mb/google/brya/var/marasov: Enable Wi-Fi sar table for Intel module

1.In contrast to the MediaTek Wi-Fi module, the Intel Wi-Fi module needs to load a SAR table.

2.Describe the FW_CONFIG probe for the settings on marasov.
- WIFI_SAR_ID_0 for MTK Wi-Fi module MT7921L
- WIFI_SAR_ID_1 for Intel Wi-Fi module AX211NGW

BUG=b:300045956
BRANCH=firmware-brya-14505.B
TEST=emerge-brya coreboot chromeos-bootimage

Change-Id: I5b5c6bea6c2c916fb682044218ec7b3a5d2659f6
Signed-off-by: Daniel Peng <Daniel_Peng@pegatron.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77789
Reviewed-by: Daniel Peng <daniel_peng@pegatron.corp-partner.google.com>
Reviewed-by: Eric Lai <ericllai@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>

src/mainboard/google/brya/Kconfig

@@ -269,6 +269,7 @@ config BOARD_GOOGLE_LISBON
 
 config BOARD_GOOGLE_MARASOV
 	select BOARD_GOOGLE_BASEBOARD_BRYA
+	select CHROMEOS_WIFI_SAR if CHROMEOS
 	select DRIVERS_INTEL_ISH
 	select SOC_INTEL_RAPTORLAKE
 	select USE_UNIFIED_AP_FIRMWARE_FOR_UFS_AND_NON_UFS

src/mainboard/google/brya/variants/marasov/overridetree.cb

@@ -16,6 +16,10 @@ fw_config
 		option TOUCH_NONE			0
 		option TOUCH_ELAN0001			1
 	end
+	field WIFI_SAR_ID 6 7
+		option WIFI_SAR_ID_0			0
+		option WIFI_SAR_ID_1			1
+	end
 	field STORAGE 30 31
 		option STORAGE_UNKNOWN			0
 		option STORAGE_NVME			1

src/mainboard/google/brya/variants/marasov/variant.c

@@ -2,8 +2,22 @@
 
 #include <acpi/acpigen.h>
 #include <baseboard/variants.h>
+#include <console/console.h>
+#include <fw_config.h>
+#include <sar.h>
 #include <variant/gpio.h>
 
+const char *get_wifi_sar_cbfs_filename(void)
+{
+	if (fw_config_probe(FW_CONFIG(WIFI_SAR_ID, WIFI_SAR_ID_1))) {
+		printk(BIOS_INFO, "Use wifi_sar_1.hex for Intel Wi-Fi module AX211NGW.\n");
+		return "wifi_sar_1.hex";
+	}
+
+	printk(BIOS_INFO, "Intel Wi-Fi SAR not used, return NULL!\n");
+	return NULL;
+}
+
 void variant_generate_s0ix_hook(enum s0ix_entry entry)
 {
 	/* Add board-specific MS0X entries */