RE: [PATCH v2 1/2] usb: dwc3: core: add support for remapping global register start address

Stanley Chang[昌育德]
2023-04-13T03:44:49Z

> > > + /*
> > > + * For some dwc3 controller, the dwc3 global register start address
> is
> > > + * not at DWC3_GLOBALS_REGS_START (0xc100).
> > > + */
> > > + if (dev->of_node) {
> > > + int global_regs_starting_offset = 0;
> > > +
> > > + device_property_read_u32(dev,
> > "snps,global-regs-starting-offset",
> > > + &global_regs_starting_offset);
> >
> > I suggested to use compatible string instead since this isn't common
> > and only unique to your platform. Any reason we shouldn't do that?
> >
> > ie. something like this:
> >
> > if (dev->of_node && of_device_is_compatiable(dev->of_node,
> > "your-platform"))
> > dwc_res.start += your_platform_offset; else
> > dwc_res.start = DWC3_GLOBALS_REGS_START;
> >
>
> I will try this suggestion.
>
> Thanks,
> Stanley

The dwc3/core is a general driver for every dwc3 IP of SoCs,
and vendor's definition and compatible should specify on its parent.
This should be inappropriate if we add a special platform compatible to dwc3/core driver.
Therefore, I define this property to adjust this value. This is more resilient.
If there are other platforms that also have non-standard offset, this property is also applicable.

Thank,
Stanley