ec/lenovo/h8: Add VBOOT board support

Use Fn-Key as recovery mode switch.

Tested using Icb7b263ed86551cc53e1db7babccaca6b3ae2fe6.

Change-Id: I2c682431b3f09839db265259205104bd9ef4abfc
Signed-off-by: Patrick Rudolph <siro@das-labor.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32607
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>

src/ec/lenovo/h8/Kconfig

@@ -32,6 +32,14 @@ config H8_HAS_BAT_TRESHOLDS_IMPL
 	bool
 	default n
 
+config H8_FN_KEY_AS_VBOOT_RECOVERY_SW
+	bool "Enable Fn-Key as VBOOT recovery switch"
+	depends on VBOOT
+	default n
+	help
+	  If VBOOT is enabled, press Fn-Key at power on to force a recovery mode
+	  boot instead of regular FW_MAIN_x boot.
+
 endif
 
 config H8_DOCK_EARLY_INIT

src/ec/lenovo/h8/Makefile.inc

@@ -7,6 +7,12 @@ bootblock-y += sense.c
 postcar-y += sense.c
 smm-y += sense.c
 
+ramstage-$(CONFIG_VBOOT) += vboot.c
+verstage-$(CONFIG_VBOOT) += vboot.c
+romstage-$(CONFIG_VBOOT) += vboot.c
+bootblock-$(CONFIG_VBOOT) += vboot.c
+postcar-$(CONFIG_VBOOT) += vboot.c
+
 ifneq ($(filter y,$(CONFIG_H8_BEEP_ON_DEATH) $(CONFIG_H8_FLASH_LEDS_ON_DEATH)),)
 romstage-y += panic.c
 ramstage-y += panic.c

src/ec/lenovo/h8/vboot.c

@@ -0,0 +1,55 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 Patrick Rudolph <siro@das-labor.org>
+ *
+ * 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 <ec/acpi/ec.h>
+#include <bootmode.h>
+#include <timer.h>
+#include <delay.h>
+
+#include "h8.h"
+
+/**
+ * HACK: Use Fn-Key as recovery mode switch.
+ * Wait for sense register ready and read Fn-Key state.
+ */
+int get_recovery_mode_switch(void)
+{
+	struct stopwatch sw;
+
+	if (!CONFIG(H8_FN_KEY_AS_VBOOT_RECOVERY_SW))
+		return 0;
+
+	/* Tests showed that it takes:
+	 *  - 700msec on Lenovo T500 from AC power on
+	 *  - less than 150msec on Lenovo T520 from AC power on
+	 */
+	stopwatch_init_msecs_expire(&sw, 1000);
+	while (!stopwatch_expired(&sw) && !h8_get_sense_ready())
+		mdelay(1);
+
+	if (!h8_get_sense_ready())
+		return 0;
+
+	return h8_get_fn_key();
+}
+
+/**
+ * Only used if CONFIG_CHROMEOS is set.
+ * Always zero as the #WP pin of the flash is tied high.
+ */
+int get_write_protect_state(void)
+{
+	return 0;
+}