[PATCH 3/6] platform: andes: Add Andes custom PMU support

[Yu-Chien Peter Lin <peterlin@andestech.com>]

> > > +               sbi_pmu_set_device(&andes_pmu);
> > In my opinion we might want to append the PMU node to DT here
> 
> Sure, I will add fdt fixup so RZ/Five users won't need to manually
> append the PMU node.
> 
> > and pass that DT fragment to the higher stack instead of adding it in Linux.
> 
> The PMU node is not visible to S-mode SW (U-Boot proper or Linux) since
> it is only used to initialize the event counter mappings and erased in
> the generic_final_init() [2].

Sorry. It should be said that part of it (riscv,*event-to-mhpm* properties)
will be erased, not the entire node.

the higher stack can still find the pmu node:

  pmu {
      compatible = "riscv,pmu";
  }

> Thanks,
> Peter Lin
> 
> [1] https://github.com/riscv-software-src/opensbi/blob/v1.3.1/lib/sbi/sbi_pmu.c#L583
> [2] https://github.com/riscv-software-src/opensbi/blob/master/platform/generic/platform.c#L172
>