data && !is_power_of_2(mrq->data->blksz)) {
- dev_err(mmc_dev(mmc), "unsupported block size (%d bytes)\n",
- mrq->data->blksz);
- mrq->cmd->error = -EINVAL;
+ mrq->cmd->error = mmci_validate_data(host, mrq->data);
+ if (mrq->cmd->error) {
mmc_request_done(mmc, mrq);
return;
}
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index d437ccf..095c01c 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -60,6 +60,13 @@
#define MCI_ST_DPSM_RWMOD (1 << 10)
#define MCI_ST_DPSM_SDIOEN (1 << 11)
/* Control register extensions in the ST Micro Ux500 versions */
+/*
+ * DMA request control is required for write
+ * if transfer size is not 32-byte aligned.
+ * DMA request control is also needed if the total
+ * transfer size is 32-byte aligned but any of the
+ * sg element lengths are not 32-byte aligned.
+ */
#define MCI_ST_DPSM_DMAREQCTL (1 << 12)
#define MCI_ST_DPSM_DBOOTMODEEN (1 << 13)
#define MCI_ST_DPSM_BUSYMODE (1 << 14)
--
1.7.5.4
--
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