Re: [PATCH v5 3/3] mmc: sdhci-tegra: Issue CMD and DAT resets together

Adrian Hunter
2022-09-27T12:49:18Z

On 27/09/22 14:13, Prathamesh Shete wrote:
> In case of error condition to avoid system crash
> Tegra SDMMC controller requires CMD and DAT resets
> issued together. SDHCI controller FSM goes into
> bad state due to rapid SD card hot-plug event.
> Issuing reset on the CMD FSM before DATA FSM results
> in kernel panic, hence add support to issue CMD and
> DAT resets together.
> This is applicable to Tegra186 and later chips.
>
> Signed-off-by: Aniruddha TVS Rao <anrao@nvidia.com>
> Signed-off-by: Prathamesh Shete <pshete@nvidia.com>

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

> ---
> drivers/mmc/host/sdhci-tegra.c | 3 ++-
> drivers/mmc/host/sdhci.c | 5 +++++
> drivers/mmc/host/sdhci.h | 2 ++
> 3 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
> index 46f37cc26dbb..61dc5ee0726d 100644
> --- a/drivers/mmc/host/sdhci-tegra.c
> +++ b/drivers/mmc/host/sdhci-tegra.c
> @@ -1536,7 +1536,8 @@ static const struct sdhci_pltfm_data sdhci_tegra186_pdata = {
> SDHCI_QUIRK_NO_HISPD_BIT |
> SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
> SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
> - .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
> + .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
> + SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER,
> .ops = &tegra186_sdhci_ops,
> };
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 2b5dda521b0e..8512a69f1aae 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -270,6 +270,11 @@ enum sdhci_reset_reason {
>
> static void sdhci_reset_for_reason(struct sdhci_host *host, enum sdhci_reset_reason reason)
> {
> + if (host->quirks2 &
> + SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER) {
> + sdhci_do_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
> + return;
> + }
> switch (reason) {
> case SDHCI_RESET_FOR_INIT:
> sdhci_do_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index d750c464bd1e..6a5766774b05 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -478,6 +478,8 @@ struct sdhci_host {
> * block count.
> */
> #define SDHCI_QUIRK2_USE_32BIT_BLK_CNT (1<<18)
> +/* Issue CMD and DATA reset together */
> +#define SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER (1<<19)
>
> int irq; /* Device IRQ */
> void __iomem *ioaddr; /* Mapped address */