[Pdbg] [PATCH] main: Add P8 kernel devicetree

[Alistair Popple]

On Monday, 13 August 2018 4:13:56 PM AEST Joel Stanley wrote:
> On Mon, 13 Aug 2018 at 14:48, Alistair Popple <alistair at popple.id.au> wrote:
> >
> > Joel do you know if there is someway to differentiate between P8 and P9 on
> > OpenBMC? This patch makes it mandatory to specify p8 vs. p9 on the command line
> > which feels like a step backwards. If we can't do it from the BMC then we will
> > have to probe it from the host.
> 
> I spent more time than I'd like to admit looking at this last week.

Thanks!

> We could assume that ast2400 == p8, as it is true for all the machines
> that exist to date.
> 
> I looked into geteauxval etc, but it appears there's no way to detect
> you're on an ast2400 (or even just an ARM9) without parsing files. So
> the 'best' we have would be to open up the device tree at
> /sys/firmware, or parse /proc/cpuinfo.
> 
> The device tree would be neater.

Ok. I guess we already have stuff to read the device-tree for the FSI
bit-banging backend so we could use that. But it would be better to just probe
the host CFAM and read it from there. Means the host has to be powered on, but
if it isn't pdbg won't be able to do much anyway.

- Alistair

> Cheers,
> 
> Joel
>