cpu/intel/common: Add/Use common function to set virtualization

Migrate duplicated enable_vmx() method from multiple CPUs to common
folder.  Add common virtualization option for CPUs which support it.

Note that this changes the default to enable virtualization on CPUs
that support it.

Change-Id: Ib110bed6c9f5508e3f867dcdc6f341fc50e501d1
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/17874
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins)

3 files changed, 5 insertions, 56 deletions

diff --git a/src/cpu/intel/model_206ax/Kconfig b/src/cpu/intel/model_206ax/Kconfig
index b954b79c61..6c04fba829 100644
--- a/src/cpu/intel/model_206ax/Kconfig
+++ b/src/cpu/intel/model_206ax/Kconfig
@@ -20,6 +20,7 @@ config CPU_SPECIFIC_OPTIONS
 	#select AP_IN_SIPI_WAIT
 	select TSC_SYNC_MFENCE
 	select LAPIC_MONOTONIC_TIMER
+	select CPU_INTEL_COMMON
 
 config BOOTBLOCK_CPU_INIT
 	string
@@ -33,8 +34,4 @@ config SMM_TSEG_SIZE
 	hex
 	default 0x800000
 
-config ENABLE_VMX
-	bool "Enable VMX for virtualization"
-	default n
-
 endif
diff --git a/src/cpu/intel/model_206ax/Makefile.inc b/src/cpu/intel/model_206ax/Makefile.inc
index 25f07425dd..b79ccd71ff 100644
--- a/src/cpu/intel/model_206ax/Makefile.inc
+++ b/src/cpu/intel/model_206ax/Makefile.inc
@@ -1,6 +1,7 @@
 ramstage-y += model_206ax_init.c
 subdirs-y += ../../x86/name
 subdirs-y += ../smm/gen1
+subdirs-y += ../common
 
 ramstage-y += acpi.c
 
diff --git a/src/cpu/intel/model_206ax/model_206ax_init.c b/src/cpu/intel/model_206ax/model_206ax_init.c
index e7bfd9e298..af712d0db5 100644
--- a/src/cpu/intel/model_206ax/model_206ax_init.c
+++ b/src/cpu/intel/model_206ax/model_206ax_init.c
@@ -32,6 +32,7 @@
 #include "model_206ax.h"
 #include "chip.h"
 #include <cpu/intel/smm/gen1/smi.h>
+#include <cpu/intel/common/common.h>
 
 /*
  * List of supported C-states in this processor
@@ -110,56 +111,6 @@ static acpi_cstate_t cstate_map[] = {
 	{ 0 }
 };
 
-static void enable_vmx(void)
-{
-	struct cpuid_result regs;
-	msr_t msr;
-	int enable = 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");
-
-	/* Even though the Intel manual says you must set the lock bit in addition
-	 * to the VMX bit in order for VMX to work, it is incorrect.  Thus we leave
-	 * it unlocked for the OS to manage things itself.  This is good for a few
-	 * reasons:
-	 * - No need to reflash the bios just to toggle the lock bit.
-	 * - The VMX bits really really should match each other across cores, so
-	 *   hard locking it on one while another has the opposite setting can
-	 *   easily lead to crashes as code using VMX migrates between them.
-	 * - Vendors that want to "upsell" from a bios that disables+locks to
-	 *   one that doesn't is sleazy.
-	 * By leaving this to the OS (e.g. Linux), people can do exactly what they
-	 * want on the fly, and do it correctly (e.g. across multiple cores).
-	 */
-	if (enable) {
-		msr.lo |= (1 << 2);
-		if (regs.ecx & CPUID_SMX)
-			msr.lo |= (1 << 1);
-	}
-
-	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,
@@ -576,8 +527,8 @@ static void model_206ax_init(struct device *cpu)
 	enable_lapic_tpr();
 	setup_lapic();
 
-	/* Enable virtualization if enabled in CMOS */
-	enable_vmx();
+	/* Set virtualization based on Kconfig option */
+	set_vmx();
 
 	/* Configure C States */
 	configure_c_states();