RE: [PATCH v5 3/9] usb: cdns3: imx: add glue layer runtime pm implementation

[Pawel Laszczak <pawell@cadence.com>]

>
>Add imx glue layer runtime pm implementation, and the runtime
>pm is default off.
>
>Signed-off-by: Peter Chen <peter.chen@nxp.com>

Reviewed-by: Pawel Laszczak <pawell@cadence.com>

>---
> drivers/usb/cdns3/cdns3-imx.c | 203 ++++++++++++++++++++++++++++++++--
> 1 file changed, 192 insertions(+), 11 deletions(-)
>
>diff --git a/drivers/usb/cdns3/cdns3-imx.c b/drivers/usb/cdns3/cdns3-imx.c
>index aba988e71958..5d2a4e19fa83 100644
>--- a/drivers/usb/cdns3/cdns3-imx.c
>+++ b/drivers/usb/cdns3/cdns3-imx.c
>@@ -15,6 +15,8 @@
> #include <linux/io.h>
> #include <linux/of_platform.h>
> #include <linux/iopoll.h>
>+#include <linux/pm_runtime.h>
>+#include "core.h"
>
> #define USB3_CORE_CTRL1    0x00
> #define USB3_CORE_CTRL2    0x04
>@@ -32,7 +34,7 @@
> /* Register bits definition */
>
> /* USB3_CORE_CTRL1 */
>-#define SW_RESET_MASK	(0x3f << 26)
>+#define SW_RESET_MASK	GENMASK(31, 26)
> #define PWR_SW_RESET	BIT(31)
> #define APB_SW_RESET	BIT(30)
> #define AXI_SW_RESET	BIT(29)
>@@ -44,17 +46,17 @@
> #define OC_DISABLE	BIT(9)
> #define MDCTRL_CLK_SEL	BIT(7)
> #define MODE_STRAP_MASK	(0x7)
>-#define DEV_MODE	(1 << 2)
>-#define HOST_MODE	(1 << 1)
>-#define OTG_MODE	(1 << 0)
>+#define DEV_MODE	BIT(2)
>+#define HOST_MODE	BIT(1)
>+#define OTG_MODE	BIT(0)
>
> /* USB3_INT_REG */
> #define CLK_125_REQ	BIT(29)
> #define LPM_CLK_REQ	BIT(28)
> #define DEVU3_WAEKUP_EN	BIT(14)
> #define OTG_WAKEUP_EN	BIT(12)
>-#define DEV_INT_EN (3 << 8) /* DEV INT b9:8 */
>-#define HOST_INT1_EN (1 << 0) /* HOST INT b7:0 */
>+#define DEV_INT_EN	GENMASK(9, 8) /* DEV INT b9:8 */
>+#define HOST_INT1_EN	BIT(0) /* HOST INT b7:0 */
>
> /* USB3_CORE_STATUS */
> #define MDCTRL_CLK_STATUS	BIT(15)
>@@ -62,15 +64,34 @@
> #define HOST_POWER_ON_READY	BIT(12)
>
> /* USB3_SSPHY_STATUS */
>-#define CLK_VALID_MASK		(0x3f << 26)
>-#define CLK_VALID_COMPARE_BITS	(0xf << 28)
>-#define PHY_REFCLK_REQ		(1 << 0)
>+#define CLK_VALID_MASK		GENMASK(31, 26)
>+#define CLK_VALID_COMPARE_BITS	GENMASK(31, 28)
>+#define PHY_REFCLK_REQ		BIT(0)
>+
>+/* OTG registers definition */
>+#define OTGSTS		0x4
>+/* OTGSTS */
>+#define OTG_NRDY	BIT(11)
>+
>+/* xHCI registers definition  */
>+#define XECP_PM_PMCSR		0x8018
>+#define XECP_AUX_CTRL_REG1	0x8120
>+
>+/* Register bits definition */
>+/* XECP_AUX_CTRL_REG1 */
>+#define CFG_RXDET_P3_EN		BIT(15)
>+
>+/* XECP_PM_PMCSR */
>+#define PS_MASK			GENMASK(1, 0)
>+#define PS_D0			0
>+#define PS_D1			1
>
> struct cdns_imx {
> 	struct device *dev;
> 	void __iomem *noncore;
> 	struct clk_bulk_data *clks;
> 	int num_clks;
>+	struct platform_device *cdns3_pdev;
> };
>
> static inline u32 cdns_imx_readl(struct cdns_imx *data, u32 offset)
>@@ -126,6 +147,20 @@ static int cdns_imx_noncore_init(struct cdns_imx *data)
> 	return ret;
> }
>
>+static int cdns_imx_platform_suspend(struct device *dev,
>+	bool suspend, bool wakeup);
>+static struct cdns3_platform_data cdns_imx_pdata = {
>+	.platform_suspend = cdns_imx_platform_suspend,
>+};
>+
>+static struct of_dev_auxdata cdns_imx_auxdata[] = {
>+	{
>+	.compatible = "cdns,usb3",
>+	.platform_data = &cdns_imx_pdata,
>+	},
>+	{},
>+};
>+
> static int cdns_imx_probe(struct platform_device *pdev)
> {
> 	struct device *dev = &pdev->dev;
>@@ -162,14 +197,18 @@ static int cdns_imx_probe(struct platform_device *pdev)
> 	if (ret)
> 		goto err;
>
>-	ret = of_platform_populate(node, NULL, NULL, dev);
>+	ret = of_platform_populate(node, NULL, cdns_imx_auxdata, dev);
> 	if (ret) {
> 		dev_err(dev, "failed to create children: %d\n", ret);
> 		goto err;
> 	}
>
>-	return ret;
>+	device_set_wakeup_capable(dev, true);
>+	pm_runtime_set_active(dev);
>+	pm_runtime_enable(dev);
>+	pm_runtime_forbid(dev);
>
>+	return ret;
> err:
> 	clk_bulk_disable_unprepare(data->num_clks, data->clks);
> 	return ret;
>@@ -194,6 +233,147 @@ static int cdns_imx_remove(struct platform_device *pdev)
> 	return 0;
> }
>
>+#ifdef CONFIG_PM
>+static void cdns3_set_wakeup(struct cdns_imx *data, bool enable)
>+{
>+	u32 value;
>+
>+	value = cdns_imx_readl(data, USB3_INT_REG);
>+	if (enable)
>+		value |= OTG_WAKEUP_EN | DEVU3_WAEKUP_EN;
>+	else
>+		value &= ~(OTG_WAKEUP_EN | DEVU3_WAEKUP_EN);
>+
>+	cdns_imx_writel(data, USB3_INT_REG, value);
>+}
>+
>+static int cdns_imx_platform_suspend(struct device *dev,
>+		bool suspend, bool wakeup)
>+{
>+	struct cdns3 *cdns = dev_get_drvdata(dev);
>+	struct device *parent = dev->parent;
>+	struct cdns_imx *data = dev_get_drvdata(parent);
>+	void __iomem *otg_regs = (void *)(cdns->otg_regs);
>+	void __iomem *xhci_regs = cdns->xhci_regs;
>+	u32 value;
>+	int ret = 0;
>+
>+	if (cdns->role != USB_ROLE_HOST)
>+		return 0;
>+
>+	if (suspend) {
>+		/* SW request low power when all usb ports allow to it ??? */
>+		value = readl(xhci_regs + XECP_PM_PMCSR);
>+		value &= ~PS_MASK;
>+		value |= PS_D1;
>+		writel(value, xhci_regs + XECP_PM_PMCSR);
>+
>+		/* mdctrl_clk_sel */
>+		value = cdns_imx_readl(data, USB3_CORE_CTRL1);
>+		value |= MDCTRL_CLK_SEL;
>+		cdns_imx_writel(data, USB3_CORE_CTRL1, value);
>+
>+		/* wait for mdctrl_clk_status */
>+		value = cdns_imx_readl(data, USB3_CORE_STATUS);
>+		ret = readl_poll_timeout(data->noncore + USB3_CORE_STATUS, value,
>+			(value & MDCTRL_CLK_STATUS) == MDCTRL_CLK_STATUS,
>+			10, 100000);
>+		if (ret)
>+			dev_warn(parent, "wait mdctrl_clk_status timeout\n");
>+
>+		/* wait lpm_clk_req to be 0 */
>+		value = cdns_imx_readl(data, USB3_INT_REG);
>+		ret = readl_poll_timeout(data->noncore + USB3_INT_REG, value,
>+			(value & LPM_CLK_REQ) != LPM_CLK_REQ,
>+			10, 100000);
>+		if (ret)
>+			dev_warn(parent, "wait lpm_clk_req timeout\n");
>+
>+		/* wait phy_refclk_req to be 0 */
>+		value = cdns_imx_readl(data, USB3_SSPHY_STATUS);
>+		ret = readl_poll_timeout(data->noncore + USB3_SSPHY_STATUS, value,
>+			(value & PHY_REFCLK_REQ) != PHY_REFCLK_REQ,
>+			10, 100000);
>+		if (ret)
>+			dev_warn(parent, "wait phy_refclk_req timeout\n");
>+
>+		cdns3_set_wakeup(data, wakeup);
>+	} else {
>+		cdns3_set_wakeup(data, false);
>+
>+		/* SW request D0 */
>+		value = readl(xhci_regs + XECP_PM_PMCSR);
>+		value &= ~PS_MASK;
>+		value |= PS_D0;
>+		writel(value, xhci_regs + XECP_PM_PMCSR);
>+
>+		/* clr CFG_RXDET_P3_EN */
>+		value = readl(xhci_regs + XECP_AUX_CTRL_REG1);
>+		value &= ~CFG_RXDET_P3_EN;
>+		writel(value, xhci_regs + XECP_AUX_CTRL_REG1);
>+
>+		/* clear mdctrl_clk_sel */
>+		value = cdns_imx_readl(data, USB3_CORE_CTRL1);
>+		value &= ~MDCTRL_CLK_SEL;
>+		cdns_imx_writel(data, USB3_CORE_CTRL1, value);
>+
>+		/* wait CLK_125_REQ to be 1 */
>+		value = cdns_imx_readl(data, USB3_INT_REG);
>+		ret = readl_poll_timeout(data->noncore + USB3_INT_REG, value,
>+			(value & CLK_125_REQ) == CLK_125_REQ,
>+			10, 100000);
>+		if (ret)
>+			dev_warn(parent, "wait CLK_125_REQ timeout\n");
>+
>+		/* wait for mdctrl_clk_status is cleared */
>+		value = cdns_imx_readl(data, USB3_CORE_STATUS);
>+		ret = readl_poll_timeout(data->noncore + USB3_CORE_STATUS, value,
>+			(value & MDCTRL_CLK_STATUS) != MDCTRL_CLK_STATUS,
>+			10, 100000);
>+		if (ret)
>+			dev_warn(parent, "wait mdctrl_clk_status cleared timeout\n");
>+
>+		/* Wait until OTG_NRDY is 0 */
>+		value = readl(otg_regs + OTGSTS);
>+		ret = readl_poll_timeout(otg_regs + OTGSTS, value,
>+			(value & OTG_NRDY) != OTG_NRDY,
>+			10, 100000);
>+		if (ret)
>+			dev_warn(parent, "wait OTG ready timeout\n");
>+	}
>+
>+	return ret;
>+
>+}
>+
>+static int cdns_imx_resume(struct device *dev)
>+{
>+	struct cdns_imx *data = dev_get_drvdata(dev);
>+
>+	return clk_bulk_prepare_enable(data->num_clks, data->clks);
>+}
>+
>+static int cdns_imx_suspend(struct device *dev)
>+{
>+	struct cdns_imx *data = dev_get_drvdata(dev);
>+
>+	clk_bulk_disable_unprepare(data->num_clks, data->clks);
>+
>+	return 0;
>+}
>+#else
>+static int cdns_imx_platform_suspend(struct device *dev,
>+	bool suspend, bool wakeup)
>+{
>+	return 0;
>+}
>+
>+#endif /* CONFIG_PM */
>+
>+static const struct dev_pm_ops cdns_imx_pm_ops = {
>+	SET_RUNTIME_PM_OPS(cdns_imx_suspend, cdns_imx_resume, NULL)
>+};
>+
> static const struct of_device_id cdns_imx_of_match[] = {
> 	{ .compatible = "fsl,imx8qm-usb3", },
> 	{},
>@@ -206,6 +386,7 @@ static struct platform_driver cdns_imx_driver = {
> 	.driver		= {
> 		.name	= "cdns3-imx",
> 		.of_match_table	= cdns_imx_of_match,
>+		.pm	= &cdns_imx_pm_ops,
> 	},
> };
> module_platform_driver(cdns_imx_driver);
>--
>2.17.1