Re: [Qemu-devel] [PATCH v2 08/10] ppc: Add POWER8 IAMR register

[Thomas Huth]

On 16.03.2016 14:13, Cédric Le Goater wrote:
> From: Benjamin Herrenschmidt <address@hidden>
> 
> With appropriate AMR-like masks. Not actually used by the translation
> logic at that point
> 
> Signed-off-by: Benjamin Herrenschmidt <address@hidden>
> [clg: changed spr_register_hv(SPR_IAMR) to spr_register_kvm_hv(SPR_IAMR)
>       changed gen_spr_amr() prototype ]
> Signed-off-by: Cédric Le Goater <address@hidden>
> ---
>  target-ppc/cpu.h            |  1 +
>  target-ppc/translate_init.c | 41 +++++++++++++++++++++++++++++++++++++++--
>  2 files changed, 40 insertions(+), 2 deletions(-)
> 
> diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h
> index 167c73f863b3..a3c4fb112a3e 100644
> --- a/target-ppc/cpu.h
> +++ b/target-ppc/cpu.h
> @@ -1360,6 +1360,7 @@ static inline int cpu_mmu_index (CPUPPCState *env, bool 
> ifetch)
>  #define SPR_BOOKE_CSRR0       (0x03A)
>  #define SPR_BOOKE_CSRR1       (0x03B)
>  #define SPR_BOOKE_DEAR        (0x03D)
> +#define SPR_IAMR              (0x03D)
>  #define SPR_BOOKE_ESR         (0x03E)
>  #define SPR_BOOKE_IVPR        (0x03F)
>  #define SPR_MPC_EIE           (0x050)
> diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c
> index 4514188ff07c..c78b532e8f3c 100644
> --- a/target-ppc/translate_init.c
> +++ b/target-ppc/translate_init.c
> @@ -1126,9 +1126,39 @@ static void spr_write_uamor(DisasContext *ctx, int 
> sprn, int gprn)
>      tcg_temp_free(t1);
>      tcg_temp_free(t2);
>  }
> +
> +static void spr_write_iamr(DisasContext *ctx, int sprn, int gprn)
> +{
> +    TCGv t0 = tcg_temp_new();
> +    TCGv t1 = tcg_temp_new();
> +    TCGv t2 = tcg_temp_new();
> +
> +    /* Note, the HV=1 case is handled earlier by simply using
> +     * spr_write_generic for HV mode in the SPR table
> +     */
> +
> +    /* Build insertion mask into t1 based on context */
> +    gen_load_spr(t1, SPR_AMOR);
> +
> +    /* Mask new bits into t2 */
> +    tcg_gen_and_tl(t2, t1, cpu_gpr[gprn]);
> +
> +    /* Load AMR and clear new bits in t0 */
> +    gen_load_spr(t0, SPR_IAMR);
> +    tcg_gen_andc_tl(t0, t0, t1);
> +
> +    /* Or'in new bits and write it out */
> +    tcg_gen_or_tl(t0, t0, t2);
> +    gen_store_spr(SPR_IAMR, t0);
> +    spr_store_dump_spr(SPR_IAMR);
> +
> +    tcg_temp_free(t0);
> +    tcg_temp_free(t1);
> +    tcg_temp_free(t2);
> +}
>  #endif /* CONFIG_USER_ONLY */
>  
> -static void gen_spr_amr (CPUPPCState *env)
> +static void gen_spr_amr(CPUPPCState *env, bool has_iamr)
>  {
>  #ifndef CONFIG_USER_ONLY
>      /* Virtual Page Class Key protection */
> @@ -1154,6 +1184,13 @@ static void gen_spr_amr (CPUPPCState *env)
>                      SPR_NOACCESS, SPR_NOACCESS,
>                      &spr_read_generic, &spr_write_generic,
>                      0);
> +    if (!has_iamr) {
> +        spr_register_kvm_hv(env, SPR_IAMR, "IAMR",
> +                            SPR_NOACCESS, SPR_NOACCESS,
> +                            &spr_read_generic, &spr_write_iamr,
> +                            &spr_read_generic, &spr_write_generic,
> +                            KVM_REG_PPC_IAMR, 0);
> +    }

That should be now a "if (has_iamr)" instead of "if (!has_iamr)",
shouldn't it?

 Thomas