stm32/vfs_rom_ioctl: Allow ROMFS configuration to be dynamic.

Options for a board to configure ROMFS are:

- Leave ROMFS disabled, do nothing.

- Enable by defining `MICROPY_HW_ROMFS_ENABLE_PARTx` to 1 and then in the
  linker script define `_micropy_hw_romfs_partX_start` and
  `_micropy_hw_romfs_partX_size`.

- Enable by defining `MICROPY_HW_ROMFS_ENABLE_PARTx` to 1 and also define
  `MICROPY_HW_ROMFS_PARTx_START` and `MICROPY_HW_ROMFS_PARTx_SIZE` which
  can be arbitrary expressions (not necessarily static)

Signed-off-by: Damien George <[email protected]>

Author: dpgeorge

ports/stm32/vfs_rom_ioctl.c

@@ -36,28 +36,32 @@
 
 #if MICROPY_VFS_ROM_IOCTL
 
-#if MICROPY_HW_ROMFS_ENABLE_PART0 && !defined(MICROPY_HW_ROMFS_PART0_START)
-#define MICROPY_HW_ROMFS_PART0_START (uintptr_t)(&_micropy_hw_romfs_part0_start)
-#define MICROPY_HW_ROMFS_PART0_SIZE (uintptr_t)(&_micropy_hw_romfs_part0_size)
+#if MICROPY_HW_ROMFS_ENABLE_PART0 && defined(MICROPY_HW_ROMFS_PART0_START)
+#define ROMFS0_DYNAMIC (1)
+static MP_DEFINE_MEMORYVIEW_OBJ(romfs0_obj, 'B', 0, (uintptr_t)-1, (void *)-1);
+#elif MICROPY_HW_ROMFS_ENABLE_PART0 && !defined(MICROPY_HW_ROMFS_PART0_START)
+#define ROMFS0_DYNAMIC (0)
 extern uint8_t _micropy_hw_romfs_part0_start;
 extern uint8_t _micropy_hw_romfs_part0_size;
+static const MP_DEFINE_MEMORYVIEW_OBJ(romfs0_obj, 'B', 0, (uintptr_t)&_micropy_hw_romfs_part0_size, (void *)&_micropy_hw_romfs_part0_start);
 #endif
 
-#if MICROPY_HW_ROMFS_ENABLE_PART1 && !defined(MICROPY_HW_ROMFS_PART1_START)
-#define MICROPY_HW_ROMFS_PART1_START (uintptr_t)(&_micropy_hw_romfs_part1_start)
-#define MICROPY_HW_ROMFS_PART1_SIZE (uintptr_t)(&_micropy_hw_romfs_part1_size)
+#if MICROPY_HW_ROMFS_ENABLE_PART1 && defined(MICROPY_HW_ROMFS_PART1_START)
+#define ROMFS1_DYNAMIC (1)
+static MP_DEFINE_MEMORYVIEW_OBJ(romfs1_obj, 'B', 0, (uintptr_t)-1, (void *)-1);
+#elif MICROPY_HW_ROMFS_ENABLE_PART1 && !defined(MICROPY_HW_ROMFS_PART1_START)
+#define ROMFS1_DYNAMIC (0)
 extern uint8_t _micropy_hw_romfs_part1_start;
 extern uint8_t _micropy_hw_romfs_part1_size;
+static const MP_DEFINE_MEMORYVIEW_OBJ(romfs1_obj, 'B', 0, (uintptr_t)&_micropy_hw_romfs_part1_size, (void *)&_micropy_hw_romfs_part1_start);
 #endif
 
-#define ROMFS_MEMORYVIEW(base, size) {{&mp_type_memoryview}, 'B', 0, (size), (void *)(base)}
-
-static const mp_obj_array_t romfs_obj_table[] = {
+static const mp_obj_array_t *romfs_obj_table[] = {
     #if MICROPY_HW_ROMFS_ENABLE_PART0
-    ROMFS_MEMORYVIEW(MICROPY_HW_ROMFS_PART0_START, MICROPY_HW_ROMFS_PART0_SIZE),
+    &romfs0_obj,
     #endif
     #if MICROPY_HW_ROMFS_ENABLE_PART1
-    ROMFS_MEMORYVIEW(MICROPY_HW_ROMFS_PART1_START, MICROPY_HW_ROMFS_PART1_SIZE),
+    &romfs1_obj,
     #endif
 };
 
@@ -76,7 +80,20 @@ mp_obj_t mp_vfs_rom_ioctl(size_t n_args, const mp_obj_t *args) {
         return MP_OBJ_NEW_SMALL_INT(-MP_EINVAL);
     }
 
-    const mp_obj_array_t *romfs_obj = &romfs_obj_table[romfs_id];
+    #if ROMFS0_DYNAMIC
+    if (romfs_id == 0) {
+        romfs0_obj.items = (void *)MICROPY_HW_ROMFS_PART0_START;
+        romfs0_obj.len = MICROPY_HW_ROMFS_PART0_SIZE;
+    }
+    #endif
+    #if ROMFS1_DYNAMIC
+    if (romfs_id == 1) {
+        romfs1_obj.items = (void *)MICROPY_HW_ROMFS_PART1_START;
+        romfs1_obj.len = MICROPY_HW_ROMFS_PART1_SIZE;
+    }
+    #endif
+
+    const mp_obj_array_t *romfs_obj = romfs_obj_table[romfs_id];
     uintptr_t romfs_base = (uintptr_t)romfs_obj->items;
     uintptr_t romfs_len = romfs_obj->len;