[PATCH 3/5] scsi: ufs: enable thermal exception event

[Avi Shchislowski]

From: Avi Shchislowski <avi.shchislowski@xxxxxxxxxxx>

The host might need to be aware of the device's temperature, when it's
too high or too low. Should such event occur, the device is expected
to notify it to the host by using the exception event mechanism.

E.g. when TOO_HIGH_TEMP in wExceptionEventStatus is raised, it is
recommended to perform thermal throttling or other cooling activities
for lowering the device Tcase temperature. Similarly, when
TOO_LOW_TEMP is raised, it is recommended to take an applicable
actions to increase the deviceâs Tcase temperature.

Signed-off-by: Uri Yanai <uri.yanai@xxxxxxx>
Signed-off-by: Avi Shchislowski <avi.shchislowski@xxxxxxxxxxx>
---
 drivers/scsi/ufs/ufs-thermal.c | 28 ++++++++++++++++++++++++----
 drivers/scsi/ufs/ufs-thermal.h |  6 ++++++
 drivers/scsi/ufs/ufs.h         |  6 +++++-
 drivers/scsi/ufs/ufshcd.c      |  4 ++++
 4 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-thermal.c b/drivers/scsi/ufs/ufs-thermal.c
index 469c1ed..dfa5d68 100644
--- a/drivers/scsi/ufs/ufs-thermal.c
+++ b/drivers/scsi/ufs/ufs-thermal.c
@@ -19,11 +19,32 @@ enum {
 
 /**
  *struct ufs_thermal - thermal zone related data
- * @tzone: thermal zone device data
+ * @trip: trip array
  */
 static struct ufs_thermal {
 	struct thermal_zone_device *zone;
-} thermal;
+	int trip[UFS_THERM_MAX_TRIPS];
+} thermal = {
+		.trip = {
+			[UFS_THERM_MAX_TEMP] = 170 * 1000,
+			[UFS_THERM_MIN_TEMP] = -79 * 1000
+		}
+};
+
+void ufs_thermal_exception_event_handler(struct ufs_hba *hba,
+		u32 exception_status)
+{
+	if (WARN_ON_ONCE(!hba->thermal_features))
+		return;
+
+	if (exception_status & MASK_EE_TOO_HIGH_TEMP) {
+		thermal_notify_framework(thermal.zone, UFS_THERM_HIGH_TEMP);
+		dev_info(hba->dev, "High temperature raised\n");
+	} else if (exception_status & MASK_EE_TOO_LOW_TEMP) {
+		thermal_notify_framework(thermal.zone, UFS_THERM_LOW_TEMP);
+		dev_info(hba->dev, "Low temperature raised\n");
+	}
+}
 
 static  struct thermal_zone_device_ops ufs_thermal_ops = {
 	.get_temp = NULL,
@@ -33,8 +54,7 @@ enum {
 
 static int ufs_thermal_enable_ee(struct ufs_hba *hba)
 {
-	/* later */
-	return -EINVAL;
+	return ufshcd_enable_ee(hba, MASK_EE_URGENT_TEMP);
 }
 
 static void ufs_thermal_zone_unregister(struct ufs_hba *hba)
diff --git a/drivers/scsi/ufs/ufs-thermal.h b/drivers/scsi/ufs/ufs-thermal.h
index 7c0fcbe..285049e 100644
--- a/drivers/scsi/ufs/ufs-thermal.h
+++ b/drivers/scsi/ufs/ufs-thermal.h
@@ -11,9 +11,15 @@
 #ifdef CONFIG_THERMAL_UFS
 void ufs_thermal_remove(struct ufs_hba *hba);
 int ufs_thermal_probe(struct ufs_hba *hba);
+void ufs_thermal_exception_event_handler(struct ufs_hba *hba,
+		u32 exception_status);
 #else
 static inline void ufs_thermal_remove(struct ufs_hba *hba) {}
 static inline int ufs_thermal_probe(struct ufs_hba *hba) {return 0; }
+void ufs_thermal_exception_event_handler(struct ufs_hba *hba,
+		u32 exception_status)
+{
+}
 #endif /* CONFIG_THERMAL_UFS */
 
 #endif /* UFS_THERMAL_H */
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index eb729cc..8fc0b0c 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -363,7 +363,9 @@ enum power_desc_param_offset {
 /* Exception event mask values */
 enum {
 	MASK_EE_STATUS		= 0xFFFF,
-	MASK_EE_URGENT_BKOPS	= (1 << 2),
+	MASK_EE_URGENT_BKOPS	= BIT(2),
+	MASK_EE_TOO_HIGH_TEMP	= BIT(3),
+	MASK_EE_TOO_LOW_TEMP	= BIT(4),
 };
 
 /* Background operation status */
@@ -375,6 +377,8 @@ enum bkops_status {
 	BKOPS_STATUS_MAX		 = BKOPS_STATUS_CRITICAL,
 };
 
+#define MASK_EE_URGENT_TEMP (MASK_EE_TOO_HIGH_TEMP | MASK_EE_TOO_LOW_TEMP)
+
 /* UTP QUERY Transaction Specific Fields OpCode */
 enum query_opcode {
 	UPIU_QUERY_OPCODE_NOP		= 0x0,
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index f25b93c..45fb52d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -42,6 +42,7 @@
 #include <linux/nls.h>
 #include <linux/of.h>
 #include <linux/bitfield.h>
+#include <linux/thermal.h>
 #include "ufshcd.h"
 #include "ufs_quirks.h"
 #include "unipro.h"
@@ -5183,6 +5184,9 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 	if (status & MASK_EE_URGENT_BKOPS)
 		ufshcd_bkops_exception_event_handler(hba);
 
+	if (status & MASK_EE_URGENT_TEMP)
+		ufs_thermal_exception_event_handler(hba, status);
+
 out:
 	ufshcd_scsi_unblock_requests(hba);
 	pm_runtime_put_sync(hba->dev);
-- 
1.9.1