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-rw-r--r--src/cpu/intel/haswell/Kconfig4
-rw-r--r--src/cpu/intel/haswell/haswell_init.c44
2 files changed, 48 insertions, 0 deletions
diff --git a/src/cpu/intel/haswell/Kconfig b/src/cpu/intel/haswell/Kconfig
index 9cda140657..9e62ae50ac 100644
--- a/src/cpu/intel/haswell/Kconfig
+++ b/src/cpu/intel/haswell/Kconfig
@@ -34,6 +34,10 @@ config SMM_TSEG_SIZE
hex
default 0x800000
+config ENABLE_VMX
+ bool "Enable VMX for virtualization"
+ default n
+
config IED_REGION_SIZE
hex
default 0x400000
diff --git a/src/cpu/intel/haswell/haswell_init.c b/src/cpu/intel/haswell/haswell_init.c
index 9fa9b48fe4..043ba3a580 100644
--- a/src/cpu/intel/haswell/haswell_init.c
+++ b/src/cpu/intel/haswell/haswell_init.c
@@ -150,6 +150,47 @@ static acpi_cstate_t cstate_map[NUM_C_STATES] = {
},
};
+static void enable_vmx(void)
+{
+ struct cpuid_result regs;
+ msr_t msr;
+ int enable = IS_ENABLED(CONFIG_ENABLE_VMX);
+
+ regs = cpuid(1);
+ /* Check that the VMX is supported before reading or writing the MSR. */
+ if (!((regs.ecx & CPUID_VMX) || (regs.ecx & CPUID_SMX)))
+ return;
+
+ msr = rdmsr(IA32_FEATURE_CONTROL);
+
+ if (msr.lo & (1 << 0)) {
+ printk(BIOS_ERR, "VMX is locked, so %s will do nothing\n", __func__);
+ /* VMX locked. If we set it again we get an illegal
+ * instruction
+ */
+ return;
+ }
+
+ /* The IA32_FEATURE_CONTROL MSR may initialize with random values.
+ * It must be cleared regardless of VMX config setting.
+ */
+ msr.hi = msr.lo = 0;
+
+ printk(BIOS_DEBUG, "%s VMX\n", enable ? "Enabling" : "Disabling");
+
+ if (enable) {
+ msr.lo |= (1 << 2);
+ if (regs.ecx & CPUID_SMX)
+ msr.lo |= (1 << 1);
+ }
+
+ wrmsr(IA32_FEATURE_CONTROL, msr);
+
+ msr.lo |= (1 << 0); /* Set lock bit */
+
+ wrmsr(IA32_FEATURE_CONTROL, msr);
+}
+
/* Convert time in seconds to POWER_LIMIT_1_TIME MSR value */
static const u8 power_limit_time_sec_to_msr[] = {
[0] = 0x00,
@@ -703,6 +744,9 @@ static void haswell_init(device_t cpu)
enable_lapic_tpr();
setup_lapic();
+ /* Enable virtualization if Kconfig option is set */
+ enable_vmx();
+
/* Configure C States */
configure_c_states();