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> Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> --- Changelog: v4: Added Acked-by v3: move requesting of PHY2 region to right where we need it v2: don't add phy read/write helpers or add phy to private data v1: https://lore.kernel.org/all/20240201121220.5523-5-rogerq@xxxxxxxxxx/ --- drivers/usb/dwc3/dwc3-am62.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/dwc3-am62.c b/drivers/usb/dwc3/dwc3-am62.c index 09b1f5a1c4fb..fad151e78fd6 100644 --- a/drivers/usb/dwc3/dwc3-am62.c +++ b/drivers/usb/dwc3/dwc3-am62.c @@ -101,6 +101,11 @@ #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 { @@ -184,8 +189,9 @@ 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; - int i, ret; unsigned long rate; + void __iomem *phy; + int i, ret; u32 reg; am62 = devm_kzalloc(dev, sizeof(*am62), GFP_KERNEL); @@ -227,6 +233,17 @@ static int dwc3_ti_probe(struct platform_device *pdev) if (ret) return ret; + /* Workaround Errata i2409 */ + phy = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(phy)) { + 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); + } + /* 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
