[Linaro-acpi] [PATCH v7 00/17] Introduce ACPI for ARM64 based on ACPI 5.1

Arnd Bergmann
2015-01-16T15:53:33Z

On Friday 16 January 2015 15:49:13 Will Deacon wrote:
>
> The on-board ethernet on Seattle requires the driver to program its AXI
> attributes, so configuring it to be a coherent master actually means
> "program the same cacheable AXI settings as you have on the CPU". That
> sounds like Linux should be doing it to me, but even if the firmware takes
> a guess at "normal cacheable WBRWA", it's not clear to me whether that
> register persists across things like adapter reset.
>
> Tom?
>
> There's also the situation where the firmware hasn't initialised the
> register and Linux realises this during probe. What should it do then?

In case of a 10gbit ethernet adapter, there really should be no question
regarding whether to set it coherent or not. Can't Linux just always
set this AXI attribute in the driver?

Arnd