Fixups for adafruit#1042

Author: nickzoic

ports/nrf/common-hal/microcontroller/__init__.c

@@ -74,12 +74,9 @@ const nvm_bytearray_obj_t common_hal_mcu_nvm_obj = {
     .base = {
         .type = &nvm_bytearray_type,
     },
-    .len = CIRCUITPY_INTERNAL_NVM_SIZE,
-    .start_address = FLASH_SIZE - CIRCUITPY_INTERNAL_NVM_SIZE
 };
 #endif
 
-
 STATIC const mp_rom_map_elem_t mcu_pin_globals_table[] = {
   { MP_ROM_QSTR(MP_QSTR_P0_00), MP_ROM_PTR(&pin_P0_00) },
   { MP_ROM_QSTR(MP_QSTR_P0_01), MP_ROM_PTR(&pin_P0_01) },

ports/nrf/peripherals/nrf/nvm.h

@@ -25,4 +25,10 @@
  * THE SOFTWARE.
  */
 
+#define FLASH_PAGE_SIZE (4096)
+
+#ifndef CIRCUITPY_INTERNAL_NVM_SIZE
+#define CIRCUITPY_INTERNAL_NVM_SIZE (0)
+#endif
+
 void nrf_nvm_safe_flash_page_write(uint32_t page_addr, uint8_t *data);

ports/nrf/supervisor/internal_flash.c

@@ -67,13 +67,21 @@ uint32_t supervisor_flash_get_block_size(void) {
 }
 
 uint32_t supervisor_flash_get_block_count(void) {
-    return ((uint32_t) __fatfs_flash_length - CIRCUITPY_INTERNVAL_NVM_SIZE) / FILESYSTEM_BLOCK_SIZE ;
+    return ((uint32_t) __fatfs_flash_length - CIRCUITPY_INTERNAL_NVM_SIZE) / FILESYSTEM_BLOCK_SIZE ;
+}
+
+void supervisor_flash_flush(void) {
+    if (_flash_page_addr == NO_CACHE) return;
+
+    // Skip if data is the same
+    if (memcmp(_flash_cache, (void *)_flash_page_addr, FLASH_PAGE_SIZE) != 0) {
+        nrf_nvm_safe_flash_page_write(_flash_page_addr, _flash_cache);
+    }
 }
 
 mp_uint_t supervisor_flash_read_blocks(uint8_t *dest, uint32_t block, uint32_t num_blocks) {
     // Must write out anything in cache before trying to read.
-    nrf_nvm_safe_flash_page_write(_flash_page_addr, _flash_cache);
-    _flash_page_addr = NO_CACHE;
+    supervisor_flash_flush();
 
     uint32_t src = lba2addr(block);
     memcpy(dest, (uint8_t*) src, FILESYSTEM_BLOCK_SIZE*num_blocks);
@@ -107,3 +115,7 @@ mp_uint_t supervisor_flash_write_blocks(const uint8_t *src, uint32_t lba, uint32
 
     return 0; // success
 }
+
+void supervisor_flash_release_cache(void) {
+}
+

ports/nrf/supervisor/internal_flash.h

@@ -31,8 +31,6 @@
 
 #include "py/mpconfig.h"
 
-#define FLASH_PAGE_SIZE                 0x1000
-
 #define INTERNAL_FLASH_SYSTICK_MASK     (0x1ff) // 512ms
 #define INTERNAL_FLASH_IDLE_TICK(tick)  (((tick) & INTERNAL_FLASH_SYSTICK_MASK) == 2)