i386/cpu: Add support for AVX10_VNNI_INT in CPUID enumeration

AVX10_VNNI_INT (0x24.0x1.ECX[bit 2]) is a discrete feature bit
introduced on Intel Diamond Rapids, which enumerates the support for
EVEX VPDP* instructions for INT8/INT16 [*].

Although Intel AVX10.2 has already included new VPDP* INT8/INT16 VNNI
instructions, a bit - AVX10_VNNI_INT - is still be separated. Relevant
new instructions can be checked by either CPUID AVX10.2 OR
AVX10_VNNI_INT (e.g., VPDPBSSD).

Support CPUID 0x24.0x1 subleaf with AVX10_VNNI_INT enumeration for
Guest.

[*]: Intel Advanced Vector Extensions 10.2 Architecture Specification
     (rev 5.0).

Tested-by: Xudong Hao <xudong.hao@intel.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20251215073743.4055227-4-zhao1.liu@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 1246a9af4a3b54e372f2b891f2e0edd61a7f748a..e0d75d170fa46eb140bc020b0d35edd201d95347 100644 (file)
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1038,6 +1038,7 @@ void x86_cpu_vendor_words2str(char *dst, uint32_t vendor1,
 #define TCG_24_0_EBX_FEATURES 0
 #define TCG_29_0_EBX_FEATURES 0
 #define TCG_1E_1_EAX_FEATURES 0
+#define TCG_24_1_ECX_FEATURES 0
 
 #if defined CONFIG_USER_ONLY
 #define CPUID_8000_0008_EBX_KERNEL_FEATURES (CPUID_8000_0008_EBX_IBPB | \
@@ -1385,6 +1386,18 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         },
         .tcg_features = TCG_29_0_EBX_FEATURES,
     },
+    [FEAT_24_1_ECX] = {
+        .type = CPUID_FEATURE_WORD,
+        .feat_names = {
+            [2] = "avx10-vnni-int",
+        },
+        .cpuid = {
+            .eax = 0x24,
+            .needs_ecx = true, .ecx = 1,
+            .reg = R_ECX,
+        },
+        .tcg_features = TCG_24_1_ECX_FEATURES,
+    },
     [FEAT_8000_0007_EDX] = {
         .type = CPUID_FEATURE_WORD,
         .feat_names = {
@@ -2041,6 +2054,11 @@ static FeatureDep feature_dependencies[] = {
         .from = { FEAT_7_1_EDX,             CPUID_7_1_EDX_APXF },
         .to = { FEAT_29_0_EBX,              ~0ull },
     },
+
+    {
+        .from = { FEAT_7_1_EDX,             CPUID_7_1_EDX_AVX10 },
+        .to = { FEAT_24_1_ECX,              ~0ull },
+    },
 };
 
 typedef struct X86RegisterInfo32 {
@@ -8457,8 +8475,17 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index, uint32_t count,
         *ebx = 0;
         *ecx = 0;
         *edx = 0;
-        if ((env->features[FEAT_7_1_EDX] & CPUID_7_1_EDX_AVX10) && count == 0) {
+
+        if (!(env->features[FEAT_7_1_EDX] & CPUID_7_1_EDX_AVX10)) {
+            break;
+        }
+        if (count == 0) {
+            uint32_t unused;
+            x86_cpu_get_supported_cpuid(0x1E, 0, eax, &unused,
+                                        &unused, &unused);
             *ebx = env->features[FEAT_24_0_EBX] | env->avx10_version;
+        } else if (count == 1) {
+            *ecx = env->features[FEAT_24_1_ECX];
         }
         break;
     }

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 7b002962e23f930a568c8fc3f6e0abe86d2cf1c0..653f14e516cf3a061161a1e2a7579b0b5d4764fd 100644 (file)
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -712,6 +712,7 @@ typedef enum FeatureWord {
     FEAT_24_0_EBX,      /* CPUID[EAX=0x24,ECX=0].EBX */
     FEAT_29_0_EBX,      /* CPUID[EAX=0x29,ECX=0].EBX */
     FEAT_1E_1_EAX,      /* CPUID[EAX=0x1E,ECX=1].EAX */
+    FEAT_24_1_ECX,      /* CPUID[EAX=0x24,ECX=0].ECX */
     FEATURE_WORDS,
 } FeatureWord;
 
@@ -1113,6 +1114,9 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu, FeatureWord w);
                                          CPUID_24_0_EBX_AVX10_256 | \
                                          CPUID_24_0_EBX_AVX10_512)
 
+/* AVX10_VNNI_INT instruction */
+#define CPUID_24_1_ECX_AVX10_VNNI_INT         (1U << 2)
+
 /*
  * New Conditional Instructions (NCIs), explicit New Data Destination (NDD)
  * controls, and explicit Flags Suppression (NF) controls for select sets of