Adding RTC support for embedded storage device UFS in its driver, it is
important for a few key reasons:
1. Helps with Regular Maintenance:
The RTC provides a basic way to keep track of time, making it useful for
scheduling routine maintenance tasks in the storage device. This includes
things like making sure data is spread
evenly across the storage to extend its life.
2. Figuring Out How Old Data Is:
The RTC helps the device estimate how long ago certain parts of the storage
were last used. This is handy for deciding when to do maintenance tasks to
keep the storage working well over time.
3. Making Devices Last Longer:
By using the RTC for regular upkeep, we can make sure the storage device lasts
longer and stays reliable. This is especially important for devices that need
to work well for a long time.
4.Fitting In with Other Devices:
The inclusion of RTC support aligns with existing UFS specifications (starting
from UFS Spec 2.0) and is consistent with the prevalent industry practice. Many
UFS devices currently on the market utilize RTC for internal timekeeping. By
ensuring compatibility with this widely adopted standard, the embedded storage
device becomes seamlessly integrable with existing hardware and software
ecosystems, reducing the risk of compatibility issues.
In short, adding RTC support to embedded storage device UFS helps with regular
upkeep, extends the device's life, ensures compatibility, and keeps everything
running smoothly with the rest of the system.
Changelog:
v4--v5:
1. Fix coding type issues in patch 2/3
2. Move ufs_rtc_update_work init to ufshcd_init()
3. Move ufshcd_state != UFSHCD_STATE_OPERATIONAL checkup out of ufshcd_is_ufs_dev_busy()
4. Remove inline keyword
v3--v4:
1. Incorporate a check for "Current time precedes previous setting" in ufshcd_update_rtc()
2. Eliminate redundant return value code in ufshcd_update_rtc().
v2--v3:
1. Move ufshcd_is_ufs_dev_busy() to the source file ufshcd.c in patch 1/3.
2. Format commit statement in patch 2/3.
v1--v2:
1. Add a new patch "scsi: ufs: core: Add ufshcd_is_ufs_dev_busy()"
2. RTC periodic update work is disabled by default
3. Address several issues raised by Avri, Bart, and Thomas.
Bean Huo (3):
scsi: ufs: core: Add ufshcd_is_ufs_dev_busy()
scsi: ufs: core: Add UFS RTC support
scsi: ufs: core: Add sysfs node for UFS RTC update
Documentation/ABI/testing/sysfs-driver-ufs | 7 ++
drivers/ufs/core/ufs-sysfs.c | 31 +++++++
drivers/ufs/core/ufshcd.c | 101 +++++++++++++++++++--
include/ufs/ufs.h | 14 +++
include/ufs/ufshcd.h | 4 +
5 files changed, 151 insertions(+), 6 deletions(-)
--
2.34.1
From: Bean Huo <[email protected]>
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 <[email protected]>
Acked-by: Avri Altman <[email protected]>
Reviewed-by: Thomas Weißschuh <[email protected]>
---
Documentation/ABI/testing/sysfs-driver-ufs | 7 +++++
drivers/ufs/core/ufs-sysfs.c | 31 ++++++++++++++++++++++
drivers/ufs/core/ufshcd.c | 11 ++++++--
include/ufs/ufs.h | 1 +
4 files changed, 48 insertions(+), 2 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-driver-ufs b/Documentation/ABI/testing/sysfs-driver-ufs
index b73067bb5ea2..5bf7073b4f75 100644
--- a/Documentation/ABI/testing/sysfs-driver-ufs
+++ b/Documentation/ABI/testing/sysfs-driver-ufs
@@ -1523,3 +1523,10 @@ 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 <[email protected]>
+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.
diff --git a/drivers/ufs/core/ufs-sysfs.c b/drivers/ufs/core/ufs-sysfs.c
index 05b10ca90b50..e6d12289e017 100644
--- a/drivers/ufs/core/ufs-sysfs.c
+++ b/drivers/ufs/core/ufs-sysfs.c
@@ -302,6 +302,35 @@ static ssize_t wb_on_store(struct device *dev, struct device_attribute *attr,
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)
@@ -386,6 +415,7 @@ 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,
@@ -398,6 +428,7 @@ 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
};
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index cda1e1080446..5ebc9c957236 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -8235,9 +8235,9 @@ 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)
@@ -8259,6 +8259,13 @@ 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)
diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
index 7e7169d94596..b6003749bc83 100644
--- a/include/ufs/ufs.h
+++ b/include/ufs/ufs.h
@@ -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;
};
/*
--
2.34.1
From: Bean Huo <[email protected]>
Add Real Time Clock (RTC) support for UFS device. This enhancement is crucial
for the internal maintenance operations of the UFS device. The patch enables
the device to handle both absolute and relative time information. Furthermore,
it includes periodic task to update the RTC in accordance with the UFS Spec,
ensuring the accuracy of RTC information for the device's internal processes.
RTC and qTimestamp serve distinct purposes. The RTC provides a coarse level
of granularity with, at best, approximate single-second resolution. This makes
the RTC well-suited for the device to determine the approximate age of programmed
blocks after being updated by the host. On the other hand, qTimestamp offers
nanosecond granularity and is specifically designed for synchronizing Device
Error Log entries with corresponding host-side logs.
Given that the RTC has been a standard feature since UFS Spec 2.0, and qTimestamp
was introduced in UFS Spec 4.0, the majority of UFS devices currently on the
market rely on RTC. Therefore, it is advisable to continue supporting RTC in
the Linux kernel. This ensures compatibility with the prevailing UFS device
implementations and facilitates seamless integration with existing hardware.
By maintaining support for RTC, we ensure broad compatibility and avoid potential
issues arising from deviations in device specifications across different UFS
versions.
Signed-off-by: Bean Huo <[email protected]>
Signed-off-by: Mike Bi <[email protected]>
Signed-off-by: Luca Porzio <[email protected]>
Acked-by: Avri Altman <[email protected]>
Reviewed-by: Thomas Weißschuh <[email protected]>
---
drivers/ufs/core/ufshcd.c | 83 ++++++++++++++++++++++++++++++++++++++-
include/ufs/ufs.h | 13 ++++++
include/ufs/ufshcd.h | 4 ++
3 files changed, 98 insertions(+), 2 deletions(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 43140699bc29..cda1e1080446 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -99,6 +99,9 @@
/* Polling time to wait for fDeviceInit */
#define FDEVICEINIT_COMPL_TIMEOUT 1500 /* millisecs */
+/* Default RTC update every 10 seconds */
+#define UFS_RTC_UPDATE_INTERVAL_MS (10 * MSEC_PER_SEC)
+
/* UFSHC 4.0 compliant HC support this mode. */
static bool use_mcq_mode = true;
@@ -683,6 +686,8 @@ static void ufshcd_device_reset(struct ufs_hba *hba)
hba->dev_info.wb_enabled = false;
hba->dev_info.wb_buf_flush_enabled = false;
}
+ if (hba->dev_info.rtc_type == UFS_RTC_RELATIVE)
+ hba->dev_info.rtc_time_baseline = 0;
}
if (err != -EOPNOTSUPP)
ufshcd_update_evt_hist(hba, UFS_EVT_DEV_RESET, err);
@@ -8190,6 +8195,72 @@ static void ufs_fixup_device_setup(struct ufs_hba *hba)
ufshcd_vops_fixup_dev_quirks(hba);
}
+static void ufshcd_update_rtc(struct ufs_hba *hba)
+{
+ struct timespec64 ts64;
+ int err;
+ u32 val;
+
+ ktime_get_real_ts64(&ts64);
+
+ if (ts64.tv_sec < hba->dev_info.rtc_time_baseline) {
+ dev_warn_once(hba->dev, "%s: Current time precedes previous setting!\n", __func__);
+ return;
+ }
+
+ /*
+ * The Absolute RTC mode has a 136-year limit, spanning from 2010 to 2146. If a time beyond
+ * 2146 is required, it is recommended to choose the relative RTC mode.
+ */
+ val = ts64.tv_sec - hba->dev_info.rtc_time_baseline;
+
+ ufshcd_rpm_get_sync(hba);
+ err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_WRITE_ATTR, QUERY_ATTR_IDN_SECONDS_PASSED,
+ 0, 0, &val);
+ ufshcd_rpm_put_sync(hba);
+
+ if (err)
+ dev_err(hba->dev, "%s: Failed to update rtc %d\n", __func__, err);
+ else if (hba->dev_info.rtc_type == UFS_RTC_RELATIVE)
+ hba->dev_info.rtc_time_baseline = ts64.tv_sec;
+}
+
+static void ufshcd_rtc_work(struct work_struct *work)
+{
+ struct ufs_hba *hba;
+
+ hba = container_of(to_delayed_work(work), struct ufs_hba, ufs_rtc_update_work);
+
+ /* Update RTC only when there are no requests in progress and UFSHCI is operational */
+ if (!ufshcd_is_ufs_dev_busy(hba) && hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL)
+ ufshcd_update_rtc(hba);
+
+ if (ufshcd_is_ufs_dev_active(hba))
+ schedule_delayed_work(&hba->ufs_rtc_update_work,
+ msecs_to_jiffies(UFS_RTC_UPDATE_INTERVAL_MS));
+}
+
+static void ufs_init_rtc(struct ufs_hba *hba, u8 *desc_buf)
+{
+ u16 periodic_rtc_update = get_unaligned_be16(&desc_buf[DEVICE_DESC_PARAM_FRQ_RTC]);
+ struct ufs_dev_info *dev_info = &hba->dev_info;
+
+ if (periodic_rtc_update & UFS_RTC_TIME_BASELINE) {
+ dev_info->rtc_type = UFS_RTC_ABSOLUTE;
+
+ /*
+ * The concept of measuring time in Linux as the number of seconds elapsed since
+ * 00:00:00 UTC on January 1, 1970, and UFS ABS RTC is elapsed from January 1st
+ * 2010 00:00, here we need to adjust ABS baseline.
+ */
+ dev_info->rtc_time_baseline = mktime64(2010, 1, 1, 0, 0, 0) -
+ mktime64(1970, 1, 1, 0, 0, 0);
+ } else {
+ dev_info->rtc_type = UFS_RTC_RELATIVE;
+ dev_info->rtc_time_baseline = 0;
+ }
+}
+
static int ufs_get_device_desc(struct ufs_hba *hba)
{
int err;
@@ -8242,6 +8313,8 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
ufshcd_temp_notif_probe(hba, desc_buf);
+ ufs_init_rtc(hba, desc_buf);
+
if (hba->ext_iid_sup)
ufshcd_ext_iid_probe(hba, desc_buf);
@@ -8795,6 +8868,8 @@ static int ufshcd_device_init(struct ufs_hba *hba, bool init_dev_params)
ufshcd_force_reset_auto_bkops(hba);
ufshcd_set_timestamp_attr(hba);
+ schedule_delayed_work(&hba->ufs_rtc_update_work,
+ msecs_to_jiffies(UFS_RTC_UPDATE_INTERVAL_MS));
/* Gear up to HS gear if supported */
if (hba->max_pwr_info.is_valid) {
@@ -9752,6 +9827,8 @@ static int __ufshcd_wl_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op)
ret = ufshcd_vops_suspend(hba, pm_op, POST_CHANGE);
if (ret)
goto set_link_active;
+
+ cancel_delayed_work_sync(&hba->ufs_rtc_update_work);
goto out;
set_link_active:
@@ -9846,6 +9923,8 @@ static int __ufshcd_wl_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
if (ret)
goto set_old_link_state;
ufshcd_set_timestamp_attr(hba);
+ schedule_delayed_work(&hba->ufs_rtc_update_work,
+ msecs_to_jiffies(UFS_RTC_UPDATE_INTERVAL_MS));
}
if (ufshcd_keep_autobkops_enabled_except_suspend(hba))
@@ -10542,8 +10621,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
UFS_SLEEP_PWR_MODE,
UIC_LINK_HIBERN8_STATE);
- INIT_DELAYED_WORK(&hba->rpm_dev_flush_recheck_work,
- ufshcd_rpm_dev_flush_recheck_work);
+ INIT_DELAYED_WORK(&hba->rpm_dev_flush_recheck_work, ufshcd_rpm_dev_flush_recheck_work);
+ INIT_DELAYED_WORK(&hba->ufs_rtc_update_work, ufshcd_rtc_work);
/* Set the default auto-hiberate idle timer value to 150 ms */
if (ufshcd_is_auto_hibern8_supported(hba) && !hba->ahit) {
diff --git a/include/ufs/ufs.h b/include/ufs/ufs.h
index e77ab1786856..7e7169d94596 100644
--- a/include/ufs/ufs.h
+++ b/include/ufs/ufs.h
@@ -14,6 +14,7 @@
#include <linux/bitops.h>
#include <linux/types.h>
#include <uapi/scsi/scsi_bsg_ufs.h>
+#include <linux/time64.h>
/*
* Using static_assert() is not allowed in UAPI header files. Hence the check
@@ -551,6 +552,14 @@ struct ufs_vreg_info {
struct ufs_vreg *vdd_hba;
};
+/* UFS device descriptor wPeriodicRTCUpdate bit9 defines RTC time baseline */
+#define UFS_RTC_TIME_BASELINE BIT(9)
+
+enum ufs_rtc_time {
+ UFS_RTC_RELATIVE,
+ UFS_RTC_ABSOLUTE
+};
+
struct ufs_dev_info {
bool f_power_on_wp_en;
/* Keeps information if any of the LU is power on write protected */
@@ -578,6 +587,10 @@ struct ufs_dev_info {
/* UFS EXT_IID Enable */
bool b_ext_iid_en;
+
+ /* UFS RTC */
+ enum ufs_rtc_time rtc_type;
+ time64_t rtc_time_baseline;
};
/*
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index d862c8ddce03..727bdf296b34 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -912,6 +912,8 @@ enum ufshcd_mcq_opr {
* @mcq_base: Multi circular queue registers base address
* @uhq: array of supported hardware queues
* @dev_cmd_queue: Queue for issuing device management commands
+ * @mcq_opr: MCQ operation and runtime registers
+ * @ufs_rtc_update_work: A work for UFS RTC periodic update
*/
struct ufs_hba {
void __iomem *mmio_base;
@@ -1076,6 +1078,8 @@ struct ufs_hba {
struct ufs_hw_queue *uhq;
struct ufs_hw_queue *dev_cmd_queue;
struct ufshcd_mcq_opr_info_t mcq_opr[OPR_MAX];
+
+ struct delayed_work ufs_rtc_update_work;
};
/**
--
2.34.1
From: Bean Huo <[email protected]>
Add helper inline for retrieving whether UFS device is busy or not.
Signed-off-by: Bean Huo <[email protected]>
Reviewed-by: Avri Altman <[email protected]>
Reviewed-by: Thomas Weißschuh <[email protected]>
---
drivers/ufs/core/ufshcd.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index f0b837cb0c2b..43140699bc29 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -235,6 +235,12 @@ ufs_get_desired_pm_lvl_for_dev_link_state(enum ufs_dev_pwr_mode dev_state,
return UFS_PM_LVL_0;
}
+static bool ufshcd_is_ufs_dev_busy(struct ufs_hba *hba)
+{
+ return (hba->clk_gating.active_reqs || hba->outstanding_reqs || hba->outstanding_tasks ||
+ hba->active_uic_cmd || hba->uic_async_done);
+}
+
static const struct ufs_dev_quirk ufs_fixups[] = {
/* UFS cards deviations table */
{ .wmanufacturerid = UFS_VENDOR_MICRON,
@@ -1917,10 +1923,7 @@ static void ufshcd_gate_work(struct work_struct *work)
goto rel_lock;
}
- if (hba->clk_gating.active_reqs
- || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL
- || hba->outstanding_reqs || hba->outstanding_tasks
- || hba->active_uic_cmd || hba->uic_async_done)
+ if (ufshcd_is_ufs_dev_busy(hba) || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL)
goto rel_lock;
spin_unlock_irqrestore(hba->host->host_lock, flags);
--
2.34.1
Bean,
> Adding RTC support for embedded storage device UFS in its driver, it
> is important for a few key reasons:
Applied to 6.8/scsi-staging, thanks!
--
Martin K. Petersen Oracle Linux Engineering
On Tue, 12 Dec 2023 23:08:22 +0100, Bean Huo wrote:
> Adding RTC support for embedded storage device UFS in its driver, it is
> important for a few key reasons:
>
> 1. Helps with Regular Maintenance:
> The RTC provides a basic way to keep track of time, making it useful for
> scheduling routine maintenance tasks in the storage device. This includes
> things like making sure data is spread
> evenly across the storage to extend its life.
>
> [...]
Applied to 6.8/scsi-queue, thanks!
[1/3] scsi: ufs: core: Add ufshcd_is_ufs_dev_busy()
https://git.kernel.org/mkp/scsi/c/9fa268875ca4
[2/3] scsi: ufs: core: Add UFS RTC support
https://git.kernel.org/mkp/scsi/c/6bf999e0eb41
[3/3] scsi: ufs: core: Add sysfs node for UFS RTC update
https://git.kernel.org/mkp/scsi/c/838f595a5672
--
Martin K. Petersen Oracle Linux Engineering