On Fri, Nov 22, 2024, Roger Quadros wrote:
> 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>
> ---
> 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 fad151e78fd6..2192222faf4f 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 0x7
> +#define USBSS_DEBUG_CFG_DISABLED 0x7
Do we need 2 different macros with the same value of the same register
for this?
Regardless,
Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
Thanks,
Thinh
> +
> 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;
> };
>
> 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) {
> + reg = readl(am62->phy + USB_PHY_PLL_REG12);
> + reg |= USB_PHY_PLL_LDO_REF_EN | USB_PHY_PLL_LDO_REF_EN_EN;
> + writel(reg, am62->phy + 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 = 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");
> - 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 = 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: adc218676eef25575469234709c2d87185ca223a
> change-id: 20241122-am62-dwc3-io-ddr-3bcb683a91a0
>
> Best regards,
> --
> Roger Quadros <rogerq@xxxxxxxxxx>
>
