The new CONFIG_DMA_API_DEBUG option correctly detects that
dma_sync_single_for_device is called without dma_map_single.
In the particular case of the STM32 SDMMC2 driver, this shouldn't lead
to errors as dma_sync_single_for_cpu is only called after successful
DMA, not before. In other cases though, dirty cache lines may be evicted
and written back to cache, just before dma_sync_single_for_cpu,
resulting in memory corruption.
Switch to using dma_map_single to fix this.
Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
---
drivers/mci/stm32_sdmmc2.c | 41 ++++++++++++++++++++------------------
1 file changed, 22 insertions(+), 19 deletions(-)
diff --git a/drivers/mci/stm32_sdmmc2.c b/drivers/mci/stm32_sdmmc2.c
index 1bfef1ccf0eb..84969a29d0f4 100644
--- a/drivers/mci/stm32_sdmmc2.c
+++ b/drivers/mci/stm32_sdmmc2.c
@@ -257,11 +257,12 @@ static void stm32_sdmmc2_pwron(struct stm32_sdmmc2_priv *priv)
udelay(DIV_ROUND_UP(74 * USEC_PER_SEC, priv->mci.clock));
}
-static void stm32_sdmmc2_start_data(struct stm32_sdmmc2_priv *priv,
+static int stm32_sdmmc2_start_data(struct stm32_sdmmc2_priv *priv,
struct mci_data *data, u32 data_length)
{
unsigned int num_bytes = data->blocks * data->blocksize;
- u32 data_ctrl, idmabase0;
+ dma_addr_t idmabase0;
+ u32 data_ctrl;
/* Configure the SDMMC DPSM (Data Path State Machine) */
data_ctrl = (__ilog2_u32(data->blocksize) <<
@@ -270,27 +271,27 @@ static void stm32_sdmmc2_start_data(struct stm32_sdmmc2_priv *priv,
if (data->flags & MMC_DATA_READ) {
data_ctrl |= SDMMC_DCTRL_DTDIR;
- idmabase0 = (u32)data->dest;
+ idmabase0 = dma_map_single(priv->dev, (void *)data->src, num_bytes,
+ DMA_FROM_DEVICE);
} else {
- idmabase0 = (u32)data->src;
+ idmabase0 = dma_map_single(priv->dev, (void *)data->src, num_bytes,
+ DMA_TO_DEVICE);
}
+ if (dma_mapping_error(priv->dev, idmabase0))
+ return DMA_ERROR_CODE;
+
/* Set the SDMMC DataLength value */
writel(data_length, priv->base + SDMMC_DLEN);
/* Write to SDMMC DCTRL */
writel(data_ctrl, priv->base + SDMMC_DCTRL);
- if (data->flags & MMC_DATA_WRITE)
- dma_sync_single_for_device(priv->dev, (unsigned long)idmabase0,
- num_bytes, DMA_TO_DEVICE);
- else
- dma_sync_single_for_device(priv->dev, (unsigned long)idmabase0,
- num_bytes, DMA_FROM_DEVICE);
-
/* Enable internal DMA */
writel(idmabase0, priv->base + SDMMC_IDMABASE0);
writel(SDMMC_IDMACTRL_IDMAEN, priv->base + SDMMC_IDMACTRL);
+
+ return idmabase0;
}
static void stm32_sdmmc2_start_cmd(struct stm32_sdmmc2_priv *priv,
@@ -415,7 +416,8 @@ static int stm32_sdmmc2_end_cmd(struct stm32_sdmmc2_priv *priv,
static int stm32_sdmmc2_end_data(struct stm32_sdmmc2_priv *priv,
struct mci_cmd *cmd,
- struct mci_data *data)
+ struct mci_data *data,
+ dma_addr_t dma_addr)
{
u32 mask = SDMMC_STA_DCRCFAIL | SDMMC_STA_DTIMEOUT |
SDMMC_STA_IDMATE | SDMMC_STA_DATAEND;
@@ -436,12 +438,10 @@ static int stm32_sdmmc2_end_data(struct stm32_sdmmc2_priv *priv,
return ret;
}
- if (data->flags & MMC_DATA_WRITE)
- dma_sync_single_for_cpu(priv->dev, (unsigned long)data->src,
- num_bytes, DMA_TO_DEVICE);
+ if (data->flags & MMC_DATA_READ)
+ dma_unmap_single(priv->dev, dma_addr, num_bytes, DMA_FROM_DEVICE);
else
- dma_sync_single_for_cpu(priv->dev, (unsigned long)data->dest,
- num_bytes, DMA_FROM_DEVICE);
+ dma_unmap_single(priv->dev, dma_addr, num_bytes, DMA_TO_DEVICE);
if (status & SDMMC_STA_DCRCFAIL) {
dev_err(priv->dev, "error SDMMC_STA_DCRCFAIL (0x%x) for cmd %d\n",
@@ -481,12 +481,15 @@ static int stm32_sdmmc2_send_cmd(struct mci_host *mci, struct mci_cmd *cmd,
{
struct stm32_sdmmc2_priv *priv = to_mci_host(mci);
u32 cmdat = data ? SDMMC_CMD_CMDTRANS : 0;
+ dma_addr_t dma_addr = DMA_ERROR_CODE;
u32 data_length = 0;
int ret;
if (data) {
data_length = data->blocks * data->blocksize;
- stm32_sdmmc2_start_data(priv, data, data_length);
+ dma_addr = stm32_sdmmc2_start_data(priv, data, data_length);
+ if (dma_addr == DMA_ERROR_CODE)
+ return -EFAULT;
}
stm32_sdmmc2_start_cmd(priv, cmd, cmdat, data_length);
@@ -497,7 +500,7 @@ static int stm32_sdmmc2_send_cmd(struct mci_host *mci, struct mci_cmd *cmd,
ret = stm32_sdmmc2_end_cmd(priv, cmd);
if (data && !ret)
- ret = stm32_sdmmc2_end_data(priv, cmd, data);
+ ret = stm32_sdmmc2_end_data(priv, cmd, data, dma_addr);
/* Clear flags */
writel(SDMMC_ICR_STATIC_FLAGS, priv->base + SDMMC_ICR);
--
2.39.2
