mmc/dw_mmc: Fix DMA descriptor corruption

In dwmci_prepare_data, the descriptors are allocated for DMA transfer.
These are allocated using the ALLOC_CACHE_ALIGN_BUFFER. This macro uses
the stack to allocate these descriptors. This becomes a problem if the
DMA transfer continues after the processor leaves the function in which
the descriptors were allocated.

Therefore, I have moved the allocated of the buffers up one level, to
dwmci_send_cmd(). The DMA transfer should be complete when leaving this
function.

Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Andy Fleming <afleming@gmail.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Pantelis Antoniou <panto@antoniou-consulting.com>
This commit is contained in:
Mischa Jonker 2013-07-26 14:08:14 +02:00 committed by Pantelis Antoniou
parent da61fa5f42
commit 2136d22630

View File

@ -41,12 +41,11 @@ static void dwmci_set_idma_desc(struct dwmci_idmac *idmac,
}
static void dwmci_prepare_data(struct dwmci_host *host,
struct mmc_data *data)
struct mmc_data *data, struct dwmci_idmac *cur_idmac)
{
unsigned long ctrl;
unsigned int i = 0, flags, cnt, blk_cnt;
ulong data_start, data_end, start_addr;
ALLOC_CACHE_ALIGN_BUFFER(struct dwmci_idmac, cur_idmac, data->blocks);
blk_cnt = data->blocks;
@ -111,6 +110,8 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
struct mmc_data *data)
{
struct dwmci_host *host = (struct dwmci_host *)mmc->priv;
ALLOC_CACHE_ALIGN_BUFFER(struct dwmci_idmac, cur_idmac,
data ? data->blocks : 0);
int flags = 0, i;
unsigned int timeout = 100000;
u32 retry = 10000;
@ -127,7 +128,7 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
dwmci_writel(host, DWMCI_RINTSTS, DWMCI_INTMSK_ALL);
if (data)
dwmci_prepare_data(host, data);
dwmci_prepare_data(host, data, cur_idmac);
dwmci_writel(host, DWMCI_CMDARG, cmd->cmdarg);