Re: [Qemu-devel] [PATCH for-4.2 09/24] target/arm: Add TTBR1_EL2

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

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

> At the same time, add writefn to TTBR0_EL2 and TCR_EL2.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  target/arm/helper.c | 21 ++++++++++++++++-----
>  1 file changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/target/arm/helper.c b/target/arm/helper.c
> index d1bf31ab74..da2e0627b2 100644
> --- a/target/arm/helper.c
> +++ b/target/arm/helper.c
> @@ -3449,6 +3449,15 @@ static void vmsa_ttbr_el1_write(CPUARMState *env, const ARMCPRegInfo *ri,
>      }
>  }
>
> +static void vmsa_tcr_ttbr_el2_write(CPUARMState *env, const ARMCPRegInfo *ri,
> +                                    uint64_t value)
> +{
> +    raw_write(env, ri, value);

I wonder if the bellow would be better merged with:

  target/arm: Install asids for E2&0 translation regime

And the commit message amended to say something like:

  "later patches will potentially update the asid"

> +    if (arm_hcr_el2_eff(env) & HCR_E2H) {
> +        /* The ASID field is active.  */
> +    }
> +}
> +
>  static void vttbr_write(CPUARMState *env, const ARMCPRegInfo *ri,
>                          uint64_t value)
>  {
> @@ -4844,10 +4853,8 @@ static const ARMCPRegInfo el2_cp_reginfo[] = {
>        .resetvalue = 0 },
>      { .name = "TCR_EL2", .state = ARM_CP_STATE_BOTH,
>        .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 0, .opc2 = 2,
> -      .access = PL2_RW,
> -      /* no .writefn needed as this can't cause an ASID change;
> -       * no .raw_writefn or .resetfn needed as we never use mask/base_mask
> -       */
> +      .access = PL2_RW, .writefn = vmsa_tcr_ttbr_el2_write,
> +      /* no .raw_writefn or .resetfn needed as we never use mask/base_mask */
>        .fieldoffset = offsetof(CPUARMState, cp15.tcr_el[2]) },
>      { .name = "VTCR", .state = ARM_CP_STATE_AA32,
>        .cp = 15, .opc1 = 4, .crn = 2, .crm = 1, .opc2 = 2,
> @@ -4881,7 +4888,7 @@ static const ARMCPRegInfo el2_cp_reginfo[] = {
>        .fieldoffset = offsetof(CPUARMState, cp15.tpidr_el[2]) },
>      { .name = "TTBR0_EL2", .state = ARM_CP_STATE_AA64,
>        .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 0, .opc2 = 0,
> -      .access = PL2_RW, .resetvalue = 0,
> +      .access = PL2_RW, .resetvalue = 0, .writefn = vmsa_tcr_ttbr_el2_write,
>        .fieldoffset = offsetof(CPUARMState, cp15.ttbr0_el[2]) },
>      { .name = "HTTBR", .cp = 15, .opc1 = 4, .crm = 2,
>        .access = PL2_RW, .type = ARM_CP_64BIT | ARM_CP_ALIAS,
> @@ -6807,6 +6814,10 @@ void register_cp_regs_for_features(ARMCPU *cpu)
>                .opc0 = 3, .opc1 = 4, .crn = 13, .crm = 0, .opc2 = 1,
>                .access = PL2_RW,
>                .fieldoffset = offsetof(CPUARMState, cp15.contextidr_el[2]) },
> +            { .name = "TTBR1_EL2", .state = ARM_CP_STATE_AA64,
> +              .opc0 = 3, .opc1 = 4, .crn = 2, .crm = 0, .opc2 = 1,
> +              .access = PL2_RW, .writefn = vmsa_tcr_ttbr_el2_write,
> +              .fieldoffset = offsetof(CPUARMState, cp15.ttbr1_el[2]) },
>              REGINFO_SENTINEL
>          };
>          define_arm_cp_regs(cpu, vhe_reginfo);

Otherwise:

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

--
Alex Bennée