Re: [PATCH v3 3/7] mmc: sdhci-brcmstb: Fix SDHCI_RESET_ALL for CQHCI

Adrian Hunter
2022-10-25T13:10:14Z

On 24/10/22 20:54, Brian Norris wrote:
> [[ 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.
>
> Include this fix by way of the new sdhci_and_cqhci_reset() helper.
>
> Fixes: d46ba2d17f90 ("mmc: sdhci-brcmstb: Add support for Command Queuing (CQE)")
> Signed-off-by: Brian Norris <briannorris@chromium.org>

This patch is dependent on "mmc: cqhci: Provide
helper for resetting both SDHCI and CQHCI". Best point that out
in this commit message as well.

Otherwise:

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
>
> Changes in v3:
> - Use new SDHCI+CQHCI helper
>
> Changes in v2:
> - Rely on cqhci_deactivate() to handle NULL cqe_private, instead of
> moving around CQE capability flags
>
> drivers/mmc/host/sdhci-brcmstb.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-brcmstb.c b/drivers/mmc/host/sdhci-brcmstb.c
> index aff36a933ebe..55d8bd232695 100644
> --- a/drivers/mmc/host/sdhci-brcmstb.c
> +++ b/drivers/mmc/host/sdhci-brcmstb.c
> @@ -12,6 +12,7 @@
> #include <linux/bitops.h>
> #include <linux/delay.h>
>
> +#include "sdhci-cqhci.h"
> #include "sdhci-pltfm.h"
> #include "cqhci.h"
>
> @@ -55,7 +56,7 @@ 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);
>
> - sdhci_reset(host, mask);
> + sdhci_and_cqhci_reset(host, mask);
>
> /* Reset will clear this, so re-enable it */
> if (priv->flags & BRCMSTB_PRIV_FLAGS_GATE_CLOCK)