usb: dwc3: Enable AutoRetry feature in the controller
By default when core sees any transaction error (CRC or overflow) it
replies with terminating retry ACK (Retry=1 and Nump == 0).
Enabling this Auto Retry feature in controller will make the core send
a non-terminanting ACK upon such transaction errors. That is, ACK TP
with Retry=1 and Nump != 0.
Doing so will give controller a chance to recover from transient error
conditions.
Reference from below Linux commit,
commit <b138e23d3dff> ("usb: dwc3: core: Enable AutoRetry feature
in the controller")
Cc: Marek Vasut <marex@denx.de>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index b399c9b..d7f666b 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -997,6 +997,15 @@
dwc3_writel(dwc->regs, DWC3_GUCTL1, reg);
}
+ if (dwc->dr_mode == USB_DR_MODE_HOST ||
+ dwc->dr_mode == USB_DR_MODE_OTG) {
+ reg = dwc3_readl(dwc->regs, DWC3_GUCTL);
+
+ reg |= DWC3_GUCTL_HSTINAUTORETRY;
+
+ dwc3_writel(dwc->regs, DWC3_GUCTL, reg);
+ }
+
ret = dwc3_core_init_mode(dwc);
if (ret)
goto mode_fail;
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index ca72b49..d1f8606 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -161,6 +161,9 @@
#define DWC3_GCTL_GBLHIBERNATIONEN (1 << 1)
#define DWC3_GCTL_DSBLCLKGTNG (1 << 0)
+/* Global User Control Register */
+#define DWC3_GUCTL_HSTINAUTORETRY BIT(14)
+
/* Global User Control 1 Register */
#define DWC3_GUCTL1_TX_IPGAP_LINECHECK_DIS BIT(28)
#define DWC3_GUCTL1_DEV_L1_EXIT_BY_HW BIT(24)