mb/google/kahlee: Add SKU support

We want to report the board SKU via the SMBIOS tables. Add support for
this, obtaining the ID itself from the EC.

BUG=b:74175244
BRANCH=none
TEST=manually on grunt with another CL:
mosys platform sku
0

Change-Id: I9e08d64df3f89d3703de047dd9ec8e1717e6b212
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-on: https://review.coreboot.org/25011
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

src/mainboard/google/kahlee/mainboard.c

@@ -13,6 +13,7 @@
  * GNU General Public License for more details.
  */
 
+#include <string.h>
 #include <console/console.h>
 #include <device/device.h>
 #include <arch/acpi.h>
@@ -21,6 +22,7 @@
 #include <cbmem.h>
 #include <baseboard/variants.h>
 #include <boardid.h>
+#include <smbios.h>
 #include <soc/nvs.h>
 #include <soc/pci_devs.h>
 #include <soc/smi.h>
@@ -221,3 +223,18 @@ struct chip_operations mainboard_ops = {
 	.enable_dev = kahlee_enable,
 	.final = mainboard_final,
 };
+
+/* Variants may override this function so see definitions in variants/ */
+uint8_t __attribute__((weak)) variant_board_sku(void)
+{
+	return 0;
+}
+
+const char *smbios_mainboard_sku(void)
+{
+	static char sku_str[7]; /* sku{0..255} */
+
+	snprintf(sku_str, sizeof(sku_str), "sku%d", variant_board_sku());
+
+	return sku_str;
+}

src/mainboard/google/kahlee/variants/baseboard/include/baseboard/variants.h

@@ -24,6 +24,8 @@
 
 const struct sci_source *get_gpe_table(size_t *num);
 uint8_t variant_memory_sku(void);
+/* Return board SKU. Limited to uint8_t, so it fits into 3 decimal digits */
+uint8_t variant_board_sku(void);
 int variant_mainboard_read_spd(uint8_t spdAddress, char *buf, size_t len);
 int variant_get_xhci_oc_map(uint16_t *usb_oc_map);
 int variant_get_ehci_oc_map(uint16_t *usb_oc_map);

src/mainboard/google/kahlee/variants/grunt/Makefile.inc

@@ -14,3 +14,5 @@
 #
 
 subdirs-y += spd
+
+ramstage-y += mainboard.c

src/mainboard/google/kahlee/variants/grunt/mainboard.c

@@ -0,0 +1,27 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 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 <ec/google/chromeec/ec.h>
+#include <baseboard/variants.h>
+
+uint8_t variant_board_sku(void)
+{
+	static int sku = -1;
+
+	if (sku == -1)
+		sku = google_chromeec_get_sku_id();
+
+	return sku;
+}