scsi: ufs: host: mediatek: Correct clock scaling with PM QoS flow

Correct clock scaling with PM QoS during suspend and resume.  Ensure PM
QoS is released during suspend if scaling up and re-applied after
resume. This prevents performance issues and maintains proper power
management.

Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Chun-Hung Wu <chun-hung.wu@mediatek.com>
Link: https://patch.msgid.link/20250924094527.2992256-2-peter.wang@mediatek.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 8339fec975b9230c67cc6c5338fed2fbf01af2af..2dadb749e2130d250656cdee9ccdf93890d1da26 100644 (file)
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -1076,7 +1076,7 @@ void ufshcd_pm_qos_exit(struct ufs_hba *hba)
  * @hba: per adapter instance
  * @on: If True, vote for perf PM QoS mode otherwise power save mode
  */
-static void ufshcd_pm_qos_update(struct ufs_hba *hba, bool on)
+void ufshcd_pm_qos_update(struct ufs_hba *hba, bool on)
 {
        guard(mutex)(&hba->pm_qos_mutex);
 
@@ -1085,6 +1085,7 @@ static void ufshcd_pm_qos_update(struct ufs_hba *hba, bool on)
 
        cpu_latency_qos_update_request(&hba->pm_qos_req, on ? 0 : PM_QOS_DEFAULT_VALUE);
 }
+EXPORT_SYMBOL_GPL(ufshcd_pm_qos_update);
 
 /**
  * ufshcd_set_clk_freq - set UFS controller clock frequencies

diff --git a/drivers/ufs/host/ufs-mediatek.c b/drivers/ufs/host/ufs-mediatek.c
index 758a393a9de1a280d5604b0bd045d65f5f548f00..009031fee7449964e85312cd5174de8dd6ace075 100644 (file)
--- a/drivers/ufs/host/ufs-mediatek.c
+++ b/drivers/ufs/host/ufs-mediatek.c
@@ -1744,6 +1744,7 @@ static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
 {
        int err;
        struct arm_smccc_res res;
+       struct ufs_mtk_host *host = ufshcd_get_variant(hba);
 
        if (status == PRE_CHANGE) {
                if (ufshcd_is_auto_hibern8_supported(hba))
@@ -1773,6 +1774,10 @@ static int ufs_mtk_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
 
        ufs_mtk_sram_pwr_ctrl(false, res);
 
+       /* Release pm_qos if in scale-up mode during suspend */
+       if (ufshcd_is_clkscaling_supported(hba) && (host->clk_scale_up))
+               ufshcd_pm_qos_update(hba, false);
+
        return 0;
 fail:
        /*
@@ -1788,6 +1793,7 @@ static int ufs_mtk_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
        int err;
        struct arm_smccc_res res;
+       struct ufs_mtk_host *host = ufshcd_get_variant(hba);
 
        if (hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL)
                ufs_mtk_dev_vreg_set_lpm(hba, false);
@@ -1798,6 +1804,10 @@ static int ufs_mtk_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
        if (err)
                goto fail;
 
+       /* Request pm_qos if in scale-up mode after resume */
+       if (ufshcd_is_clkscaling_supported(hba) && (host->clk_scale_up))
+               ufshcd_pm_qos_update(hba, true);
+
        if (ufshcd_is_link_hibern8(hba)) {
                err = ufs_mtk_link_set_hpm(hba);
                if (err)

diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index 9425cfd9d00eb0671566cfad2e4b8ad67e4802b2..ce7301d63c5ceb815e550f6712c14c97b260ed3d 100644 (file)
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -1487,5 +1487,6 @@ int ufshcd_write_ee_control(struct ufs_hba *hba);
 int ufshcd_update_ee_control(struct ufs_hba *hba, u16 *mask,
                             const u16 *other_mask, u16 set, u16 clr);
 void ufshcd_force_error_recovery(struct ufs_hba *hba);
+void ufshcd_pm_qos_update(struct ufs_hba *hba, bool on);
 
 #endif /* End of Header */