Commit b138e23d authored by Anurag Kumar Vulisha's avatar Anurag Kumar Vulisha Committed by Felipe Balbi
Browse files

usb: dwc3: core: 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.

Signed-off-by: default avatarAnurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>
Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
parent a7700468

drivers/usb/dwc3/core.c

+16 −0
Original line number Diff line number Diff line
@@ -985,6 +985,22 @@ static int dwc3_core_init(struct dwc3 *dwc) 
		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);



		/*

		 * Enable Auto retry Feature to make the controller operating in

		 * Host mode on seeing transaction errors(CRC errors or internal

		 * overrun scenerios) on IN transfers to reply to the device

		 * with a non-terminating retry ACK (i.e, an ACK transcation

		 * packet with Retry=1 & Nump != 0)

		 */

		reg |= DWC3_GUCTL_HSTINAUTORETRY;



		dwc3_writel(dwc->regs, DWC3_GUCTL, reg);

	}



	/*

	 * Must config both number of packets and max burst settings to enable

	 * RX and/or TX threshold.

drivers/usb/dwc3/core.h

+3 −0
Original line number Diff line number Diff line
@@ -238,6 +238,9 @@ 
#define DWC3_GCTL_GBLHIBERNATIONEN	BIT(1)

#define DWC3_GCTL_DSBLCLKGTNG		BIT(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)

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