Re: [PATCH 09/14] target/arm: Support CP_ACCESS_TRAP_EL1 as a CPAccessResult

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

On 1/30/25 10:23, Peter Maydell wrote:
> In the CPAccessResult enum, the CP_ACCESS_TRAP* values indicate the
> equivalent of the pseudocode AArch64.SystemAccessTrap(..., 0x18),
> causing a trap to a specified exception level with a syndrome value
> giving information about the failing instructions.  In the
> pseudocode, such traps are always taken to a specified target EL.  We
> support that for target EL of 2 or 3 via CP_ACCESS_TRAP_EL2 and
> CP_ACCESS_TRAP_EL3, but the only way to take the access trap to EL1
> currently is to use CP_ACCESS_TRAP, which takes the trap to the
> "usual target EL" (EL1 if in EL0, otherwise to the current EL).
> 
> Add CP_ACCESS_TRAP_EL1 so that access functions can follow the
> pseudocode more closely.
> 
> (Note that for the common case in the pseudocode of "trap to
> EL2 if HCR_EL2.TGE is set, otherwise trap to EL1", we handle
> this in raise_exception(), so access functions don't need to
> special case it and can use CP_ACCESS_TRAP_EL1.)
> 
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> ---
>   target/arm/cpregs.h        | 1 +
>   target/arm/tcg/op_helper.c | 6 ++++--
>   2 files changed, 5 insertions(+), 2 deletions(-)

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

r~