RE: [PATCH v2 4/7] mms: sdhci-esdhc-imx: Fix SDHCI_RESET_ALL for CQHCI

[Bough Chen]

> -----Original Message-----
> From: Brian Norris <briannorris@xxxxxxxxxxxx>
> Sent: 2022年10月20日 5:55
> To: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Cc: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>; Shawn Guo
> <shawnguo@xxxxxxxxxx>; Fabio Estevam <festevam@xxxxxxxxx>; Bough Chen
> <haibo.chen@xxxxxxx>; Broadcom internal kernel review list
> <bcm-kernel-feedback-list@xxxxxxxxxxxx>; dl-linux-imx <linux-imx@xxxxxxx>;
> Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>; Florian Fainelli
> <f.fainelli@xxxxxxxxx>; Michal Simek <michal.simek@xxxxxxxxxx>; Faiz Abbas
> <faiz_abbas@xxxxxx>; linux-mmc@xxxxxxxxxxxxxxx; Jonathan Hunter
> <jonathanh@xxxxxxxxxx>; Al Cooper <alcooperx@xxxxxxxxx>;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; Sowjanya Komatineni
> <skomatineni@xxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; Thierry Reding
> <thierry.reding@xxxxxxxxx>; Adrian Hunter <adrian.hunter@xxxxxxxxx>;
> Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>; Brian Norris
> <briannorris@xxxxxxxxxxxx>
> Subject: [PATCH v2 4/7] mms: sdhci-esdhc-imx: Fix SDHCI_RESET_ALL for CQHCI
> 
>  [[ 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.
> 
> Fixes: bb6e358169bf ("mmc: sdhci-esdhc-imx: add CMDQ support")
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>

Reviewed-by: Haibo Chen <haibo.chen@xxxxxxx>

> ---
> 
> Changes in v2:
>  - Drop unnecessary ESDHC_FLAG_CQHCI check
> 
>  drivers/mmc/host/sdhci-esdhc-imx.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c
> b/drivers/mmc/host/sdhci-esdhc-imx.c
> index 55981b0f0b10..c07df7b71b22 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -1288,6 +1288,9 @@ static void esdhc_set_uhs_signaling(struct sdhci_host
> *host, unsigned timing)
> 
>  static void esdhc_reset(struct sdhci_host *host, u8 mask)  {
> +	if ((host->mmc->caps2 & MMC_CAP2_CQE) && (mask &
> SDHCI_RESET_ALL))
> +		cqhci_deactivate(host->mmc);
> +
>  	sdhci_reset(host, mask);
> 
>  	sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
> --
> 2.38.0.413.g74048e4d9e-goog