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* [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate
@ 2019-05-21  6:44 Stanley Chu
  2019-05-21  6:44 ` [PATCH v5 1/3] scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported() Stanley Chu
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Stanley Chu @ 2019-05-21  6:44 UTC (permalink / raw)
  To: linux-scsi, martin.petersen, avri.altman, alim.akhtar, pedrom.sousa
  Cc: marc.w.gonzalez, andy.teng, chun-hung.wu, kuohong.wang, evgreen,
	linux-mediatek, peter.wang, matthias.bgg, Stanley Chu,
	linux-arm-kernel, beanhuo

Currently auto-hibernate is activated if host supports
auto-hibern8 capability. However error-handling is not implemented,
which makes the feature somewhat risky.

If either "Hibernate Enter" or "Hibernate Exit" fail during
auto-hibernate flow, the corresponding interrupt
"UIC_HIBERNATE_ENTER" or "UIC_HIBERNATE_EXIT" shall be raised
according to UFS specification.

This patch adds auto-hibernate error-handling:

- Monitor "Hibernate Enter" and "Hibernate Exit" interrupts after
  auto-hibernate feature is activated.

- If fail happens, trigger error-handling just like "manual-hibernate"
  fail and apply the same recovery flow: schedule UFS error handler in
  ufshcd_check_errors(), and then do host reset and restore
  in UFS error handler.

v5:
 - Also re-factor checking of Auto-Hibernation support in other places, e.g., in ufshcd_auto_hibern8_enable() and in ufs-sysfs (Avri Altman)
 - Change order of patch "scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported()" to #1 as a preparation patch of whole series

v4:
 - Replace original patch "[3/3] scsi: ufs: Use re-factored Auto-Hibernate function" by a new preparation patch "[2/3] scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported()" for re-factoring ufshcd_is_auto_hibern8_supported (Avri Altman)
 - Refine UIC mask definitions (Avri Altman)

v3:
 - Fix typo in patch "scsi: ufs: Do not overwrite Auto-Hibernate timer" (Avri Altman)
 - Rebase to Linux 5.2-rc1

v2:
 - Fix sentences in commit message (Marc Gonzalez)
 - Make "Auto-Hibernate" error detection more precise (Bean Huo)

Stanley Chu (3):
  scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported()
  scsi: ufs: Do not overwrite Auto-Hibernate timer
  scsi: ufs: Add error-handling of Auto-Hibernate

 drivers/scsi/ufs/ufs-sysfs.c |  6 +++---
 drivers/scsi/ufs/ufshcd.c    | 35 +++++++++++++++++++++++++++++++++--
 drivers/scsi/ufs/ufshcd.h    |  5 +++++
 drivers/scsi/ufs/ufshci.h    |  6 ++++--
 4 files changed, 45 insertions(+), 7 deletions(-)

-- 
2.18.0


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^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v5 1/3] scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported()
  2019-05-21  6:44 [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate Stanley Chu
@ 2019-05-21  6:44 ` Stanley Chu
  2019-05-21  6:44 ` [PATCH v5 2/3] scsi: ufs: Do not overwrite Auto-Hibernate timer Stanley Chu
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Stanley Chu @ 2019-05-21  6:44 UTC (permalink / raw)
  To: linux-scsi, martin.petersen, avri.altman, alim.akhtar, pedrom.sousa
  Cc: marc.w.gonzalez, andy.teng, chun-hung.wu, kuohong.wang, evgreen,
	linux-mediatek, peter.wang, matthias.bgg, Stanley Chu,
	linux-arm-kernel, beanhuo

The checking of Auto-Hibernation support is used in
many places in the driver, thus re-factor it as
ufshcd_is_auto_hibern8_supported() to make code more
clean.

Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
---
 drivers/scsi/ufs/ufs-sysfs.c | 6 +++---
 drivers/scsi/ufs/ufshcd.c    | 4 ++--
 drivers/scsi/ufs/ufshcd.h    | 5 +++++
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index 8d9332bb7d0c..f478685122ff 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -122,7 +122,7 @@ static void ufshcd_auto_hibern8_update(struct ufs_hba *hba, u32 ahit)
 {
 	unsigned long flags;
 
-	if (!(hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT))
+	if (!ufshcd_is_auto_hibern8_supported(hba))
 		return;
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
@@ -164,7 +164,7 @@ static ssize_t auto_hibern8_show(struct device *dev,
 {
 	struct ufs_hba *hba = dev_get_drvdata(dev);
 
-	if (!(hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT))
+	if (!ufshcd_is_auto_hibern8_supported(hba))
 		return -EOPNOTSUPP;
 
 	return snprintf(buf, PAGE_SIZE, "%d\n", ufshcd_ahit_to_us(hba->ahit));
@@ -177,7 +177,7 @@ static ssize_t auto_hibern8_store(struct device *dev,
 	struct ufs_hba *hba = dev_get_drvdata(dev);
 	unsigned int timer;
 
-	if (!(hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT))
+	if (!ufshcd_is_auto_hibern8_supported(hba))
 		return -EOPNOTSUPP;
 
 	if (kstrtouint(buf, 0, &timer))
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 8c1c551f2b42..0cf698d05426 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3907,7 +3907,7 @@ static void ufshcd_auto_hibern8_enable(struct ufs_hba *hba)
 {
 	unsigned long flags;
 
-	if (!(hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT) || !hba->ahit)
+	if (!ufshcd_is_auto_hibern8_supported(hba) || !hba->ahit)
 		return;
 
 	spin_lock_irqsave(hba->host->host_lock, flags);
@@ -8312,7 +8312,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 						UIC_LINK_HIBERN8_STATE);
 
 	/* Set the default auto-hiberate idle timer value to 150 ms */
-	if (hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT) {
+	if (ufshcd_is_auto_hibern8_supported(hba)) {
 		hba->ahit = FIELD_PREP(UFSHCI_AHIBERN8_TIMER_MASK, 150) |
 			    FIELD_PREP(UFSHCI_AHIBERN8_SCALE_MASK, 3);
 	}
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index ecfa898b9ccc..994d73d03207 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -740,6 +740,11 @@ return true;
 #endif
 }
 
+static inline bool ufshcd_is_auto_hibern8_supported(struct ufs_hba *hba)
+{
+	return (hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT);
+}
+
 #define ufshcd_writel(hba, val, reg)	\
 	writel((val), (hba)->mmio_base + (reg))
 #define ufshcd_readl(hba, reg)	\
-- 
2.18.0


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^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v5 2/3] scsi: ufs: Do not overwrite Auto-Hibernate timer
  2019-05-21  6:44 [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate Stanley Chu
  2019-05-21  6:44 ` [PATCH v5 1/3] scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported() Stanley Chu
@ 2019-05-21  6:44 ` Stanley Chu
  2019-05-21  6:44 ` [PATCH v5 3/3] scsi: ufs: Add error-handling of Auto-Hibernate Stanley Chu
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Stanley Chu @ 2019-05-21  6:44 UTC (permalink / raw)
  To: linux-scsi, martin.petersen, avri.altman, alim.akhtar, pedrom.sousa
  Cc: marc.w.gonzalez, andy.teng, chun-hung.wu, kuohong.wang, evgreen,
	linux-mediatek, peter.wang, matthias.bgg, Stanley Chu,
	linux-arm-kernel, beanhuo

Some vendor-specific initialization flow may set its own
auto-hibernate timer. In this case, do not overwrite timer value
as "default value" in ufshcd_init().

Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
---
 drivers/scsi/ufs/ufshcd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 0cf698d05426..7cd757558203 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -8312,7 +8312,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 						UIC_LINK_HIBERN8_STATE);
 
 	/* Set the default auto-hiberate idle timer value to 150 ms */
-	if (ufshcd_is_auto_hibern8_supported(hba)) {
+	if (ufshcd_is_auto_hibern8_supported(hba) && !hba->ahit) {
 		hba->ahit = FIELD_PREP(UFSHCI_AHIBERN8_TIMER_MASK, 150) |
 			    FIELD_PREP(UFSHCI_AHIBERN8_SCALE_MASK, 3);
 	}
-- 
2.18.0


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^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v5 3/3] scsi: ufs: Add error-handling of Auto-Hibernate
  2019-05-21  6:44 [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate Stanley Chu
  2019-05-21  6:44 ` [PATCH v5 1/3] scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported() Stanley Chu
  2019-05-21  6:44 ` [PATCH v5 2/3] scsi: ufs: Do not overwrite Auto-Hibernate timer Stanley Chu
@ 2019-05-21  6:44 ` Stanley Chu
  2019-05-21  8:41 ` [PATCH v5 0/3] scsi: ufs: Add error handling " Avri Altman
  2019-05-30  2:19 ` Martin K. Petersen
  4 siblings, 0 replies; 6+ messages in thread
From: Stanley Chu @ 2019-05-21  6:44 UTC (permalink / raw)
  To: linux-scsi, martin.petersen, avri.altman, alim.akhtar, pedrom.sousa
  Cc: marc.w.gonzalez, andy.teng, chun-hung.wu, kuohong.wang, evgreen,
	linux-mediatek, peter.wang, matthias.bgg, Stanley Chu,
	linux-arm-kernel, beanhuo

Currently auto-hibernate is activated if host supports
auto-hibern8 capability. However error-handling is not implemented,
which makes the feature somewhat risky.

If either "Hibernate Enter" or "Hibernate Exit" fail during
auto-hibernate flow, the corresponding interrupt
"UIC_HIBERNATE_ENTER" or "UIC_HIBERNATE_EXIT" shall be raised
according to UFS specification.

This patch adds auto-hibernate error-handling:

- Monitor "Hibernate Enter" and "Hibernate Exit" interrupts after
  auto-hibernate feature is activated.

- If fail happens, trigger error-handling just like "manual-hibernate"
  fail and apply the same recovery flow: schedule UFS error handler in
  ufshcd_check_errors(), and then do host reset and restore
  in UFS error handler.

Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
---
 drivers/scsi/ufs/ufshcd.c | 31 +++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshci.h |  6 ++++--
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 7cd757558203..a208589426b1 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5254,6 +5254,7 @@ static void ufshcd_err_handler(struct work_struct *work)
 			goto skip_err_handling;
 	}
 	if ((hba->saved_err & INT_FATAL_ERRORS) ||
+	    (hba->saved_err & UFSHCD_UIC_HIBERN8_MASK) ||
 	    ((hba->saved_err & UIC_ERROR) &&
 	    (hba->saved_uic_err & (UFSHCD_UIC_DL_PA_INIT_ERROR |
 				   UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
@@ -5413,6 +5414,23 @@ static void ufshcd_update_uic_error(struct ufs_hba *hba)
 			__func__, hba->uic_error);
 }
 
+static bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
+					 u32 intr_mask)
+{
+	if (!ufshcd_is_auto_hibern8_supported(hba))
+		return false;
+
+	if (!(intr_mask & UFSHCD_UIC_HIBERN8_MASK))
+		return false;
+
+	if (hba->active_uic_cmd &&
+	    (hba->active_uic_cmd->command == UIC_CMD_DME_HIBER_ENTER ||
+	    hba->active_uic_cmd->command == UIC_CMD_DME_HIBER_EXIT))
+		return false;
+
+	return true;
+}
+
 /**
  * ufshcd_check_errors - Check for errors that need s/w attention
  * @hba: per-adapter instance
@@ -5431,6 +5449,15 @@ static void ufshcd_check_errors(struct ufs_hba *hba)
 			queue_eh_work = true;
 	}
 
+	if (hba->errors & UFSHCD_UIC_HIBERN8_MASK) {
+		dev_err(hba->dev,
+			"%s: Auto Hibern8 %s failed - status: 0x%08x, upmcrs: 0x%08x\n",
+			__func__, (hba->errors & UIC_HIBERNATE_ENTER) ?
+			"Enter" : "Exit",
+			hba->errors, ufshcd_get_upmcrs(hba));
+		queue_eh_work = true;
+	}
+
 	if (queue_eh_work) {
 		/*
 		 * update the transfer error masks to sticky bits, let's do this
@@ -5493,6 +5520,10 @@ static void ufshcd_tmc_handler(struct ufs_hba *hba)
 static void ufshcd_sl_intr(struct ufs_hba *hba, u32 intr_status)
 {
 	hba->errors = UFSHCD_ERROR_MASK & intr_status;
+
+	if (ufshcd_is_auto_hibern8_error(hba, intr_status))
+		hba->errors |= (UFSHCD_UIC_HIBERN8_MASK & intr_status);
+
 	if (hba->errors)
 		ufshcd_check_errors(hba);
 
diff --git a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h
index 6fa889de5ee5..dbb75cd28dc8 100644
--- a/drivers/scsi/ufs/ufshci.h
+++ b/drivers/scsi/ufs/ufshci.h
@@ -144,8 +144,10 @@ enum {
 #define CONTROLLER_FATAL_ERROR			0x10000
 #define SYSTEM_BUS_FATAL_ERROR			0x20000
 
-#define UFSHCD_UIC_PWR_MASK	(UIC_HIBERNATE_ENTER |\
-				UIC_HIBERNATE_EXIT |\
+#define UFSHCD_UIC_HIBERN8_MASK	(UIC_HIBERNATE_ENTER |\
+				UIC_HIBERNATE_EXIT)
+
+#define UFSHCD_UIC_PWR_MASK	(UFSHCD_UIC_HIBERN8_MASK |\
 				UIC_POWER_MODE)
 
 #define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL | UFSHCD_UIC_PWR_MASK)
-- 
2.18.0


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^ permalink raw reply related	[flat|nested] 6+ messages in thread

* RE: [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate
  2019-05-21  6:44 [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate Stanley Chu
                   ` (2 preceding siblings ...)
  2019-05-21  6:44 ` [PATCH v5 3/3] scsi: ufs: Add error-handling of Auto-Hibernate Stanley Chu
@ 2019-05-21  8:41 ` Avri Altman
  2019-05-30  2:19 ` Martin K. Petersen
  4 siblings, 0 replies; 6+ messages in thread
From: Avri Altman @ 2019-05-21  8:41 UTC (permalink / raw)
  To: Stanley Chu, linux-scsi, martin.petersen, alim.akhtar, pedrom.sousa
  Cc: marc.w.gonzalez, andy.teng, chun-hung.wu, kuohong.wang, evgreen,
	linux-mediatek, peter.wang, matthias.bgg, linux-arm-kernel,
	beanhuo

This series looks fine to me.

Thanks,
Avri

> 
> Currently auto-hibernate is activated if host supports
> auto-hibern8 capability. However error-handling is not implemented,
> which makes the feature somewhat risky.
> 
> If either "Hibernate Enter" or "Hibernate Exit" fail during
> auto-hibernate flow, the corresponding interrupt
> "UIC_HIBERNATE_ENTER" or "UIC_HIBERNATE_EXIT" shall be raised
> according to UFS specification.
> 
> This patch adds auto-hibernate error-handling:
> 
> - Monitor "Hibernate Enter" and "Hibernate Exit" interrupts after
>   auto-hibernate feature is activated.
> 
> - If fail happens, trigger error-handling just like "manual-hibernate"
>   fail and apply the same recovery flow: schedule UFS error handler in
>   ufshcd_check_errors(), and then do host reset and restore
>   in UFS error handler.
> 
> v5:
>  - Also re-factor checking of Auto-Hibernation support in other places, e.g., in
> ufshcd_auto_hibern8_enable() and in ufs-sysfs (Avri Altman)
>  - Change order of patch "scsi: ufs: Introduce
> ufshcd_is_auto_hibern8_supported()" to #1 as a preparation patch of whole
> series
> 
> v4:
>  - Replace original patch "[3/3] scsi: ufs: Use re-factored Auto-Hibernate
> function" by a new preparation patch "[2/3] scsi: ufs: Introduce
> ufshcd_is_auto_hibern8_supported()" for re-factoring
> ufshcd_is_auto_hibern8_supported (Avri Altman)
>  - Refine UIC mask definitions (Avri Altman)
> 
> v3:
>  - Fix typo in patch "scsi: ufs: Do not overwrite Auto-Hibernate timer" (Avri
> Altman)
>  - Rebase to Linux 5.2-rc1
> 
> v2:
>  - Fix sentences in commit message (Marc Gonzalez)
>  - Make "Auto-Hibernate" error detection more precise (Bean Huo)
> 
> Stanley Chu (3):
>   scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported()
>   scsi: ufs: Do not overwrite Auto-Hibernate timer
>   scsi: ufs: Add error-handling of Auto-Hibernate
> 
>  drivers/scsi/ufs/ufs-sysfs.c |  6 +++---
>  drivers/scsi/ufs/ufshcd.c    | 35 +++++++++++++++++++++++++++++++++--
>  drivers/scsi/ufs/ufshcd.h    |  5 +++++
>  drivers/scsi/ufs/ufshci.h    |  6 ++++--
>  4 files changed, 45 insertions(+), 7 deletions(-)
> 
> --
> 2.18.0


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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate
  2019-05-21  6:44 [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate Stanley Chu
                   ` (3 preceding siblings ...)
  2019-05-21  8:41 ` [PATCH v5 0/3] scsi: ufs: Add error handling " Avri Altman
@ 2019-05-30  2:19 ` Martin K. Petersen
  4 siblings, 0 replies; 6+ messages in thread
From: Martin K. Petersen @ 2019-05-30  2:19 UTC (permalink / raw)
  To: Stanley Chu
  Cc: linux-scsi, martin.petersen, marc.w.gonzalez, andy.teng,
	chun-hung.wu, kuohong.wang, evgreen, avri.altman, linux-mediatek,
	peter.wang, alim.akhtar, matthias.bgg, pedrom.sousa,
	linux-arm-kernel, beanhuo


Stanley,

> Currently auto-hibernate is activated if host supports auto-hibern8
> capability. However error-handling is not implemented, which makes the
> feature somewhat risky.

Applied to 5.3/scsi-queue, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

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^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2019-05-30  2:19 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-05-21  6:44 [PATCH v5 0/3] scsi: ufs: Add error handling of Auto-Hibernate Stanley Chu
2019-05-21  6:44 ` [PATCH v5 1/3] scsi: ufs: Introduce ufshcd_is_auto_hibern8_supported() Stanley Chu
2019-05-21  6:44 ` [PATCH v5 2/3] scsi: ufs: Do not overwrite Auto-Hibernate timer Stanley Chu
2019-05-21  6:44 ` [PATCH v5 3/3] scsi: ufs: Add error-handling of Auto-Hibernate Stanley Chu
2019-05-21  8:41 ` [PATCH v5 0/3] scsi: ufs: Add error handling " Avri Altman
2019-05-30  2:19 ` Martin K. Petersen

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