soc/intel/common/block: add VMX support

Enable VMX if supported by CPU and enabled in board devicetree.
Check lock bit unset before enabling VMX.

Change-Id: Ic57eac45e9c65baa4479735c6d70a7eb685f080e
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/25331
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/common/block/include/intelblocks/msr.h

@@ -19,6 +19,7 @@
 #define MSR_CORE_THREAD_COUNT	0x35
 #define IA32_FEATURE_CONTROL	0x3a
 #define  FEATURE_CONTROL_LOCK	(1)
+#define  FEATURE_ENABLE_VMX	(1 << 2)
 #define  CPUID_VMX		(1 << 5)
 #define  CPUID_SMX		(1 << 6)
 #define  SGX_GLOBAL_ENABLE	(1 << 18)

src/soc/intel/common/block/include/intelblocks/vmx.h

@@ -0,0 +1,30 @@
+/*
+ * 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 SOC_INTEL_COMMON_BLOCK_VMX_H
+#define SOC_INTEL_COMMON_BLOCK_VMX_H
+
+struct vmx_param {
+	uint8_t enable;
+};
+
+/*
+ * Configure VMX.
+ */
+void vmx_configure(void);
+
+/* SOC specific API to get VMX params.
+ * returns 0, if able to get VMX params; otherwise returns -1 */
+int soc_fill_vmx_param(struct vmx_param *vmx_param);
+
+#endif	/* SOC_INTEL_COMMON_BLOCK_VMX_H */

src/soc/intel/common/block/vmx/Kconfig

@@ -0,0 +1,3 @@
+config SOC_INTEL_COMMON_BLOCK_VMX
+	bool "Enable VMX for virtualization"
+	default n

src/soc/intel/common/block/vmx/Makefile.inc

@@ -0,0 +1 @@
+ramstage-$(CONFIG_SOC_INTEL_COMMON_BLOCK_VMX) += vmx.c

src/soc/intel/common/block/vmx/vmx.c

@@ -0,0 +1,72 @@
+/*
+ * 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.
+ */
+
+#include <console/console.h>
+#include <cpu/x86/msr.h>
+#include <intelblocks/msr.h>
+#include <intelblocks/vmx.h>
+#include <soc/cpu.h>
+#include <string.h>
+
+static bool vmx_param_valid;
+static struct vmx_param g_vmx_param;
+
+static const struct vmx_param *get_vmx_param(void)
+{
+	if (vmx_param_valid)
+		return &g_vmx_param;
+
+	memset(&g_vmx_param, 0, sizeof(g_vmx_param));
+	if (soc_fill_vmx_param(&g_vmx_param) < 0) {
+		printk(BIOS_ERR, "VMX : Failed to get soc vmx param\n");
+		return NULL;
+	}
+	vmx_param_valid = true;
+	printk(BIOS_INFO, "VMX : param.enable = %d\n", g_vmx_param.enable);
+
+	return &g_vmx_param;
+}
+
+static int soc_vmx_enabled(void)
+{
+	const struct vmx_param *vmx_param = get_vmx_param();
+	return vmx_param ? vmx_param->enable : 0;
+}
+
+void vmx_configure(void)
+{
+	msr_t msr;
+	struct cpuid_result regs;
+
+	regs = cpuid(1);
+
+	if (!soc_vmx_enabled() || !(regs.ecx & CPUID_VMX)) {
+		printk(BIOS_ERR, "VMX: pre-conditions not met\n");
+		return;
+	}
+
+	msr = rdmsr(IA32_FEATURE_CONTROL);
+
+	/* Only enable it when it is not locked */
+	if ((msr.lo & FEATURE_CONTROL_LOCK) == 0) {
+		/* Enable VMX */
+		msr.lo |= FEATURE_ENABLE_VMX;
+		wrmsr(IA32_FEATURE_CONTROL, msr);
+	}
+
+	/* Report current status */
+	msr = rdmsr(IA32_FEATURE_CONTROL);
+	printk(BIOS_DEBUG, "VMX status: %s, %s\n",
+		(msr.lo & FEATURE_ENABLE_VMX) ? "enabled" : "disabled",
+		(msr.lo & FEATURE_CONTROL_LOCK) ? "locked" : "unlocked");
+}