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From f33880c5f7a4e2cad25c22112da073273c6e2cfb Mon Sep 17 00:00:00 2001
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Date: Wed, 24 Feb 2021 11:30:35 -0500
Subject: [PATCH 2/4] target/i386: add fast short REP MOV support

RH-Author: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: <20210224113037.15599-3-dgilbert@redhat.com>
Patchwork-id: 101201
O-Subject: [RHEL-8.4.0 qemu-kvm PATCH 2/4] target/i386: add fast short REP MOV support
Bugzilla: 1790620
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>
RH-Acked-by: Sergio Lopez Pascual <slp@redhat.com>
RH-Acked-by: Peter Xu <peterx@redhat.com>

From: Chenyi Qiang <chenyi.qiang@intel.com>

For CPUs support fast short REP MOV[CPUID.(EAX=7,ECX=0):EDX(bit4)], e.g
Icelake and Tigerlake, expose it to the guest VM.

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20200714084148.26690-2-chenyi.qiang@intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
(cherry picked from commit 5cb287d2bd578dfe4897458793b4fce35bc4f744)
Signed-off-by: Danilo C. L. de Paula <ddepaula@redhat.com>
---
 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 67dab94aa5..f6a9ed84b3 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1077,7 +1077,7 @@ static FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
         .type = CPUID_FEATURE_WORD,
         .feat_names = {
             NULL, NULL, "avx512-4vnniw", "avx512-4fmaps",
-            NULL, NULL, NULL, NULL,
+            "fsrm", NULL, NULL, NULL,
             "avx512-vp2intersect", NULL, "md-clear", NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL /* pconfig */, NULL,
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 8e2e52ed31..f5a4efcec6 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -770,6 +770,8 @@ typedef uint64_t FeatureWordArray[FEATURE_WORDS];
 #define CPUID_7_0_EDX_AVX512_4VNNIW     (1U << 2)
 /* AVX512 Multiply Accumulation Single Precision */
 #define CPUID_7_0_EDX_AVX512_4FMAPS     (1U << 3)
+/* Fast Short Rep Mov */
+#define CPUID_7_0_EDX_FSRM              (1U << 4)
 /* AVX512 Vector Pair Intersection to a Pair of Mask Registers */
 #define CPUID_7_0_EDX_AVX512_VP2INTERSECT (1U << 8)
 /* Speculation Control */
-- 
2.27.0