[Qemu-devel] [PATCH for-2.4] target-i386: add ABM to Haswell* and Broadwell* CPU models

[Qemu-devel] [PATCH for-2.4] target-i386: add ABM to Haswell* and Broadwell* CPU models

[Paolo Bonzini]

ABM is only implemented as a single instruction set by AMD; all AMD
processors support both instructions or neither. Intel considers POPCNT
as part of SSE4.2, and LZCNT as part of BMI1, but Intel also uses AMD's
ABM flag to indicate support for both POPCNT and LZCNT.  It has to be
added to Haswell and Broadwell because Haswell, by adding LZCNT, has
completed the ABM.

Tested with "qemu-kvm -cpu Haswell-noTSX,enforce" (and also with older
machine types) on an Haswell-EP machine.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/i386/pc_piix.c | 4 ++++
 hw/i386/pc_q35.c  | 4 ++++
 target-i386/cpu.c | 8 ++++----
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index e142f75..ce44313 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -307,6 +307,10 @@ static void pc_init1(MachineState *machine)
 static void pc_compat_2_3(MachineState *machine)
 {
     savevm_skip_section_footers();
+    x86_cpu_compat_set_features("Haswell", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
+    x86_cpu_compat_set_features("Haswell-noTSX", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
+    x86_cpu_compat_set_features("Broadwell", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
+    x86_cpu_compat_set_features("Broadwell-noTSX", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
 }
 
 static void pc_compat_2_2(MachineState *machine)
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 082cd93..f2f65b5 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -291,6 +291,10 @@ static void pc_q35_init(MachineState *machine)
 static void pc_compat_2_3(MachineState *machine)
 {
     savevm_skip_section_footers();
+    x86_cpu_compat_set_features("Haswell", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
+    x86_cpu_compat_set_features("Haswell-noTSX", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
+    x86_cpu_compat_set_features("Broadwell", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
+    x86_cpu_compat_set_features("Broadwell-noTSX", FEAT_8000_0001_ECX, 0, CPUID_EXT3_ABM);
 }
 
 static void pc_compat_2_2(MachineState *machine)
diff --git a/target-i386/cpu.c b/target-i386/cpu.c
index 4e7cdaa..50f659ac 100644
--- a/target-i386/cpu.c
+++ b/target-i386/cpu.c
@@ -1090,7 +1090,7 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT2_LM | CPUID_EXT2_RDTSCP | CPUID_EXT2_NX |
             CPUID_EXT2_SYSCALL,
         .features[FEAT_8000_0001_ECX] =
-            CPUID_EXT3_LAHF_LM,
+            CPUID_EXT3_ABM | CPUID_EXT3_LAHF_LM,
         .features[FEAT_7_0_EBX] =
             CPUID_7_0_EBX_FSGSBASE | CPUID_7_0_EBX_BMI1 |
             CPUID_7_0_EBX_AVX2 | CPUID_7_0_EBX_SMEP |
@@ -1123,7 +1123,7 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT2_LM | CPUID_EXT2_RDTSCP | CPUID_EXT2_NX |
             CPUID_EXT2_SYSCALL,
         .features[FEAT_8000_0001_ECX] =
-            CPUID_EXT3_LAHF_LM,
+            CPUID_EXT3_ABM | CPUID_EXT3_LAHF_LM,
         .features[FEAT_7_0_EBX] =
             CPUID_7_0_EBX_FSGSBASE | CPUID_7_0_EBX_BMI1 |
             CPUID_7_0_EBX_HLE | CPUID_7_0_EBX_AVX2 | CPUID_7_0_EBX_SMEP |
@@ -1158,7 +1158,7 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT2_LM | CPUID_EXT2_RDTSCP | CPUID_EXT2_NX |
             CPUID_EXT2_SYSCALL,
         .features[FEAT_8000_0001_ECX] =
-            CPUID_EXT3_LAHF_LM | CPUID_EXT3_3DNOWPREFETCH,
+            CPUID_EXT3_ABM | CPUID_EXT3_LAHF_LM | CPUID_EXT3_3DNOWPREFETCH,
         .features[FEAT_7_0_EBX] =
             CPUID_7_0_EBX_FSGSBASE | CPUID_7_0_EBX_BMI1 |
             CPUID_7_0_EBX_AVX2 | CPUID_7_0_EBX_SMEP |
@@ -1194,7 +1194,7 @@ static X86CPUDefinition builtin_x86_defs[] = {
             CPUID_EXT2_LM | CPUID_EXT2_RDTSCP | CPUID_EXT2_NX |
             CPUID_EXT2_SYSCALL,
         .features[FEAT_8000_0001_ECX] =
-            CPUID_EXT3_LAHF_LM | CPUID_EXT3_3DNOWPREFETCH,
+            CPUID_EXT3_ABM | CPUID_EXT3_LAHF_LM | CPUID_EXT3_3DNOWPREFETCH,
         .features[FEAT_7_0_EBX] =
             CPUID_7_0_EBX_FSGSBASE | CPUID_7_0_EBX_BMI1 |
             CPUID_7_0_EBX_HLE | CPUID_7_0_EBX_AVX2 | CPUID_7_0_EBX_SMEP |
-- 
2.4.3