From 5fd46f45987124b91fd3ce236bf524c1d28eb8b6 Mon Sep 17 00:00:00 2001
From: Peter Johanson <peter@peterjohanson.com>
Date: Wed, 9 Jul 2025 00:58:31 -0600
Subject: [PATCH] fix(boards): Retore bootloader support on XIAO BLE.

Set up necessary boot mode/retention to properly set GPREGRET to trigger
Adafruit bootloader to run on the XIAO BLE.
---
 app/boards/xiao_ble.conf    |  7 ++++++-
 app/boards/xiao_ble.overlay | 23 +++++++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/app/boards/xiao_ble.conf b/app/boards/xiao_ble.conf
index 205f67e91..49eaacf65 100644
--- a/app/boards/xiao_ble.conf
+++ b/app/boards/xiao_ble.conf
@@ -12,4 +12,9 @@ CONFIG_NVS=y
 CONFIG_SETTINGS_NVS=y
 CONFIG_FLASH=y
 CONFIG_FLASH_PAGE_LAYOUT=y
-CONFIG_FLASH_MAP=y
\ No newline at end of file
+CONFIG_FLASH_MAP=y
+
+CONFIG_RETAINED_MEM=y
+CONFIG_RETENTION=y
+CONFIG_RETENTION_BOOT_MODE=y
+CONFIG_ZMK_BOOTMODE_MAGIC_VALUE_BOOTLOADER_TYPE_ADAFRUIT_NRF52=y
diff --git a/app/boards/xiao_ble.overlay b/app/boards/xiao_ble.overlay
index 3b7710ef6..328b2717c 100644
--- a/app/boards/xiao_ble.overlay
+++ b/app/boards/xiao_ble.overlay
@@ -4,10 +4,33 @@
  * SPDX-License-Identifier: MIT
  */
 
+&gpregret1 {
+    adafruit_boot_retention: retention@0 {
+        compatible = "zephyr,retention";
+        status = "okay";
+        reg = <0x0 0x1>;
+    };
+};
 
 / {
     chosen {
         zmk,battery = &vbatt;
+        zephyr,boot-mode = &boot_retention;
+        zmk,magic-boot-mode = &adafruit_boot_retention;
+    };
+
+    magic_mapper {
+        compatible = "zmk,bootmode-to-magic-mapper";
+        status = "okay";
+
+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        boot_retention: retention@0 {
+            compatible = "zephyr,retention";
+            status = "okay";
+            reg = <0x0 0x1>;
+        };
     };
 
     vbatt: vbatt {