diff mbox series

[v1,2/3] scsi: ufs: add error handling of auto-hibern8

Message ID 1557758186-18706-3-git-send-email-stanley.chu@mediatek.com (mailing list archive)
State New, archived
Headers show
Series scsi: ufs: add error handlings of auto-hibern8 | expand

Commit Message

Stanley Chu May 13, 2019, 2:36 p.m. UTC
Currently auto-hibern8 is activated if host supports
auto-hibern8 capability. However no error handlings are existed thus
this feature is kind of risky.

If "Hibernate Enter" or "Hibernate Exit" fail happens
during auto-hibern8 flow, the corresponding interrupt
"UIC_HIBERNATE_ENTER" or "UIC_HIBERNATE_EXIT" shall be raised
according to UFS specification.

This patch adds auto-hibern8 error handlings:

- Monitor "Hibernate Enter" and "Hibernate Exit" interrupts after
  auto-hibern8 feature is activated.
- If fail happens, trigger error handlings just like "manual-hibernate"
  fail and use the same flow: Identify errors and 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>
---
 drivers/scsi/ufs/ufshcd.c | 14 ++++++++++++++
 drivers/scsi/ufs/ufshcd.h | 13 +++++++++++++
 drivers/scsi/ufs/ufshci.h |  3 +++
 3 files changed, 30 insertions(+)

Comments

Bean Huo May 13, 2019, 6:21 p.m. UTC | #1
Hi, Stanley

>+
>+static inline bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
>+						u32 intr_mask)
>+{
>+	return (ufshcd_is_auto_hibern8_supported(hba) &&
>+		!hba->uic_async_done &&

Here check if uic_async_done is NULL, no big problem so far, but not safe enough.
How about setting a flag in ufshcd_auto_hibern8_enable(),

I concern about how to compatible with auto_hibern8 disabled condition.


//Bean
Stanley Chu May 14, 2019, 6:58 a.m. UTC | #2
Hi Bean,

Thanks so much for review.

On Mon, 2019-05-13 at 18:21 +0000, Bean Huo (beanhuo) wrote:
> Hi, Stanley
> 
> >+
> >+static inline bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
> >+						u32 intr_mask)
> >+{
> >+	return (ufshcd_is_auto_hibern8_supported(hba) &&
> >+		!hba->uic_async_done &&
> 
> Here check if uic_async_done is NULL, no big problem so far, but not safe enough.
> How about setting a flag in ufshcd_auto_hibern8_enable(),

> 
> I concern about how to compatible with auto_hibern8 disabled condition.

Currently auto-hibern8 disabling method is not implemented in
mainstream, so an "enabling" flag may looks redundant unless disabling
path is really existed.

I agree that checking hba->uic_async_done here does not look so
intuitive. However even if auto-hibern8 is disabled, these checks could
be safe enough because both "UIC_HIBERNATE_ENTER" and
"UIC_HIBERNATE_EXIT" are raised only if "manual-hibernate" is performed,
and in this case hba->uic_async_done shall be true.

Anything else or corner case I missed?

> 
> 
> //Bean

Thanks,
Stanley

> 
> _______________________________________________
> Linux-mediatek mailing list
> Linux-mediatek@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-mediatek
Bean Huo May 14, 2019, 11:14 a.m. UTC | #3
Hi, Stanley
Thanks for reply.

>
>On Mon, 2019-05-13 at 18:21 +0000, Bean Huo (beanhuo) wrote:
>> Hi, Stanley
>>
>> >+
>> >+static inline bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
>> >+						u32 intr_mask)
>> >+{
>> >+	return (ufshcd_is_auto_hibern8_supported(hba) &&
>> >+		!hba->uic_async_done &&
>>
>> Here check if uic_async_done is NULL, no big problem so far, but not safe
>enough.
>> How about setting a flag in ufshcd_auto_hibern8_enable(),
>
>>
>> I concern about how to compatible with auto_hibern8 disabled condition.
>
>Currently auto-hibern8 disabling method is not implemented in mainstream,
>so an "enabling" flag may looks redundant unless disabling path is really
>existed.
>
Did you try to update Auto-Hibernate Idle Timer with 0 through '/sys'  (scsi: ufs: Add support for Auto-Hibernate Idle Timer)? 
I don't know if this will disable your UFS controller Auto-Hibernate.
If having a look at UFS host Spec, software writes “0” to disable Auto-Hibernate Idle Timer.
Sorry I cannot verify this on my platform since it doesn't support auto-hibernate.


>I agree that checking hba->uic_async_done here does not look so intuitive.
>However even if auto-hibern8 is disabled, these checks could be safe enough
>because both "UIC_HIBERNATE_ENTER" and "UIC_HIBERNATE_EXIT" are
>raised only if "manual-hibernate" is performed, and in this case hba-
>>uic_async_done shall be true.
>
Yes, most of cases ,this is no problem.

>Anything else or corner case I missed?
>
The others are fine. I only concern checking hba->uic_async_done.

//Bean
Stanley Chu May 15, 2019, 2:52 a.m. UTC | #4
Hi Bean,

On Tue, 2019-05-14 at 11:14 +0000, Bean Huo (beanhuo) wrote:
> Hi, Stanley
> Thanks for reply.
> 
> >
> >On Mon, 2019-05-13 at 18:21 +0000, Bean Huo (beanhuo) wrote:
> >> Hi, Stanley
> >>
> >> >+
> >> >+static inline bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
> >> >+						u32 intr_mask)
> >> >+{
> >> >+	return (ufshcd_is_auto_hibern8_supported(hba) &&
> >> >+		!hba->uic_async_done &&
> >>
> >> Here check if uic_async_done is NULL, no big problem so far, but not safe
> >enough.
> >> How about setting a flag in ufshcd_auto_hibern8_enable(),
> >
> >>
> >> I concern about how to compatible with auto_hibern8 disabled condition.
> >
> >Currently auto-hibern8 disabling method is not implemented in mainstream,
> >so an "enabling" flag may looks redundant unless disabling path is really
> >existed.
> >
> Did you try to update Auto-Hibernate Idle Timer with 0 through '/sys'  (scsi: ufs: Add support for Auto-Hibernate Idle Timer)? 
> I don't know if this will disable your UFS controller Auto-Hibernate.
> If having a look at UFS host Spec, software writes “0” to disable Auto-Hibernate Idle Timer.
> Sorry I cannot verify this on my platform since it doesn't support auto-hibernate.
> 

Sorry I missed this /sys interface for Auto-Hibernate control.

Yes, I have tested "Auto-Hibernate disabled" case, in this case,
UIC_HIBERNATE_ENTER and UIC_HIBERNATE_EXIT interrupts comes only if
Manual-Hibernate is performed and waiting for completion. Both
interrupts will not be identified as Auto-Hibernate errors by checking
hba->uic_async_done.

As for your concerning, I would like to make "Auto-Hibernate error
detection" more precise in next version: Use below conditions instead of
checking hba->uic_async_done:

As-is:

static inline bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
						u32 intr_mask)
{
	return (ufshcd_is_auto_hibern8_supported(hba) &&
		!hba->uic_async_done &&
		(intr_mask & UFSHCD_UIC_AH8_ERROR_MASK));
}

To-be:

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_AH8_ERROR_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;
}

What would you think about this change?

> 
> >I agree that checking hba->uic_async_done here does not look so intuitive.
> >However even if auto-hibern8 is disabled, these checks could be safe enough
> >because both "UIC_HIBERNATE_ENTER" and "UIC_HIBERNATE_EXIT" are
> >raised only if "manual-hibernate" is performed, and in this case hba-
> >>uic_async_done shall be true.
> >
> Yes, most of cases ,this is no problem.
> 
> >Anything else or corner case I missed?
> >
> The others are fine. I only concern checking hba->uic_async_done.
> 
> //Bean

Many thanks,
Stanley
diff mbox series

Patch

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1665820c22fd..e0e3930abc19 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) ||
+	    ufshcd_is_auto_hibern8_error(hba, hba->saved_err) ||
 	    ((hba->saved_err & UIC_ERROR) &&
 	    (hba->saved_uic_err & (UFSHCD_UIC_DL_PA_INIT_ERROR |
 				   UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
@@ -5431,6 +5432,15 @@  static void ufshcd_check_errors(struct ufs_hba *hba)
 			queue_eh_work = true;
 	}
 
+	if (ufshcd_is_auto_hibern8_error(hba, hba->errors)) {
+		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 +5503,10 @@  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_AH8_ERROR_MASK & intr_status);
+
 	if (hba->errors)
 		ufshcd_check_errors(hba);
 
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index ecfa898b9ccc..1bd9c8b61ed2 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -740,6 +740,19 @@  return true;
 #endif
 }
 
+static inline bool ufshcd_is_auto_hibern8_supported(struct ufs_hba *hba)
+{
+	return (hba->capabilities & MASK_AUTO_HIBERN8_SUPPORT);
+}
+
+static inline bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba,
+						u32 intr_mask)
+{
+	return (ufshcd_is_auto_hibern8_supported(hba) &&
+		!hba->uic_async_done &&
+		(intr_mask & UFSHCD_UIC_AH8_ERROR_MASK));
+}
+
 #define ufshcd_writel(hba, val, reg)	\
 	writel((val), (hba)->mmio_base + (reg))
 #define ufshcd_readl(hba, reg)	\
diff --git a/drivers/scsi/ufs/ufshci.h b/drivers/scsi/ufs/ufshci.h
index 6fa889de5ee5..4bcb205f2077 100644
--- a/drivers/scsi/ufs/ufshci.h
+++ b/drivers/scsi/ufs/ufshci.h
@@ -148,6 +148,9 @@  enum {
 				UIC_HIBERNATE_EXIT |\
 				UIC_POWER_MODE)
 
+#define UFSHCD_UIC_AH8_ERROR_MASK	(UIC_HIBERNATE_ENTER |\
+					UIC_HIBERNATE_EXIT)
+
 #define UFSHCD_UIC_MASK		(UIC_COMMAND_COMPL | UFSHCD_UIC_PWR_MASK)
 
 #define UFSHCD_ERROR_MASK	(UIC_ERROR |\