dpgeorge
diff --git a/‎ports/rp2/modules/_boot.py
Lines changed: 8 additions & 1 deletion b/‎ports/rp2/modules/_boot.py
Lines changed: 8 additions & 1 deletion
diff --git a/‎ports/rp2/mpconfigport.h
Lines changed: 1 addition & 0 deletions b/‎ports/rp2/mpconfigport.h
Lines changed: 1 addition & 0 deletions
diff --git a/‎ports/rp2/rp2_flash.c
Lines changed: 39 additions & 0 deletions b/‎ports/rp2/rp2_flash.c
Lines changed: 39 additions & 0 deletions
@@ -1,6 +1,13 @@
 import vfs
+import sys
 import machine, rp2
 
+# Try to mount the ROMFS.
+try:
+    vfs.mount(vfs.VfsRom(vfs.rom_ioctl(2)), "/rom")
+    sys.path.insert(0, "/rom")
+except:
+    pass
 
 # Try to mount the filesystem, and format the flash if it doesn't exist.
 # Note: the flash requires the programming size to be aligned to 256 bytes.
@@ -12,4 +19,4 @@
     fs = vfs.VfsLfs2(bdev, progsize=256)
 vfs.mount(fs, "/")
 
-del vfs, bdev, fs
+del vfs, sys, bdev, fs
@@ -170,6 +170,7 @@
 #define MICROPY_VFS                             (1)
 #define MICROPY_VFS_LFS2                        (1)
 #define MICROPY_VFS_FAT                         (1)
+#define MICROPY_VFS_ROM                         (1)
 #define MICROPY_SSL_MBEDTLS                     (1)
 #define MICROPY_PY_LWIP_PPP                     (MICROPY_PY_NETWORK_PPP_LWIP)
 #define MICROPY_PY_LWIP_SOCK_RAW                (MICROPY_PY_LWIP)
 
@@ -28,6 +28,7 @@
 
 #include "py/mphal.h"
 #include "py/runtime.h"
+#include "py/mperrno.h"
 #include "extmod/vfs.h"
 #include "modrp2.h"
 #include "hardware/flash.h"
@@ -44,6 +45,9 @@ static_assert(MICROPY_HW_FLASH_STORAGE_BYTES % 4096 == 0, "Flash storage size mu
 #define MICROPY_HW_FLASH_STORAGE_BASE (PICO_FLASH_SIZE_BYTES - MICROPY_HW_FLASH_STORAGE_BYTES)
 #endif
 
+#define MICROPY_HW_ROMFS_BASE (512 * 1024) // leave 512k for firmware...
+#define MICROPY_HW_ROMFS_BYTES (MICROPY_HW_FLASH_STORAGE_BASE - MICROPY_HW_ROMFS_BASE)
+
 static_assert(MICROPY_HW_FLASH_STORAGE_BYTES <= PICO_FLASH_SIZE_BYTES, "MICROPY_HW_FLASH_STORAGE_BYTES too big");
 static_assert(MICROPY_HW_FLASH_STORAGE_BASE + MICROPY_HW_FLASH_STORAGE_BYTES <= PICO_FLASH_SIZE_BYTES, "MICROPY_HW_FLASH_STORAGE_BYTES too big");
 
@@ -59,6 +63,14 @@ static rp2_flash_obj_t rp2_flash_obj = {
     .flash_size = MICROPY_HW_FLASH_STORAGE_BYTES,
 };
 
+#if MICROPY_HW_ROMFS_BYTES > 0
+static rp2_flash_obj_t rp2_flash_romfs_obj = {
+    .base = { &rp2_flash_type },
+    .flash_base = MICROPY_HW_ROMFS_BASE,
+    .flash_size = MICROPY_HW_ROMFS_BYTES,
+};
+#endif
+
 // Tag the flash drive in the binary as readable/writable (but not reformatable)
 bi_decl(bi_block_device(
     BINARY_INFO_TAG_MICROPYTHON,
@@ -138,6 +150,19 @@ static mp_obj_t rp2_flash_make_new(const mp_obj_type_t *type, size_t n_args, siz
     return MP_OBJ_FROM_PTR(self);
 }
 
+static mp_int_t rp2_flash_get_buffer(mp_obj_t self_in, mp_buffer_info_t *bufinfo, mp_uint_t flags) {
+    rp2_flash_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    if (flags == MP_BUFFER_READ) {
+        bufinfo->buf = (void *)(XIP_BASE + self->flash_base);
+        bufinfo->len = self->flash_size;
+        bufinfo->typecode = 'B';
+        return 0;
+    } else {
+        // Write unsupported.
+        return 1;
+    }
+}
+
 static mp_obj_t rp2_flash_readblocks(size_t n_args, const mp_obj_t *args) {
     rp2_flash_obj_t *self = MP_OBJ_TO_PTR(args[0]);
     uint32_t offset = mp_obj_get_int(args[1]) * BLOCK_SIZE_BYTES;
@@ -218,5 +243,19 @@ MP_DEFINE_CONST_OBJ_TYPE(
     MP_QSTR_Flash,
     MP_TYPE_FLAG_NONE,
     make_new, rp2_flash_make_new,
+    buffer, rp2_flash_get_buffer,
     locals_dict, &rp2_flash_locals_dict
     );
+
+mp_obj_t mp_vfs_rom_ioctl(size_t n_args, const mp_obj_t *args) {
+    switch (mp_obj_get_int(args[0])) {
+        #if MICROPY_HW_ROMFS_BYTES > 0
+        case MP_VFS_ROM_IOCTL_GET_NUMBER_OF_SEGMENTS:
+            return MP_OBJ_NEW_SMALL_INT(1);
+        case MP_VFS_ROM_IOCTL_GET_SEGMENT:
+            return MP_OBJ_FROM_PTR(&rp2_flash_romfs_obj);
+        #endif
+        default:
+            return MP_OBJ_NEW_SMALL_INT(-MP_EINVAL);
+    }
+}