diff mbox series

[V2,3/6] phy: qcom-qmp-ufs: Refactor UFS PHY reset

Message ID 20250318144944.19749-4-quic_nitirawa@quicinc.com
State New
Headers show
Series Refactor phy powerup sequence | expand

Commit Message

Nitin Rawat March 18, 2025, 2:49 p.m. UTC 
Refactor the UFS PHY reset handling to parse the reset logic only once
during probe, instead of every resume.

Move the UFS PHY reset parsing logic from qmp_phy_power_on to
qmp_ufs_probe to avoid unnecessary parsing during resume.

Co-developed-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com>
Signed-off-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com>
Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com>
---
 drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 104 ++++++++++++------------
 1 file changed, 50 insertions(+), 54 deletions(-)

--
2.48.1

Comments

Neil Armstrong March 18, 2025, 3:13 p.m. UTC | #1 
On 18/03/2025 15:49, Nitin Rawat wrote:
> Refactor the UFS PHY reset handling to parse the reset logic only once
> during probe, instead of every resume.
> 
> Move the UFS PHY reset parsing logic from qmp_phy_power_on to
> qmp_ufs_probe to avoid unnecessary parsing during resume.
> 
> Co-developed-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com>
> Signed-off-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com>
> Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com>
> ---
>   drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 104 ++++++++++++------------
>   1 file changed, 50 insertions(+), 54 deletions(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> index 0089ee80f852..3a80c2c110d2 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> @@ -1757,32 +1757,6 @@ static void qmp_ufs_init_registers(struct qmp_ufs *qmp, const struct qmp_phy_cfg
>   	qmp_ufs_init_all(qmp, &cfg->tbls_hs_b);
>   }
> 
> -static int qmp_ufs_com_init(struct qmp_ufs *qmp)
> -{
> -	const struct qmp_phy_cfg *cfg = qmp->cfg;
> -	void __iomem *pcs = qmp->pcs;
> -	int ret;
> -
> -	ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
> -	if (ret) {
> -		dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
> -		return ret;
> -	}
> -
> -	ret = clk_bulk_prepare_enable(qmp->num_clks, qmp->clks);
> -	if (ret)
> -		goto err_disable_regulators;
> -
> -	qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], SW_PWRDN);
> -
> -	return 0;
> -
> -err_disable_regulators:
> -	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
> -
> -	return ret;
> -}
> -
>   static int qmp_ufs_com_exit(struct qmp_ufs *qmp)
>   {
>   	const struct qmp_phy_cfg *cfg = qmp->cfg;
> @@ -1800,41 +1774,27 @@ static int qmp_ufs_power_on(struct phy *phy)
>   {
>   	struct qmp_ufs *qmp = phy_get_drvdata(phy);
>   	const struct qmp_phy_cfg *cfg = qmp->cfg;
> +	void __iomem *pcs = qmp->pcs;
>   	int ret;
> -	dev_vdbg(qmp->dev, "Initializing QMP phy\n");
> -
> -	if (cfg->no_pcs_sw_reset) {
> -		/*
> -		 * Get UFS reset, which is delayed until now to avoid a
> -		 * circular dependency where UFS needs its PHY, but the PHY
> -		 * needs this UFS reset.
> -		 */
> -		if (!qmp->ufs_reset) {
> -			qmp->ufs_reset =
> -				devm_reset_control_get_exclusive(qmp->dev,
> -								 "ufsphy");
> -
> -			if (IS_ERR(qmp->ufs_reset)) {
> -				ret = PTR_ERR(qmp->ufs_reset);
> -				dev_err(qmp->dev,
> -					"failed to get UFS reset: %d\n",
> -					ret);
> -
> -				qmp->ufs_reset = NULL;
> -				return ret;
> -			}
> -		}
> 
> -		ret = reset_control_assert(qmp->ufs_reset);
> -		if (ret)
> -			return ret;
> +	ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
> +	if (ret) {
> +		dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
> +		return ret;
>   	}
> 
> -	ret = qmp_ufs_com_init(qmp);
> +	ret = clk_bulk_prepare_enable(qmp->num_clks, qmp->clks);
>   	if (ret)
> -		return ret;
> +		goto err_disable_regulators;
> +
> +	qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], SW_PWRDN);
> 
>   	return 0;
> +
> +err_disable_regulators:
> +	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
> +
> +	return ret;
>   }

This change is too fuzzy, please introduce qmp_ufs_get_phy_reset()
in a patch, move qmp_ufs_com_init() inline in qmp_ufs_power_on()
in a second time, and finally move reset_control_assert() to
calibrate in a third patch (and explain why).

Thanks,
Neil

> 
>   static int qmp_ufs_phy_calibrate(struct phy *phy)
> @@ -1846,6 +1806,10 @@ static int qmp_ufs_phy_calibrate(struct phy *phy)
>   	unsigned int val;
>   	int ret;
> 
> +	ret = reset_control_assert(qmp->ufs_reset);
> +	if (ret)
> +		return ret;
> +
>   	qmp_ufs_init_registers(qmp, cfg);
> 
>   	ret = reset_control_deassert(qmp->ufs_reset);
> @@ -2088,6 +2052,34 @@ static int qmp_ufs_parse_dt(struct qmp_ufs *qmp)
>   	return 0;
>   }
> 
> +static int qmp_ufs_get_phy_reset(struct qmp_ufs *qmp)
> +{
> +	const struct qmp_phy_cfg *cfg = qmp->cfg;
> +	int ret;
> +
> +	if (!cfg->no_pcs_sw_reset)
> +		return 0;
> +
> +	/*
> +	 * Get UFS reset, which is delayed until now to avoid a
> +	 * circular dependency where UFS needs its PHY, but the PHY
> +	 * needs this UFS reset.
> +	 */
> +	if (!qmp->ufs_reset) {
> +		qmp->ufs_reset =
> +		devm_reset_control_get_exclusive(qmp->dev, "ufsphy");
> +
> +		if (IS_ERR(qmp->ufs_reset)) {
> +			ret = PTR_ERR(qmp->ufs_reset);
> +			dev_err(qmp->dev, "failed to get PHY reset: %d\n", ret);
> +			qmp->ufs_reset = NULL;
> +			return ret;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>   static int qmp_ufs_probe(struct platform_device *pdev)
>   {
>   	struct device *dev = &pdev->dev;
> @@ -2114,6 +2106,10 @@ static int qmp_ufs_probe(struct platform_device *pdev)
>   	if (ret)
>   		return ret;
> 
> +	ret = qmp_ufs_get_phy_reset(qmp);
> +	if (ret)
> +		return ret;
> +
>   	/* Check for legacy binding with child node. */
>   	np = of_get_next_available_child(dev->of_node, NULL);
>   	if (np) {
> --
> 2.48.1
> 
>
Bjorn Andersson March 18, 2025, 7:46 p.m. UTC | #2 
On Tue, Mar 18, 2025 at 08:19:41PM +0530, Nitin Rawat wrote:
> Refactor the UFS PHY reset handling to parse the reset logic only once
> during probe, instead of every resume.
> 

This looks very reasonable! But it would be preferred to see the commit
messages following the what format outlines in
https://docs.kernel.org/process/submitting-patches.html#describe-your-changes
with a clear problem description followed by a description of the
technical solution.

> Move the UFS PHY reset parsing logic from qmp_phy_power_on to
> qmp_ufs_probe to avoid unnecessary parsing during resume.

Please add ()-suffix to function names in your commit messages.

Also, this series moves things around a lot, can you confirm that UFS is
working inbetween each one of this patches, so that the branch is
bisectable when this is being picked up?

> 
> Co-developed-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com>
> Signed-off-by: Ram Kumar Dwivedi <quic_rdwivedi@quicinc.com>
> Signed-off-by: Nitin Rawat <quic_nitirawa@quicinc.com>
> ---
>  drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 104 ++++++++++++------------
>  1 file changed, 50 insertions(+), 54 deletions(-)
> 
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> index 0089ee80f852..3a80c2c110d2 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> @@ -1757,32 +1757,6 @@ static void qmp_ufs_init_registers(struct qmp_ufs *qmp, const struct qmp_phy_cfg
>  	qmp_ufs_init_all(qmp, &cfg->tbls_hs_b);
>  }
> 
> -static int qmp_ufs_com_init(struct qmp_ufs *qmp)
> -{
> -	const struct qmp_phy_cfg *cfg = qmp->cfg;
> -	void __iomem *pcs = qmp->pcs;
> -	int ret;
> -
> -	ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
> -	if (ret) {
> -		dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
> -		return ret;
> -	}
> -
> -	ret = clk_bulk_prepare_enable(qmp->num_clks, qmp->clks);
> -	if (ret)
> -		goto err_disable_regulators;
> -
> -	qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], SW_PWRDN);
> -
> -	return 0;
> -
> -err_disable_regulators:
> -	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
> -
> -	return ret;
> -}
> -
>  static int qmp_ufs_com_exit(struct qmp_ufs *qmp)
>  {
>  	const struct qmp_phy_cfg *cfg = qmp->cfg;
> @@ -1800,41 +1774,27 @@ static int qmp_ufs_power_on(struct phy *phy)
>  {
>  	struct qmp_ufs *qmp = phy_get_drvdata(phy);
>  	const struct qmp_phy_cfg *cfg = qmp->cfg;
> +	void __iomem *pcs = qmp->pcs;

This is only used once, perhaps not worth a local variable to save 5
characters on that line?

>  	int ret;
> -	dev_vdbg(qmp->dev, "Initializing QMP phy\n");
> -
> -	if (cfg->no_pcs_sw_reset) {
> -		/*
> -		 * Get UFS reset, which is delayed until now to avoid a
> -		 * circular dependency where UFS needs its PHY, but the PHY
> -		 * needs this UFS reset.
> -		 */
> -		if (!qmp->ufs_reset) {
> -			qmp->ufs_reset =
> -				devm_reset_control_get_exclusive(qmp->dev,
> -								 "ufsphy");
> -
> -			if (IS_ERR(qmp->ufs_reset)) {
> -				ret = PTR_ERR(qmp->ufs_reset);
> -				dev_err(qmp->dev,
> -					"failed to get UFS reset: %d\n",
> -					ret);
> -
> -				qmp->ufs_reset = NULL;
> -				return ret;
> -			}
> -		}
> 
> -		ret = reset_control_assert(qmp->ufs_reset);
> -		if (ret)
> -			return ret;
> +	ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
> +	if (ret) {
> +		dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);

regulator_bulk_enable() will already have printed a more useful error
message, letting you know which of the vregs[] it was that failed to
enable.

> +		return ret;
>  	}
> 
> -	ret = qmp_ufs_com_init(qmp);
> +	ret = clk_bulk_prepare_enable(qmp->num_clks, qmp->clks);
>  	if (ret)
> -		return ret;
> +		goto err_disable_regulators;
> +
> +	qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], SW_PWRDN);
> 
>  	return 0;
> +
> +err_disable_regulators:
> +	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
> +
> +	return ret;
>  }
> 
>  static int qmp_ufs_phy_calibrate(struct phy *phy)
> @@ -1846,6 +1806,10 @@ static int qmp_ufs_phy_calibrate(struct phy *phy)
>  	unsigned int val;
>  	int ret;
> 
> +	ret = reset_control_assert(qmp->ufs_reset);
> +	if (ret)
> +		return ret;
> +
>  	qmp_ufs_init_registers(qmp, cfg);
> 
>  	ret = reset_control_deassert(qmp->ufs_reset);
> @@ -2088,6 +2052,34 @@ static int qmp_ufs_parse_dt(struct qmp_ufs *qmp)
>  	return 0;
>  }
> 
> +static int qmp_ufs_get_phy_reset(struct qmp_ufs *qmp)
> +{
> +	const struct qmp_phy_cfg *cfg = qmp->cfg;
> +	int ret;
> +
> +	if (!cfg->no_pcs_sw_reset)
> +		return 0;
> +
> +	/*
> +	 * Get UFS reset, which is delayed until now to avoid a
> +	 * circular dependency where UFS needs its PHY, but the PHY
> +	 * needs this UFS reset.

This is invoked only once, from qcom_ufs_probe(), so it doesn't seem
accurate anymore. How come this is no longer needed? Please describe
what changed int he commit message.

> +	 */
> +	if (!qmp->ufs_reset) {
> +		qmp->ufs_reset =
> +		devm_reset_control_get_exclusive(qmp->dev, "ufsphy");

The line break here is really weird, are you sure checkpatch --strict
didn't complain about this one?

> +
> +		if (IS_ERR(qmp->ufs_reset)) {
> +			ret = PTR_ERR(qmp->ufs_reset);
> +			dev_err(qmp->dev, "failed to get PHY reset: %d\n", ret);

return dev_err_probe(qmp->dev, PTR_ERR(qmp->ufs_reset), "failed to...: %pe\n", qmp->ufs_reset);

While being more succinct, it also stores the reason for failing the
probe so that you can find it in /sys/kernel/debug/devices_deferred

> +			qmp->ufs_reset = NULL;

Use a local variable if you're worried about someone accessing the stale
error code after returning here.

Regards,
Bjorn

> +			return ret;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  static int qmp_ufs_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
> @@ -2114,6 +2106,10 @@ static int qmp_ufs_probe(struct platform_device *pdev)
>  	if (ret)
>  		return ret;
> 
> +	ret = qmp_ufs_get_phy_reset(qmp);
> +	if (ret)
> +		return ret;
> +
>  	/* Check for legacy binding with child node. */
>  	np = of_get_next_available_child(dev->of_node, NULL);
>  	if (np) {
> --
> 2.48.1
> 
>
diff mbox series

Patch

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
index 0089ee80f852..3a80c2c110d2 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
@@ -1757,32 +1757,6 @@  static void qmp_ufs_init_registers(struct qmp_ufs *qmp, const struct qmp_phy_cfg
 	qmp_ufs_init_all(qmp, &cfg->tbls_hs_b);
 }

-static int qmp_ufs_com_init(struct qmp_ufs *qmp)
-{
-	const struct qmp_phy_cfg *cfg = qmp->cfg;
-	void __iomem *pcs = qmp->pcs;
-	int ret;
-
-	ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
-	if (ret) {
-		dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
-		return ret;
-	}
-
-	ret = clk_bulk_prepare_enable(qmp->num_clks, qmp->clks);
-	if (ret)
-		goto err_disable_regulators;
-
-	qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], SW_PWRDN);
-
-	return 0;
-
-err_disable_regulators:
-	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
-
-	return ret;
-}
-
 static int qmp_ufs_com_exit(struct qmp_ufs *qmp)
 {
 	const struct qmp_phy_cfg *cfg = qmp->cfg;
@@ -1800,41 +1774,27 @@  static int qmp_ufs_power_on(struct phy *phy)
 {
 	struct qmp_ufs *qmp = phy_get_drvdata(phy);
 	const struct qmp_phy_cfg *cfg = qmp->cfg;
+	void __iomem *pcs = qmp->pcs;
 	int ret;
-	dev_vdbg(qmp->dev, "Initializing QMP phy\n");
-
-	if (cfg->no_pcs_sw_reset) {
-		/*
-		 * Get UFS reset, which is delayed until now to avoid a
-		 * circular dependency where UFS needs its PHY, but the PHY
-		 * needs this UFS reset.
-		 */
-		if (!qmp->ufs_reset) {
-			qmp->ufs_reset =
-				devm_reset_control_get_exclusive(qmp->dev,
-								 "ufsphy");
-
-			if (IS_ERR(qmp->ufs_reset)) {
-				ret = PTR_ERR(qmp->ufs_reset);
-				dev_err(qmp->dev,
-					"failed to get UFS reset: %d\n",
-					ret);
-
-				qmp->ufs_reset = NULL;
-				return ret;
-			}
-		}

-		ret = reset_control_assert(qmp->ufs_reset);
-		if (ret)
-			return ret;
+	ret = regulator_bulk_enable(cfg->num_vregs, qmp->vregs);
+	if (ret) {
+		dev_err(qmp->dev, "failed to enable regulators, err=%d\n", ret);
+		return ret;
 	}

-	ret = qmp_ufs_com_init(qmp);
+	ret = clk_bulk_prepare_enable(qmp->num_clks, qmp->clks);
 	if (ret)
-		return ret;
+		goto err_disable_regulators;
+
+	qphy_setbits(pcs, cfg->regs[QPHY_PCS_POWER_DOWN_CONTROL], SW_PWRDN);

 	return 0;
+
+err_disable_regulators:
+	regulator_bulk_disable(cfg->num_vregs, qmp->vregs);
+
+	return ret;
 }

 static int qmp_ufs_phy_calibrate(struct phy *phy)
@@ -1846,6 +1806,10 @@  static int qmp_ufs_phy_calibrate(struct phy *phy)
 	unsigned int val;
 	int ret;

+	ret = reset_control_assert(qmp->ufs_reset);
+	if (ret)
+		return ret;
+
 	qmp_ufs_init_registers(qmp, cfg);

 	ret = reset_control_deassert(qmp->ufs_reset);
@@ -2088,6 +2052,34 @@  static int qmp_ufs_parse_dt(struct qmp_ufs *qmp)
 	return 0;
 }

+static int qmp_ufs_get_phy_reset(struct qmp_ufs *qmp)
+{
+	const struct qmp_phy_cfg *cfg = qmp->cfg;
+	int ret;
+
+	if (!cfg->no_pcs_sw_reset)
+		return 0;
+
+	/*
+	 * Get UFS reset, which is delayed until now to avoid a
+	 * circular dependency where UFS needs its PHY, but the PHY
+	 * needs this UFS reset.
+	 */
+	if (!qmp->ufs_reset) {
+		qmp->ufs_reset =
+		devm_reset_control_get_exclusive(qmp->dev, "ufsphy");
+
+		if (IS_ERR(qmp->ufs_reset)) {
+			ret = PTR_ERR(qmp->ufs_reset);
+			dev_err(qmp->dev, "failed to get PHY reset: %d\n", ret);
+			qmp->ufs_reset = NULL;
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
 static int qmp_ufs_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -2114,6 +2106,10 @@  static int qmp_ufs_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;

+	ret = qmp_ufs_get_phy_reset(qmp);
+	if (ret)
+		return ret;
+
 	/* Check for legacy binding with child node. */
 	np = of_get_next_available_child(dev->of_node, NULL);
 	if (np) {