From 2136d22630ef5acf36b90c45b6e44e964547b618 Mon Sep 17 00:00:00 2001 From: Mischa Jonker Date: Fri, 26 Jul 2013 14:08:14 +0200 Subject: [PATCH] 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 Cc: Alexey Brodkin Cc: Jaehoon Chung Cc: Andy Fleming Acked-by: Jaehoon Chung Acked-by: Pantelis Antoniou --- drivers/mmc/dw_mmc.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c index a82ee17..796a811 100644 --- a/drivers/mmc/dw_mmc.c +++ b/drivers/mmc/dw_mmc.c @@ -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); -- 2.7.4