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

[Marek Vasut]

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

[...]

>>> @@ -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.