[PATCH 2/5] mmc: sdhci-brcmstb: Fix SDHCI_RESET_ALL for CQHCI

Brian Norris briannorris at chromium.org
Mon Oct 17 20:57:21 PDT 2022


 [[ NOTE: this is completely untested by the author, but included solely
    because, as noted in commit df57d73276b8 ("mmc: sdhci-pci: Fix
    SDHCI_RESET_ALL for CQHCI for Intel GLK-based controllers"), "other
    drivers using CQHCI might benefit from a similar change, if they
    also have CQHCI reset by SDHCI_RESET_ALL." We've now seen the same
    bug on at least MSM, Arasan, and Intel hardware. ]]

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 this may
occur in some suspend or error recovery scenarios.

Move around the CQE caps handling, because sdhci_setup_host() performs
resets before we've initialized CQHCI. This is the pattern followed in
other SDHCI/CQHCI drivers.

Fixes: d46ba2d17f90 ("mmc: sdhci-brcmstb: Add support for Command Queuing (CQE)")
Signed-off-by: Brian Norris <briannorris at chromium.org>
---

 drivers/mmc/host/sdhci-brcmstb.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-brcmstb.c b/drivers/mmc/host/sdhci-brcmstb.c
index aff36a933ebe..7f4bb362b923 100644
--- a/drivers/mmc/host/sdhci-brcmstb.c
+++ b/drivers/mmc/host/sdhci-brcmstb.c
@@ -55,6 +55,10 @@ static void brcmstb_reset(struct sdhci_host *host, u8 mask)
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);
 
+	if ((host->mmc->caps2 & MMC_CAP2_CQE) && (mask & SDHCI_RESET_ALL) &&
+	    (priv->flags & BRCMSTB_PRIV_FLAGS_HAS_CQE))
+		cqhci_deactivate(host->mmc);
+
 	sdhci_reset(host, mask);
 
 	/* Reset will clear this, so re-enable it */
@@ -209,7 +213,6 @@ static int sdhci_brcmstb_add_host(struct sdhci_host *host,
 		return sdhci_add_host(host);
 
 	dev_dbg(mmc_dev(host->mmc), "CQE is enabled\n");
-	host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
 	ret = sdhci_setup_host(host);
 	if (ret)
 		return ret;
@@ -230,6 +233,8 @@ static int sdhci_brcmstb_add_host(struct sdhci_host *host,
 		cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
 	}
 
+	host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
+
 	ret = cqhci_init(cq_host, host->mmc, dma64);
 	if (ret)
 		goto cleanup;
-- 
2.38.0.413.g74048e4d9e-goog




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