src/mainboard/kahlee: Turn on keyboard backlight on grunt

Turn on keyboard backlight in romstage to indicate that the system is
booting.

BUG=b:77921345
TEST=Boot grunt, keyboard backlight comes on.

Change-Id: Ib215b19ebdee2f8c4f431af775905eca42436d1c
Signed-off-by: Martin Roth <martinroth@chromium.org>
Reviewed-on: https://review.coreboot.org/25636
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/mainboard/google/kahlee/romstage.c b/src/mainboard/google/kahlee/romstage.c
index 8f234a3..4cd2d40 100644
--- a/src/mainboard/google/kahlee/romstage.c
+++ b/src/mainboard/google/kahlee/romstage.c
@@ -15,8 +15,19 @@
 
 #include <amdblocks/dimm_spd.h>
 #include <baseboard/variants.h>
+#include <soc/romstage.h>
 
 int mainboard_read_spd(uint8_t spdAddress, char *buf, size_t len)
 {
 	return variant_mainboard_read_spd(spdAddress, buf, len);
 }
+
+void __attribute__((weak)) variant_romstage_entry(int s3_resume)
+{
+	/* By default, don't do anything */
+}
+
+void mainboard_romstage_entry(int s3_resume)
+{
+	variant_romstage_entry(s3_resume);
+}
diff --git a/src/mainboard/google/kahlee/variants/baseboard/include/baseboard/variants.h b/src/mainboard/google/kahlee/variants/baseboard/include/baseboard/variants.h
index e5a348a..bc35ff5 100644
--- a/src/mainboard/google/kahlee/variants/baseboard/include/baseboard/variants.h
+++ b/src/mainboard/google/kahlee/variants/baseboard/include/baseboard/variants.h
@@ -31,5 +31,6 @@
 int variant_get_ehci_oc_map(uint16_t *usb_oc_map);
 const struct soc_amd_stoneyridge_gpio *variant_early_gpio_table(size_t *size);
 const struct soc_amd_stoneyridge_gpio *variant_gpio_table(size_t *size);
+void variant_romstage_entry(int s3_resume);
 
 #endif /* __BASEBOARD_VARIANTS_H__ */
diff --git a/src/mainboard/google/kahlee/variants/grunt/Makefile.inc b/src/mainboard/google/kahlee/variants/grunt/Makefile.inc
index 7a4b994..3ef10b3 100644
--- a/src/mainboard/google/kahlee/variants/grunt/Makefile.inc
+++ b/src/mainboard/google/kahlee/variants/grunt/Makefile.inc
@@ -15,4 +15,6 @@
 
 subdirs-y += spd
 
+romstage-y += romstage.c
+
 ramstage-y += mainboard.c
diff --git a/src/mainboard/google/kahlee/variants/grunt/romstage.c b/src/mainboard/google/kahlee/variants/grunt/romstage.c
new file mode 100644
index 0000000..2b8baf8
--- /dev/null
+++ b/src/mainboard/google/kahlee/variants/grunt/romstage.c
@@ -0,0 +1,26 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2018 Google, LLC.
+ *
+ * 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 <baseboard/variants.h>
+#include <ec/google/chromeec/ec.h>
+
+void variant_romstage_entry(int s3_resume)
+{
+	uint32_t sku = google_chromeec_get_sku_id();
+
+	/* Based on SKU, turn on keyboard backlight to show system is booting */
+	if (sku <= 6 && !s3_resume)
+		google_chromeec_kbbacklight(75);
+}