If controller looses power during PM suspend then re-initialize it. We use the DEBUG_CFG register to track if controller lost power or was reset in PM suspend. Move all initialization code into dwc3_ti_init() so it can be re-used. Signed-off-by: Roger Quadros <rogerq@xxxxxxxxxx> Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> --- Changes in v3: - renamed member phy to phy_regs as it is PHY register space - Added Acked-by from Thinh Nguyen - Link to v2: https://lore.kernel.org/r/20241209-am62-dwc3-io-ddr-v2-1-da320392b509@xxxxxxxxxx Changes in v2: - fixed macro USBSS_DEBUG_CFG_OFF to 0 - Link to v1: https://lore.kernel.org/r/20241122-am62-dwc3-io-ddr-v1-1-cc4956449420@xxxxxxxxxx --- drivers/usb/dwc3/dwc3-am62.c | 82 +++++++++++++++++++++++++++++--------------- 1 file changed, 55 insertions(+), 27 deletions(-) diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c index 5e3d1741701f..a740d3d70e87 100644 --- a/drivers/usb/dwc3/dwc3-am62.c +++ b/drivers/usb/dwc3/dwc3-am62.c @@ -108,6 +108,9 @@ #define DWC3_AM62_AUTOSUSPEND_DELAY 100 +#define USBSS_DEBUG_CFG_OFF 0x0 +#define USBSS_DEBUG_CFG_DISABLED 0x7 + struct dwc3_am62 { struct device *dev; void __iomem *usbss; @@ -117,6 +120,7 @@ struct dwc3_am62 { unsigned int offset; unsigned int vbus_divider; u32 wakeup_stat; + void __iomem *phy_regs; }; static const int dwc3_ti_rate_table[] = { /* in KHZ */ @@ -184,15 +188,47 @@ static int phy_syscon_pll_refclk(struct dwc3_am62 *am62) return 0; } +static int dwc3_ti_init(struct dwc3_am62 *am62) +{ + int ret; + u32 reg; + + /* Read the syscon property and set the rate code */ + ret = phy_syscon_pll_refclk(am62); + if (ret) + return ret; + + /* Workaround Errata i2409 */ + if (am62->phy_regs) { + reg = readl(am62->phy_regs + USB_PHY_PLL_REG12); + reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN; + writel(reg, am62->phy_regs + USB_PHY_PLL_REG12); + } + + /* VBUS divider select */ + reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG); + if (am62->vbus_divider) + reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT; + + dwc3_ti_writel(am62, USBSS_PHY_CONFIG, reg); + + clk_prepare_enable(am62->usb2_refclk); + + /* Set mode valid bit to indicate role is valid */ + reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL); + reg |= USBSS_MODE_VALID; + dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg); + + return 0; +} + static int dwc3_ti_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *node = pdev->dev.of_node; struct dwc3_am62 *am62; unsigned long rate; - void __iomem *phy; int i, ret; - u32 reg; am62 = devm_kzalloc(dev, sizeof(*am62), GFP_KERNEL); if (!am62) @@ -228,29 +264,17 @@ static int dwc3_ti_probe(struct platform_device *pdev) am62->rate_code = i; - /* Read the syscon property and set the rate code */ - ret = phy_syscon_pll_refclk(am62); - if (ret) - return ret; - - /* Workaround Errata i2409 */ - phy = devm_platform_ioremap_resource(pdev, 1); - if (IS_ERR(phy)) { + am62->phy_regs = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(am62->phy_regs)) { dev_err(dev, "can't map PHY IOMEM resource. Won't apply i2409 fix.\n"); - phy = NULL; - } else { - reg = readl(phy + USB_PHY_PLL_REG12); - reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN; - writel(reg, phy + USB_PHY_PLL_REG12); + am62->phy_regs = NULL; } - /* VBUS divider select */ am62->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider"); - reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG); - if (am62->vbus_divider) - reg |= 1 << USBSS_PHY_VBUS_SEL_SHIFT; - dwc3_ti_writel(am62, USBSS_PHY_CONFIG, reg); + ret = dwc3_ti_init(am62); + if (ret) + return ret; pm_runtime_set_active(dev); pm_runtime_enable(dev); @@ -258,7 +282,6 @@ static int dwc3_ti_probe(struct platform_device *pdev) * Don't ignore its dependencies with its children */ pm_suspend_ignore_children(dev, false); - clk_prepare_enable(am62->usb2_refclk); pm_runtime_get_noresume(dev); ret = of_platform_populate(node, NULL, NULL, dev); @@ -267,11 +290,6 @@ static int dwc3_ti_probe(struct platform_device *pdev) goto err_pm_disable; } - /* Set mode valid bit to indicate role is valid */ - reg = dwc3_ti_readl(am62, USBSS_MODE_CONTROL); - reg |= USBSS_MODE_VALID; - dwc3_ti_writel(am62, USBSS_MODE_CONTROL, reg); - /* Device has capability to wakeup system from sleep */ device_set_wakeup_capable(dev, true); ret = device_wakeup_enable(dev); @@ -338,6 +356,9 @@ static int dwc3_ti_suspend_common(struct device *dev) dwc3_ti_writel(am62, USBSS_WAKEUP_STAT, USBSS_WAKEUP_STAT_CLR); } + /* just to track if module resets on suspend */ + dwc3_ti_writel(am62, USBSS_DEBUG_CFG, USBSS_DEBUG_CFG_DISABLED); + clk_disable_unprepare(am62->usb2_refclk); return 0; @@ -348,7 +369,14 @@ static int dwc3_ti_resume_common(struct device *dev) struct dwc3_am62 *am62 = dev_get_drvdata(dev); u32 reg; - clk_prepare_enable(am62->usb2_refclk); + reg = dwc3_ti_readl(am62, USBSS_DEBUG_CFG); + if (reg != USBSS_DEBUG_CFG_DISABLED) { + /* lost power/context */ + dwc3_ti_init(am62); + } else { + dwc3_ti_writel(am62, USBSS_DEBUG_CFG, USBSS_DEBUG_CFG_OFF); + clk_prepare_enable(am62->usb2_refclk); + } if (device_may_wakeup(dev)) { /* Clear wakeup config enable bits */ --- base-commit: cdd30ebb1b9f36159d66f088b61aee264e649d7a change-id: 20241122-am62-dwc3-io-ddr-3bcb683a91a0 Best regards, -- Roger Quadros <rogerq@xxxxxxxxxx>