[PATCH v4 1/2] target/i386: add support for LAM in CPUID enumeration

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From: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>

Linear Address Masking (LAM) is a new Intel CPU feature, which allows
software to use of the untranslated address bits for metadata.

The bit definition:
CPUID.(EAX=7,ECX=1):EAX[26]

Add CPUID definition for LAM.

Note LAM feature is not supported for TCG of target-i386, LAM CPIUD bit
will not be added to TCG_7_1_EAX_FEATURES.

More info can be found in Intel ISE Chapter "LINEAR ADDRESS MASKING(LAM)"
https://cdrdv2.intel.com/v1/dl/getContent/671368

Signed-off-by: Robert Hoo <robert.hu@xxxxxxxxxxxxxxx>
Co-developed-by: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
Signed-off-by: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
Tested-by: Xuelian Guo <xuelian.guo@xxxxxxxxx>
Reviewed-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
---
 target/i386/cpu.c | 2 +-
 target/i386/cpu.h | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 2524881ce2..fc862dfeb1 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -967,7 +967,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             "fsrc", NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, "amx-fp16", NULL, "avx-ifma",
-            NULL, NULL, NULL, NULL,
+            NULL, NULL, "lam", NULL,
             NULL, NULL, NULL, NULL,
         },
         .cpuid = {
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 7f0786e8b9..18ea755644 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -925,6 +925,8 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
 #define CPUID_7_1_EAX_AMX_FP16          (1U << 21)
 /* Support for VPMADD52[H,L]UQ */
 #define CPUID_7_1_EAX_AVX_IFMA          (1U << 23)
+/* Linear Address Masking */
+#define CPUID_7_1_EAX_LAM               (1U << 26)
 
 /* Support for VPDPB[SU,UU,SS]D[,S] */
 #define CPUID_7_1_EDX_AVX_VNNI_INT8     (1U << 4)
-- 
2.25.1





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