From 79eb86a5b9466cee19bc4e47429385a7244cdc4f Mon Sep 17 00:00:00 2001
From: Zhuocheng Ding <zhuocheng.ding@intel.corp-partner.google.com>
Date: Mon, 6 Dec 2021 14:52:03 +0800
Subject: [PATCH] x86: Expose hybrid CPU info to Guest

At present, when set host-cpu-topology option, the Guest still can't
get the hybrid information.

Now, for ADL, the hybrid related info is needed. These info include the
hybrid part flag (bit 15) in leaf 7 of CPUID, the core type and native
model id in leaf 1A of CPUID.

BUG=None
TEST=cargo build
TEST=Check the CPUID dump of Guest and Host

Change-Id: Icc03bc50160fdffc221e992d90225e7ed8081e8d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3314867
Reviewed-by: David Stevens <stevensd@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Commit-Queue: Daniel Verkamp <dverkamp@chromium.org>
---
 x86_64/src/cpuid.rs | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/x86_64/src/cpuid.rs b/x86_64/src/cpuid.rs
index 18f1e50089..428e901d2a 100644
--- a/x86_64/src/cpuid.rs
+++ b/x86_64/src/cpuid.rs
@@ -35,6 +35,7 @@ const ECX_TOPO_TYPE_SHIFT: u32 = 8; // Topology Level type.
 const ECX_TOPO_SMT_TYPE: u32 = 1; // SMT type.
 const ECX_TOPO_CORE_TYPE: u32 = 2; // CORE type.
 const EAX_CPU_CORES_SHIFT: u32 = 26; // Index of cpu cores in the same physical package.
+const EDX_HYBRID_CPU_SHIFT: u32 = 15; // Hybrid. The processor is identified as a hybrid part.
 
 fn filter_cpuid(
     vcpu_id: usize,
@@ -110,6 +111,26 @@ fn filter_cpuid(
                 // Clear X86 EPB feature.  No frequency selection in the hypervisor.
                 entry.ecx &= !(1 << ECX_EPB_SHIFT);
             }
+            7 => {
+                if host_cpu_topology && entry.index == 0 {
+                    // Safe because we pass 7 and 0 for this call and the host supports the
+                    // `cpuid` instruction
+                    let result = unsafe { __cpuid_count(entry.function, entry.index) };
+                    entry.edx |= result.edx & (1 << EDX_HYBRID_CPU_SHIFT);
+                }
+            }
+            0x1A => {
+                // Hybrid information leaf.
+                if host_cpu_topology {
+                    // Safe because we pass 0x1A for this call and the host supports the
+                    // `cpuid` instruction
+                    let result = unsafe { __cpuid(entry.function) };
+                    entry.eax = result.eax;
+                    entry.ebx = result.ebx;
+                    entry.ecx = result.ecx;
+                    entry.edx = result.edx;
+                }
+            }
             0xB | 0x1F => {
                 if host_cpu_topology {
                     continue;