[<RFC RESEND PATCH v2> 0/3] WriteBooster Feature Support

[<RFC RESEND PATCH v2> 0/3] WriteBooster Feature Support

[Asutosh Das]

Still a RFC patch, because I'm still expecting some comments
on the design.

v1 -> v2:
- Addressed comments on v1

- Supports shared buffer mode only

- Didn't use exception event as suggested.
  The reason being while testing I saw that the WriteBooster
  available buffer remains at 0x1 for a longer time if flush is
  enabled all the time as compared to an event-based enablement.
  This essentially means that writes go to the WriteBooster buffer
  more. Spec says that the if flush is enabled, the device would
  flush when it sees the command queue empty. So I guess that'd trigger
  flush more than an event based approach.
  Anyway the Vcc would be turned-off during system suspend, so flush
  would stop anyway.
  In this patchset, I never turn-off flush.
  Hence the RFC.

Asutosh Das (3):
  scsi: ufs: add write booster feature support
  ufs-qcom: scsi: configure write booster type
  ufs: sysfs: add sysfs entries for write booster

 drivers/scsi/ufs/ufs-qcom.c  |   7 ++
 drivers/scsi/ufs/ufs-sysfs.c |  39 ++++++-
 drivers/scsi/ufs/ufs.h       |  37 ++++++-
 drivers/scsi/ufs/ufshcd.c    | 238 ++++++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/ufs/ufshcd.h    |   9 ++
 5 files changed, 324 insertions(+), 6 deletions(-)

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.

[<RFC RESEND PATCH v2> 1/3] scsi: ufs: add write booster feature support

[Asutosh Das]

The write performance of TLC NAND is considerably
lower than SLC NAND. Using SLC NAND as a WriteBooster
Buffer enables the write request to be processed with
lower latency and improves the overall write performance.

Adds support for shared-buffer mode WriteBooster.

WriteBooster enable: SW enables it when clocks are
scaled up, thus it's enabled only in high load conditions.

WriteBooster disable: SW will disable the feature,
when clocks are scaled down. Thus writes would go as normal
writes.

To keep the endurance of the WriteBooster Buffer at a
maximum, this load based toggling is adopted.

Change-Id: I89c488a7641697173a296c1ebadc1f4720090cfd
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
---
 drivers/scsi/ufs/ufs.h    |  31 +++++-
 drivers/scsi/ufs/ufshcd.c | 238 +++++++++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/ufs/ufshcd.h |   9 ++
 3 files changed, 273 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 990cb48..2c77b3e 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -140,6 +140,9 @@ enum flag_idn {
 	QUERY_FLAG_IDN_BUSY_RTC				= 0x09,
 	QUERY_FLAG_IDN_RESERVED3			= 0x0A,
 	QUERY_FLAG_IDN_PERMANENTLY_DISABLE_FW_UPDATE	= 0x0B,
+	QUERY_FLAG_IDN_WB_EN                            = 0x0E,
+	QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN                 = 0x0F,
+	QUERY_FLAG_IDN_WB_BUFF_FLUSH_DURING_HIBERN8     = 0x10,
 };
 
 /* Attribute idn for Query requests */
@@ -168,6 +171,10 @@ enum attr_idn {
 	QUERY_ATTR_IDN_PSA_STATE		= 0x15,
 	QUERY_ATTR_IDN_PSA_DATA_SIZE		= 0x16,
 	QUERY_ATTR_IDN_REF_CLK_GATING_WAIT_TIME	= 0x17,
+	QUERY_ATTR_IDN_WB_FLUSH_STATUS	        = 0x1C,
+	QUERY_ATTR_IDN_AVAIL_WB_BUFF_SIZE       = 0x1D,
+	QUERY_ATTR_IDN_WB_BUFF_LIFE_TIME_EST    = 0x1E,
+	QUERY_ATTR_IDN_CURR_WB_BUFF_SIZE        = 0x1F,
 };
 
 /* Descriptor idn for Query requests */
@@ -191,7 +198,7 @@ enum desc_header_offset {
 };
 
 enum ufs_desc_def_size {
-	QUERY_DESC_DEVICE_DEF_SIZE		= 0x40,
+	QUERY_DESC_DEVICE_DEF_SIZE		= 0x59,
 	QUERY_DESC_CONFIGURATION_DEF_SIZE	= 0x90,
 	QUERY_DESC_UNIT_DEF_SIZE		= 0x23,
 	QUERY_DESC_INTERCONNECT_DEF_SIZE	= 0x06,
@@ -219,6 +226,7 @@ enum unit_desc_param {
 	UNIT_DESC_PARAM_PHY_MEM_RSRC_CNT	= 0x18,
 	UNIT_DESC_PARAM_CTX_CAPABILITIES	= 0x20,
 	UNIT_DESC_PARAM_LARGE_UNIT_SIZE_M1	= 0x22,
+	UNIT_DESC_PARAM_WB_BUF_ALLOC_UNITS	= 0x29,
 };
 
 /* Device descriptor parameters offsets in bytes*/
@@ -258,6 +266,9 @@ enum device_desc_param {
 	DEVICE_DESC_PARAM_PSA_MAX_DATA		= 0x25,
 	DEVICE_DESC_PARAM_PSA_TMT		= 0x29,
 	DEVICE_DESC_PARAM_PRDCT_REV		= 0x2A,
+	DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP	= 0x4F,
+	DEVICE_DESC_PARAM_WB_TYPE		= 0x54,
+	DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS = 0x55,
 };
 
 /* Interconnect descriptor parameters offsets in bytes*/
@@ -333,6 +344,11 @@ enum {
 	UFSHCD_AMP		= 3,
 };
 
+/* Possible values for dExtendedUFSFeaturesSupport */
+enum {
+	UFS_DEV_WRITE_BOOSTER_SUP	= BIT(8),
+};
+
 #define POWER_DESC_MAX_SIZE			0x62
 #define POWER_DESC_MAX_ACTV_ICC_LVLS		16
 
@@ -447,6 +463,15 @@ enum ufs_dev_pwr_mode {
 	UFS_POWERDOWN_PWR_MODE	= 3,
 };
 
+enum ufs_dev_wb_buf_avail_size {
+	UFS_WB_10_PERCENT_BUF_REMAIN = 0x1,
+	UFS_WB_40_PERCENT_BUF_REMAIN = 0x4,
+};
+
+enum ufs_dev_wb_buf_user_cap_config {
+	UFS_WB_BUFF_PRESERVE_USER_SPACE = 1,
+	UFS_WB_BUFF_USER_SPACE_RED_EN = 2,
+};
 /**
  * struct utp_cmd_rsp - Response UPIU structure
  * @residual_transfer_count: Residual transfer count DW-3
@@ -537,6 +562,10 @@ 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 keep_vcc_on;
 };
 
 /**
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 2a2a63b..a78dcb6 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -47,6 +47,8 @@
 #include "unipro.h"
 #include "ufs-sysfs.h"
 #include "ufs_bsg.h"
+#include <linux/blkdev.h>
+#include <asm/unaligned.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/ufs.h>
@@ -263,6 +265,13 @@ static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up);
 static irqreturn_t ufshcd_intr(int irq, void *__hba);
 static int ufshcd_change_power_mode(struct ufs_hba *hba,
 			     struct ufs_pa_layer_attr *pwr_mode);
+static bool ufshcd_wb_sup(struct ufs_hba *hba);
+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 inline bool ufshcd_valid_tag(struct ufs_hba *hba, int tag)
 {
 	return tag >= 0 && tag < hba->nutrs;
@@ -284,6 +293,25 @@ static inline void ufshcd_disable_irq(struct ufs_hba *hba)
 	}
 }
 
+static inline void ufshcd_wb_config(struct ufs_hba *hba)
+{
+	int ret;
+
+	if (!ufshcd_wb_sup(hba))
+		return;
+
+	ret = ufshcd_wb_ctrl(hba, true);
+	if (ret)
+		dev_err(hba->dev, "%s: Enable WB failed: %d\n", __func__, ret);
+	else
+		dev_info(hba->dev, "%s: Write Booster Configured\n", __func__);
+	ret = ufshcd_wb_toggle_flush_during_h8(hba, true);
+	if (ret)
+		dev_err(hba->dev, "%s: En WB flush during H8: failed: %d\n",
+			__func__, ret);
+	ufshcd_wb_toggle_flush(hba, true);
+}
+
 static void ufshcd_scsi_unblock_requests(struct ufs_hba *hba)
 {
 	if (atomic_dec_and_test(&hba->scsi_block_reqs_cnt))
@@ -1132,6 +1160,10 @@ static int ufshcd_devfreq_scale(struct ufs_hba *hba, bool scale_up)
 	}
 
 	ret = ufshcd_vops_clk_scale_notify(hba, scale_up, POST_CHANGE);
+	/* Enable Write Booster if we have scaled up else disable it */
+	up_write(&hba->clk_scaling_lock);
+	ufshcd_wb_ctrl(hba, scale_up);
+	down_write(&hba->clk_scaling_lock);
 
 out:
 	ufshcd_clock_scaling_unprepare(hba);
@@ -5105,6 +5137,167 @@ static void ufshcd_bkops_exception_event_handler(struct ufs_hba *hba)
 				__func__, err);
 }
 
+static bool ufshcd_wb_sup(struct ufs_hba *hba)
+{
+	return ((hba->dev_info.d_ext_ufs_feature_sup &
+		 UFS_DEV_WRITE_BOOSTER_SUP) &&
+		hba->dev_info.b_wb_buffer_type &&
+		hba->dev_info.d_wb_alloc_units);
+}
+
+static int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable)
+{
+	int ret;
+	enum query_opcode opcode;
+
+	if (!ufshcd_wb_sup(hba))
+		return 0;
+
+	if (!(enable ^ hba->wb_enabled))
+		return 0;
+	if (enable)
+		opcode = UPIU_QUERY_OPCODE_SET_FLAG;
+	else
+		opcode = UPIU_QUERY_OPCODE_CLEAR_FLAG;
+
+	ret = ufshcd_query_flag_retry(hba, opcode,
+				      QUERY_FLAG_IDN_WB_EN, NULL);
+	if (ret) {
+		dev_err(hba->dev, "%s write booster %s failed %d\n",
+			__func__, enable ? "enable" : "disable", ret);
+		return ret;
+	}
+
+	hba->wb_enabled = enable;
+	dev_dbg(hba->dev, "%s write booster %s %d\n",
+			__func__, enable ? "enable" : "disable", ret);
+
+	return ret;
+}
+
+static int ufshcd_wb_toggle_flush_during_h8(struct ufs_hba *hba, bool set)
+{
+	int val;
+
+	if (set)
+		val =  UPIU_QUERY_OPCODE_SET_FLAG;
+	else
+		val = UPIU_QUERY_OPCODE_CLEAR_FLAG;
+
+	return ufshcd_query_flag_retry(hba, val,
+			       QUERY_FLAG_IDN_WB_BUFF_FLUSH_DURING_HIBERN8,
+				       NULL);
+}
+
+static inline void ufshcd_wb_toggle_flush(struct ufs_hba *hba, bool enable)
+{
+	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)
+{
+	int ret;
+
+	if (!ufshcd_wb_sup(hba) || hba->wb_buf_flush_enabled)
+		return 0;
+
+	ret = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_SET_FLAG,
+				      QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN, NULL);
+	if (ret)
+		dev_err(hba->dev, "%s WB - buf flush enable failed %d\n",
+			__func__, ret);
+	else
+		hba->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;
+
+	if (!ufshcd_wb_sup(hba) || !hba->wb_buf_flush_enabled)
+		return 0;
+
+	ret = ufshcd_query_flag_retry(hba, UPIU_QUERY_OPCODE_CLEAR_FLAG,
+				      QUERY_FLAG_IDN_WB_BUFF_FLUSH_EN, NULL);
+	if (ret) {
+		dev_warn(hba->dev, "%s: WB - buf flush disable failed %d\n",
+			 __func__, ret);
+	} else {
+		hba->wb_buf_flush_enabled = false;
+		dev_dbg(hba->dev, "WB - Flush disabled: %d\n", ret);
+	}
+
+	return ret;
+}
+
+static bool ufshcd_wb_keep_vcc_on(struct ufs_hba *hba)
+{
+	int ret;
+	u32 cur_buf, avail_buf;
+
+	if (!ufshcd_wb_sup(hba))
+		return false;
+	/*
+	 * The ufs device needs the vcc to be ON to flush.
+	 * With user-space reduction enabled, it's enough to enable flush
+	 * by checking only the available buffer. The threshold
+	 * defined here is > 90% full.
+	 * With user-space preserved enabled, the current-buffer
+	 * should be checked too because the wb buffer size can reduce
+	 * when disk tends to be full. This info is provided by current
+	 * buffer (dCurrentWriteBoosterBufferSize). There's no point in
+	 * keeping vcc on when current buffer is empty.
+	 */
+	ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+				      QUERY_ATTR_IDN_AVAIL_WB_BUFF_SIZE,
+				      0, 0, &avail_buf);
+	if (ret) {
+		dev_warn(hba->dev, "%s dAvailableWriteBoosterBufferSize read failed %d\n",
+			 __func__, ret);
+		return false;
+	}
+
+	ret = ufshcd_vops_get_user_cap_mode(hba);
+	if (ret <= 0) {
+		dev_dbg(hba->dev, "Get user-cap reduction mode: failed: %d\n",
+			ret);
+		/* Most commonly used */
+		ret = UFS_WB_BUFF_PRESERVE_USER_SPACE;
+	}
+
+	if (ret == UFS_WB_BUFF_USER_SPACE_RED_EN) {
+		if (avail_buf <= UFS_WB_10_PERCENT_BUF_REMAIN)
+			return true;
+		return false;
+	} else if (ret == UFS_WB_BUFF_PRESERVE_USER_SPACE) {
+		ret = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+					      QUERY_ATTR_IDN_CURR_WB_BUFF_SIZE,
+					      0, 0, &cur_buf);
+		if (ret) {
+			dev_err(hba->dev, "%s dCurWriteBoosterBufferSize read failed %d\n",
+				 __func__, ret);
+			return false;
+		}
+
+		if (!cur_buf) {
+			dev_info(hba->dev, "dCurWBBuf: %d WB disabled until free-space is available\n",
+				 cur_buf);
+			return false;
+		}
+		/* Let it continue to flush when >60% full */
+		if (avail_buf < UFS_WB_40_PERCENT_BUF_REMAIN)
+			return true;
+	}
+	return false;
+}
+
 /**
  * ufshcd_exception_event_handler - handle exceptions raised by device
  * @work: pointer to work data
@@ -6571,6 +6764,28 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 				      desc_buf[DEVICE_DESC_PARAM_SPEC_VER + 1];
 
 	model_index = desc_buf[DEVICE_DESC_PARAM_PRDCT_NAME];
+	/* Enable WB only for UFS-3.1 */
+	if (dev_info->wspecversion >= 0x310) {
+		hba->dev_info.d_ext_ufs_feature_sup =
+			get_unaligned_be32(desc_buf +
+				DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
+		/*
+		 * 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.
+		 */
+		hba->dev_info.b_wb_buffer_type =
+			desc_buf[DEVICE_DESC_PARAM_WB_TYPE];
+
+		if (!hba->dev_info.b_wb_buffer_type)
+			goto skip_alloc_unit;
+		hba->dev_info.d_wb_alloc_units =
+			get_unaligned_be32(desc_buf +
+				DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS);
+	}
+
+skip_alloc_unit:
 	err = ufshcd_read_string_desc(hba, model_index,
 				      &dev_info->model, SD_ASCII_STD);
 	if (err < 0) {
@@ -7074,6 +7289,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async)
 	/* set the state as operational after switching to desired gear */
 	hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
 
+	ufshcd_wb_config(hba);
 	/* Enable Auto-Hibernate if configured */
 	ufshcd_auto_hibern8_enable(hba);
 
@@ -7734,12 +7950,16 @@ static void ufshcd_vreg_set_lpm(struct ufs_hba *hba)
 	 *
 	 * Ignore the error returned by ufshcd_toggle_vreg() as device is anyway
 	 * in low power state which would save some power.
+	 *
+	 * If Write Booster is enabled and the device needs to flush the WB
+	 * buffer OR if bkops status is urgent for WB, keep Vcc on.
 	 */
 	if (ufshcd_is_ufs_dev_poweroff(hba) && ufshcd_is_link_off(hba) &&
 	    !hba->dev_info.is_lu_power_on_wp) {
 		ufshcd_setup_vreg(hba, false);
 	} else if (!ufshcd_is_ufs_dev_active(hba)) {
-		ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
+		if (!hba->dev_info.keep_vcc_on)
+			ufshcd_toggle_vreg(hba->dev, hba->vreg_info.vcc, false);
 		if (!ufshcd_is_link_active(hba)) {
 			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq);
 			ufshcd_config_vreg_lpm(hba, hba->vreg_info.vccq2);
@@ -7863,12 +8083,22 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 			/* make sure that auto bkops is disabled */
 			ufshcd_disable_auto_bkops(hba);
 		}
+		/*
+		 * With wb enabled, if the bkops is enabled or if the
+		 * configured WB type is 70% full, keep vcc ON
+		 * for the device to flush the wb buffer
+		 */
+		if ((hba->auto_bkops_enabled && ufshcd_wb_sup(hba)) ||
+		    ufshcd_wb_keep_vcc_on(hba))
+			hba->dev_info.keep_vcc_on = true;
+	} else if (!ufshcd_is_runtime_pm(pm_op)) {
+		hba->dev_info.keep_vcc_on = false;
 	}
 
 	if ((req_dev_pwr_mode != hba->curr_dev_pwr_mode) &&
-	     ((ufshcd_is_runtime_pm(pm_op) && !hba->auto_bkops_enabled) ||
-	       !ufshcd_is_runtime_pm(pm_op))) {
-		/* ensure that bkops is disabled */
+	    ((ufshcd_is_runtime_pm(pm_op) && !hba->auto_bkops_enabled) ||
+	     !ufshcd_is_runtime_pm(pm_op))) {
+		/* ensure that bkops & wb-flush is disabled */
 		ufshcd_disable_auto_bkops(hba);
 		ret = ufshcd_set_dev_pwr_mode(hba, req_dev_pwr_mode);
 		if (ret)
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index d45a044..c343781 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -327,6 +327,7 @@ struct ufs_hba_variant_ops {
 	void	(*dbg_register_dump)(struct ufs_hba *hba);
 	int	(*phy_initialization)(struct ufs_hba *);
 	void	(*device_reset)(struct ufs_hba *hba);
+	u32	(*wb_get_user_cap_mode)(struct ufs_hba *hba);
 };
 
 /* clock gating state  */
@@ -711,6 +712,8 @@ struct ufs_hba {
 
 	struct device		bsg_dev;
 	struct request_queue	*bsg_queue;
+	bool wb_buf_flush_enabled;
+	bool wb_enabled;
 };
 
 /* Returns true if clocks can be gated. Otherwise false */
@@ -1103,4 +1106,10 @@ static inline u8 ufshcd_scsi_to_upiu_lun(unsigned int scsi_lun)
 int ufshcd_dump_regs(struct ufs_hba *hba, size_t offset, size_t len,
 		     const char *prefix);
 
+static inline unsigned int ufshcd_vops_get_user_cap_mode(struct ufs_hba *hba)
+{
+	if (hba->vops && hba->vops->wb_get_user_cap_mode)
+		return hba->vops->wb_get_user_cap_mode(hba);
+	return 0;
+}
 #endif /* End of Header */
-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.

[<RFC RESEND PATCH v2> 2/3] ufs-qcom: scsi: configure write booster type

[Asutosh Das]

Configure the WriteBooster type to preserve user-space mode.
This would ensure that no user-space capacity is reduced
when write booster is enabled.

Change-Id: I4144531a73ea3b5d5ede76beae45722366b1e75c
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
---
 drivers/scsi/ufs/ufs-qcom.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index 6115ac6..59f3243 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -1689,6 +1689,12 @@ static void ufs_qcom_device_reset(struct ufs_hba *hba)
 	usleep_range(10, 15);
 }
 
+static u32 ufs_qcom_wb_get_user_cap_mode(struct ufs_hba *hba)
+{
+	/* QCom prefers no user-space reduction mode */
+	return UFS_WB_BUFF_PRESERVE_USER_SPACE;
+}
+
 /**
  * struct ufs_hba_qcom_vops - UFS QCOM specific variant operations
  *
@@ -1710,6 +1716,7 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = {
 	.resume			= ufs_qcom_resume,
 	.dbg_register_dump	= ufs_qcom_dump_dbg_regs,
 	.device_reset		= ufs_qcom_device_reset,
+	.wb_get_user_cap_mode	= ufs_qcom_wb_get_user_cap_mode,
 };
 
 /**
-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.

[<RFC RESEND PATCH v2> 3/3] ufs: sysfs: add sysfs entries for write booster

[Asutosh Das]

Adds unit, device, geometry descriptor sysfs entries.
Adds flags sysfs entries for write booster.

Change-Id: I53ac9e83baa4a012187ee215280032d96deedf62
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
---
 drivers/scsi/ufs/ufs-sysfs.c | 39 ++++++++++++++++++++++++++++++++++++++-
 drivers/scsi/ufs/ufs.h       |  6 ++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c
index dbdf8b0..db3b932 100644
--- a/drivers/scsi/ufs/ufs-sysfs.c
+++ b/drivers/scsi/ufs/ufs-sysfs.c
@@ -274,6 +274,10 @@ UFS_DEVICE_DESC_PARAM(device_version, _DEV_VER, 2);
 UFS_DEVICE_DESC_PARAM(number_of_secure_wpa, _NUM_SEC_WPA, 1);
 UFS_DEVICE_DESC_PARAM(psa_max_data_size, _PSA_MAX_DATA, 4);
 UFS_DEVICE_DESC_PARAM(psa_state_timeout, _PSA_TMT, 1);
+UFS_DEVICE_DESC_PARAM(ext_feature_sup, _EXT_UFS_FEATURE_SUP, 4);
+UFS_DEVICE_DESC_PARAM(wb_presv_us_en, _WB_US_RED_EN, 1);
+UFS_DEVICE_DESC_PARAM(wb_type, _WB_TYPE, 1);
+UFS_DEVICE_DESC_PARAM(wb_shared_alloc_units, _WB_SHARED_ALLOC_UNITS, 4);
 
 static struct attribute *ufs_sysfs_device_descriptor[] = {
 	&dev_attr_device_type.attr,
@@ -302,6 +306,10 @@ static struct attribute *ufs_sysfs_device_descriptor[] = {
 	&dev_attr_number_of_secure_wpa.attr,
 	&dev_attr_psa_max_data_size.attr,
 	&dev_attr_psa_state_timeout.attr,
+	&dev_attr_ext_feature_sup.attr,
+	&dev_attr_wb_presv_us_en.attr,
+	&dev_attr_wb_type.attr,
+	&dev_attr_wb_shared_alloc_units.attr,
 	NULL,
 };
 
@@ -371,6 +379,12 @@ UFS_GEOMETRY_DESC_PARAM(enh4_memory_max_alloc_units,
 	_ENM4_MAX_NUM_UNITS, 4);
 UFS_GEOMETRY_DESC_PARAM(enh4_memory_capacity_adjustment_factor,
 	_ENM4_CAP_ADJ_FCTR, 2);
+UFS_GEOMETRY_DESC_PARAM(wb_max_alloc_units, _WB_MAX_ALLOC_UNITS, 4);
+UFS_GEOMETRY_DESC_PARAM(wb_max_wb_luns, _WB_MAX_WB_LUNS, 1);
+UFS_GEOMETRY_DESC_PARAM(wb_buff_cap_adj, _WB_BUFF_CAP_ADJ, 1);
+UFS_GEOMETRY_DESC_PARAM(wb_sup_red_type, _WB_SUP_RED_TYPE, 1);
+UFS_GEOMETRY_DESC_PARAM(wb_sup_wb_type, _WB_SUP_WB_TYPE, 1);
+
 
 static struct attribute *ufs_sysfs_geometry_descriptor[] = {
 	&dev_attr_raw_device_capacity.attr,
@@ -402,6 +416,11 @@ static struct attribute *ufs_sysfs_geometry_descriptor[] = {
 	&dev_attr_enh3_memory_capacity_adjustment_factor.attr,
 	&dev_attr_enh4_memory_max_alloc_units.attr,
 	&dev_attr_enh4_memory_capacity_adjustment_factor.attr,
+	&dev_attr_wb_max_alloc_units.attr,
+	&dev_attr_wb_max_wb_luns.attr,
+	&dev_attr_wb_buff_cap_adj.attr,
+	&dev_attr_wb_sup_red_type.attr,
+	&dev_attr_wb_sup_wb_type.attr,
 	NULL,
 };
 
@@ -608,7 +627,7 @@ static ssize_t _name##_show(struct device *dev,				\
 	if (ufshcd_query_flag(hba, UPIU_QUERY_OPCODE_READ_FLAG,		\
 		QUERY_FLAG_IDN##_uname, &flag))				\
 		return -EINVAL;						\
-	return sprintf(buf, "%s\n", flag ? "true" : "false");		\
+	return sprintf(buf, "%s\n", flag ? "true" : "false"); \
 }									\
 static DEVICE_ATTR_RO(_name)
 
@@ -620,6 +639,9 @@ UFS_FLAG(life_span_mode_enable, _LIFE_SPAN_MODE_ENABLE);
 UFS_FLAG(phy_resource_removal, _FPHYRESOURCEREMOVAL);
 UFS_FLAG(busy_rtc, _BUSY_RTC);
 UFS_FLAG(disable_fw_update, _PERMANENTLY_DISABLE_FW_UPDATE);
+UFS_FLAG(wb_enable, _WB_EN);
+UFS_FLAG(wb_flush_en, _WB_BUFF_FLUSH_EN);
+UFS_FLAG(wb_flush_during_h8, _WB_BUFF_FLUSH_DURING_HIBERN8);
 
 static struct attribute *ufs_sysfs_device_flags[] = {
 	&dev_attr_device_init.attr,
@@ -630,6 +652,9 @@ static struct attribute *ufs_sysfs_device_flags[] = {
 	&dev_attr_phy_resource_removal.attr,
 	&dev_attr_busy_rtc.attr,
 	&dev_attr_disable_fw_update.attr,
+	&dev_attr_wb_enable.attr,
+	&dev_attr_wb_flush_en.attr,
+	&dev_attr_wb_flush_during_h8.attr,
 	NULL,
 };
 
@@ -667,6 +692,11 @@ UFS_ATTRIBUTE(exception_event_status, _EE_STATUS);
 UFS_ATTRIBUTE(ffu_status, _FFU_STATUS);
 UFS_ATTRIBUTE(psa_state, _PSA_STATE);
 UFS_ATTRIBUTE(psa_data_size, _PSA_DATA_SIZE);
+UFS_ATTRIBUTE(wb_flush_status, _WB_FLUSH_STATUS);
+UFS_ATTRIBUTE(wb_avail_buf, _AVAIL_WB_BUFF_SIZE);
+UFS_ATTRIBUTE(wb_life_time_est, _WB_BUFF_LIFE_TIME_EST);
+UFS_ATTRIBUTE(wb_cur_buf, _CURR_WB_BUFF_SIZE);
+
 
 static struct attribute *ufs_sysfs_attributes[] = {
 	&dev_attr_boot_lun_enabled.attr,
@@ -685,6 +715,10 @@ static struct attribute *ufs_sysfs_attributes[] = {
 	&dev_attr_ffu_status.attr,
 	&dev_attr_psa_state.attr,
 	&dev_attr_psa_data_size.attr,
+	&dev_attr_wb_flush_status.attr,
+	&dev_attr_wb_avail_buf.attr,
+	&dev_attr_wb_life_time_est.attr,
+	&dev_attr_wb_cur_buf.attr,
 	NULL,
 };
 
@@ -736,6 +770,8 @@ UFS_UNIT_DESC_PARAM(provisioning_type, _PROVISIONING_TYPE, 1);
 UFS_UNIT_DESC_PARAM(physical_memory_resourse_count, _PHY_MEM_RSRC_CNT, 8);
 UFS_UNIT_DESC_PARAM(context_capabilities, _CTX_CAPABILITIES, 2);
 UFS_UNIT_DESC_PARAM(large_unit_granularity, _LARGE_UNIT_SIZE_M1, 1);
+UFS_UNIT_DESC_PARAM(wb_buf_alloc_units, _WB_BUF_ALLOC_UNITS, 4);
+
 
 static struct attribute *ufs_sysfs_unit_descriptor[] = {
 	&dev_attr_boot_lun_id.attr,
@@ -751,6 +787,7 @@ static struct attribute *ufs_sysfs_unit_descriptor[] = {
 	&dev_attr_physical_memory_resourse_count.attr,
 	&dev_attr_context_capabilities.attr,
 	&dev_attr_large_unit_granularity.attr,
+	&dev_attr_wb_buf_alloc_units.attr,
 	NULL,
 };
 
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 2c77b3e..5c26659 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -267,6 +267,7 @@ enum device_desc_param {
 	DEVICE_DESC_PARAM_PSA_TMT		= 0x29,
 	DEVICE_DESC_PARAM_PRDCT_REV		= 0x2A,
 	DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP	= 0x4F,
+	DEVICE_DESC_PARAM_WB_US_RED_EN		= 0x53,
 	DEVICE_DESC_PARAM_WB_TYPE		= 0x54,
 	DEVICE_DESC_PARAM_WB_SHARED_ALLOC_UNITS = 0x55,
 };
@@ -313,6 +314,11 @@ enum geometry_desc_param {
 	GEOMETRY_DESC_PARAM_ENM4_MAX_NUM_UNITS	= 0x3E,
 	GEOMETRY_DESC_PARAM_ENM4_CAP_ADJ_FCTR	= 0x42,
 	GEOMETRY_DESC_PARAM_OPT_LOG_BLK_SIZE	= 0x44,
+	GEOMETRY_DESC_PARAM_WB_MAX_ALLOC_UNITS	= 0x4F,
+	GEOMETRY_DESC_PARAM_WB_MAX_WB_LUNS	= 0x53,
+	GEOMETRY_DESC_PARAM_WB_BUFF_CAP_ADJ	= 0x54,
+	GEOMETRY_DESC_PARAM_WB_SUP_RED_TYPE	= 0x55,
+	GEOMETRY_DESC_PARAM_WB_SUP_WB_TYPE	= 0x56,
 };
 
 /* Health descriptor parameters offsets in bytes*/
-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.

RE: [<RFC RESEND PATCH v2> 0/3] WriteBooster Feature Support

[Avri Altman]

Hi,
The code looks good to me and I encourage you to submit your patches.
I just want to make some general remarks:
 - The way you use the clock scaling to set WB on/off, is IMO, an elegant design choice.
 - You should add a platform capability for WB
 - As for setting user space configuration options - I think you've got it wrong.
   You should read it from  bSupportedWriteBoosterBufferUserSpaceReductionTypes
   (offset 0x55 in the device descriptor).
   This is a configurable parameter that the chipset vendor control and can set during provisioning.
 - I agree with your approach toward flush during runtime suspend (keep-vcc-on):
    it is the host's interest to assist the device with some extra idle time if needed for WB flush.
    This way you will assure consistent write performance.

Thanks,
Avri

> 
> 
> Still a RFC patch, because I'm still expecting some comments
> on the design.
> 
> v1 -> v2:
> - Addressed comments on v1
> 
> - Supports shared buffer mode only
> 
> - Didn't use exception event as suggested.
>   The reason being while testing I saw that the WriteBooster
>   available buffer remains at 0x1 for a longer time if flush is
>   enabled all the time as compared to an event-based enablement.
>   This essentially means that writes go to the WriteBooster buffer
>   more. Spec says that the if flush is enabled, the device would
>   flush when it sees the command queue empty. So I guess that'd trigger
>   flush more than an event based approach.
>   Anyway the Vcc would be turned-off during system suspend, so flush
>   would stop anyway.
>   In this patchset, I never turn-off flush.
>   Hence the RFC.
> 
> Asutosh Das (3):
>   scsi: ufs: add write booster feature support
>   ufs-qcom: scsi: configure write booster type
>   ufs: sysfs: add sysfs entries for write booster
> 
>  drivers/scsi/ufs/ufs-qcom.c  |   7 ++
>  drivers/scsi/ufs/ufs-sysfs.c |  39 ++++++-
>  drivers/scsi/ufs/ufs.h       |  37 ++++++-
>  drivers/scsi/ufs/ufshcd.c    | 238
> ++++++++++++++++++++++++++++++++++++++++++-
>  drivers/scsi/ufs/ufshcd.h    |   9 ++
>  5 files changed, 324 insertions(+), 6 deletions(-)
> 
> --
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a
> Linux Foundation Collaborative Project.