[PATCH v6 0/6] Several changes for UFS WriteBooster

[PATCH v6 0/6] Several changes for UFS WriteBooster

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

Changelog:

v5--v6:
 1. Remove original patch 7/7:
 "scsi: ufs: Keep device active mode only fWriteBoosterBufferFlushDuringHibernate == 1"
 2. Rebased patch onto 5.12/scsi-staging
 3. Add protection of PM ops and err_handler for the wb_on entry access

V4--V5:
  1. Add patch "docs: ABI: Add wb_on documentation for UFS sysfs"
  2. Unify WB related flags with wb_* prefix (Stanley Chu)
  3. Delete d_ext_ufs_feature_sup (Stanley Chu)
  4. Incorporate Stanley's suggestion to patch 6/7
  5. Replace scnprintf() with sysfs_emit() in 1/7 (Greg KH)

v3--v4:
  1. Rebase patch on 5.11/scsi-staging
  2. Add WB cleanup patches 3/6, 4/6 adn 5/6

v2--v3:
  1. Change multi-line comments style in patch 1/3 (Can Guo)

v1--v2:
  1. Take is_hibern8_wb_flush checkup out from function
     ufshcd_wb_need_flush() in patch 2/3
  2. Add UFSHCD_CAP_CLK_SCALING checkup in patch 1/3. that means
     only for the platform, which doesn't support UFSHCD_CAP_CLK_SCALING,
     can control WB through "wb_on".

Bean Huo (6):
  scsi: ufs: Add "wb_on" sysfs node to control WB on/off
  docs: ABI: Add wb_on documentation for UFS sysfs
  scsi: ufs: Changes comment in the function ufshcd_wb_probe()
  scsi: ufs: Remove two WB related fields from struct ufs_dev_info
  scsi: ufs: Group UFS WB related flags to struct ufs_dev_info
  scsi: ufs: Cleanup WB buffer flush toggle implementation

 Documentation/ABI/testing/sysfs-driver-ufs |   8 ++
 drivers/scsi/ufs/ufs-sysfs.c               |  46 +++++++++
 drivers/scsi/ufs/ufs.h                     |  29 +++---
 drivers/scsi/ufs/ufshcd.c                  | 103 ++++++++-------------
 drivers/scsi/ufs/ufshcd.h                  |   6 +-
 5 files changed, 110 insertions(+), 82 deletions(-)

-- 
2.17.1

[PATCH v6 1/6] scsi: ufs: Add "wb_on" sysfs node to control WB on/off

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

Currently UFS WriteBooster driver uses clock scaling up/down to set
WB on/off, for the platform which doesn't support UFSHCD_CAP_CLK_SCALING,
WB will be always on. Provide a sysfs attribute to enable/disable WB
during runtime. Write 1/0 to "wb_on" sysfs node to enable/disable UFS WB.

Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufs-sysfs.c | 46 ++++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufshcd.c    |  3 +--
 drivers/scsi/ufs/ufshcd.h    |  2 ++
 3 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index c092f249d6f9..76db8593ca09 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -209,6 +209,50 @@ static ssize_t auto_hibern8_store(struct device *dev,
 	return ret ? ret : count;
 }
 
+static ssize_t wb_on_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%d\n", hba->wb_enabled);
+}
+
+static ssize_t wb_on_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
+{
+	struct ufs_hba *hba = dev_get_drvdata(dev);
+	unsigned int wb_enable;
+	ssize_t res;
+
+	if (!ufshcd_is_wb_allowed(hba) || ufshcd_is_clkscaling_supported(hba)) {
+		/*
+		 * If the platform supports UFSHCD_CAP_CLK_SCALING, turn WB
+		 * on/off will be done while clock scaling up/down.
+		 */
+		dev_warn(dev, "To control WB through wb_on is not allowed!\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (kstrtouint(buf, 0, &wb_enable))
+		return -EINVAL;
+
+	if (wb_enable != 0 && wb_enable != 1)
+		return -EINVAL;
+
+	down(&hba->host_sem);
+	if (!ufshcd_is_user_access_allowed(hba)) {
+		res = -EBUSY;
+		goto out;
+	}
+
+	pm_runtime_get_sync(hba->dev);
+	res = ufshcd_wb_ctrl(hba, wb_enable);
+	pm_runtime_put_sync(hba->dev);
+out:
+	up(&hba->host_sem);
+	return res < 0 ? res : count;
+}
+
 static DEVICE_ATTR_RW(rpm_lvl);
 static DEVICE_ATTR_RO(rpm_target_dev_state);
 static DEVICE_ATTR_RO(rpm_target_link_state);
@@ -216,6 +260,7 @@ static DEVICE_ATTR_RW(spm_lvl);
 static DEVICE_ATTR_RO(spm_target_dev_state);
 static DEVICE_ATTR_RO(spm_target_link_state);
 static DEVICE_ATTR_RW(auto_hibern8);
+static DEVICE_ATTR_RW(wb_on);
 
 static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
 	&dev_attr_rpm_lvl.attr,
@@ -225,6 +270,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
 	&dev_attr_spm_target_dev_state.attr,
 	&dev_attr_spm_target_link_state.attr,
 	&dev_attr_auto_hibern8.attr,
+	&dev_attr_wb_on.attr,
 	NULL
 };
 
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 5c6ee9394af3..3f2b495b36ee 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -249,7 +249,6 @@ static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
 static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag);
 static int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba);
 static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba);
-static int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable);
 static int ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set);
 static inline void ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable);
 static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba);
@@ -5413,7 +5412,7 @@ static void ufshcd_bkops_exception_event_handler(struct ufs_hba *hba)
 				__func__, err);
 }
 
-static int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable)
+int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable)
 {
 	int ret;
 	u8 index;
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 5bbe4715d4e9..ac0f03f69e42 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -1089,6 +1089,8 @@ int ufshcd_exec_raw_upiu_cmd(struct ufs_hba *hba,
 			     u8 *desc_buff, int *buff_len,
 			     enum query_opcode desc_op);
 
+int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable);
+
 /* Wrapper functions for safely calling variant operations */
 static inline const char *ufshcd_get_var_name(struct ufs_hba *hba)
 {
-- 
2.17.1

[PATCH v6 2/6] docs: ABI: Add wb_on documentation for UFS sysfs

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

Adds UFS sysfs documentation for new entry wb_on.

Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 Documentation/ABI/testing/sysfs-driver-ufs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-driver-ufs b/Documentation/ABI/testing/sysfs-driver-ufs
index adc0d0e91607..f0a1ac385c7f 100644
--- a/Documentation/ABI/testing/sysfs-driver-ufs
+++ b/Documentation/ABI/testing/sysfs-driver-ufs
@@ -1153,3 +1153,11 @@ Description:	This entry shows the configured size of WriteBooster buffer.
 		0400h corresponds to 4GB.
 
 		The file is read only.
+
+What:		/sys/bus/platform/drivers/ufshcd/*/wb_on
+Date:		January 2021
+Contact:	Bean Huo <beanhuo@micron.com>
+Description:	This node is used to set or display whether UFS WriteBooster is
+        enabled. Echo 0 to this file to disable UFS WriteBooster or 1 to enable
+        it. Note, this is only allowed for the platform doesen't support
+        UFSHCD_CAP_CLK_SCALING.
-- 
2.17.1

[PATCH v6 3/6] scsi: ufs: Changes comment in the function ufshcd_wb_probe()

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

USFHCD supports WriteBooster "LU dedicated buffer” mode and
“shared buffer” mode both, so changes the comment in the
function ufshcd_wb_probe().

Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufshcd.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 3f2b495b36ee..a3758fd83ebd 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7294,10 +7294,9 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 		goto wb_disabled;
 
 	/*
-	 * WB may be supported but not configured while provisioning.
-	 * The spec says, in dedicated wb buffer mode,
-	 * a max of 1 lun would have wb buffer configured.
-	 * Now only shared buffer mode is supported.
+	 * WB may be supported but not configured while provisioning. The spec
+	 * says, in dedicated wb buffer mode, a max of 1 lun would have wb
+	 * buffer configured.
 	 */
 	dev_info->b_wb_buffer_type =
 		desc_buf[DEVICE_DESC_PARAM_WB_TYPE];
-- 
2.17.1

[PATCH v6 4/6] scsi: ufs: Remove two WB related fields from struct ufs_dev_info

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

d_wb_alloc_units and d_ext_ufs_feature_sup only be used while WB probe.
They are just used to confirm the condition that "if bWriteBoosterBufferType
is set to 01h but dNumSharedWriteBoosterBufferAllocUnits is set to zero,
the WriteBooster feature is disabled", and if UFS device supports WB.
After that, no user uses them any more. So, don't need to keep time in
runtime.

Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufs.h    |  2 --
 drivers/scsi/ufs/ufshcd.c | 14 ++++++--------
 2 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 09c7cc8a678d..a8000ed0017e 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -538,9 +538,7 @@ struct ufs_dev_info {
 	u8 *model;
 	u16 wspecversion;
 	u32 clk_gating_wait_us;
-	u32 d_ext_ufs_feature_sup;
 	u8 b_wb_buffer_type;
-	u32 d_wb_alloc_units;
 	bool b_rpm_dev_flush_capable;
 	u8 b_presrv_uspc_en;
 };
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index a3758fd83ebd..827d9f360287 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7269,6 +7269,7 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 	struct ufs_dev_info *dev_info = &hba->dev_info;
 	u8 lun;
 	u32 d_lu_wb_buf_alloc;
+	u32 ext_ufs_feature;
 
 	if (!ufshcd_is_wb_allowed(hba))
 		return;
@@ -7286,11 +7287,10 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 	    DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP + 4)
 		goto wb_disabled;
 
-	dev_info->d_ext_ufs_feature_sup =
-		get_unaligned_be32(desc_buf +
-				   DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
+	ext_ufs_feature = get_unaligned_be32(desc_buf +
+					DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
 
-	if (!(dev_info->d_ext_ufs_feature_sup & UFS_DEV_WRITE_BOOSTER_SUP))
+	if (!(ext_ufs_feature & UFS_DEV_WRITE_BOOSTER_SUP))
 		goto wb_disabled;
 
 	/*
@@ -7305,10 +7305,8 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 		desc_buf[DEVICE_DESC_PARAM_WB_PRESRV_USRSPC_EN];
 
 	if (dev_info->b_wb_buffer_type == WB_BUF_MODE_SHARED) {
-		dev_info->d_wb_alloc_units =
-		get_unaligned_be32(desc_buf +
-				   DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS);
-		if (!dev_info->d_wb_alloc_units)
+		if (!get_unaligned_be32(desc_buf +
+				   DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS))
 			goto wb_disabled;
 	} else {
 		for (lun = 0; lun < UFS_UPIU_MAX_WB_LUN_ID; lun++) {
-- 
2.17.1

[PATCH v6 5/6] scsi: ufs: Group UFS WB related flags to struct ufs_dev_info

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

UFS device-related flags should be grouped in ufs_dev_info. Take
wb_enabled and wb_buf_flush_enabled out from the struct ufs_hba,
group them to struct ufs_dev_info, and align the names of the structure
members vertically.

Acked-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufs-sysfs.c |  2 +-
 drivers/scsi/ufs/ufs.h       | 27 ++++++++++++++++-----------
 drivers/scsi/ufs/ufshcd.c    | 21 ++++++++++-----------
 drivers/scsi/ufs/ufshcd.h    |  4 +---
 4 files changed, 28 insertions(+), 26 deletions(-)

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index 76db8593ca09..acc54f530f2d 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -214,7 +214,7 @@ static ssize_t wb_on_show(struct device *dev, struct device_attribute *attr,
 {
 	struct ufs_hba *hba = dev_get_drvdata(dev);
 
-	return sysfs_emit(buf, "%d\n", hba->wb_enabled);
+	return sysfs_emit(buf, "%d\n", hba->dev_info.wb_enabled);
 }
 
 static ssize_t wb_on_store(struct device *dev, struct device_attribute *attr,
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index a8000ed0017e..bf1897a72532 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -527,20 +527,25 @@ struct ufs_vreg_info {
 };
 
 struct ufs_dev_info {
-	bool f_power_on_wp_en;
+	bool	f_power_on_wp_en;
 	/* Keeps information if any of the LU is power on write protected */
-	bool is_lu_power_on_wp;
+	bool	is_lu_power_on_wp;
 	/* Maximum number of general LU supported by the UFS device */
-	u8 max_lu_supported;
-	u8 wb_dedicated_lu;
-	u16 wmanufacturerid;
+	u8	max_lu_supported;
+	u16	wmanufacturerid;
 	/*UFS device Product Name */
-	u8 *model;
-	u16 wspecversion;
-	u32 clk_gating_wait_us;
-	u8 b_wb_buffer_type;
-	bool b_rpm_dev_flush_capable;
-	u8 b_presrv_uspc_en;
+	u8	*model;
+	u16	wspecversion;
+	u32	clk_gating_wait_us;
+
+	/* UFS WB related flags */
+	bool    wb_enabled;
+	bool    wb_buf_flush_enabled;
+	u8	wb_dedicated_lu;
+	u8      wb_buffer_type;
+
+	bool	b_rpm_dev_flush_capable;
+	u8	b_presrv_uspc_en;
 };
 
 /*
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 827d9f360287..9f857af3766a 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -606,8 +606,8 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
 	if (!err) {
 		ufshcd_set_ufs_dev_active(hba);
 		if (ufshcd_is_wb_allowed(hba)) {
-			hba->wb_enabled = false;
-			hba->wb_buf_flush_enabled = false;
+			hba->dev_info.wb_enabled = false;
+			hba->dev_info.wb_buf_flush_enabled = false;
 		}
 	}
 	if (err != -EOPNOTSUPP)
@@ -5421,7 +5421,7 @@ int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable)
 	if (!ufshcd_is_wb_allowed(hba))
 		return 0;
 
-	if (!(enable ^ hba->wb_enabled))
+	if (!(enable ^ hba->dev_info.wb_enabled))
 		return 0;
 	if (enable)
 		opcode = UPIU_QUERY_OPCODE_SET_FLAG;
@@ -5437,7 +5437,7 @@ int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable)
 		return ret;
 	}
 
-	hba->wb_enabled = enable;
+	hba->dev_info.wb_enabled = enable;
 	dev_dbg(hba->dev, "%s write booster %s %d\n",
 			__func__, enable ? "enable" : "disable", ret);
 
@@ -5477,7 +5477,7 @@ static int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba)
 	int ret;
 	u8 index;
 
-	if (!ufshcd_is_wb_allowed(hba) || hba->wb_buf_flush_enabled)
+	if (!ufshcd_is_wb_allowed(hba) || hba->dev_info.wb_buf_flush_enabled)
 		return 0;
 
 	index = ufshcd_wb_get_query_index(hba);
@@ -5488,7 +5488,7 @@ static int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba)
 		dev_err(hba->dev, "%s WB - buf flush enable failed %d\n",
 			__func__, ret);
 	else
-		hba->wb_buf_flush_enabled = true;
+		hba->dev_info.wb_buf_flush_enabled = true;
 
 	dev_dbg(hba->dev, "WB - Flush enabled: %d\n", ret);
 	return ret;
@@ -5499,7 +5499,7 @@ static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba)
 	int ret;
 	u8 index;
 
-	if (!ufshcd_is_wb_allowed(hba) || !hba->wb_buf_flush_enabled)
+	if (!ufshcd_is_wb_allowed(hba) || !hba->dev_info.wb_buf_flush_enabled)
 		return 0;
 
 	index = ufshcd_wb_get_query_index(hba);
@@ -5510,7 +5510,7 @@ static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba)
 		dev_warn(hba->dev, "%s: WB - buf flush disable failed %d\n",
 			 __func__, ret);
 	} else {
-		hba->wb_buf_flush_enabled = false;
+		hba->dev_info.wb_buf_flush_enabled = false;
 		dev_dbg(hba->dev, "WB - Flush disabled: %d\n", ret);
 	}
 
@@ -7298,13 +7298,12 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 	 * says, in dedicated wb buffer mode, a max of 1 lun would have wb
 	 * buffer configured.
 	 */
-	dev_info->b_wb_buffer_type =
-		desc_buf[DEVICE_DESC_PARAM_WB_TYPE];
+	dev_info->wb_buffer_type = desc_buf[DEVICE_DESC_PARAM_WB_TYPE];
 
 	dev_info->b_presrv_uspc_en =
 		desc_buf[DEVICE_DESC_PARAM_WB_PRESRV_USRSPC_EN];
 
-	if (dev_info->b_wb_buffer_type == WB_BUF_MODE_SHARED) {
+	if (dev_info->wb_buffer_type == WB_BUF_MODE_SHARED) {
 		if (!get_unaligned_be32(desc_buf +
 				   DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS))
 			goto wb_disabled;
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index ac0f03f69e42..a599d6bb5c8c 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -818,8 +818,6 @@ struct ufs_hba {
 
 	struct device		bsg_dev;
 	struct request_queue	*bsg_queue;
-	bool wb_buf_flush_enabled;
-	bool wb_enabled;
 	struct delayed_work rpm_dev_flush_recheck_work;
 
 #ifdef CONFIG_SCSI_UFS_CRYPTO
@@ -967,7 +965,7 @@ static inline bool ufshcd_keep_autobkops_enabled_except_suspend(
 
 static inline u8 ufshcd_wb_get_query_index(struct ufs_hba *hba)
 {
-	if (hba->dev_info.b_wb_buffer_type == WB_BUF_MODE_LU_DEDICATED)
+	if (hba->dev_info.wb_buffer_type == WB_BUF_MODE_LU_DEDICATED)
 		return hba->dev_info.wb_dedicated_lu;
 	return 0;
 }
-- 
2.17.1

[PATCH v6 6/6] scsi: ufs: Cleanup WB buffer flush toggle implementation

[Bean Huo]

From: Bean Huo <beanhuo@micron.com>

Delete ufshcd_wb_buf_flush_enable() and ufshcd_wb_buf_flush_disable(),
move the implementation into ufshcd_wb_toggle_flush().

Signed-off-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufshcd.c | 66 +++++++++++++--------------------------
 1 file changed, 21 insertions(+), 45 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 9f857af3766a..10bee49ccbc8 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -247,10 +247,8 @@ static int ufshcd_setup_vreg(struct ufs_hba *hba, bool on);
 static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba,
 					 struct ufs_vreg *vreg);
 static int ufshcd_try_to_abort_task(struct ufs_hba *hba, int tag);
-static int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba);
-static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba);
 static int ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set);
-static inline void ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable);
+static inline int ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable);
 static void ufshcd_hba_vreg_set_lpm(struct ufs_hba *hba);
 static void ufshcd_hba_vreg_set_hpm(struct ufs_hba *hba);
 
@@ -5460,60 +5458,38 @@ static int ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set)
 				index, NULL);
 }
 
-static inline void ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable)
-{
-	if (hba->quirks & UFSHCI_QUIRK_SKIP_MANUAL_WB_FLUSH_CTRL)
-		return;
-
-	if (enable)
-		ufshcd_wb_buf_flush_enable(hba);
-	else
-		ufshcd_wb_buf_flush_disable(hba);
-
-}
-
-static int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba)
+static inline int ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable)
 {
 	int ret;
 	u8 index;
+	enum query_opcode opcode;
 
-	if (!ufshcd_is_wb_allowed(hba) || hba->dev_info.wb_buf_flush_enabled)
+	if (hba->quirks & UFSHCI_QUIRK_SKIP_MANUAL_WB_FLUSH_CTRL)
 		return 0;
 
-	index = ufshcd_wb_get_query_index(hba);
-	ret = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_SET_FLAG,
-				      QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN,
-				      index, NULL);
-	if (ret)
-		dev_err(hba->dev, "%s WB - buf flush enable failed %d\n",
-			__func__, ret);
-	else
-		hba->dev_info.wb_buf_flush_enabled = true;
-
-	dev_dbg(hba->dev, "WB - Flush enabled: %d\n", ret);
-	return ret;
-}
-
-static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba)
-{
-	int ret;
-	u8 index;
-
-	if (!ufshcd_is_wb_allowed(hba) || !hba->dev_info.wb_buf_flush_enabled)
+	if (!ufshcd_is_wb_allowed(hba) ||
+	    hba->dev_info.wb_buf_flush_enabled == enable)
 		return 0;
 
+	if (enable)
+		opcode = UPIU_QUERY_OPCODE_SET_FLAG;
+	else
+		opcode = UPIU_QUERY_OPCODE_CLEAR_FLAG;
+
 	index = ufshcd_wb_get_query_index(hba);
-	ret = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_CLEAR_FLAG,
-				      QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN,
-				      index, NULL);
+	ret = ufshcd_query_flag_retry(hba, opcode,
+				      QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN, index,
+				      NULL);
 	if (ret) {
-		dev_warn(hba->dev, "%s: WB - buf flush disable failed %d\n",
-			 __func__, ret);
-	} else {
-		hba->dev_info.wb_buf_flush_enabled = false;
-		dev_dbg(hba->dev, "WB - Flush disabled: %d\n", ret);
+		dev_err(hba->dev, "%s WB-Buf Flush %s failed %d\n", __func__,
+			enable ? "enable" : "disable", ret);
+		goto out;
 	}
 
+	hba->dev_info.wb_buf_flush_enabled = enable;
+
+	dev_dbg(hba->dev, "WB-Buf Flush %s\n", enable ? "enabled" : "disabled");
+out:
 	return ret;
 }
 
-- 
2.17.1

Re: [PATCH v6 1/6] scsi: ufs: Add "wb_on" sysfs node to control WB on/off

[Adrian Hunter]

On 18/01/21 10:10 pm, Bean Huo wrote:
> From: Bean Huo <beanhuo@micron.com>
> 
> Currently UFS WriteBooster driver uses clock scaling up/down to set
> WB on/off, for the platform which doesn't support UFSHCD_CAP_CLK_SCALING,
> WB will be always on. Provide a sysfs attribute to enable/disable WB
> during runtime. Write 1/0 to "wb_on" sysfs node to enable/disable UFS WB.

Is it so, that after a full reset, WB is always enabled again?  Is that
intended?

Re: [PATCH v6 1/6] scsi: ufs: Add "wb_on" sysfs node to control WB on/off

[Bean Huo]

On Tue, 2021-01-19 at 09:01 +0200, Adrian Hunter wrote:
> On 18/01/21 10:10 pm, Bean Huo wrote:
> > From: Bean Huo <beanhuo@micron.com>
> > 
> > Currently UFS WriteBooster driver uses clock scaling up/down to set
> > WB on/off, for the platform which doesn't support
> > UFSHCD_CAP_CLK_SCALING,
> > WB will be always on. Provide a sysfs attribute to enable/disable
> > WB
> > during runtime. Write 1/0 to "wb_on" sysfs node to enable/disable
> > UFS WB.
> 
> Is it so, that after a full reset, WB is always enabled again?  Is
> that
> intended?

Hello Adrian
Good questions. yes, after a full reset, the UFS device side by default
is wb disabled,  then WB will be always enabled agaion in
ufshcd_wb_config(hba). but, for the platform which
supports UFSHCD_CAP_CLK_SCALING, wb will be disabled again while clk
scaling down and enabled while clk scaling up.

Regarding the last question, I think OEM wants to do that. maybe they
suppose there will be a lot of writing after reset?? From the UFS
device's point of view, the control of WB is up to the user.

Thanks,
Bean

Re: [PATCH v6 1/6] scsi: ufs: Add "wb_on" sysfs node to control WB on/off

[Adrian Hunter]

On 19/01/21 11:33 am, Bean Huo wrote:
> On Tue, 2021-01-19 at 09:01 +0200, Adrian Hunter wrote:
>> On 18/01/21 10:10 pm, Bean Huo wrote:
>>> From: Bean Huo <beanhuo@micron.com>
>>>
>>> Currently UFS WriteBooster driver uses clock scaling up/down to set
>>> WB on/off, for the platform which doesn't support
>>> UFSHCD_CAP_CLK_SCALING,
>>> WB will be always on. Provide a sysfs attribute to enable/disable
>>> WB
>>> during runtime. Write 1/0 to "wb_on" sysfs node to enable/disable
>>> UFS WB.
>>
>> Is it so, that after a full reset, WB is always enabled again?  Is
>> that
>> intended?
> 
> Hello Adrian
> Good questions. yes, after a full reset, the UFS device side by default
> is wb disabled,  then WB will be always enabled agaion in
> ufshcd_wb_config(hba). but, for the platform which
> supports UFSHCD_CAP_CLK_SCALING, wb will be disabled again while clk
> scaling down and enabled while clk scaling up.
> 
> Regarding the last question, I think OEM wants to do that. maybe they
> suppose there will be a lot of writing after reset?? From the UFS
> device's point of view, the control of WB is up to the user.

If it is by design enabled after reset, then perhaps it should be mentioned
in the sysfs documentation.

Re: [PATCH v6 1/6] scsi: ufs: Add "wb_on" sysfs node to control WB on/off

[Bean Huo]

On Tue, 2021-01-19 at 12:00 +0200, Adrian Hunter wrote:
> > > Is it so, that after a full reset, WB is always enabled again? 
> > > Is
> > > that
> > > intended?
> > 
> > Hello Adrian
> > Good questions. yes, after a full reset, the UFS device side by
> > default
> > is wb disabled,  then WB will be always enabled agaion in
> > ufshcd_wb_config(hba). but, for the platform which
> > supports UFSHCD_CAP_CLK_SCALING, wb will be disabled again while
> > clk
> > scaling down and enabled while clk scaling up.
> > 
> > Regarding the last question, I think OEM wants to do that. maybe
> > they
> > suppose there will be a lot of writing after reset?? From the UFS
> > device's point of view, the control of WB is up to the user.
> 
> If it is by design enabled after reset, then perhaps it should be
> mentioned
> in the sysfs documentation.

ok, will add it in the next version.

thanks,
Bean