Re: [PATCH v3 5/7] mmc: sdhci-tegra: Fix SDHCI_RESET_ALL for CQHCI

From: Adrian Hunter
Date: Tue Oct 25 2022 - 09:11:02 EST


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: 3c4019f97978 ("mmc: tegra: HW Command Queue Support for Tegra SDMMC")
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>

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@xxxxxxxxx>

> ---
>
> Changes in v3:
> - Use new SDHCI+CQHCI helper
>
> Changes in v2:
> - Drop unnecessary 'enable_hwcq' check
>
> drivers/mmc/host/sdhci-tegra.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
> index 413925bce0ca..c71000a07656 100644
> --- a/drivers/mmc/host/sdhci-tegra.c
> +++ b/drivers/mmc/host/sdhci-tegra.c
> @@ -28,6 +28,7 @@
>
> #include <soc/tegra/common.h>
>
> +#include "sdhci-cqhci.h"
> #include "sdhci-pltfm.h"
> #include "cqhci.h"
>
> @@ -367,7 +368,7 @@ static void tegra_sdhci_reset(struct sdhci_host *host, u8 mask)
> const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
> u32 misc_ctrl, clk_ctrl, pad_ctrl;
>
> - sdhci_reset(host, mask);
> + sdhci_and_cqhci_reset(host, mask);
>
> if (!(mask & SDHCI_RESET_ALL))
> return;