1 files changed, 109 insertions, 0 deletions
diff --git a/src/vendorcode/google/chromeos/vbnv.c b/src/vendorcode/google/chromeos/vbnv.c
new file mode 100644
index 0000000000..2129461fc1
--- /dev/null
+++ b/src/vendorcode/google/chromeos/vbnv.c
@@ -0,0 +1,109 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <types.h>
+#include <string.h>
+#include <console/console.h>
+#include <pc80/mc146818rtc.h>
+#include <cpu/x86/car.h>
+#include "chromeos.h"
+
+#define VBNV_BLOCK_SIZE 16	/* Size of NV storage block in bytes */
+
+/* Constants for NV storage.  We use this rather than structs and
+ * bitfields so the data format is consistent across platforms and
+ * compilers.
+ */
+#define HEADER_OFFSET                0
+#define HEADER_MASK                     0xC0
+#define HEADER_SIGNATURE                0x40
+#define HEADER_FIRMWARE_SETTINGS_RESET  0x20
+#define HEADER_KERNEL_SETTINGS_RESET    0x10
+
+#define BOOT_OFFSET                  1
+#define BOOT_DEBUG_RESET_MODE           0x80
+#define BOOT_TRY_B_COUNT_MASK           0x0F
+
+#define RECOVERY_OFFSET              2
+#define LOCALIZATION_OFFSET          3
+
+#define DEV_FLAGS_OFFSET             4
+#define DEV_BOOT_USB_MASK               0x01
+
+#define FIRMWARE_FLAGS_OFFSET        5
+#define FIRMWARE_TEST_ERR_FUNC_MASK     0x38
+#define FIRMWARE_TEST_ERR_FUNC_SHIFT    3
+#define FIRMWARE_TEST_ERR_NUM_MASK      0x07
+
+#define KERNEL_FIELD_OFFSET         11
+#define CRC_OFFSET                  15
+
+static int vbnv_initialized CAR_GLOBAL;
+uint8_t vbnv[CONFIG_VBNV_SIZE] CAR_GLOBAL;
+
+/* Return CRC-8 of the data, using x^8 + x^2 + x + 1 polynomial.  A
+ * table-based algorithm would be faster, but for only 15 bytes isn't
+ * worth the code size.
+ */
+
+static uint8_t crc8(const uint8_t * data, int len)
+{
+	unsigned crc = 0;
+	int i, j;
+
+	for (j = len; j; j--, data++) {
+		crc ^= (*data << 8);
+		for (i = 8; i; i--) {
+			if (crc & 0x8000)
+				crc ^= (0x1070 << 3);
+			crc <<= 1;
+		}
+	}
+
+	return (uint8_t) (crc >> 8);
+}
+
+static void vbnv_setup(void)
+{
+	int i;
+
+	for (i = 0; i < CONFIG_VBNV_SIZE; i++)
+		vbnv[i] = cmos_read(CONFIG_VBNV_OFFSET + 14 + i);
+
+	/* Check data for consistency */
+	if ((HEADER_SIGNATURE != (vbnv[HEADER_OFFSET] & HEADER_MASK))
+	    || (crc8(vbnv, CRC_OFFSET) != vbnv[CRC_OFFSET])) {
+
+		/* Data is inconsistent (bad CRC or header),
+		 * so reset to defaults
+		 */
+		memset(vbnv, 0, VBNV_BLOCK_SIZE);
+		vbnv[HEADER_OFFSET] =
+		    (HEADER_SIGNATURE | HEADER_FIRMWARE_SETTINGS_RESET |
+		     HEADER_KERNEL_SETTINGS_RESET);
+	}
+	vbnv_initialized = 1;
+}
+
+int get_recovery_mode_from_vbnv(void)
+{
+	if (!vbnv_initialized)
+		vbnv_setup();
+	return vbnv[RECOVERY_OFFSET];
+}