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authorLinus Torvalds <torvalds@linux-foundation.org>2022-10-04 19:06:35 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2022-10-04 19:06:35 +0300
commit3339914a5832cffdecd578931b3db20d3deba5f6 (patch)
treef25be22a4ba5f16d7775d9d0fecd155659379e3e
parentbf7676251b49cc4a97572da7e10f52b97cf65c75 (diff)
parent81a71f51b89e84f39df2a3b1daf4274ae6b7b194 (diff)
downloadlinux-3339914a5832cffdecd578931b3db20d3deba5f6.tar.xz
Merge tag 'x86_platform_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 platform update from Borislav Petkov: "A single x86/platform improvement when the kernel is running as an ACRN guest: - Get TSC and CPU frequency from CPUID leaf 0x40000010 when the kernel is running as a guest on the ACRN hypervisor" * tag 'x86_platform_for_v6.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/acrn: Set up timekeeping
-rw-r--r--arch/x86/include/asm/acrn.h14
-rw-r--r--arch/x86/kernel/cpu/acrn.c3
2 files changed, 17 insertions, 0 deletions
diff --git a/arch/x86/include/asm/acrn.h b/arch/x86/include/asm/acrn.h
index e003a01b7c67..1dd14381bcb6 100644
--- a/arch/x86/include/asm/acrn.h
+++ b/arch/x86/include/asm/acrn.h
@@ -10,6 +10,15 @@
/* Bit 0 indicates whether guest VM is privileged */
#define ACRN_FEATURE_PRIVILEGED_VM BIT(0)
+/*
+ * Timing Information.
+ * This leaf returns the current TSC frequency in kHz.
+ *
+ * EAX: (Virtual) TSC frequency in kHz.
+ * EBX, ECX, EDX: RESERVED (reserved fields are set to zero).
+ */
+#define ACRN_CPUID_TIMING_INFO 0x40000010
+
void acrn_setup_intr_handler(void (*handler)(void));
void acrn_remove_intr_handler(void);
@@ -21,6 +30,11 @@ static inline u32 acrn_cpuid_base(void)
return 0;
}
+static inline unsigned long acrn_get_tsc_khz(void)
+{
+ return cpuid_eax(ACRN_CPUID_TIMING_INFO);
+}
+
/*
* Hypercalls for ACRN
*
diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
index 23f5f27b5a02..485441b7f030 100644
--- a/arch/x86/kernel/cpu/acrn.c
+++ b/arch/x86/kernel/cpu/acrn.c
@@ -28,6 +28,9 @@ static void __init acrn_init_platform(void)
{
/* Setup the IDT for ACRN hypervisor callback */
alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, asm_sysvec_acrn_hv_callback);
+
+ x86_platform.calibrate_tsc = acrn_get_tsc_khz;
+ x86_platform.calibrate_cpu = acrn_get_tsc_khz;
}
static bool acrn_x2apic_available(void)