| From b956dc9ec59ede6cc3041f3c825a2c06f8e062ac Mon Sep 17 00:00:00 2001 |
| From: Faiz Abbas <faiz_abbas@ti.com> |
| Date: Tue, 15 Oct 2019 00:08:49 +0530 |
| Subject: [PATCH] mmc: cqhci: Commit descriptors before setting the doorbell |
| |
| commit c07d0073b9ec80a139d07ebf78e9c30d2a28279e upstream. |
| |
| Add a write memory barrier to make sure that descriptors are actually |
| written to memory, before ringing the doorbell. |
| |
| Signed-off-by: Faiz Abbas <faiz_abbas@ti.com> |
| Acked-by: Adrian Hunter <adrian.hunter@intel.com> |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/drivers/mmc/host/cqhci.c b/drivers/mmc/host/cqhci.c |
| index f7bdae5354c3..5047f7343ffc 100644 |
| --- a/drivers/mmc/host/cqhci.c |
| +++ b/drivers/mmc/host/cqhci.c |
| @@ -611,7 +611,8 @@ static int cqhci_request(struct mmc_host *mmc, struct mmc_request *mrq) |
| cq_host->slot[tag].flags = 0; |
| |
| cq_host->qcnt += 1; |
| - |
| + /* Make sure descriptors are ready before ringing the doorbell */ |
| + wmb(); |
| cqhci_writel(cq_host, 1 << tag, CQHCI_TDBR); |
| if (!(cqhci_readl(cq_host, CQHCI_TDBR) & (1 << tag))) |
| pr_debug("%s: cqhci: doorbell not set for tag %d\n", |
| -- |
| 2.7.4 |
| |
