dist/tools/openocd/openocd.sh: add FLASH_BANK

Allow specifying index of `flash bank` to read configuration from
in cases where the configuration provided in openocd is incorrect.

This is the case for the majority of stm32 boards where it relies
on `flash probe` to get the correct value.

dist/tools/openocd/openocd.sh

@@ -105,6 +105,10 @@
 # Valid values: elf, hex, s19, bin (see OpenOCD manual for more information)
 : ${IMAGE_TYPE:=}
 
+# flash bank to read default configuration when probing fails, default to first
+# bank
+: ${FLASH_BANK:=1}
+
 #
 # Examples of alternative debugger configurations
 #
@@ -265,8 +269,7 @@ do_flash() {
     # In case of binary file, IMAGE_OFFSET should include the flash base address
     # This allows flashing normal binary files without env configuration
     if _is_binfile "${IMAGE_FILE}" "${IMAGE_TYPE}"; then
-        # hardwritten to use the first bank
-        FLASH_ADDR=$(_flash_address 1)
+        FLASH_ADDR=$(_flash_address ${FLASH_BANK})
         echo "Binfile detected, adding ROM base address: ${FLASH_ADDR}"
         IMAGE_TYPE=bin
         IMAGE_OFFSET=$(printf "0x%08x\n" "$((${IMAGE_OFFSET} + ${FLASH_ADDR}))")