mb/google/dragonegg: Add initial mainboard code support

This patch includes support for both ICL ES0 and ES1 samples.

Detailed document is here: Documentation/soc/intel/icelake/iceLake_coreboot_development.md

TEST=Able to build and boot dragonegg.

Change-Id: I2cc269cb0050bf5b031f48cfe114485c55ab8fa9
Signed-off-by: Aamir Bohra <aamir.bohra@intel.com>
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/c/29749
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/mainboard/google/dragonegg/chromeos.c

@@ -0,0 +1,56 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 Intel Corporation.
+ *
+ * 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 <arch/acpi.h>
+#include <baseboard/variants.h>
+#include <gpio.h>
+#include <rules.h>
+#include <soc/gpio.h>
+#include <vendorcode/google/chromeos/chromeos.h>
+
+#include <variant/gpio.h>
+
+#if ENV_RAMSTAGE
+#include <boot/coreboot_tables.h>
+
+void fill_lb_gpios(struct lb_gpios *gpios)
+{
+	struct lb_gpio chromeos_gpios[] = {
+		{-1, ACTIVE_HIGH, get_write_protect_state(), "write protect"},
+		{-1, ACTIVE_HIGH, get_recovery_mode_switch(), "recovery"},
+		{-1, ACTIVE_HIGH, get_lid_switch(), "lid"},
+		{-1, ACTIVE_HIGH, 0, "power"},
+		{-1, ACTIVE_HIGH, gfx_get_init_done(), "oprom"},
+		{GPIO_EC_IN_RW, ACTIVE_HIGH, gpio_get(GPIO_EC_IN_RW),
+		 "EC in RW"},
+	};
+	lb_add_gpios(gpios, chromeos_gpios, ARRAY_SIZE(chromeos_gpios));
+}
+#endif /* ENV_RAMSTAGE */
+
+int get_write_protect_state(void)
+{
+	/* Read PCH_WP GPIO. */
+	return gpio_get(GPIO_PCH_WP);
+}
+
+void mainboard_chromeos_acpi_generate(void)
+{
+	const struct cros_gpio *gpios;
+	size_t num;
+
+	gpios = variant_cros_gpios(&num);
+	chromeos_acpi_gpio_generate(gpios, num);
+}