Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

[Arnd Bergmann]

On Tue, Sep 7, 2021 at 2:27 PM Daniel Palmer <daniel@xxxxxxxx> wrote:
> On Tue, 7 Sept 2021 at 20:52, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> > > Off-topic but related:  Another MediaTek spin off, SigmaStar, seems to
> > > have done exactly the same thing. Cortex A53 chip running as a 32bit
> > > system to avoid having to fix their software. I'm interested to see if
> > > this makes it into arm or arm64. :)
> >
> > Maybe it's best to just add them to both at the same time? The boot
> > loader situation might take a bit to work out, but in theory this should
> > be fixable.
>
> I wonder how fixable it would be..
>
> I haven't gotten a board with the chip in question (SSD268G) yet but
> from looking at some firmware binaries I can see that even u-boot is a
> 6 year old 32bit version.
> As far as I can tell there's no PSCI, ATF etc that I think would be
> expected for an arm64 machine.

If the source code is available, creating a minimal PSCI implementation
in u-boot should be possible, and it would make it work well for both
32-bit and 64-bit kernels. There is no need for ATF here.

> I think the broken memory controller is still there so somehow I'd
> need to get the heavy barrier to work in arm64. I haven't yet worked
> out if that's even possible.

I think I missed that part of the discussion, or I forgot about it already.
What is the issue you are referring to here?

       Arnd