[PATCH] x86/Centaur: show more HW features in /proc/cpuinfo

From: David Wang
Date: Sun Apr 08 2018 - 05:35:51 EST


We add this patch to show correct HW features(arch_perfmon, tpr_shadow,
vnmi, flexpriority, ept and vpid) when user execute "cat /proc/cpuinfo".

Signed-off-by: David Wang <davidwang@xxxxxxxxxxx>
---
arch/x86/kernel/cpu/centaur.c | 49 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)

diff --git a/arch/x86/kernel/cpu/centaur.c b/arch/x86/kernel/cpu/centaur.c
index e5ec0f1..969fb8f 100644
--- a/arch/x86/kernel/cpu/centaur.c
+++ b/arch/x86/kernel/cpu/centaur.c
@@ -112,6 +112,44 @@ static void early_init_centaur(struct cpuinfo_x86 *c)
}
}

+static void centaur_detect_vmx_virtcap(struct cpuinfo_x86 *c)
+{
+#define X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW 0x00200000
+#define X86_VMX_FEATURE_PROC_CTLS_VNMI 0x00400000
+#define X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS 0x80000000
+#define X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC 0x00000001
+#define X86_VMX_FEATURE_PROC_CTLS2_EPT 0x00000002
+#define X86_VMX_FEATURE_PROC_CTLS2_VPID 0x00000020
+
+ u32 vmx_msr_low, vmx_msr_high, msr_ctl, msr_ctl2;
+
+ clear_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
+ clear_cpu_cap(c, X86_FEATURE_VNMI);
+ clear_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
+ clear_cpu_cap(c, X86_FEATURE_EPT);
+ clear_cpu_cap(c, X86_FEATURE_VPID);
+
+ rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, vmx_msr_low, vmx_msr_high);
+ msr_ctl = vmx_msr_high | vmx_msr_low;
+
+ if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW)
+ set_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
+ if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_VNMI)
+ set_cpu_cap(c, X86_FEATURE_VNMI);
+ if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS) {
+ rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
+ vmx_msr_low, vmx_msr_high);
+ msr_ctl2 = vmx_msr_high | vmx_msr_low;
+ if ((msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC) &&
+ (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW))
+ set_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
+ if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_EPT)
+ set_cpu_cap(c, X86_FEATURE_EPT);
+ if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VPID)
+ set_cpu_cap(c, X86_FEATURE_VPID);
+ }
+}
+
static void init_centaur(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_32
@@ -128,6 +166,14 @@ static void init_centaur(struct cpuinfo_x86 *c)
clear_cpu_cap(c, 0*32+31);
#endif
early_init_centaur(c);
+
+ if (c->cpuid_level > 9) {
+ unsigned eax = cpuid_eax(10);
+ /* Check for version and the number of counters */
+ if ((eax & 0xff) && (((eax >> 8) & 0xff) > 1))
+ set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
+ }
+
switch (c->x86) {
#ifdef CONFIG_X86_32
case 5:
@@ -199,6 +245,9 @@ static void init_centaur(struct cpuinfo_x86 *c)
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
#endif
+
+ if (cpu_has(c, X86_FEATURE_VMX))
+ centaur_detect_vmx_virtcap(c);
}

#ifdef CONFIG_X86_32
--
1.9.1