From e3d55626cff32cf7defff7f2053672adc4a712da Mon Sep 17 00:00:00 2001 From: Lu Hongfei Date: Tue, 13 Jun 2023 10:22:34 +0800 Subject: [PATCH] scsi: ufs: wb: Add explicit flush_threshold sysfs attribute There are three flags that control Write Booster Feature: 1. WB ON/OFF 2. WB Hibern Flush ON/OFF (implicitly) 3. WB Flush ON/OFF (explicit) In the case of "Hibern Flush", one of the conditions for flush WB buffer is that avail_wb_buff < wb_flush_threshold. As we know, different users have different requirements for power consumption and performance. Therefore, we need the ability to manually set wb_flush_threshold, so that users can easily and flexibly adjust the wb_flush_threshold value, thereby achieving a balance between power consumption and performance. So the sysfs attribute that controls this is necessary. wb_flush_threshold represents the threshold for flushing WB buffer, whose value expressed in unit of 10% granularity, such as '1' representing 10%, '2' representing 20%, and so on. Signed-off-by: Lu Hongfei Link: https://lore.kernel.org/r/20230613022240.16595-1-luhongfei@vivo.com Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- Documentation/ABI/testing/sysfs-driver-ufs | 11 ++++++++++ drivers/ufs/core/ufs-sysfs.c | 33 ++++++++++++++++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-driver-ufs b/Documentation/ABI/testing/sysfs-driver-ufs index 228aa43..d5f44fc 100644 --- a/Documentation/ABI/testing/sysfs-driver-ufs +++ b/Documentation/ABI/testing/sysfs-driver-ufs @@ -1426,6 +1426,17 @@ Description: This entry shows the status of WriteBooster buffer flushing If flushing is enabled, the device executes the flush operation when the command queue is empty. +What: /sys/bus/platform/drivers/ufshcd/*/wb_flush_threshold +What: /sys/bus/platform/devices/*.ufs/wb_flush_threshold +Date: June 2023 +Contact: Lu Hongfei +Description: + wb_flush_threshold represents the threshold for flushing WriteBooster buffer, + whose value expressed in unit of 10% granularity, such as '1' representing 10%, + '2' representing 20%, and so on. + If avail_wb_buff < wb_flush_threshold, it indicates that WriteBooster buffer needs to + be flushed, otherwise it is not necessary. + What: /sys/bus/platform/drivers/ufshcd/*/device_descriptor/hpb_version What: /sys/bus/platform/devices/*.ufs/device_descriptor/hpb_version Date: June 2021 diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-sysfs.c index cdf3d5f2..6c72075 100644 --- a/drivers/ufs/core/ufs-sysfs.c +++ b/drivers/ufs/core/ufs-sysfs.c @@ -298,6 +298,37 @@ out: return res < 0 ? res : count; } +static ssize_t wb_flush_threshold_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ufs_hba *hba = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%u\n", hba->vps->wb_flush_threshold); +} + +static ssize_t wb_flush_threshold_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_flush_threshold; + + if (kstrtouint(buf, 0, &wb_flush_threshold)) + return -EINVAL; + + /* The range of values for wb_flush_threshold is (0,10] */ + if (wb_flush_threshold > UFS_WB_BUF_REMAIN_PERCENT(100) || + wb_flush_threshold == 0) { + dev_err(dev, "The value of wb_flush_threshold is invalid!\n"); + return -EINVAL; + } + + hba->vps->wb_flush_threshold = wb_flush_threshold; + + return count; +} + static DEVICE_ATTR_RW(rpm_lvl); static DEVICE_ATTR_RO(rpm_target_dev_state); static DEVICE_ATTR_RO(rpm_target_link_state); @@ -307,6 +338,7 @@ static DEVICE_ATTR_RO(spm_target_link_state); static DEVICE_ATTR_RW(auto_hibern8); static DEVICE_ATTR_RW(wb_on); static DEVICE_ATTR_RW(enable_wb_buf_flush); +static DEVICE_ATTR_RW(wb_flush_threshold); static struct attribute *ufs_sysfs_ufshcd_attrs[] = { &dev_attr_rpm_lvl.attr, @@ -318,6 +350,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[] = { &dev_attr_auto_hibern8.attr, &dev_attr_wb_on.attr, &dev_attr_enable_wb_buf_flush.attr, + &dev_attr_wb_flush_threshold.attr, NULL }; -- 2.7.4