From b26046aca2f2abb357f454974f69bc4fa8e4afab Mon Sep 17 00:00:00 2001
From: Damien George <damien.p.george@gmail.com>
Date: Thu, 7 Feb 2019 16:13:57 +1100
Subject: [PATCH] stm32/modmachine: Make bootloader() enter custom loader if
 it's enabled.

If a custom bootloader is enabled (eg mboot) then machine.bootloader() will
now enter that loader.  To get the original ST DFU loader pass any argument
to the function, like machine.bootloader(1).
---
 ports/stm32/modmachine.c | 16 ++++++++++++++--
 ports/stm32/modmachine.h |  2 +-
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/ports/stm32/modmachine.c b/ports/stm32/modmachine.c
index e14753bfe9..3c60378ffd 100644
--- a/ports/stm32/modmachine.c
+++ b/ports/stm32/modmachine.c
@@ -247,7 +247,7 @@ STATIC mp_obj_t machine_soft_reset(void) {
 MP_DEFINE_CONST_FUN_OBJ_0(machine_soft_reset_obj, machine_soft_reset);
 
 // Activate the bootloader without BOOT* pins.
-STATIC NORETURN mp_obj_t machine_bootloader(void) {
+STATIC NORETURN mp_obj_t machine_bootloader(size_t n_args, const mp_obj_t *args) {
     #if MICROPY_HW_ENABLE_USB
     pyb_usb_dev_deinit();
     #endif
@@ -263,6 +263,18 @@ STATIC NORETURN mp_obj_t machine_bootloader(void) {
     HAL_MPU_Disable();
     #endif
 
+    #if MICROPY_HW_USES_BOOTLOADER
+    if (n_args == 0 || !mp_obj_is_true(args[0])) {
+        // By default, with no args given, we enter the custom bootloader (mboot)
+        #if __DCACHE_PRESENT == 1
+        SCB_DisableICache();
+        SCB_DisableDCache();
+        #endif
+        __set_MSP(*(volatile uint32_t*)0x08000000);
+        ((void (*)(uint32_t)) *((volatile uint32_t*)(0x08000000 + 4)))(0x70ad0000);
+    }
+    #endif
+
 #if defined(STM32F7) || defined(STM32H7)
     // arm-none-eabi-gcc 4.9.0 does not correctly inline this
     // MSP function, so we write it out explicitly here.
@@ -283,7 +295,7 @@ STATIC NORETURN mp_obj_t machine_bootloader(void) {
 
     while (1);
 }
-MP_DEFINE_CONST_FUN_OBJ_0(machine_bootloader_obj, machine_bootloader);
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(machine_bootloader_obj, 0, 1, machine_bootloader);
 
 // get or set the MCU frequencies
 STATIC mp_obj_t machine_freq(size_t n_args, const mp_obj_t *args) {
diff --git a/ports/stm32/modmachine.h b/ports/stm32/modmachine.h
index f105bbeec3..414e5b37c7 100644
--- a/ports/stm32/modmachine.h
+++ b/ports/stm32/modmachine.h
@@ -34,7 +34,7 @@ void machine_deinit(void);
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(machine_info_obj);
 MP_DECLARE_CONST_FUN_OBJ_0(machine_unique_id_obj);
 MP_DECLARE_CONST_FUN_OBJ_0(machine_reset_obj);
-MP_DECLARE_CONST_FUN_OBJ_0(machine_bootloader_obj);
+MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(machine_bootloader_obj);
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(machine_freq_obj);
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(machine_lightsleep_obj);
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(machine_deepsleep_obj);