From 900875c6036ec91c2ecd9f03bf3295fb297d64b6 Mon Sep 17 00:00:00 2001
From: Francisco Molina <femolina@uc.cl>
Date: Mon, 2 Sep 2019 14:12:14 +0200
Subject: [PATCH 1/2] dist/tools/openocd: add OPENOCD_EXTRA_INIT_RESET

- Add a variable to add extra openocd commands before resetting
  a board. These will not be called when `debug`, in contrast
  to OPENOCD_CONFIG, OPENOCD_EXTRA_INIT and OPENOCD_ADAPTER_INIT.
- Add connect_assert_srst to reset config if
  OPENOCD_RESET_USE_CONNECT_ASSERT_SRST=1
---
 dist/tools/openocd/openocd.sh | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/dist/tools/openocd/openocd.sh b/dist/tools/openocd/openocd.sh
index 41b5adacb1..1e41add8e5 100755
--- a/dist/tools/openocd/openocd.sh
+++ b/dist/tools/openocd/openocd.sh
@@ -73,6 +73,8 @@
 : ${OPENOCD_EXTRA_INIT:=}
 # Debugger interface initialization commands to pass to OpenOCD
 : ${OPENOCD_ADAPTER_INIT:=}
+# If set to 1 'reset_config' will use 'connect_assert_srst' before 'flash' or 'reset.
+: ${OPENOCD_RESET_USE_CONNECT_ASSERT_SRST:=}
 # The setsid command is needed so that Ctrl+C in GDB doesn't kill OpenOCD
 : ${SETSID:=setsid}
 # GDB command, usually a separate command for each platform (e.g. arm-none-eabi-gdb)
@@ -106,7 +108,6 @@
 #
 # Examples of alternative debugger configurations
 #
-
 # Using the GDB text UI:
 # DBG_EXTRA_FLAGS=-tui make debug
 # or to always use TUI, put in your .profile:
@@ -119,6 +120,11 @@
 # export DBG_FLAGS='--debugger "${GDB} ${DBG_DEFAULT_FLAGS}"'
 # The single quotes are important on the line above, or it will not work.
 
+# Handle OPENOCD_RESET_USE_CONNECT_ASSERT_SRST
+if [ "${OPENOCD_RESET_USE_CONNECT_ASSERT_SRST}" -eq 1 ]; then
+  OPENOCD_EXTRA_RESET_INIT+="-c 'reset_config connect_assert_srst'"
+fi
+
 #
 # a couple of tests for certain configuration options
 #
@@ -205,6 +211,7 @@ _flash_list_raw() {
     sh -c "${OPENOCD} \
             ${OPENOCD_ADAPTER_INIT} \
             -f '${OPENOCD_CONFIG}' \
+            ${OPENOCD_EXTRA_RESET_INIT} \
             -c 'init' \
             -c 'flash probe 0' \
             -c 'flash list' \
@@ -274,6 +281,7 @@ do_flash() {
             ${OPENOCD_ADAPTER_INIT} \
             -f '${OPENOCD_CONFIG}' \
             ${OPENOCD_EXTRA_INIT} \
+            ${OPENOCD_EXTRA_RESET_INIT} \
             -c 'tcl_port 0' \
             -c 'telnet_port 0' \
             -c 'gdb_port 0' \
@@ -353,6 +361,7 @@ do_reset() {
             ${OPENOCD_ADAPTER_INIT} \
             -f '${OPENOCD_CONFIG}' \
             ${OPENOCD_EXTRA_INIT} \
+            ${OPENOCD_EXTRA_RESET_INIT} \
             -c 'tcl_port 0' \
             -c 'telnet_port 0' \
             -c 'gdb_port 0' \

From 06c830e8cda61e4f25f2dd2ff692be972726f087 Mon Sep 17 00:00:00 2001
From: Francisco Molina <femolina@uc.cl>
Date: Mon, 2 Sep 2019 14:16:04 +0200
Subject: [PATCH 2/2] boards/nucleo-f091rc: set
 OPENOCD_RESET_USE_CONNECT_ASSERT_SRST

- Nucleo-f091rc can become unflashable when hardfaults occure.
  To make sure flashing succeeds `connect_assert_srst` is called
  before connecting to flash threw openocd.
---
 boards/nucleo-f091rc/Makefile.include | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/boards/nucleo-f091rc/Makefile.include b/boards/nucleo-f091rc/Makefile.include
index 8db8eaed90..d01fb044ac 100644
--- a/boards/nucleo-f091rc/Makefile.include
+++ b/boards/nucleo-f091rc/Makefile.include
@@ -1,2 +1,6 @@
+# nucleo-f091rc can become un-flashable after a hardfault, use connect_assert_srst
+# to always be able to flash or reset the board.
+export OPENOCD_RESET_USE_CONNECT_ASSERT_SRST ?= 1
+
 # load the common Makefile.include for Nucleo boards
 include $(RIOTBOARD)/common/nucleo64/Makefile.include