Re: [PATCH v3 1/6] i386: Introduce FeatureWordInfo for AMX CPUID leaf 0x1D and 0x1E

[Yuan Yao]

On Fri, Jan 06, 2023 at 12:38:21AM -0800, Lei Wang wrote:
> CPUID leaf 0x1D and 0x1E enumerate tile and TMUL information for AMX.
>
> Introduce FeatureWord FEAT_1D_1_EAX, FEAT_1D_1_EBX, FEAT_1D_1_ECX and
> FEAT_1E_0_EBX. Thus these features of AMX can be expanded when
> "-cpu host/max" and can be configured in named CPU model.
>
> Signed-off-by: Lei Wang <lei4.wang@intel.com>

Reviewed-by: Yao Yuan <yuan.yao@intel.com>

> ---
>  target/i386/cpu.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++
>  target/i386/cpu.h | 12 +++++++++++
>  2 files changed, 67 insertions(+)
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index 3410e5e470..b6d1247e5e 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -1002,6 +1002,45 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
>          },
>          .tcg_features = ~0U,
>      },
> +    [FEAT_1D_1_EAX] = {
> +        .type = CPUID_FEATURE_WORD,
> +        .cpuid = {
> +            .eax = 0x1D,
> +            .needs_ecx = true, .ecx = 1,
> +            .reg = R_EAX,
> +        },
> +        .migratable_flags = CPUID_AMX_PALETTE_1_TOTAL_TILE_BYTES_MASK |
> +            CPUID_AMX_PALETTE_1_BYTES_PER_TILE_MASK,
> +    },
> +    [FEAT_1D_1_EBX] = {
> +        .type = CPUID_FEATURE_WORD,
> +        .cpuid = {
> +            .eax = 0x1D,
> +            .needs_ecx = true, .ecx = 1,
> +            .reg = R_EBX,
> +        },
> +        .migratable_flags = CPUID_AMX_PALETTE_1_BYTES_PER_ROW_MASK |
> +            CPUID_AMX_PALETTE_1_MAX_NAMES_MASK,
> +    },
> +    [FEAT_1D_1_ECX] = {
> +        .type = CPUID_FEATURE_WORD,
> +        .cpuid = {
> +            .eax = 0x1D,
> +            .needs_ecx = true, .ecx = 1,
> +            .reg = R_ECX,
> +        },
> +        .migratable_flags = CPUID_AMX_PALETTE_1_MAX_ROWS_MASK,
> +    },
> +    [FEAT_1E_0_EBX] = {
> +        .type = CPUID_FEATURE_WORD,
> +        .cpuid = {
> +            .eax = 0x1E,
> +            .needs_ecx = true, .ecx = 0,
> +            .reg = R_EBX,
> +        },
> +        .migratable_flags = CPUID_AMX_TMUL_MAX_K_MASK |
> +            CPUID_AMX_TMUL_MAX_N_MASK,
> +    },
>      /*Below are MSR exposed features*/
>      [FEAT_ARCH_CAPABILITIES] = {
>          .type = MSR_FEATURE_WORD,
> @@ -1371,6 +1410,22 @@ static FeatureDep feature_dependencies[] = {
>          .from = { FEAT_7_0_EBX,             CPUID_7_0_EBX_INTEL_PT },
>          .to = { FEAT_14_0_ECX,              ~0ull },
>      },
> +    {
> +        .from = { FEAT_7_0_EDX,             CPUID_7_0_EDX_AMX_TILE },
> +        .to = { FEAT_1D_1_EAX,              ~0ull },
> +    },
> +    {
> +        .from = { FEAT_7_0_EDX,             CPUID_7_0_EDX_AMX_TILE },
> +        .to = { FEAT_1D_1_EBX,              ~0ull },
> +    },
> +    {
> +        .from = { FEAT_7_0_EDX,             CPUID_7_0_EDX_AMX_TILE },
> +        .to = { FEAT_1D_1_ECX,              ~0ull },
> +    },
> +    {
> +        .from = { FEAT_7_0_EDX,             CPUID_7_0_EDX_AMX_TILE },
> +        .to = { FEAT_1E_0_EBX,              ~0ull },
> +    },
>      {
>          .from = { FEAT_8000_0001_EDX,       CPUID_EXT2_RDTSCP },
>          .to = { FEAT_VMX_SECONDARY_CTLS,    VMX_SECONDARY_EXEC_RDTSCP },
> diff --git a/target/i386/cpu.h b/target/i386/cpu.h
> index d4bc19577a..3e3e0cfe59 100644
> --- a/target/i386/cpu.h
> +++ b/target/i386/cpu.h
> @@ -585,6 +585,14 @@ typedef enum X86Seg {
>                                   XSTATE_Hi16_ZMM_MASK | XSTATE_PKRU_MASK | \
>                                   XSTATE_XTILE_CFG_MASK | 
> XSTATE_XTILE_DATA_MASK)
>
> +#define CPUID_AMX_PALETTE_1_TOTAL_TILE_BYTES_MASK 0xffffU
> +#define CPUID_AMX_PALETTE_1_BYTES_PER_TILE_MASK   (0xffffU << 16)
> +#define CPUID_AMX_PALETTE_1_BYTES_PER_ROW_MASK    0xffffU
> +#define CPUID_AMX_PALETTE_1_MAX_NAMES_MASK        (0xffffU << 16)
> +#define CPUID_AMX_PALETTE_1_MAX_ROWS_MASK         0xffffU
> +#define CPUID_AMX_TMUL_MAX_K_MASK                 0xffU
> +#define CPUID_AMX_TMUL_MAX_N_MASK                 (0xffffU << 8)
> +
>  /* CPUID feature words */
>  typedef enum FeatureWord {
>      FEAT_1_EDX,         /* CPUID[1].EDX */
> @@ -605,6 +613,10 @@ typedef enum FeatureWord {
>      FEAT_6_EAX,         /* CPUID[6].EAX */
>      FEAT_XSAVE_XCR0_LO, /* CPUID[EAX=0xd,ECX=0].EAX */
>      FEAT_XSAVE_XCR0_HI, /* CPUID[EAX=0xd,ECX=0].EDX */
> +    FEAT_1D_1_EAX,      /* CPUID[EAX=0x1d,ECX=1].EAX */
> +    FEAT_1D_1_EBX,      /* CPUID[EAX=0x1d,ECX=1].EBX */
> +    FEAT_1D_1_ECX,      /* CPUID[EAX=0x1d,ECX=1].ECX */
> +    FEAT_1E_0_EBX,      /* CPUID[EAX=0x1e,ECX=0].EBX */
>      FEAT_ARCH_CAPABILITIES,
>      FEAT_CORE_CAPABILITY,
>      FEAT_PERF_CAPABILITIES,
> --
> 2.34.1
>
>