Re: [PATCH] usb: dwc2: update reset method for host and device mode

On 4/22/24 7:31 AM, Kongyang Liu wrote:

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@@ -167,9 +168,20 @@ static void dwc_otg_core_reset(struct udevice *dev, dev_info(dev, "%s: Timeout!\n", __func__);

   /* Core Soft Reset */

• snpsid = readl(&regs->gsnpsid);
   writel(DWC2_GRSTCTL_CSFTRST, &regs->grstctl);
  

• ret = wait_for_bit_le32(&regs->grstctl, DWC2_GRSTCTL_CSFTRST,
  

•                         false, 1000, false);
  

• if ((snpsid & DWC2_SNPSID_VER_MASK) < (DWC2_SNPSID_DEVID_VER_420a & DWC2_SNPSID_VER_MASK)) {
  

•         ret = wait_for_bit_le32(&regs->grstctl, DWC2_GRSTCTL_CSFTRST,
  

•                                 false, 1000, false);
  

• } else {
  

•         ret = wait_for_bit_le32(&regs->grstctl, DWC2_GRSTCTL_GSFTRST_DONE,
  

•                                 true, 1000, false);
  

•         greset = readl(&regs->grstctl);
  

•         greset &= ~DWC2_GRSTCTL_CSFTRST;
  

•         greset |= DWC2_GRSTCTL_GSFTRST_DONE;
  

•         writel(greset, &regs->grstctl);
  

Same comments as above.

Maybe this should be pulled into dedicated function to avoid duplication?

For U-Boot, the dwc2 USB driver is split into two modules: host and gadget. Each has its own register definitions and definitions for register bits, which makes it difficult to extract a single function. Moreover, deciding where to place this function is also an issue.

There is drivers/usb/common/ for such code. The register macros can probably be unified into a single header too.