Re: [Qemu-devel] [PATCH] target-arm: Add MDCR_EL2

[Peter Maydell]

On 28 September 2015 at 11:37, Sergey Fedorov <address@hidden> wrote:
> Signed-off-by: Sergey Fedorov <address@hidden>
> ---
>
> This patch is a prerequisite for a debug exception routing patch:
> https://lists.gnu.org/archive/html/qemu-devel/2015-09/msg03542.html
>
>  target-arm/cpu-qom.h |  1 +
>  target-arm/cpu.c     |  1 +
>  target-arm/cpu.h     |  1 +
>  target-arm/cpu64.c   |  1 +
>  target-arm/helper.c  | 13 +++++++++++++
>  5 files changed, 17 insertions(+)
>
> diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h
> index 25fb1ce..d2b0769 100644
> --- a/target-arm/cpu-qom.h
> +++ b/target-arm/cpu-qom.h
> @@ -167,6 +167,7 @@ typedef struct ARMCPU {
>      uint64_t id_aa64mmfr0;
>      uint64_t id_aa64mmfr1;
>      uint32_t dbgdidr;
> +    uint32_t mdcr;

This field should be named mdcr_el2 if we have it, but:
the reset value for this register is defined architecturally,
so we don't need to specify it per CPU. (It's "all 0s, except
the bottom field resets to the same value as PMCR.N". Strictly
speaking some fields are defined to be architecturally
unknown and so might differ per CPU, but only in ways which
a guest doesn't care about. We typically model these in
the same way for all guest CPUs in QEMU.)

thanks
-- PMM