diff mbox series

[V1,1/2] scsi: ufs: qcom : Refactor phy_power_on/off calls

Message ID 20240112153348.2778-2-quic_nitirawa@quicinc.com
State Changes Requested
Headers show
Series Refactor phy powerup sequence | expand

Commit Message

Nitin Rawat Jan. 12, 2024, 3:33 p.m. UTC 
Commit 3f6d1767b1a0 ("phy: ufs-qcom: Refactor all init steps into
phy_poweron") removes the phy_power_on/off from ufs_qcom_setup_clocks
to suspend/resume func.

To have a better power saving, remove the phy_power_on/off calls from
resume/suspend path and put them back to ufs_qcom_setup_clocks, so that
PHY's regulators & clks can be turned on/off along with UFS's clocks.

Since phy phy_power_on is separated out from phy calibrate, make
separate calls to phy_power_on and phy_calibrate calls from ufs qcom
driver.

Also add a mutex lock to protect the usage of is_phy_pwr_on against
possible racing.

Co-developed-by: Can Guo <quic_cang@quicinc.com>
Signed-off-by: Can Guo <quic_cang@quicinc.com>
Co-developed-by: Naveen Kumar Goud Arepalli <quic_narepall@quicinc.com>
Signed-off-by: Naveen Kumar Goud Arepalli <quic_narepall@quicinc.com>
Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com>
---
 drivers/ufs/host/ufs-qcom.c | 104 +++++++++++++++++++++++-------------
 drivers/ufs/host/ufs-qcom.h |   4 ++
 2 files changed, 72 insertions(+), 36 deletions(-)

--
2.43.0

Comments

Konrad Dybcio Jan. 12, 2024, 10:28 p.m. UTC | #1 
On 12.01.2024 16:33, Nitin Rawat wrote:
> Commit 3f6d1767b1a0 ("phy: ufs-qcom: Refactor all init steps into
> phy_poweron") removes the phy_power_on/off from ufs_qcom_setup_clocks
> to suspend/resume func.
> 
> To have a better power saving, remove the phy_power_on/off calls from
> resume/suspend path and put them back to ufs_qcom_setup_clocks, so that
> PHY's regulators & clks can be turned on/off along with UFS's clocks.
> 
> Since phy phy_power_on is separated out from phy calibrate, make
> separate calls to phy_power_on and phy_calibrate calls from ufs qcom
> driver.
> 
> Also add a mutex lock to protect the usage of is_phy_pwr_on against
> possible racing.
> 
> Co-developed-by: Can Guo <quic_cang@quicinc.com>
> Signed-off-by: Can Guo <quic_cang@quicinc.com>
> Co-developed-by: Naveen Kumar Goud Arepalli <quic_narepall@quicinc.com>
> Signed-off-by: Naveen Kumar Goud Arepalli <quic_narepall@quicinc.com>
> Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com>
> ---
>  drivers/ufs/host/ufs-qcom.c | 104 +++++++++++++++++++++++-------------
>  drivers/ufs/host/ufs-qcom.h |   4 ++
>  2 files changed, 72 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> index 39eef470f8fa..2721a30f0db8 100644
> --- a/drivers/ufs/host/ufs-qcom.c
> +++ b/drivers/ufs/host/ufs-qcom.c
> @@ -338,6 +338,46 @@ static u32 ufs_qcom_get_hs_gear(struct ufs_hba *hba)
>  	return UFS_HS_G3;
>  }
> 
> +static int ufs_qcom_phy_power_on(struct ufs_hba *hba)
> +{
> +	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> +	struct phy *phy = host->generic_phy;
> +	int ret = 0;
> +
> +	mutex_lock(&host->phy_mutex);

guard(mutex)(&host->phy_mutex);

and you can drop the _unlock calls

> +	if (!host->is_phy_pwr_on) {
> +		ret = phy_power_on(phy);
> +		if (ret) {
> +			mutex_unlock(&host->phy_mutex);
> +			return ret;

And with the _unlock now being unnecessary, you can rewrite this
as:

if (!host->is_phy_pwr_on) {
	ret = phy_power_on(phy);
	if (!ret)
		host->is_phy_pwr_on = true;
}

return ret
> +		}
> +		host->is_phy_pwr_on = true;
> +	}
> +	mutex_unlock(&host->phy_mutex);
> +
> +	return ret;
> +}

[...]

>  static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
>  {
>  	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> @@ -378,13 +418,18 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
>  		goto out_disable_phy;
> 
>  	/* power on phy - start serdes and phy's power and clocks */
> -	ret = phy_power_on(phy);
> +	ret = ufs_qcom_phy_power_on(hba);
>  	if (ret) {
>  		dev_err(hba->dev, "%s: phy power on failed, ret = %d\n",
>  			__func__, ret);
>  		goto out_disable_phy;
>  	}
> 
> +	ret = phy_calibrate(phy);
> +	if (ret) {
> +		dev_err(hba->dev, "%s: Failed to calibrate PHY %d\n",
> +				  __func__, ret);
> +	}

You can drop the overly verbose __func__, unwrap the line and remove the
curly braces, similar for dev_err-s below

Actually, shouldn't this error out if calibrate fails??

Konrad
Manivannan Sadhasivam Jan. 24, 2024, 8:22 a.m. UTC | #2 
On Fri, Jan 12, 2024 at 09:03:47PM +0530, Nitin Rawat wrote:
> Commit 3f6d1767b1a0 ("phy: ufs-qcom: Refactor all init steps into
> phy_poweron") removes the phy_power_on/off from ufs_qcom_setup_clocks

s/removes/moved

> to suspend/resume func.
> 
> To have a better power saving, remove the phy_power_on/off calls from
> resume/suspend path and put them back to ufs_qcom_setup_clocks, so that
> PHY's regulators & clks can be turned on/off along with UFS's clocks.
> 
> Since phy phy_power_on is separated out from phy calibrate, make
> separate calls to phy_power_on and phy_calibrate calls from ufs qcom
> driver.
> 

Above change should be in a separate patch.

> Also add a mutex lock to protect the usage of is_phy_pwr_on against
> possible racing.
> 
> Co-developed-by: Can Guo <quic_cang@quicinc.com>
> Signed-off-by: Can Guo <quic_cang@quicinc.com>
> Co-developed-by: Naveen Kumar Goud Arepalli <quic_narepall@quicinc.com>
> Signed-off-by: Naveen Kumar Goud Arepalli <quic_narepall@quicinc.com>
> Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com>
> ---
>  drivers/ufs/host/ufs-qcom.c | 104 +++++++++++++++++++++++-------------
>  drivers/ufs/host/ufs-qcom.h |   4 ++
>  2 files changed, 72 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> index 39eef470f8fa..2721a30f0db8 100644
> --- a/drivers/ufs/host/ufs-qcom.c
> +++ b/drivers/ufs/host/ufs-qcom.c
> @@ -338,6 +338,46 @@ static u32 ufs_qcom_get_hs_gear(struct ufs_hba *hba)
>  	return UFS_HS_G3;
>  }
> 
> +static int ufs_qcom_phy_power_on(struct ufs_hba *hba)
> +{
> +	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> +	struct phy *phy = host->generic_phy;
> +	int ret = 0;
> +
> +	mutex_lock(&host->phy_mutex);

You do not need mutex to protect a variable. If you want to ensure that the
access to the flag is atomic, you can use test_and_{set/clear}_bit helpers.

> +	if (!host->is_phy_pwr_on) {
> +		ret = phy_power_on(phy);
> +		if (ret) {
> +			mutex_unlock(&host->phy_mutex);
> +			return ret;
> +		}
> +		host->is_phy_pwr_on = true;
> +	}
> +	mutex_unlock(&host->phy_mutex);
> +
> +	return ret;
> +}
> +
> +static int ufs_qcom_phy_power_off(struct ufs_hba *hba)
> +{
> +	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> +	struct phy *phy = host->generic_phy;
> +	int ret = 0;
> +
> +	mutex_lock(&host->phy_mutex);
> +	if (host->is_phy_pwr_on) {
> +		ret = phy_power_off(phy);
> +		if (ret) {
> +			mutex_unlock(&host->phy_mutex);
> +			return ret;
> +		}
> +		host->is_phy_pwr_on = false;
> +	}
> +	mutex_unlock(&host->phy_mutex);
> +
> +	return ret;
> +}
> +
>  static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
>  {
>  	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> @@ -378,13 +418,18 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
>  		goto out_disable_phy;
> 
>  	/* power on phy - start serdes and phy's power and clocks */
> -	ret = phy_power_on(phy);
> +	ret = ufs_qcom_phy_power_on(hba);
>  	if (ret) {
>  		dev_err(hba->dev, "%s: phy power on failed, ret = %d\n",
>  			__func__, ret);
>  		goto out_disable_phy;
>  	}
> 
> +	ret = phy_calibrate(phy);
> +	if (ret) {
> +		dev_err(hba->dev, "%s: Failed to calibrate PHY %d\n",
> +				  __func__, ret);

Even though the driver already has a lot of "__func__" to print the function
names in error log, please do not add more. I will get rid of the existing ones
at some point.

- Mani
diff mbox series

Patch

diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index 39eef470f8fa..2721a30f0db8 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -338,6 +338,46 @@  static u32 ufs_qcom_get_hs_gear(struct ufs_hba *hba)
 	return UFS_HS_G3;
 }

+static int ufs_qcom_phy_power_on(struct ufs_hba *hba)
+{
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	struct phy *phy = host->generic_phy;
+	int ret = 0;
+
+	mutex_lock(&host->phy_mutex);
+	if (!host->is_phy_pwr_on) {
+		ret = phy_power_on(phy);
+		if (ret) {
+			mutex_unlock(&host->phy_mutex);
+			return ret;
+		}
+		host->is_phy_pwr_on = true;
+	}
+	mutex_unlock(&host->phy_mutex);
+
+	return ret;
+}
+
+static int ufs_qcom_phy_power_off(struct ufs_hba *hba)
+{
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	struct phy *phy = host->generic_phy;
+	int ret = 0;
+
+	mutex_lock(&host->phy_mutex);
+	if (host->is_phy_pwr_on) {
+		ret = phy_power_off(phy);
+		if (ret) {
+			mutex_unlock(&host->phy_mutex);
+			return ret;
+		}
+		host->is_phy_pwr_on = false;
+	}
+	mutex_unlock(&host->phy_mutex);
+
+	return ret;
+}
+
 static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
@@ -378,13 +418,18 @@  static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 		goto out_disable_phy;

 	/* power on phy - start serdes and phy's power and clocks */
-	ret = phy_power_on(phy);
+	ret = ufs_qcom_phy_power_on(hba);
 	if (ret) {
 		dev_err(hba->dev, "%s: phy power on failed, ret = %d\n",
 			__func__, ret);
 		goto out_disable_phy;
 	}

+	ret = phy_calibrate(phy);
+	if (ret) {
+		dev_err(hba->dev, "%s: Failed to calibrate PHY %d\n",
+				  __func__, ret);
+	}
 	ufs_qcom_select_unipro_mode(host);

 	return 0;
@@ -557,26 +602,17 @@  static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
 	enum ufs_notify_change_status status)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-	struct phy *phy = host->generic_phy;

 	if (status == PRE_CHANGE)
 		return 0;

-	if (ufs_qcom_is_link_off(hba)) {
-		/*
-		 * Disable the tx/rx lane symbol clocks before PHY is
-		 * powered down as the PLL source should be disabled
-		 * after downstream clocks are disabled.
-		 */
+	if (!ufs_qcom_is_link_active(hba))
 		ufs_qcom_disable_lane_clks(host);
-		phy_power_off(phy);

-		/* reset the connected UFS device during power down */
-		ufs_qcom_device_reset_ctrl(hba, true);

-	} else if (!ufs_qcom_is_link_active(hba)) {
-		ufs_qcom_disable_lane_clks(host);
-	}
+	/* reset the connected UFS device during power down */
+	if (ufs_qcom_is_link_off(hba) && host->device_reset)
+		ufs_qcom_device_reset_ctrl(hba, true);

 	return ufs_qcom_ice_suspend(host);
 }
@@ -584,26 +620,11 @@  static int ufs_qcom_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op,
 static int ufs_qcom_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-	struct phy *phy = host->generic_phy;
 	int err;

-	if (ufs_qcom_is_link_off(hba)) {
-		err = phy_power_on(phy);
-		if (err) {
-			dev_err(hba->dev, "%s: failed PHY power on: %d\n",
-				__func__, err);
-			return err;
-		}
-
-		err = ufs_qcom_enable_lane_clks(host);
-		if (err)
-			return err;
-
-	} else if (!ufs_qcom_is_link_active(hba)) {
-		err = ufs_qcom_enable_lane_clks(host);
-		if (err)
-			return err;
-	}
+	err = ufs_qcom_enable_lane_clks(host);
+	if (err)
+		return err;

 	return ufs_qcom_ice_resume(host);
 }
@@ -908,6 +929,7 @@  static int ufs_qcom_setup_clocks(struct ufs_hba *hba, bool on,
 				 enum ufs_notify_change_status status)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	int err;

 	/*
 	 * In case ufs_qcom_init() is not yet done, simply ignore.
@@ -926,10 +948,22 @@  static int ufs_qcom_setup_clocks(struct ufs_hba *hba, bool on,
 				/* disable device ref_clk */
 				ufs_qcom_dev_ref_clk_ctrl(host, false);
 			}
+			err = ufs_qcom_phy_power_off(hba);
+			if (err) {
+				dev_err(hba->dev, "%s: phy power off failed, ret=%d\n",
+						__func__, err);
+					return err;
+			}
 		}
 		break;
 	case POST_CHANGE:
 		if (on) {
+			err = ufs_qcom_phy_power_on(hba);
+			if (err) {
+				dev_err(hba->dev, "%s: phy power on failed, ret = %d\n",
+						__func__, err);
+				return err;
+			}
 			/* enable the device ref clock for HS mode*/
 			if (ufshcd_is_hs_mode(&hba->pwr_info))
 				ufs_qcom_dev_ref_clk_ctrl(host, true);
@@ -1110,7 +1144,7 @@  static void ufs_qcom_exit(struct ufs_hba *hba)
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);

 	ufs_qcom_disable_lane_clks(host);
-	phy_power_off(host->generic_phy);
+	ufs_qcom_phy_power_off(hba);
 	phy_exit(host->generic_phy);
 }

@@ -1536,9 +1570,7 @@  static void ufs_qcom_config_scaling_param(struct ufs_hba *hba,

 static void ufs_qcom_reinit_notify(struct ufs_hba *hba)
 {
-	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-
-	phy_power_off(host->generic_phy);
+	ufs_qcom_phy_power_off(hba);
 }

 /* Resources */
diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h
index 9dd9a391ebb7..241dba01672e 100644
--- a/drivers/ufs/host/ufs-qcom.h
+++ b/drivers/ufs/host/ufs-qcom.h
@@ -215,6 +215,10 @@  struct ufs_qcom_host {
 	u32 phy_gear;

 	bool esi_enabled;
+	/* flag to check if phy is powered on */
+	bool is_phy_pwr_on;
+	/* Protect the usage of is_phy_pwr_on against racing */
+	struct mutex phy_mutex;
 };

 static inline u32