google/enguarde: Upstream Lenovo N21 Chromebook

Migrate google/enguarde (Lenovo N21 Chromebook) from Chromium tree to
upstream, using google/rambi as a reference.

original source:
branch firmware-enguarde-5216.201.B
commit cf1f57b [Enguarde: Adjust rx delay for norm.]

TEST=built and booted Linux on enguarde with full functionality

blobs required for working image:
VGA BIOS (vgabios.bin)
firmware descriptor (ifd.bin)
Intel ME firmware (me.bin)
MRC (mrc.elf)
external reference code (refcode.elf)

Change-Id: I3ccda29d1e095d8b1b36766cda913172f72233a7
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/15444
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

1 files changed, 112 insertions, 0 deletions

diff --git a/src/mainboard/google/enguarde/chromeos.c b/src/mainboard/google/enguarde/chromeos.c
new file mode 100644
index 0000000000..c8a33c4f97
--- /dev/null
+++ b/src/mainboard/google/enguarde/chromeos.c
@@ -0,0 +1,112 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 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 <string.h>
+#include <bootmode.h>
+#include <arch/io.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <soc/gpio.h>
+
+#if CONFIG_EC_GOOGLE_CHROMEEC
+#include "ec.h"
+#include <ec/google/chromeec/ec.h>
+#endif
+
+/* The WP status pin lives on GPIO_SSUS_6 which is pad 36 in the SUS well. */
+#define WP_STATUS_PAD	36
+
+#ifndef __PRE_RAM__
+#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, recovery_mode_enabled(), "recovery"},
+		{-1, ACTIVE_HIGH, get_developer_mode_switch(), "developer"},
+		{-1, ACTIVE_HIGH, get_lid_switch(), "lid"},
+		{-1, ACTIVE_HIGH, 0, "power"},
+		{-1, ACTIVE_HIGH, gfx_get_init_done(), "oprom"},
+	};
+	lb_add_gpios(gpios, chromeos_gpios, ARRAY_SIZE(chromeos_gpios));
+}
+#endif
+
+int get_lid_switch(void)
+{
+#if CONFIG_EC_GOOGLE_CHROMEEC
+	u8 ec_switches = inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SWITCHES);
+
+	return !!(ec_switches & EC_SWITCH_LID_OPEN);
+#else
+	/* Default to force open. */
+	return 1;
+#endif
+}
+
+int get_developer_mode_switch(void)
+{
+	return 0;
+}
+
+int get_recovery_mode_switch(void)
+{
+#if CONFIG_EC_GOOGLE_CHROMEEC
+	u8 ec_switches = inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SWITCHES);
+	u32 ec_events;
+
+	/* If a switch is set, we don't need to look at events. */
+	if (ec_switches & (EC_SWITCH_DEDICATED_RECOVERY))
+		return 1;
+
+	/* Else check if the EC has posted the keyboard recovery event. */
+	ec_events = google_chromeec_get_events_b();
+
+	return !!(ec_events &
+		  EC_HOST_EVENT_MASK(EC_HOST_EVENT_KEYBOARD_RECOVERY));
+#else
+	return 0;
+#endif
+}
+
+int clear_recovery_mode_switch(void)
+{
+#if CONFIG_EC_GOOGLE_CHROMEEC
+	const uint32_t kb_rec_mask =
+		EC_HOST_EVENT_MASK(EC_HOST_EVENT_KEYBOARD_RECOVERY);
+	/* Unconditionally clear the EC recovery request. */
+	return google_chromeec_clear_events_b(kb_rec_mask);
+#else
+	return 0;
+#endif
+}
+
+int get_write_protect_state(void)
+{
+	/*
+	 * The vboot loader queries this function in romstage. The GPIOs have
+	 * not been set up yet as that configuration is done in ramstage. The
+	 * hardware defaults to an input but there is a 20K pulldown. Externally
+	 * there is a 10K pullup. Disable the internal pull in romstage so that
+	 * there isn't any ambiguity in the reading.
+	 */
+#if defined(__PRE_RAM__)
+	ssus_disable_internal_pull(WP_STATUS_PAD);
+#endif
+
+	/* WP is enabled when the pin is reading high. */
+	return ssus_get_gpio(WP_STATUS_PAD);
+}