On 12/01/2017 10:44 AM, Peter Maydell wrote:
> For M profile, we currently have an mmu index MNegPri for
> "requested execution priority negative". This fails to
> distinguish "requested execution priority negative, privileged"
> from "requested execution priority negative, usermode", but
> the two can return different results for MPU lookups. Fix this
> by splitting MNegPri into MNegPriPriv and MNegPriUser, and
> similarly for the Secure equivalent MSNegPri.
>
> This takes us from 6 M profile MMU modes to 8, which means
> we need to bump NB_MMU_MODES; this is OK since the point
> where we are forced to reduce TLB sizes is 9 MMU modes.
>
> (It would in theory be possible to stick with 6 MMU indexes:
> {mpu-disabled,user,privileged} x {secure,nonsecure} since
> in the MPU-disabled case the result of an MPU lookup is
> always the same for both user and privileged code. However
> we would then need to rework the TB flags handling to put
> user/priv into the TB flags separately from the mmuidx.
> Adding an extra couple of mmu indexes is simpler.)
>
> Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
> ---
> target/arm/cpu.h | 49 ++++++++++++++++++++++++++++---------------------
> target/arm/internals.h | 6 ++++--
> target/arm/helper.c | 14 ++++++++++----
> target/arm/translate.c | 8 ++++++--
> 4 files changed, 48 insertions(+), 29 deletions(-)
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
r~
