Commit 25d70083 authored by Piyush Mehta's avatar Piyush Mehta Committed by Vinod Koul
Browse files

phy: xilinx: phy-zynqmp: dynamic clock support for power-save 



Enabling clock for all the lanes consumes power even PHY is active or
inactive. To resolve this, enable/disable clocks in phy_init/phy_exit.

By default clock is disabled for all the lanes. Whenever phy_init called
from USB, SATA, or display driver, etc. It enabled the required clock
for requested lane. On phy_exit cycle, it disabled clock for the active
PHYs.

During the suspend/resume cycle, each USB/ SATA/ display driver called
phy_exit/phy_init individually. It disabled clock on exit, and enabled
on initialization for the active PHYs.

Signed-off-by: default avatarPiyush Mehta <piyush.mehta@amd.com>
Link: https://lore.kernel.org/r/20230613140250.3018947-3-piyush.mehta@amd.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent b3db66f6

drivers/phy/xilinx/phy-zynqmp.c

+15 −46
Original line number Diff line number Diff line
@@ -572,6 +572,10 @@ static int xpsgtr_phy_init(struct phy *phy) 


	mutex_lock(&gtr_dev->gtr_mutex);



	/* Configure and enable the clock when peripheral phy_init call */

	if (clk_prepare_enable(gtr_dev->clk[gtr_phy->lane]))

		goto out;



	/* Skip initialization if not required. */

	if (!xpsgtr_phy_init_required(gtr_phy))

		goto out;
@@ -616,9 +620,13 @@ static int xpsgtr_phy_init(struct phy *phy) 
static int xpsgtr_phy_exit(struct phy *phy)

{

	struct xpsgtr_phy *gtr_phy = phy_get_drvdata(phy);

	struct xpsgtr_dev *gtr_dev = gtr_phy->dev;



	gtr_phy->skip_phy_init = false;



	/* Ensure that disable clock only, which configure for lane */

	clk_disable_unprepare(gtr_dev->clk[gtr_phy->lane]);



	return 0;

}
@@ -824,15 +832,11 @@ static struct phy *xpsgtr_xlate(struct device *dev, 
static int xpsgtr_runtime_suspend(struct device *dev)

{

	struct xpsgtr_dev *gtr_dev = dev_get_drvdata(dev);

	unsigned int i;



	/* Save the snapshot ICM_CFG registers. */

	gtr_dev->saved_icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0);

	gtr_dev->saved_icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1);



	for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++)

		clk_disable_unprepare(gtr_dev->clk[i]);



	return 0;

}
@@ -842,13 +846,6 @@ static int xpsgtr_runtime_resume(struct device *dev) 
	unsigned int icm_cfg0, icm_cfg1;

	unsigned int i;

	bool skip_phy_init;

	int err;



	for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++) {

		err = clk_prepare_enable(gtr_dev->clk[i]);

		if (err)

			goto err_clk_put;

	}



	icm_cfg0 = xpsgtr_read(gtr_dev, ICM_CFG0);

	icm_cfg1 = xpsgtr_read(gtr_dev, ICM_CFG1);
@@ -869,12 +866,6 @@ static int xpsgtr_runtime_resume(struct device *dev) 
		gtr_dev->phys[i].skip_phy_init = skip_phy_init;



	return 0;



err_clk_put:

	while (i--)

		clk_disable_unprepare(gtr_dev->clk[i]);



	return err;

}



static DEFINE_RUNTIME_DEV_PM_OPS(xpsgtr_pm_ops, xpsgtr_runtime_suspend,
@@ -886,7 +877,6 @@ static DEFINE_RUNTIME_DEV_PM_OPS(xpsgtr_pm_ops, xpsgtr_runtime_suspend, 
static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev)

{

	unsigned int refclk;

	int ret;



	for (refclk = 0; refclk < ARRAY_SIZE(gtr_dev->refclk_sscs); ++refclk) {

		unsigned long rate;
@@ -897,19 +887,14 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) 
		snprintf(name, sizeof(name), "ref%u", refclk);

		clk = devm_clk_get_optional(gtr_dev->dev, name);

		if (IS_ERR(clk)) {

			ret = dev_err_probe(gtr_dev->dev, PTR_ERR(clk),

					    "Failed to get reference clock %u\n",

			return dev_err_probe(gtr_dev->dev, PTR_ERR(clk),

					     "Failed to get ref clock %u\n",

					     refclk);

			goto err_clk_put;

		}



		if (!clk)

			continue;



		ret = clk_prepare_enable(clk);

		if (ret)

			goto err_clk_put;



		gtr_dev->clk[refclk] = clk;



		/*
@@ -929,18 +914,11 @@ static int xpsgtr_get_ref_clocks(struct xpsgtr_dev *gtr_dev) 
			dev_err(gtr_dev->dev,

				"Invalid rate %lu for reference clock %u\n",

				rate, refclk);

			ret = -EINVAL;

			goto err_clk_put;

			return -EINVAL;

		}

	}



	return 0;



err_clk_put:

	while (refclk--)

		clk_disable_unprepare(gtr_dev->clk[refclk]);



	return ret;

}



static int xpsgtr_probe(struct platform_device *pdev)
@@ -949,7 +927,6 @@ static int xpsgtr_probe(struct platform_device *pdev) 
	struct xpsgtr_dev *gtr_dev;

	struct phy_provider *provider;

	unsigned int port;

	unsigned int i;

	int ret;



	gtr_dev = devm_kzalloc(&pdev->dev, sizeof(*gtr_dev), GFP_KERNEL);
@@ -989,8 +966,7 @@ static int xpsgtr_probe(struct platform_device *pdev) 
		phy = devm_phy_create(&pdev->dev, np, &xpsgtr_phyops);

		if (IS_ERR(phy)) {

			dev_err(&pdev->dev, "failed to create PHY\n");

			ret = PTR_ERR(phy);

			goto err_clk_put;

			return PTR_ERR(phy);

		}



		gtr_phy->phy = phy;
@@ -1001,8 +977,7 @@ static int xpsgtr_probe(struct platform_device *pdev) 
	provider = devm_of_phy_provider_register(&pdev->dev, xpsgtr_xlate);

	if (IS_ERR(provider)) {

		dev_err(&pdev->dev, "registering provider failed\n");

		ret = PTR_ERR(provider);

		goto err_clk_put;

		return PTR_ERR(provider);

	}



	pm_runtime_set_active(gtr_dev->dev);
@@ -1011,16 +986,10 @@ static int xpsgtr_probe(struct platform_device *pdev) 
	ret = pm_runtime_resume_and_get(gtr_dev->dev);

	if (ret < 0) {

		pm_runtime_disable(gtr_dev->dev);

		goto err_clk_put;

		return ret;

	}



	return 0;



err_clk_put:

	for (i = 0; i < ARRAY_SIZE(gtr_dev->clk); i++)

		clk_disable_unprepare(gtr_dev->clk[i]);



	return ret;

}



static int xpsgtr_remove(struct platform_device *pdev)