All AM62 devices have Errata i2409 [1] due to which USB2 PHY may lock up due to short suspend. Workaround involves setting bit 5 and 4 PLL_REG12 in PHY2 register space after USB controller is brought out of LPSC reset but before controller initialization. Handle this workaround. [1] - https://www.ti.com/lit/er/sprz487d/sprz487d.pdf Signed-off-by: Roger Quadros <rogerq@xxxxxxxxxx> --- drivers/usb/dwc3/dwc3-am62.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c index af1ce934e7fb..35d7a2fb128e 100644 --- a/drivers/usb/dwc3/dwc3-am62.c +++ b/drivers/usb/dwc3/dwc3-am62.c @@ -101,11 +101,17 @@ #define PHY_CORE_VOLTAGE_MASK BIT(31) #define PHY_PLL_REFCLK_MASK GENMASK(3, 0) +/* USB PHY2 register offsets */ +#define USB_PHY_PLL_REG12 0x130 +#define USB_PHY_PLL_LDO_REF_EN BIT(5) +#define USB_PHY_PLL_LDO_REF_EN_EN BIT(4) + #define DWC3_AM62_AUTOSUSPEND_DELAY 100 struct dwc3_am62 { struct device *dev; void __iomem *usbss; + void __iomem *phy; struct clk *usb2_refclk; int rate_code; struct regmap *syscon; @@ -140,6 +146,16 @@ static inline void dwc3_ti_writel(struct dwc3_am62 *am62, u32 offset, u32 value) writel(value, (am62->usbss) + offset); } +static inline u32 dwc3_ti_phy_readl(struct dwc3_am62 *am62, u32 offset) +{ + return readl((am62->phy) + offset); +} + +static inline void dwc3_ti_phy_writel(struct dwc3_am62 *am62, u32 offset, u32 value) +{ + writel(value, (am62->phy) + offset); +} + static int phy_syscon_pll_refclk(struct dwc3_am62 *am62) { struct device *dev = am62->dev; @@ -201,6 +217,12 @@ static int dwc3_ti_probe(struct platform_device *pdev) return PTR_ERR(am62->usbss); } + am62->phy = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(am62->phy)) { + dev_err(dev, "can't map PHY IOMEM resource. Won't apply i2409 fix.\n"); + am62->phy = NULL; + } + am62->usb2_refclk = devm_clk_get(dev, "ref"); if (IS_ERR(am62->usb2_refclk)) { dev_err(dev, "can't get usb2_refclk\n"); @@ -227,6 +249,13 @@ static int dwc3_ti_probe(struct platform_device *pdev) if (ret) return ret; + /* Workaround Errata i2409 */ + if (am62->phy) { + reg = dwc3_ti_phy_readl(am62, USB_PHY_PLL_REG12); + reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN; + dwc3_ti_phy_writel(am62, USB_PHY_PLL_REG12, reg); + } + /* VBUS divider select */ am62->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider"); reg = dwc3_ti_readl(am62, USBSS_PHY_CONFIG); -- 2.34.1
