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-rw-r--r--src/cpu/intel/common/Kconfig23
-rw-r--r--src/cpu/intel/common/Makefile.inc1
-rw-r--r--src/cpu/intel/common/common.h20
-rw-r--r--src/cpu/intel/common/common_init.c71
4 files changed, 115 insertions, 0 deletions
diff --git a/src/cpu/intel/common/Kconfig b/src/cpu/intel/common/Kconfig
new file mode 100644
index 0000000000..739333e4aa
--- /dev/null
+++ b/src/cpu/intel/common/Kconfig
@@ -0,0 +1,23 @@
+config CPU_INTEL_COMMON
+ bool
+
+if CPU_INTEL_COMMON
+
+config ENABLE_VMX
+ bool "Enable VMX for virtualization"
+ default y
+
+config SET_VMX_LOCK_BIT
+ bool "Set lock bit after configuring VMX"
+ depends on ENABLE_VMX
+ default y
+ help
+ Although the Intel manual says you must set the lock bit in addition
+ to the VMX bit in order for VMX to work, this isn't strictly true, so
+ we have the option to leave it unlocked and allow the OS (e.g. Linux)
+ to manage things itself. This is beneficial for testing purposes as
+ there is no need to reflash the firmware just to toggle the lock bit.
+ However, leaving the lock bit unset will break Windows' detection of
+ VMX support and built-in virtualization features like Hyper-V.
+
+endif
diff --git a/src/cpu/intel/common/Makefile.inc b/src/cpu/intel/common/Makefile.inc
new file mode 100644
index 0000000000..1e94ec92e4
--- /dev/null
+++ b/src/cpu/intel/common/Makefile.inc
@@ -0,0 +1 @@
+ramstage-y += common_init.c
diff --git a/src/cpu/intel/common/common.h b/src/cpu/intel/common/common.h
new file mode 100644
index 0000000000..0d0b954886
--- /dev/null
+++ b/src/cpu/intel/common/common.h
@@ -0,0 +1,20 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _CPU_INTEL_COMMON_H
+#define _CPU_INTEL_COMMON_H
+
+void set_vmx(void);
+
+#endif
diff --git a/src/cpu/intel/common/common_init.c b/src/cpu/intel/common/common_init.c
new file mode 100644
index 0000000000..da7b82651f
--- /dev/null
+++ b/src/cpu/intel/common/common_init.c
@@ -0,0 +1,71 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2007-2009 coresystems GmbH
+ * Copyright (C) 2011 The ChromiumOS Authors. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <console/console.h>
+#include <cpu/x86/msr.h>
+#include "common.h"
+
+#define IA32_FEATURE_CONTROL 0x3a
+#define CPUID_VMX (1 << 5)
+#define CPUID_SMX (1 << 6)
+
+void set_vmx(void)
+{
+ struct cpuid_result regs;
+ msr_t msr;
+ int enable = IS_ENABLED(CONFIG_ENABLE_VMX);
+ int lock = IS_ENABLED(CONFIG_SET_VMX_LOCK_BIT);
+
+ regs = cpuid(1);
+ /* Check that the VMX is supported before reading or writing the MSR. */
+ if (!((regs.ecx & CPUID_VMX) || (regs.ecx & CPUID_SMX))) {
+ printk(BIOS_DEBUG, "CPU doesn't support VMX; exiting\n");
+ 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;
+
+ if (enable) {
+ msr.lo |= (1 << 2);
+ if (regs.ecx & CPUID_SMX)
+ msr.lo |= (1 << 1);
+ }
+
+ wrmsr(IA32_FEATURE_CONTROL, msr);
+
+ if (lock) {
+ /* Set lock bit */
+ msr.lo |= (1 << 0);
+ wrmsr(IA32_FEATURE_CONTROL, msr);
+ }
+
+ printk(BIOS_DEBUG, "VMX status: %s, %s\n", enable ? "enabled" : "disabled",
+ lock ? "locked" : "unlocked");
+}