Re: [Qemu-devel] [PATCH for-2.11] target/arm: Report GICv3 sysregs present in ID registers if needed

[Richard Henderson <richard.henderson@linaro.org>]

On 11/07/2017 04:01 PM, Peter Maydell wrote:
> The CPU ID registers ID_AA64PFR0_EL1, ID_PFR1_EL1 and ID_PFR1
> have a field for reporting presence of GICv3 system registers.
> We need to report this field correctly in order for Xen to
> work as a guest inside QEMU emulation. We mustn't incorrectly
> claim the sysregs exist when they don't, though, or Linux will
> crash.
> 
> Unfortunately the way we've designed the GICv3 emulation in QEMU
> puts the system registers as part of the GICv3 device, which
> may be created after the CPU proper has been realized. This
> means that we don't know at the point when we define the ID
> registers what the correct value is. Handle this by switching
> them to calling a function at runtime to read the value, where
> we can fill in the GIC field appropriately.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~