Re: [Qemu-devel] [PATCH for-4.2 10/24] target/arm: Update CNTVCT_EL0 for VHE

["Alex Bennée" <alex.bennee@linaro.org>]

Richard Henderson <richard.henderson@linaro.org> writes:

> The virtual offset may be 0 depending on EL, E2H and TGE.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> ---
>  target/arm/helper.c | 40 +++++++++++++++++++++++++++++++++++++---
>  1 file changed, 37 insertions(+), 3 deletions(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index da2e0627b2..3124d682a2 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -2484,9 +2484,31 @@ static uint64_t gt_cnt_read(CPUARMState *env, const ARMCPRegInfo *ri)
>      return gt_get_countervalue(env);
>  }
>
> +static uint64_t gt_virt_cnt_offset(CPUARMState *env)
> +{
> +    uint64_t hcr;
> +
> +    switch (arm_current_el(env)) {
> +    case 2:
> +        hcr = arm_hcr_el2_eff(env);
> +        if (hcr & HCR_E2H) {
> +            return 0;
> +        }
> +        break;
> +    case 0:
> +        hcr = arm_hcr_el2_eff(env);
> +        if ((hcr & (HCR_E2H | HCR_TGE)) == (HCR_E2H | HCR_TGE)) {
> +            return 0;
> +        }
> +        break;
> +    }
> +
> +    return env->cp15.cntvoff_el2;
> +}
> +
>  static uint64_t gt_virt_cnt_read(CPUARMState *env, const ARMCPRegInfo *ri)
>  {
> -    return gt_get_countervalue(env) - env->cp15.cntvoff_el2;
> +    return gt_get_countervalue(env) - gt_virt_cnt_offset(env);
>  }
>
>  static void gt_cval_write(CPUARMState *env, const ARMCPRegInfo *ri,
> @@ -2501,7 +2523,13 @@ static void gt_cval_write(CPUARMState *env, const ARMCPRegInfo *ri,
>  static uint64_t gt_tval_read(CPUARMState *env, const ARMCPRegInfo *ri,
>                               int timeridx)
>  {
> -    uint64_t offset = timeridx == GTIMER_VIRT ? env->cp15.cntvoff_el2 : 0;
> +    uint64_t offset = 0;
> +
> +    switch (timeridx) {
> +    case GTIMER_VIRT:
> +        offset = gt_virt_cnt_offset(env);
> +        break;
> +    }
>
>      return (uint32_t)(env->cp15.c14_timer[timeridx].cval -
>                        (gt_get_countervalue(env) - offset));
> @@ -2511,7 +2539,13 @@ static void gt_tval_write(CPUARMState *env, const ARMCPRegInfo *ri,
>                            int timeridx,
>                            uint64_t value)
>  {
> -    uint64_t offset = timeridx == GTIMER_VIRT ? env->cp15.cntvoff_el2 : 0;
> +    uint64_t offset = 0;
> +
> +    switch (timeridx) {
> +    case GTIMER_VIRT:
> +        offset = gt_virt_cnt_offset(env);
> +        break;
> +    }
>
>      trace_arm_gt_tval_write(timeridx, value);
>      env->cp15.c14_timer[timeridx].cval = gt_get_countervalue(env) - offset +


--
Alex Bennée