diff mbox series

[v4,3/4] mmc: sdhci-tegra: Issue CMD and DAT resets together

Message ID 20220927100946.19482-3-pshete@nvidia.com
State Changes Requested
Headers show
Series [v4,1/4] mmc: sdhci-tegra: Separate Tegra194 and Tegra234 SoC data | expand

Commit Message

Prathamesh Shete Sept. 27, 2022, 10:09 a.m. UTC 
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>
---
 drivers/mmc/host/sdhci-tegra.c | 3 ++-
 drivers/mmc/host/sdhci.c       | 8 +++++++-
 drivers/mmc/host/sdhci.h       | 2 ++
 3 files changed, 11 insertions(+), 2 deletions(-)

Comments

Adrian Hunter Sept. 27, 2022, 10:23 a.m. UTC | #1 
On 27/09/22 13:09, 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>
> ---
>  drivers/mmc/host/sdhci-tegra.c | 3 ++-
>  drivers/mmc/host/sdhci.c       | 8 +++++++-
>  drivers/mmc/host/sdhci.h       | 2 ++
>  3 files changed, 11 insertions(+), 2 deletions(-)
> 
> 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..5123ec3fc74a 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -266,12 +266,14 @@ enum sdhci_reset_reason {
>  	SDHCI_RESET_FOR_TUNING_ABORT,
>  	SDHCI_RESET_FOR_CARD_REMOVED,
>  	SDHCI_RESET_FOR_CQE_RECOVERY,
> +	SDHCI_RESET_FOR_CMD_DAT_TOGETHER,
>  };
>  
>  static void sdhci_reset_for_reason(struct sdhci_host *host, enum sdhci_reset_reason reason)
>  {
>  	switch (reason) {
>  	case SDHCI_RESET_FOR_INIT:
> +	case SDHCI_RESET_FOR_CMD_DAT_TOGETHER:
>  		sdhci_do_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
>  		break;
>  	case SDHCI_RESET_FOR_REQUEST_ERROR:
> @@ -3084,7 +3086,11 @@ static bool sdhci_request_done(struct sdhci_host *host)
>  			/* This is to force an update */
>  			host->ops->set_clock(host, host->clock);
>  
> -		sdhci_reset_for(host, REQUEST_ERROR);
> +		if (host->quirks2 &
> +			SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER)
> +			sdhci_reset_for(host, CMD_DAT_TOGETHER);
> +		else
> +			sdhci_reset_for(host, REQUEST_ERROR);

This is what I am trying to avoid because it is inconsistent.
Consider:
 - why is the quirk needed for some REQUEST_ERRORs but not others?
 - or why is the quirk not needed for all CMD / DAT resets?

So, I was expecting the quirk to be applied in sdhci_reset_for_reason()
not here.

>  
>  		host->pending_reset = false;
>  	}
> 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 */
diff mbox series

Patch

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..5123ec3fc74a 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -266,12 +266,14 @@  enum sdhci_reset_reason {
 	SDHCI_RESET_FOR_TUNING_ABORT,
 	SDHCI_RESET_FOR_CARD_REMOVED,
 	SDHCI_RESET_FOR_CQE_RECOVERY,
+	SDHCI_RESET_FOR_CMD_DAT_TOGETHER,
 };
 
 static void sdhci_reset_for_reason(struct sdhci_host *host, enum sdhci_reset_reason reason)
 {
 	switch (reason) {
 	case SDHCI_RESET_FOR_INIT:
+	case SDHCI_RESET_FOR_CMD_DAT_TOGETHER:
 		sdhci_do_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
 		break;
 	case SDHCI_RESET_FOR_REQUEST_ERROR:
@@ -3084,7 +3086,11 @@  static bool sdhci_request_done(struct sdhci_host *host)
 			/* This is to force an update */
 			host->ops->set_clock(host, host->clock);
 
-		sdhci_reset_for(host, REQUEST_ERROR);
+		if (host->quirks2 &
+			SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER)
+			sdhci_reset_for(host, CMD_DAT_TOGETHER);
+		else
+			sdhci_reset_for(host, REQUEST_ERROR);
 
 		host->pending_reset = false;
 	}
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 */