[PATCH v3] scsi: ufs: Fix hynix ufs bug with quirk on hi36xx SoC

[PATCH v3] scsi: ufs: Fix hynix ufs bug with quirk on hi36xx SoC

[John Stultz]

From: Wei Li <liwei213@huawei.com>

Hynix ufs has deviations on hi36xx platform which will result in
ufs bursts transfer failures.

To fix the problem, the Hynix device must set the register
VS_DebugSaveConfigTime to 0x10, which will set time reference
for SaveConfigTime is 250 ns. The time reference for SaveConfigTime
is 40 ns by default.

This patch is necessary to boot on HiKey960 boards that use
Hynix UFS chips (H28U62301AMR model: hB8aL1).

Cc: Vinayak Holikatti <vinholikatti@gmail.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Wei Li <liwei213@huawei.com>
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
[jstultz: Forward ported from older code, slight tweak to commit message]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
v2:
* Narrowed the UFS chip model to the specific model where
  the issue has been seen. (SKhynix  H28U62301AMR model: hB8aL1)
* Reworked logic to be contained in ufs-hisi.c since it seems to
  be a controller issue that crops up with this specific chip
v3:
* Reworked back to using generic hba quriks which we then key on
  in the hisi driver.
---
 drivers/scsi/ufs/ufs-hisi.c   | 9 +++++++++
 drivers/scsi/ufs/ufs_quirks.h | 6 ++++++
 drivers/scsi/ufs/ufshcd.c     | 2 ++
 3 files changed, 17 insertions(+)

diff --git a/drivers/scsi/ufs/ufs-hisi.c b/drivers/scsi/ufs/ufs-hisi.c
index 46df707..452e19f 100644
--- a/drivers/scsi/ufs/ufs-hisi.c
+++ b/drivers/scsi/ufs/ufs-hisi.c
@@ -20,6 +20,7 @@
 #include "unipro.h"
 #include "ufs-hisi.h"
 #include "ufshci.h"
+#include "ufs_quirks.h"
 
 static int ufs_hisi_check_hibern8(struct ufs_hba *hba)
 {
@@ -390,6 +391,14 @@ static void ufs_hisi_set_dev_cap(struct ufs_hisi_dev_params *hisi_param)
 
 static void ufs_hisi_pwr_change_pre_change(struct ufs_hba *hba)
 {
+	if (hba->dev_quirks & UFS_DEVICE_QUIRK_HOST_VS_DEBUGSAVECONFIGTIME) {
+		pr_info("ufs flash device must set VS_DebugSaveConfigTime 0x10\n");
+		/* VS_DebugSaveConfigTime */
+		ufshcd_dme_set(hba, UIC_ARG_MIB(0xD0A0), 0x10);
+		/* sync length */
+		ufshcd_dme_set(hba, UIC_ARG_MIB(0x1556), 0x48);
+	}
+
 	/* update */
 	ufshcd_dme_set(hba, UIC_ARG_MIB(0x15A8), 0x1);
 	/* PA_TxSkip */
diff --git a/drivers/scsi/ufs/ufs_quirks.h b/drivers/scsi/ufs/ufs_quirks.h
index 71f73d1..5d2dfdb 100644
--- a/drivers/scsi/ufs/ufs_quirks.h
+++ b/drivers/scsi/ufs/ufs_quirks.h
@@ -131,4 +131,10 @@ struct ufs_dev_fix {
  */
 #define UFS_DEVICE_QUIRK_HOST_PA_SAVECONFIGTIME	(1 << 8)
 
+/*
+ * Some UFS devices require VS_DebugSaveConfigTime is 0x10,
+ * enabling this quirk ensure this.
+ */
+#define UFS_DEVICE_QUIRK_HOST_VS_DEBUGSAVECONFIGTIME	(1 << 9)
+
 #endif /* UFS_QUIRKS_H_ */
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c55f38e..9c6cac9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -230,6 +230,8 @@ static struct ufs_dev_fix ufs_fixups[] = {
 	UFS_FIX(UFS_VENDOR_SKHYNIX, UFS_ANY_MODEL, UFS_DEVICE_NO_VCCQ),
 	UFS_FIX(UFS_VENDOR_SKHYNIX, UFS_ANY_MODEL,
 		UFS_DEVICE_QUIRK_HOST_PA_SAVECONFIGTIME),
+	UFS_FIX(UFS_VENDOR_SKHYNIX, "hB8aL1" /*H28U62301AMR*/,
+		UFS_DEVICE_QUIRK_HOST_VS_DEBUGSAVECONFIGTIME),
 
 	END_FIX
 };
-- 
2.7.4