From 26751c76f2e4c8faa28492026f4777963c9879d3 Mon Sep 17 00:00:00 2001
From: liquidraver <504870+liquidraver@users.noreply.github.com>
Date: Fri, 18 Sep 2026 21:40:41 +0200
Subject: [PATCH] cherry pick openocd patch from zephyr main

---
 .../seeed_lr2021_evk/support/openocd.cfg      |  5 +++
 ...rd-xiao-nrf54l15-openocd-rram-commit.patch | 33 +++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 zephcore/patches/zephyr/0016-board-xiao-nrf54l15-openocd-rram-commit.patch

diff --git a/zephcore/boards/nrf54l/seeed_lr2021_evk/support/openocd.cfg b/zephcore/boards/nrf54l/seeed_lr2021_evk/support/openocd.cfg
index 8ec6b49..cc90c5f 100644
--- a/zephcore/boards/nrf54l/seeed_lr2021_evk/support/openocd.cfg
+++ b/zephcore/boards/nrf54l/seeed_lr2021_evk/support/openocd.cfg
@@ -66,6 +66,11 @@ if {![using_hla]} {
 proc nrf54l-load {file} {
 	mww 0x5004b500 0x101
 	load_image $file
+	# Commit the final partial 128-bit RRAM write line left by load_image.
+	# RRAMC.TASKS_COMMITWRITEBUF @ 0x5004b008. Mirrors upstream 1079b21dcda7
+	# (see patches/zephyr/0016); without it the image's last line keeps the
+	# previous firmware's bytes.
+	mww 0x5004b008 1
 }
 
 # Define CTRL_AP_NUM explicitly to avoid variable errors
diff --git a/zephcore/patches/zephyr/0016-board-xiao-nrf54l15-openocd-rram-commit.patch b/zephcore/patches/zephyr/0016-board-xiao-nrf54l15-openocd-rram-commit.patch
new file mode 100644
index 0000000..b9e6d7e
--- /dev/null
+++ b/zephcore/patches/zephyr/0016-board-xiao-nrf54l15-openocd-rram-commit.patch
@@ -0,0 +1,33 @@
+ZephCore: backport of upstream zephyrproject-rtos/zephyr 1079b21dcda7
+("boards: seeed: commit RRAM write buffer after image load", PR #117961,
+merged to main 2026-09-01). Not on v4.4-branch, and no backport requested.
+
+The board's `nrf54l-load` proc enables RRAMC writes with a one-line
+(128-bit) write buffer and calls load_image, but never commits the buffer.
+The image's final partial line is lost at reset, so those bytes keep
+whatever the previously flashed firmware had there. Symptom depends on what
+lands in that line: in the XIAO nRF54L15 battery-ADC build it was the
+startup value of `sync_evt_pool.__bufs`, and flashing that image over a
+debug build bus-faulted at the first BT HCI allocation (BFAR 0xf7ce720d,
+the debug image's bytes). Erasing does not help; the lost line then reads
+0xFF. Reproduced and fix verified on hardware 2026-09-18.
+
+DROP THIS PATCH once the Zephyr pin contains 1079b21dcda7 (or upstream's
+later refactor ca77b788f93a, which moves the proc to
+boards/seeed/common/openocd_nrf54l.cfg as `nrf54l_load`). It will then fail
+`git apply --check`, which is fatal at configure time.
+
+diff --git a/boards/seeed/xiao_nrf54l15/support/openocd.cfg b/boards/seeed/xiao_nrf54l15/support/openocd.cfg
+index 8ec6b496f65a..c0e227ff342e 100644
+--- a/boards/seeed/xiao_nrf54l15/support/openocd.cfg
++++ b/boards/seeed/xiao_nrf54l15/support/openocd.cfg
+@@ -66,6 +66,9 @@ if {![using_hla]} {
+ proc nrf54l-load {file} {
+ 	mww 0x5004b500 0x101
+ 	load_image $file
++	# Commit the final partial 128-bit RRAM write line left by load_image.
++	# RRAMC.TASKS_COMMITWRITEBUF @ 0x5004b008.
++	mww 0x5004b008 1
+ }
+ 
+ # Define CTRL_AP_NUM explicitly to avoid variable errors