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[PATCH] Revert "scsi: ufs: core: Remove unnecessary block I/O quiesce for clock scaling"

Manivannan Sadhasivam posted 1 patch 16 hours ago 
drivers/ufs/core/ufshcd.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
[PATCH] Revert "scsi: ufs: core: Remove unnecessary block I/O quiesce for clock scaling"
Posted by Manivannan Sadhasivam 16 hours ago 
This reverts commit 85b2b966285498e1b551ac85f02c79cd06c0cff0.

Qcom UFS Host Controllers do not support scaling clocks when the traffic is
ongoing. But the offending commit removed the block I/O quiesce in the
clock scaling path, which causes below UFS failures during clock scaling:

ufshcd-qcom 1d84000.ufshc: ufshcd_check_errors: saved_err 0x80 saved_uic_err 0x0
ufshcd-qcom 1d84000.ufshc: ufshcd_err_handler started; HBA state eh_fatal; powered 1; shutting down 0; saved_err = 0x80; saved_uic_err = 0x0; force_reset = 0
ufshcd-qcom 1d84000.ufshc: pwr ctrl cmd 0x2 with (MIBattribute 0x1571, mode 0x11) completion timeout
ufshcd-qcom 1d84000.ufshc: UFS Host state=3
ufshcd-qcom 1d84000.ufshc: 7 outstanding reqs, tasks=0x0
ufshcd-qcom 1d84000.ufshc: saved_err=0x80, saved_uic_err=0x0
ufshcd-qcom 1d84000.ufshc: Device power mode=1, UIC link state=1
ufshcd-qcom 1d84000.ufshc: PM in progress=0, sys. suspended=0
ufshcd-qcom 1d84000.ufshc: Auto BKOPS=0, Host self-block=0
ufshcd-qcom 1d84000.ufshc: Clk gate=1
ufshcd-qcom 1d84000.ufshc: last_hibern8_exit_tstamp at 196451913 us, hibern8_exit_cnt=20
ufshcd-qcom 1d84000.ufshc: error handling flags=0x0, req. abort count=0
ufshcd-qcom 1d84000.ufshc: hba->ufs_version=0x300, Host capabilities=0x1587031f, caps=0x124f
ufshcd-qcom 1d84000.ufshc: quirks=0x0, dev. quirks=0x310c4
ufshcd-qcom 1d84000.ufshc: UFS dev info: SAMSUNG  KLUDG4UHDB-B2D1  rev 0400
ufshcd-qcom 1d84000.ufshc: clk: core_clk, rate: 300000000
ufshcd-qcom 1d84000.ufshc: clk: core_clk_unipro, rate: 300000000

Hence, revert the commit to bring back UFS on all Qcom platforms.

Reported-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
Closes: https://lore.kernel.org/linux-scsi/al8YkXydXJQZrl_Y@QCOM-aGQu4IUr3Y
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
---
 drivers/ufs/core/ufshcd.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 79331c2bd38d..1a5a851d43b2 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -1445,7 +1445,7 @@ static int ufshcd_scale_gear(struct ufs_hba *hba, u32 target_gear, bool scale_up
  *
  * Return: 0 upon success; -EBUSY upon timeout.
  */
-static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba)
+static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba, u64 timeout_us)
 {
 	int ret = 0;
 	/*
@@ -1453,13 +1453,16 @@ static int ufshcd_clock_scaling_prepare(struct ufs_hba *hba)
 	 * clock scaling is in progress
 	 */
 	mutex_lock(&hba->host->scan_mutex);
+	blk_mq_quiesce_tagset(&hba->host->tag_set);
 	mutex_lock(&hba->wb_mutex);
 	down_write(&hba->clk_scaling_lock);
 
-	if (!hba->clk_scaling.is_allowed) {
+	if (!hba->clk_scaling.is_allowed ||
+	    ufshcd_wait_for_pending_cmds(hba, timeout_us)) {
 		ret = -EBUSY;
 		up_write(&hba->clk_scaling_lock);
 		mutex_unlock(&hba->wb_mutex);
+		blk_mq_unquiesce_tagset(&hba->host->tag_set);
 		mutex_unlock(&hba->host->scan_mutex);
 		goto out;
 	}
@@ -1475,6 +1478,7 @@ static void ufshcd_clock_scaling_unprepare(struct ufs_hba *hba, int err)
 {
 	up_write(&hba->clk_scaling_lock);
 	mutex_unlock(&hba->wb_mutex);
+	blk_mq_unquiesce_tagset(&hba->host->tag_set);
 	mutex_unlock(&hba->host->scan_mutex);
 
 	/* Enable Write Booster if current gear requires it else disable it */
@@ -1502,7 +1506,7 @@ static int ufshcd_devfreq_scale(struct ufs_hba *hba, unsigned long freq,
 
 	new_gear = ufshcd_vops_freq_to_gear_speed(hba, freq);
 
-	ret = ufshcd_clock_scaling_prepare(hba);
+	ret = ufshcd_clock_scaling_prepare(hba, 1 * USEC_PER_SEC);
 	if (ret)
 		return ret;
 
-- 
2.43.0
Re: [PATCH] Revert "scsi: ufs: core: Remove unnecessary block I/O quiesce for clock scaling"
Posted by Shawn Guo 3 hours ago 
On Thu, Jul 23, 2026 at 02:47:33PM +0200, Manivannan Sadhasivam wrote:
> This reverts commit 85b2b966285498e1b551ac85f02c79cd06c0cff0.
> 
> Qcom UFS Host Controllers do not support scaling clocks when the traffic is
> ongoing. But the offending commit removed the block I/O quiesce in the
> clock scaling path, which causes below UFS failures during clock scaling:
> 
> ufshcd-qcom 1d84000.ufshc: ufshcd_check_errors: saved_err 0x80 saved_uic_err 0x0
> ufshcd-qcom 1d84000.ufshc: ufshcd_err_handler started; HBA state eh_fatal; powered 1; shutting down 0; saved_err = 0x80; saved_uic_err = 0x0; force_reset = 0
> ufshcd-qcom 1d84000.ufshc: pwr ctrl cmd 0x2 with (MIBattribute 0x1571, mode 0x11) completion timeout
> ufshcd-qcom 1d84000.ufshc: UFS Host state=3
> ufshcd-qcom 1d84000.ufshc: 7 outstanding reqs, tasks=0x0
> ufshcd-qcom 1d84000.ufshc: saved_err=0x80, saved_uic_err=0x0
> ufshcd-qcom 1d84000.ufshc: Device power mode=1, UIC link state=1
> ufshcd-qcom 1d84000.ufshc: PM in progress=0, sys. suspended=0
> ufshcd-qcom 1d84000.ufshc: Auto BKOPS=0, Host self-block=0
> ufshcd-qcom 1d84000.ufshc: Clk gate=1
> ufshcd-qcom 1d84000.ufshc: last_hibern8_exit_tstamp at 196451913 us, hibern8_exit_cnt=20
> ufshcd-qcom 1d84000.ufshc: error handling flags=0x0, req. abort count=0
> ufshcd-qcom 1d84000.ufshc: hba->ufs_version=0x300, Host capabilities=0x1587031f, caps=0x124f
> ufshcd-qcom 1d84000.ufshc: quirks=0x0, dev. quirks=0x310c4
> ufshcd-qcom 1d84000.ufshc: UFS dev info: SAMSUNG  KLUDG4UHDB-B2D1  rev 0400
> ufshcd-qcom 1d84000.ufshc: clk: core_clk, rate: 300000000
> ufshcd-qcom 1d84000.ufshc: clk: core_clk_unipro, rate: 300000000
> 
> Hence, revert the commit to bring back UFS on all Qcom platforms.
> 
> Reported-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
> Closes: https://lore.kernel.org/linux-scsi/al8YkXydXJQZrl_Y@QCOM-aGQu4IUr3Y
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>

Tested-by: Shawn Guo <shengchao.guo@oss.qualcomm.com> # Qualcomm Nord SoC
Re: [PATCH] Revert "scsi: ufs: core: Remove unnecessary block I/O quiesce for clock scaling"
Posted by Bart Van Assche 9 hours ago 
On 7/23/26 5:47 AM, Manivannan Sadhasivam wrote:
> This reverts commit 85b2b966285498e1b551ac85f02c79cd06c0cff0.
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Re: [PATCH] Revert "scsi: ufs: core: Remove unnecessary block I/O quiesce for clock scaling"
Posted by Konrad Dybcio 15 hours ago 
On 7/23/26 2:47 PM, Manivannan Sadhasivam wrote:
> This reverts commit 85b2b966285498e1b551ac85f02c79cd06c0cff0.
> 
> Qcom UFS Host Controllers do not support scaling clocks when the traffic is
> ongoing. But the offending commit removed the block I/O quiesce in the
> clock scaling path, which causes below UFS failures during clock scaling:
> 
> ufshcd-qcom 1d84000.ufshc: ufshcd_check_errors: saved_err 0x80 saved_uic_err 0x0
> ufshcd-qcom 1d84000.ufshc: ufshcd_err_handler started; HBA state eh_fatal; powered 1; shutting down 0; saved_err = 0x80; saved_uic_err = 0x0; force_reset = 0
> ufshcd-qcom 1d84000.ufshc: pwr ctrl cmd 0x2 with (MIBattribute 0x1571, mode 0x11) completion timeout
> ufshcd-qcom 1d84000.ufshc: UFS Host state=3
> ufshcd-qcom 1d84000.ufshc: 7 outstanding reqs, tasks=0x0
> ufshcd-qcom 1d84000.ufshc: saved_err=0x80, saved_uic_err=0x0
> ufshcd-qcom 1d84000.ufshc: Device power mode=1, UIC link state=1
> ufshcd-qcom 1d84000.ufshc: PM in progress=0, sys. suspended=0
> ufshcd-qcom 1d84000.ufshc: Auto BKOPS=0, Host self-block=0
> ufshcd-qcom 1d84000.ufshc: Clk gate=1
> ufshcd-qcom 1d84000.ufshc: last_hibern8_exit_tstamp at 196451913 us, hibern8_exit_cnt=20
> ufshcd-qcom 1d84000.ufshc: error handling flags=0x0, req. abort count=0
> ufshcd-qcom 1d84000.ufshc: hba->ufs_version=0x300, Host capabilities=0x1587031f, caps=0x124f
> ufshcd-qcom 1d84000.ufshc: quirks=0x0, dev. quirks=0x310c4
> ufshcd-qcom 1d84000.ufshc: UFS dev info: SAMSUNG  KLUDG4UHDB-B2D1  rev 0400
> ufshcd-qcom 1d84000.ufshc: clk: core_clk, rate: 300000000
> ufshcd-qcom 1d84000.ufshc: clk: core_clk_unipro, rate: 300000000
> 
> Hence, revert the commit to bring back UFS on all Qcom platforms.
> 
> Reported-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
> Closes: https://lore.kernel.org/linux-scsi/al8YkXydXJQZrl_Y@QCOM-aGQu4IUr3Y
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
> ---

Tested-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> # SC8280XP CRD

Konrad
Re: [PATCH] Revert "scsi: ufs: core: Remove unnecessary block I/O quiesce for clock scaling"
Posted by Peter Wang (王信友) 15 hours ago 
On Thu, 2026-07-23 at 14:47 +0200, Manivannan Sadhasivam wrote:
> This reverts commit 85b2b966285498e1b551ac85f02c79cd06c0cff0.
> 
> Qcom UFS Host Controllers do not support scaling clocks when the
> traffic is
> ongoing. But the offending commit removed the block I/O quiesce in
> the
> clock scaling path, which causes below UFS failures during clock
> scaling:
> 
> ufshcd-qcom 1d84000.ufshc: ufshcd_check_errors: saved_err 0x80
> saved_uic_err 0x0
> ufshcd-qcom 1d84000.ufshc: ufshcd_err_handler started; HBA state
> eh_fatal; powered 1; shutting down 0; saved_err = 0x80; saved_uic_err
> = 0x0; force_reset = 0
> ufshcd-qcom 1d84000.ufshc: pwr ctrl cmd 0x2 with (MIBattribute
> 0x1571, mode 0x11) completion timeout
> ufshcd-qcom 1d84000.ufshc: UFS Host state=3
> ufshcd-qcom 1d84000.ufshc: 7 outstanding reqs, tasks=0x0
> ufshcd-qcom 1d84000.ufshc: saved_err=0x80, saved_uic_err=0x0
> ufshcd-qcom 1d84000.ufshc: Device power mode=1, UIC link state=1
> ufshcd-qcom 1d84000.ufshc: PM in progress=0, sys. suspended=0
> ufshcd-qcom 1d84000.ufshc: Auto BKOPS=0, Host self-block=0
> ufshcd-qcom 1d84000.ufshc: Clk gate=1
> ufshcd-qcom 1d84000.ufshc: last_hibern8_exit_tstamp at 196451913 us,
> hibern8_exit_cnt=20
> ufshcd-qcom 1d84000.ufshc: error handling flags=0x0, req. abort
> count=0
> ufshcd-qcom 1d84000.ufshc: hba->ufs_version=0x300, Host
> capabilities=0x1587031f, caps=0x124f
> ufshcd-qcom 1d84000.ufshc: quirks=0x0, dev. quirks=0x310c4
> ufshcd-qcom 1d84000.ufshc: UFS dev info: SAMSUNG  KLUDG4UHDB-B2D1 
> rev 0400
> ufshcd-qcom 1d84000.ufshc: clk: core_clk, rate: 300000000
> ufshcd-qcom 1d84000.ufshc: clk: core_clk_unipro, rate: 300000000
> 
> Hence, revert the commit to bring back UFS on all Qcom platforms.
> 
> Reported-by: Shawn Guo <shengchao.guo@oss.qualcomm.com>
> Closes:
> https://lore.kernel.org/linux-scsi/al8YkXydXJQZrl_Y@QCOM-aGQu4IUr3Y
> Signed-off-by: Manivannan Sadhasivam
> <manivannan.sadhasivam@oss.qualcomm.com>
> ---

Reviewed-by: Peter Wang <peter.wang@mediatek.com>

Patchew 2.1-devel-ea86937

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