rockchip: odroid-go2: Select board FDT from FIT in SPL

Include FDTs for all three board variants in the FIT image and adjust
the board selection code to use correct FDT in U-Boot proper.

E.g. use the odroid-go3 DT for a ODROID-GO Super device:

  U-Boot 2025.07 (Jul 13 2025 - 10:07:16 +0000)

  Model: ODROID-GO Super
  DRAM:  1 GiB (total 1022 MiB)
  PMIC:  RK817 (on=0x80, off=0x08)

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>

arch/arm/dts/rk3326-odroid-go2-u-boot.dtsi

@@ -39,7 +39,8 @@
 };
 
 &saradc {
-	bootph-all;
+	bootph-pre-ram;
+	vdd-microvolts = <1800000>;
 };
 
 &sfc {

arch/arm/dts/rk3326-odroid-go2-v11-u-boot.dtsi

@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+#include "rk3326-odroid-go2-u-boot.dtsi"

arch/arm/dts/rk3326-odroid-go3-u-boot.dtsi

@@ -0,0 +1,3 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+#include "rk3326-odroid-go2-u-boot.dtsi"

board/hardkernel/odroid_go2/Kconfig

@@ -9,4 +9,10 @@ config SYS_VENDOR
 config SYS_CONFIG_NAME
 	default "odroid_go2"
 
+config BOARD_SPECIFIC_OPTIONS # dummy
+	def_bool y
+	select ADC
+	select BOARD_TYPES
+	select SPL_ADC
+
 endif

board/hardkernel/odroid_go2/go2.c

@@ -10,6 +10,8 @@
 #include <env.h>
 #include <stdlib.h>
 
+DECLARE_GLOBAL_DATA_PTR;
+
 #define DTB_DIR			"rockchip/"
 
 struct oga_model {
@@ -20,7 +22,7 @@ struct oga_model {
 };
 
 enum oga_device_id {
-	OGA,
+	OGA = 1,
 	OGA_V11,
 	OGS,
 };
@@ -50,15 +52,10 @@ static const struct oga_model oga_model_details[] = {
 	},
 };
 
-/* Detect which Odroid Go Advance device we are using so as to load the
- * correct devicetree for Linux. Set an environment variable once
- * found. The detection depends on the value of ADC channel 0.
- */
-int oga_detect_device(void)
+static int oga_read_board_id(void)
 {
 	u32 adc_info;
-	int ret, i;
-	int board_id = -ENXIO;
+	int i, ret;
 
 	ret = adc_channel_single_shot("saradc@ff288000", 0, &adc_info);
 	if (ret) {
@@ -72,22 +69,32 @@ int oga_detect_device(void)
 	 * accounted for this with a 5% tolerance, so assume a +- value
 	 * of 50 should be enough.
 	 */
-	for (i = 0; i < ARRAY_SIZE(oga_model_details); i++) {
+	for (i = 1; i < ARRAY_SIZE(oga_model_details); i++) {
 		u32 adc_min = oga_model_details[i].adc_value - 50;
 		u32 adc_max = oga_model_details[i].adc_value + 50;
 
-		if (adc_min < adc_info && adc_max > adc_info) {
-			board_id = i;
-			break;
-		}
+		if (adc_min < adc_info && adc_max > adc_info)
+			return i;
 	}
 
+	return -ENODEV;
+}
+
+/* Detect which Odroid Go Advance device we are using so as to load the
+ * correct devicetree for Linux. Set an environment variable once
+ * found. The detection depends on the value of ADC channel 0.
+ */
+static int oga_detect_device(void)
+{
+	int board_id;
+
+	board_id = oga_read_board_id();
 	if (board_id < 0)
 		return board_id;
+	gd->board_type = board_id;
 
 	env_set("board", oga_model_details[board_id].board);
-	env_set("board_name",
-		oga_model_details[board_id].board_name);
+	env_set("board_name", oga_model_details[board_id].board_name);
 	env_set("fdtfile", oga_model_details[board_id].fdtfile);
 
 	return 0;
@@ -105,3 +112,20 @@ int rk_board_late_init(void)
 
 	return 0;
 }
+
+int board_fit_config_name_match(const char *name)
+{
+	int board_id;
+
+	if (!gd->board_type) {
+		board_id = oga_read_board_id();
+		if (board_id < 0)
+			return board_id;
+		gd->board_type = board_id;
+	}
+
+	if (!strcmp(name, oga_model_details[gd->board_type].fdtfile))
+		return 0;
+
+	return -EINVAL;
+}

configs/odroid-go2_defconfig

@@ -8,6 +8,7 @@ CONFIG_SF_DEFAULT_MODE=0x1000
 CONFIG_ENV_SIZE=0x4000
 CONFIG_ENV_OFFSET=0x4000
 CONFIG_DEFAULT_DEVICE_TREE="rockchip/rk3326-odroid-go2"
+CONFIG_OF_LIBFDT_OVERLAY=y
 CONFIG_DM_RESET=y
 CONFIG_ROCKCHIP_PX30=y
 CONFIG_ROCKCHIP_RK8XX_DISABLE_BOOT_ON_POWERON=y
@@ -61,6 +62,7 @@ CONFIG_CMD_USB_MASS_STORAGE=y
 CONFIG_EFI_PARTITION_ENTRIES_NUMBERS=64
 CONFIG_SPL_OF_CONTROL=y
 CONFIG_OF_LIVE=y
+CONFIG_OF_LIST="rockchip/rk3326-odroid-go2 rockchip/rk3326-odroid-go2-v11 rockchip/rk3326-odroid-go3"
 CONFIG_OF_SPL_REMOVE_PROPS="interrupt-parent assigned-clocks assigned-clock-rates assigned-clock-parents"
 CONFIG_ENV_IS_IN_MMC=y
 CONFIG_SPL_DM_SEQ_ALIAS=y