[3/5] mms: sdhci-esdhc-imx: Fix SDHCI_RESET_ALL for CQHCI

Message ID 20221017205610.3.I7d01f9ad11bacdc9213dee61b7918982aea39115@changeid
State New
Headers
Series mmc: sdhci controllers: Fix SDHCI_RESET_ALL for CQHCI |

Commit Message

Brian Norris Oct. 18, 2022, 3:57 a.m. UTC
  [[ 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@chromium.org>
---

 drivers/mmc/host/sdhci-esdhc-imx.c | 7 +++++++
 1 file changed, 7 insertions(+)
  

Comments

Bough Chen Oct. 18, 2022, 7:22 a.m. UTC | #1
> -----Original Message-----
> From: Brian Norris <briannorris@chromium.org>
> Sent: 2022年10月18日 11:57
> To: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: Shawn Lin <shawn.lin@rock-chips.com>; Adrian Hunter
> <adrian.hunter@intel.com>; Shawn Guo <shawnguo@kernel.org>; Fabio
> Estevam <festevam@gmail.com>; Faiz Abbas <faiz_abbas@ti.com>;
> dl-linux-imx <linux-imx@nxp.com>; Bough Chen <haibo.chen@nxp.com>; Al
> Cooper <alcooperx@gmail.com>; linux-mmc@vger.kernel.org; Pengutronix
> Kernel Team <kernel@pengutronix.de>; linux-kernel@vger.kernel.org; Florian
> Fainelli <f.fainelli@gmail.com>; Sascha Hauer <s.hauer@pengutronix.de>;
> Thierry Reding <thierry.reding@gmail.com>; Michal Simek
> <michal.simek@xilinx.com>; Jonathan Hunter <jonathanh@nvidia.com>;
> Sowjanya Komatineni <skomatineni@nvidia.com>;
> linux-arm-kernel@lists.infradead.org; Broadcom internal kernel review list
> <bcm-kernel-feedback-list@broadcom.com>; Brian Norris
> <briannorris@chromium.org>
> Subject: [PATCH 3/5] 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@chromium.org>
> ---
> 
>  drivers/mmc/host/sdhci-esdhc-imx.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c
> b/drivers/mmc/host/sdhci-esdhc-imx.c
> index 55981b0f0b10..222c83929e20 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -1288,6 +1288,13 @@ static void esdhc_set_uhs_signaling(struct
> sdhci_host *host, unsigned timing)
> 
>  static void esdhc_reset(struct sdhci_host *host, u8 mask)  {
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host);
> +
> +	if ((host->mmc->caps2 & MMC_CAP2_CQE) && (mask & SDHCI_RESET_ALL)
> &&
> +	    imx_data->socdata->flags & ESDHC_FLAG_CQHCI)

I think we can remove the condition " imx_data->socdata->flags & ESDHC_FLAG_CQHCI" here.
According to code logic, host->mmc->caps2 & MMC_CAP2_CQE means it already contain imx_data->socdata->flags & ESDHC_FLAG_CQHCI

Best Regards
Haibo Chen


> +		cqhci_deactivate(host->mmc);
> +
>  	sdhci_reset(host, mask);
> 
>  	sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
> --
> 2.38.0.413.g74048e4d9e-goog
  
Brian Norris Oct. 19, 2022, 9:56 p.m. UTC | #2
Hi,

On Tue, Oct 18, 2022 at 07:22:04AM +0000, Bough Chen wrote:
> > -----Original Message-----
> > From: Brian Norris <briannorris@chromium.org>
> > --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> > @@ -1288,6 +1288,13 @@ static void esdhc_set_uhs_signaling(struct
> > sdhci_host *host, unsigned timing)
> > 
> >  static void esdhc_reset(struct sdhci_host *host, u8 mask)  {
> > +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > +	struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host);
> > +
> > +	if ((host->mmc->caps2 & MMC_CAP2_CQE) && (mask & SDHCI_RESET_ALL)
> > &&
> > +	    imx_data->socdata->flags & ESDHC_FLAG_CQHCI)
> 
> I think we can remove the condition " imx_data->socdata->flags & ESDHC_FLAG_CQHCI" here.
> According to code logic, host->mmc->caps2 & MMC_CAP2_CQE means it already contain imx_data->socdata->flags & ESDHC_FLAG_CQHCI

I don't know why I had this in the first place. Maybe just to be
double-sure that caps flags aren't getting set elsewhere (e.g., by the
core)? But you're right, and I've dropped this in v2.

Thanks,
Brian
  

Patch

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 55981b0f0b10..222c83929e20 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -1288,6 +1288,13 @@  static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing)
 
 static void esdhc_reset(struct sdhci_host *host, u8 mask)
 {
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host);
+
+	if ((host->mmc->caps2 & MMC_CAP2_CQE) && (mask & SDHCI_RESET_ALL) &&
+	    imx_data->socdata->flags & ESDHC_FLAG_CQHCI)
+		cqhci_deactivate(host->mmc);
+
 	sdhci_reset(host, mask);
 
 	sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);