[PATCH v2 2/7] mmc: sdhci-of-arasan: Fix SDHCI_RESET_ALL for CQHCI

Brian Norris briannorris at chromium.org
Wed Oct 19 14:54:35 PDT 2022


SDHCI_RESET_ALL resets will reset the hardware CQE state, but we aren't
tracking that properly in software. When out of sync, we may trigger
various timeouts.

It's not typical to perform resets while CQE is enabled, but one
particular case I hit commonly enough: mmc_suspend() -> mmc_power_off().
Typically we will eventually deactivate CQE (cqhci_suspend() ->
cqhci_deactivate()), but that's not guaranteed -- in particular, if
we perform a partial (e.g., interrupted) system suspend.

The same bug was already found and fixed for two other drivers, in v5.7
and v5.9:

5cf583f1fb9c mmc: sdhci-msm: Deactivate CQE during SDHC reset
df57d73276b8 mmc: sdhci-pci: Fix SDHCI_RESET_ALL for CQHCI for Intel GLK-based controllers

The latter is especially prescient, saying "other drivers using CQHCI
might benefit from a similar change, if they also have CQHCI reset by
SDHCI_RESET_ALL."

So like these other patches, deactivate CQHCI when resetting the
controller.

Fixes: 84362d79f436 ("mmc: sdhci-of-arasan: Add CQHCI support for arasan,sdhci-5.1")
Cc: <stable at vger.kernel.org>
Signed-off-by: Brian Norris <briannorris at chromium.org>
---

Changes in v2:
 - Rely on cqhci_deactivate() to safely handle (ignore)
   not-yet-initialized CQE support

 drivers/mmc/host/sdhci-of-arasan.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 3997cad1f793..b30f0d6baf5b 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -366,6 +366,9 @@ static void sdhci_arasan_reset(struct sdhci_host *host, u8 mask)
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
 
+	if ((host->mmc->caps2 & MMC_CAP2_CQE) && (mask & SDHCI_RESET_ALL))
+		cqhci_deactivate(host->mmc);
+
 	sdhci_reset(host, mask);
 
 	if (sdhci_arasan->quirks & SDHCI_ARASAN_QUIRK_FORCE_CDTEST) {
-- 
2.38.0.413.g74048e4d9e-goog




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