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scsi: ufs: core: Add sysfs node for UFS RTC update

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Introduce a sysfs node named 'rtc_update_ms' within the kernel, enabling
user to adjust the RTC periodic update frequency to suit the specific
requirements of the system and UFS. Also, this patch allows the user to
disable/enable periodic update RTC in the UFS idle time.

Signed-off-by: Bean Huo <beanhuo@micron.com>
Link: https://lore.kernel.org/r/20231212220825.85255-4-beanhuo@iokpp.de
Acked-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Bean Huo 2023-12-12 23:08:25 +01:00 committed by Martin K. Petersen
parent 6bf999e0eb
commit 838f595a56
4 changed files with 48 additions and 2 deletions
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7
Documentation/ABI/testing/sysfs-driver-ufs
View File

@ -1474,3 +1474,10 @@ Description: Indicates status of Write Booster.
The file is read only.
What: /sys/bus/platform/drivers/ufshcd/*/rtc_update_ms
What: /sys/bus/platform/devices/*.ufs/rtc_update_ms
Date: November 2023
Contact: Bean Huo <beanhuo@micron.com>
Description:
rtc_update_ms indicates how often the host should synchronize or update the
UFS RTC. If set to 0, this will disable UFS RTC periodic update.

31
drivers/ufs/core/ufs-sysfs.c
View File

@ -255,6 +255,35 @@ out:
return res < 0 ? res : count;
}
static ssize_t rtc_update_ms_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->dev_info.rtc_update_period);
}
static ssize_t rtc_update_ms_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct ufs_hba *hba = dev_get_drvdata(dev);
unsigned int ms;
bool resume_period_update = false;
if (kstrtouint(buf, 0, &ms))
return -EINVAL;
if (!hba->dev_info.rtc_update_period && ms > 0)
resume_period_update = true;
/* Minimum and maximum update frequency should be synchronized with all UFS vendors */
hba->dev_info.rtc_update_period = ms;
if (resume_period_update)
schedule_delayed_work(&hba->ufs_rtc_update_work,
msecs_to_jiffies(hba->dev_info.rtc_update_period));
return count;
}
static ssize_t enable_wb_buf_flush_show(struct device *dev,
struct device_attribute *attr,
char *buf)
@ -339,6 +368,7 @@ 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 DEVICE_ATTR_RW(rtc_update_ms);
static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
&dev_attr_rpm_lvl.attr,
@ -351,6 +381,7 @@ static struct attribute *ufs_sysfs_ufshcd_attrs[] = {
&dev_attr_wb_on.attr,
&dev_attr_enable_wb_buf_flush.attr,
&dev_attr_wb_flush_threshold.attr,
&dev_attr_rtc_update_ms.attr,
NULL
};

11
drivers/ufs/core/ufshcd.c
View File

@ -8233,9 +8233,9 @@ static void ufshcd_rtc_work(struct work_struct *work)
if (!ufshcd_is_ufs_dev_busy(hba) && hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL)
ufshcd_update_rtc(hba);
if (ufshcd_is_ufs_dev_active(hba))
if (ufshcd_is_ufs_dev_active(hba) && hba->dev_info.rtc_update_period)
schedule_delayed_work(&hba->ufs_rtc_update_work,
msecs_to_jiffies(UFS_RTC_UPDATE_INTERVAL_MS));
msecs_to_jiffies(hba->dev_info.rtc_update_period));
}
static void ufs_init_rtc(struct ufs_hba *hba, u8 *desc_buf)
@ -8257,6 +8257,13 @@ static void ufs_init_rtc(struct ufs_hba *hba, u8 *desc_buf)
dev_info->rtc_type = UFS_RTC_RELATIVE;
dev_info->rtc_time_baseline = 0;
}
/*
* We ignore TIME_PERIOD defined in wPeriodicRTCUpdate because Spec does not clearly state
* how to calculate the specific update period for each time unit. And we disable periodic
* RTC update work, let user configure by sysfs node according to specific circumstance.
*/
dev_info->rtc_update_period = 0;
}
static int ufs_get_device_desc(struct ufs_hba *hba)

1
include/ufs/ufs.h
View File

@ -591,6 +591,7 @@ struct ufs_dev_info {
/* UFS RTC */
enum ufs_rtc_time rtc_type;
time64_t rtc_time_baseline;
u32 rtc_update_period;
};
/*