cr50: check if the new image needs to be enabled and act on it

The AP sends the Cr50 a request to enable the new firmware image. If
the new Cr50 image was found and enabled, the AP expects the Cr50 to
reset the device in 1 second.

While waiting for the Cr50 to reset, the AP logs a newly defined event
and optionally shuts down the system. By default the x86 systems power
off as shutting those systems down is not board specific.

BRANCH=gru,reef
BUG=b:35580805
TEST=built a reef image, observed that in case cr50 image is updated,
     after the next reboot the AP stops booting before loading depthcharge,
     reports upcoming reset and waits for it.

     Once the system is booted after that, the new event can be found
     in the log:

  localhost ~ # mosys eventlog list
  ...
  7 | 2017-03-23 18:42:12 | Chrome OS Developer Mode
  8 | 2017-03-23 18:42:13 | Unknown | 0xac
  9 | 2017-03-23 18:42:21 | System boot | 46
  ...

Change-Id: I45fd6058c03f32ff8edccd56ca2aa5359d9b21b1
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/18946
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/Kconfig

@@ -406,11 +406,17 @@ config TPM2
 
 	  If unsure, say N.
 
+config POWER_OFF_ON_CR50_UPDATE
+	bool
+	help
+	  Power off machine while waiting for CR50 update to take effect.
+
 config MAINBOARD_HAS_TPM_CR50
 	bool
 	default y if MAINBOARD_HAS_SPI_TPM_CR50 || MAINBOARD_HAS_I2C_TPM_CR50
 	default n
 	select MAINBOARD_HAS_TPM2
+	select POWER_OFF_ON_CR50_UPDATE if ARCH_X86
 
 config HEAP_SIZE
 	hex

src/include/elog.h

@@ -122,6 +122,7 @@
 #define  ELOG_WAKE_SOURCE_GPIO             0x04
 #define  ELOG_WAKE_SOURCE_SMBUS            0x05
 #define  ELOG_WAKE_SOURCE_PWRBTN           0x06
+
 struct elog_event_data_wake {
 	u8 source;
 	u32 instance;
@@ -174,6 +175,9 @@ struct elog_event_mem_cache_update {
 /* CPU Thermal Trip */
 #define ELOG_TYPE_THERM_TRIP              0xab
 
+/* Cr50 */
+#define ELOG_TYPE_CR50_UPDATE             0xac
+
 #if CONFIG_ELOG
 /* Eventlog backing storage must be initialized before calling elog_init(). */
 extern int elog_init(void);

src/vendorcode/google/chromeos/Makefile.inc

@@ -22,6 +22,7 @@ ramstage-y += vpd_decode.c cros_vpd.c vpd_mac.c vpd_serialno.c vpd_calibration.c
 ramstage-$(CONFIG_CHROMEOS_DISABLE_PLATFORM_HIERARCHY_ON_RESUME) += tpm2.c
 ramstage-$(CONFIG_HAVE_REGULATORY_DOMAIN) += wrdd.c
 ramstage-$(CONFIG_USE_SAR) += sar.c
+ramstage-$(CONFIG_MAINBOARD_HAS_TPM_CR50) += cr50_enable_update.c
 ifeq ($(CONFIG_ARCH_MIPS),)
 bootblock-y += watchdog.c
 ramstage-y += watchdog.c

src/vendorcode/google/chromeos/cr50_enable_update.c

@@ -0,0 +1,71 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2017 Google Inc.
+ *
+ * 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 <bootstate.h>
+#include <console/console.h>
+#include <ec/google/chromeec/ec.h>
+#include <elog.h>
+#include <halt.h>
+#include <tpm_lite/tlcl.h>
+#include <vb2_api.h>
+#include <vboot/vboot_common.h>
+
+static void enable_update(void *unused)
+{
+	int ret;
+	uint8_t num_restored_headers;
+
+	/* Nothing to do on recovery mode. */
+	if (vboot_recovery_mode_enabled())
+		return;
+
+	ret = tlcl_lib_init();
+
+	if (ret != VB2_SUCCESS) {
+		printk(BIOS_ERR, "tlcl_lib_init() failed for CR50 update: %x\n",
+			ret);
+		return;
+	}
+
+	/* Reboot in 1000 ms if necessary. */
+	ret = tlcl_cr50_enable_update(1000, &num_restored_headers);
+
+	if (ret != TPM_SUCCESS) {
+		printk(BIOS_ERR, "Attempt to enable CR50 update failed: %x\n",
+			ret);
+		return;
+	}
+
+	/* If no headers were restored there is no reset forthcoming. */
+	if (!num_restored_headers)
+		return;
+
+	elog_add_event(ELOG_TYPE_CR50_UPDATE);
+
+	/* clear current post code avoid chatty eventlog on subsequent boot*/
+	post_code(0);
+
+	printk(BIOS_INFO, "Waiting for CR50 reset to pick up update.\n");
+
+	if (IS_ENABLED(CONFIG_POWER_OFF_ON_CR50_UPDATE)) {
+		if (IS_ENABLED(CONFIG_EC_GOOGLE_CHROMEEC))
+			google_chromeec_reboot(0, EC_REBOOT_HIBERNATE,
+				EC_REBOOT_FLAG_ON_AP_SHUTDOWN);
+		poweroff();
+	}
+	halt();
+}
+BOOT_STATE_INIT_ENTRY(BS_PAYLOAD_LOAD, BS_ON_ENTRY, enable_update, NULL);
+