From: Derong Liu derong.liu@mediatek.com
commit 43e5fee317f4b0a48992b8b07935b1a3ac20ce84 upstream.
We found this issue on a 5G platform, during CMDQ error handling, if DMA status is active when it call msdc_reset_hw(), it means mmc host hw reset and DMA transfer will be parallel, mmc host may access sram region unexpectedly. According to the programming guide of mtk-sd host, it needs to wait for dma stop done after set dma stop.
This change should be applied to all SoCs.
Signed-off-by: Derong Liu derong.liu@mediatek.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210827071537.1034-1-derong.liu@mediatek.com Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/mmc/host/mtk-sd.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -8,6 +8,7 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/dma-mapping.h> +#include <linux/iopoll.h> #include <linux/ioport.h> #include <linux/irq.h> #include <linux/of_address.h> @@ -2330,6 +2331,7 @@ static void msdc_cqe_enable(struct mmc_h static void msdc_cqe_disable(struct mmc_host *mmc, bool recovery) { struct msdc_host *host = mmc_priv(mmc); + unsigned int val = 0;
/* disable cmdq irq */ sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INT_CMDQ); @@ -2339,6 +2341,9 @@ static void msdc_cqe_disable(struct mmc_ if (recovery) { sdr_set_field(host->base + MSDC_DMA_CTRL, MSDC_DMA_CTRL_STOP, 1); + if (WARN_ON(readl_poll_timeout(host->base + MSDC_DMA_CFG, val, + !(val & MSDC_DMA_CFG_STS), 1, 3000))) + return; msdc_reset_hw(host); } }