Initial work for STM32. Need to fix us delay and PulseIn still.

2 files changed, 8 insertions, 2 deletions

diff --git a/supervisor/shared/flash.c b/supervisor/shared/flash.c
index e0bf83490..298e7d83e 100644
--- a/supervisor/shared/flash.c
+++ b/supervisor/shared/flash.c
@@ -111,7 +111,7 @@ mp_uint_t flash_read_blocks(uint8_t *dest, uint32_t block_num, uint32_t num_bloc
     return supervisor_flash_read_blocks(dest, block_num - PART1_START_BLOCK, num_blocks);
 }
 
-volatile bool filesystem_dirty;
+volatile bool filesystem_dirty = false;
 
 mp_uint_t flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_t num_blocks) {
     if (block_num == 0) {
@@ -137,7 +137,9 @@ void supervisor_flash_flush(void) {
     supervisor_external_flash_flush();
     #endif
     // Turn off ticks now that our filesystem has been flushed.
-    supervisor_disable_tick();
+    if (filesystem_dirty) {
+        supervisor_disable_tick();
+    }
     filesystem_dirty = false;
 }
 
diff --git a/supervisor/shared/tick.c b/supervisor/shared/tick.c
index 80bd6f204..de56b64f5 100644
--- a/supervisor/shared/tick.c
+++ b/supervisor/shared/tick.c
@@ -118,18 +118,22 @@ void mp_hal_delay_ms(mp_uint_t delay) {
 
 volatile size_t tick_enable_count = 0;
 extern void supervisor_enable_tick(void) {
+    common_hal_mcu_disable_interrupts();
     if (tick_enable_count == 0) {
         port_enable_tick();
     }
     tick_enable_count++;
+    common_hal_mcu_enable_interrupts();
 }
 
 extern void supervisor_disable_tick(void) {
+    common_hal_mcu_disable_interrupts();
     if (tick_enable_count > 0) {
         tick_enable_count--;
     }
     if (tick_enable_count == 0) {
         port_disable_tick();
     }
+    common_hal_mcu_enable_interrupts();
 }