Re: [Qemu-devel] [RFC for-2.13 08/12] target/ppc: Make hash64_opts field mandatory for 64-bit hash MMUs

[Cédric Le Goater]

On 03/27/2018 06:37 AM, David Gibson wrote:
> Currently some cpus set the hash64_opts field in the class structure, with
> specific details of their variant of the 64-bit hash mmu.  For the
> remaining cpus with that mmu, ppc_hash64_realize() fills in defaults.
> 
> But there are only a couple of cpus that use those fallbacks, so just have
> them to set the has64_opts field instead, simplifying the logic.
> 
> Signed-off-by: David Gibson <address@hidden>


Reviewed-by: Cédric Le Goater <address@hidden>

> ---
>  target/ppc/mmu-hash64.c     | 36 ++++++++++++++++++------------------
>  target/ppc/mmu-hash64.h     |  1 +
>  target/ppc/translate_init.c |  2 ++
>  3 files changed, 21 insertions(+), 18 deletions(-)
> 
> diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c
> index d7a0e5615f..d369b1bf86 100644
> --- a/target/ppc/mmu-hash64.c
> +++ b/target/ppc/mmu-hash64.c
> @@ -1100,25 +1100,12 @@ void ppc_hash64_init(PowerPCCPU *cpu)
>      CPUPPCState *env = &cpu->env;
>      PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
>  
> -    if (pcc->hash64_opts) {
> -        cpu->hash64_opts = g_memdup(pcc->hash64_opts,
> -                                    sizeof(*cpu->hash64_opts));
> -    } else if (env->mmu_model & POWERPC_MMU_64) {
> -        /* Use default sets of page sizes. We don't support MPSS */
> -        static const PPCHash64Options defopts = {
> -            .sps = {
> -                { .page_shift = 12, /* 4K */
> -                  .slb_enc = 0,
> -                  .enc = { { .page_shift = 12, .pte_enc = 0 } }
> -                },
> -                { .page_shift = 24, /* 16M */
> -                  .slb_enc = 0x100,
> -                  .enc = { { .page_shift = 24, .pte_enc = 0 } }
> -                },
> -            },
> -        };
> -        cpu->hash64_opts = g_memdup(&defopts, sizeof(*cpu->hash64_opts));
> +    if (!pcc->hash64_opts) {
> +        assert(!(env->mmu_model & POWERPC_MMU_64));
> +        return;
>      }
> +
> +    cpu->hash64_opts = g_memdup(pcc->hash64_opts, sizeof(*cpu->hash64_opts));
>  }
>  
>  void ppc_hash64_finalize(PowerPCCPU *cpu)
> @@ -1126,6 +1113,19 @@ void ppc_hash64_finalize(PowerPCCPU *cpu)
>      g_free(cpu->hash64_opts);
>  }
>  
> +const PPCHash64Options ppc_hash64_opts_basic = {
> +    .sps = {
> +        { .page_shift = 12, /* 4K */
> +          .slb_enc = 0,
> +          .enc = { { .page_shift = 12, .pte_enc = 0 } }
> +        },
> +        { .page_shift = 24, /* 16M */
> +          .slb_enc = 0x100,
> +          .enc = { { .page_shift = 24, .pte_enc = 0 } }
> +        },
> +    },
> +};
> +
>  const PPCHash64Options ppc_hash64_opts_POWER7 = {
>      .sps = {
>          {
> diff --git a/target/ppc/mmu-hash64.h b/target/ppc/mmu-hash64.h
> index d42cbc2762..ff0c48af55 100644
> --- a/target/ppc/mmu-hash64.h
> +++ b/target/ppc/mmu-hash64.h
> @@ -155,6 +155,7 @@ struct PPCHash64Options {
>      struct ppc_one_seg_page_size sps[PPC_PAGE_SIZES_MAX_SZ];
>  };
>  
> +extern const PPCHash64Options ppc_hash64_opts_basic;
>  extern const PPCHash64Options ppc_hash64_opts_POWER7;
>  
>  #endif /* CONFIG_USER_ONLY */
> diff --git a/target/ppc/translate_init.c b/target/ppc/translate_init.c
> index 040d6fbac3..ae005b2a54 100644
> --- a/target/ppc/translate_init.c
> +++ b/target/ppc/translate_init.c
> @@ -8242,6 +8242,7 @@ POWERPC_FAMILY(970)(ObjectClass *oc, void *data)
>      pcc->mmu_model = POWERPC_MMU_64B;
>  #if defined(CONFIG_SOFTMMU)
>      pcc->handle_mmu_fault = ppc_hash64_handle_mmu_fault;
> +    pcc->hash64_opts = &ppc_hash64_opts_basic;
>  #endif
>      pcc->excp_model = POWERPC_EXCP_970;
>      pcc->bus_model = PPC_FLAGS_INPUT_970;
> @@ -8319,6 +8320,7 @@ POWERPC_FAMILY(POWER5P)(ObjectClass *oc, void *data)
>      pcc->mmu_model = POWERPC_MMU_2_03;
>  #if defined(CONFIG_SOFTMMU)
>      pcc->handle_mmu_fault = ppc_hash64_handle_mmu_fault;
> +    pcc->hash64_opts = &ppc_hash64_opts_basic;
>  #endif
>      pcc->excp_model = POWERPC_EXCP_970;
>      pcc->bus_model = PPC_FLAGS_INPUT_970;
>