Merge branch 'master' into nfc_copy

18 files changed, 264 insertions, 28 deletions

diff --git a/supervisor/linker.h b/supervisor/linker.h
new file mode 100755
index 000000000..d68be2437
--- /dev/null
+++ b/supervisor/linker.h
@@ -0,0 +1,42 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Scott Shawcroft for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+// These macros are used to place code and data into different linking sections.
+
+#ifndef MICROPY_INCLUDED_SUPERVISOR_LINKER_H
+#define MICROPY_INCLUDED_SUPERVISOR_LINKER_H
+
+#if defined(IMXRT10XX) || defined(FOMU)
+#define PLACE_IN_DTCM_DATA(name) name __attribute__((section(".dtcm_data." #name )))
+#define PLACE_IN_DTCM_BSS(name) name __attribute__((section(".dtcm_bss." #name )))
+#define PLACE_IN_ITCM(name) __attribute__((section(".itcm." #name ))) name
+#else
+#define PLACE_IN_DTCM_DATA(name) name
+#define PLACE_IN_DTCM_BSS(name) name
+#define PLACE_IN_ITCM(name) name
+#endif
+
+#endif  // MICROPY_INCLUDED_SUPERVISOR_LINKER_H
diff --git a/supervisor/port.h b/supervisor/port.h
index c8a011978..b289583dd 100644
--- a/supervisor/port.h
+++ b/supervisor/port.h
@@ -60,6 +60,12 @@ uint32_t *port_stack_get_limit(void);
 // Get stack top address
 uint32_t *port_stack_get_top(void);
 
+// Get heap bottom address
+uint32_t *port_heap_get_bottom(void);
+
+// Get heap top address
+uint32_t *port_heap_get_top(void);
+
 // Save and retrieve a word from memory that is preserved over reset. Used for safe mode.
 void port_set_saved_word(uint32_t);
 uint32_t port_get_saved_word(void);
diff --git a/supervisor/shared/bluetooth.c b/supervisor/shared/bluetooth.c
index 18caa2eb4..b463160cf 100644
--- a/supervisor/shared/bluetooth.c
+++ b/supervisor/shared/bluetooth.c
@@ -64,6 +64,9 @@ mp_obj_list_t characteristic_list;
 mp_obj_t characteristic_list_items[4];
 
 void supervisor_bluetooth_start_advertising(void) {
+    #if !CIRCUITPY_BLE_FILE_SERVICE
+    return;
+    #endif
     bool is_connected = common_hal_bleio_adapter_get_connected(&common_hal_bleio_adapter_obj);
     if (is_connected) {
         return;
@@ -79,6 +82,10 @@ void supervisor_bluetooth_start_advertising(void) {
 }
 
 void supervisor_start_bluetooth(void) {
+    #if !CIRCUITPY_BLE_FILE_SERVICE
+    return;
+    #endif
+
     common_hal_bleio_adapter_set_enabled(&common_hal_bleio_adapter_obj, true);
 
     supervisor_ble_service_uuid.base.type = &bleio_uuid_type;
@@ -203,6 +210,9 @@ uint32_t current_command[1024 / sizeof(uint32_t)];
 volatile size_t current_offset;
 
 void supervisor_bluetooth_background(void) {
+    #if !CIRCUITPY_BLE_FILE_SERVICE
+    return;
+    #endif
     if (!run_ble_background) {
         return;
     }
@@ -296,6 +306,9 @@ void supervisor_bluetooth_background(void) {
 
 // This happens in an interrupt so we need to be quick.
 bool supervisor_bluetooth_hook(ble_evt_t *ble_evt) {
+    #if !CIRCUITPY_BLE_FILE_SERVICE
+    return false;
+    #endif
     // Catch writes to filename or contents. Length is read-only.
 
     bool done = false;
diff --git a/supervisor/shared/board.c b/supervisor/shared/board.c
new file mode 100644
index 000000000..e3eb8fd0d
--- /dev/null
+++ b/supervisor/shared/board.c
@@ -0,0 +1,49 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Dan Halbert for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "supervisor/shared/board.h"
+
+#include "shared-bindings/digitalio/DigitalInOut.h"
+#include "shared-bindings/neopixel_write/__init__.h"
+
+#ifdef USER_NEOPIXELS_PIN
+
+// The maximum number of user neopixels right now is 10, on Circuit Playgrounds.
+// PyBadge and PyGamer have max 5
+#define USER_NEOPIXELS_MAX_COUNT 10
+
+void board_reset_user_neopixels(void) {
+    // Turn off on-board NeoPixel string
+    uint8_t empty[USER_NEOPIXELS_MAX_COUNT * 3] = { 0 };
+    digitalio_digitalinout_obj_t neopixel_pin;
+    common_hal_digitalio_digitalinout_construct(&neopixel_pin, USER_NEOPIXELS_PIN);
+    common_hal_digitalio_digitalinout_switch_to_output(&neopixel_pin, false,
+        DRIVE_MODE_PUSH_PULL);
+    common_hal_neopixel_write(&neopixel_pin, empty, USER_NEOPIXELS_MAX_COUNT * 3);
+    common_hal_digitalio_digitalinout_deinit(&neopixel_pin);
+}
+
+#endif
diff --git a/supervisor/shared/board.h b/supervisor/shared/board.h
new file mode 100644
index 000000000..0e4d73455
--- /dev/null
+++ b/supervisor/shared/board.h
@@ -0,0 +1,38 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Dan Halbert for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_SUPERVISOR_BOARD_H
+#define MICROPY_INCLUDED_SUPERVISOR_BOARD_H
+
+#include "py/mpconfig.h"
+
+#ifdef USER_NEOPIXELS_PIN
+
+void board_reset_user_neopixels(void);
+
+#endif
+
+#endif  // MICROPY_INCLUDED_SUPERVISOR_BOARD_H
diff --git a/supervisor/shared/external_flash/devices.h b/supervisor/shared/external_flash/devices.h
index 08d0a78fd..fd9224f56 100644
--- a/supervisor/shared/external_flash/devices.h
+++ b/supervisor/shared/external_flash/devices.h
@@ -105,6 +105,25 @@ typedef struct {
     .single_status_byte = false, \
 }
 
+// Settings for the Adesto Tech AT25SF041 1MiB SPI flash. It's on the SparkFun
+// SAMD51 Thing Plus board
+// Datasheet: https://www.adestotech.com/wp-content/uploads/DS-AT25SF041_044.pdf
+#define AT25SF041A {\
+    .total_size = (1 << 19), /* 512 KiB */ \
+    .start_up_time_us = 10000, \
+    .manufacturer_id = 0x1f, \
+    .memory_type = 0x84, \
+    .capacity = 0x01, \
+    .max_clock_speed_mhz = 85, \
+    .quad_enable_bit_mask = 0x00, \
+    .has_sector_protection = false, \
+    .supports_fast_read = true, \
+    .supports_qspi = false, \
+    .supports_qspi_writes = false, \
+    .write_status_register_split = false, \
+    .single_status_byte = false, \
+}
+
 // Settings for the Gigadevice GD25Q16C 2MiB SPI flash.
 // Datasheet: http://www.gigadevice.com/datasheet/gd25q16c/
 #define GD25Q16C {\
@@ -371,6 +390,23 @@ typedef struct {
     .single_status_byte = false, \
 }
 
+// Settings for the Winbond W25Q80DV 1MiB SPI flash.. Note that W25Q80DL has a different memory type (0x60)
+// Datasheet: https://www.winbond.com/resource-files/w25q80dv%20dl_revh_10022015.pdf
+#define W25Q80DV {\
+    .total_size = (1 << 20), /* 1 MiB */ \
+    .start_up_time_us = 5000, \
+    .manufacturer_id = 0xef, \
+    .memory_type = 0x40, \
+    .capacity = 0x14, \
+    .max_clock_speed_mhz = 104, \
+    .quad_enable_bit_mask = 0x02, \
+    .has_sector_protection = false, \
+    .supports_fast_read = true, \
+    .supports_qspi = true, \
+    .supports_qspi_writes = false, \
+    .write_status_register_split = false, \
+    .single_status_byte = false, \
+}
 
 // Settings for the Winbond W25Q128JV-SQ 16MiB SPI flash. Note that JV-IM has a different .memory_type (0x70)
 // Datasheet: https://www.winbond.com/resource-files/w25q128jv%20revf%2003272018%20plus.pdf
@@ -445,6 +481,24 @@ typedef struct {
     .single_status_byte = true, \
 }
 
+// Settings for the Macronix MX25L51245G 64MiB SPI flash.
+// Datasheet: https://www.macronix.com/Lists/Datasheet/Attachments/7437/MX25L51245G,%203V,%20512Mb,%20v1.6.pdf
+#define MX25L51245G  {\
+    .total_size = (1 << 26), /* 64 MiB */ \
+    .start_up_time_us = 5000, \
+    .manufacturer_id = 0xc2, \
+    .memory_type = 0x20, \
+    .capacity = 0x1a, \
+    .max_clock_speed_mhz = 133, \
+    .quad_enable_bit_mask = 0x40, \
+    .has_sector_protection = false, \
+    .supports_fast_read = true, \
+    .supports_qspi = true, \
+    .supports_qspi_writes = true, \
+    .write_status_register_split = false, \
+    .single_status_byte = true, \
+}
+
 // Settings for the Winbond W25Q128JV-PM 16MiB SPI flash. Note that JV-IM has a different .memory_type (0x70)
 // Datasheet: https://www.winbond.com/resource-files/w25q128jv%20revf%2003272018%20plus.pdf
 #define W25Q128JV_PM {\
diff --git a/supervisor/shared/external_flash/spi_flash.c b/supervisor/shared/external_flash/spi_flash.c
index 12888f2d3..67e64c970 100644
--- a/supervisor/shared/external_flash/spi_flash.c
+++ b/supervisor/shared/external_flash/spi_flash.c
@@ -36,33 +36,33 @@
 #include "py/mpconfig.h"
 
 digitalio_digitalinout_obj_t cs_pin;
-busio_spi_obj_t spi;
+busio_spi_obj_t supervisor_flash_spi_bus;
 
 const external_flash_device* flash_device;
 uint32_t spi_flash_baudrate;
 
 // Enable the flash over SPI.
 static void flash_enable(void) {
-    while (!common_hal_busio_spi_try_lock(&spi)) {}
+    while (!common_hal_busio_spi_try_lock(&supervisor_flash_spi_bus)) {}
     common_hal_digitalio_digitalinout_set_value(&cs_pin, false);
 }
 
 // Disable the flash over SPI.
 static void flash_disable(void) {
     common_hal_digitalio_digitalinout_set_value(&cs_pin, true);
-    common_hal_busio_spi_unlock(&spi);
+    common_hal_busio_spi_unlock(&supervisor_flash_spi_bus);
 }
 
 static bool transfer(uint8_t* command, uint32_t command_length, uint8_t* data_in, uint8_t* data_out, uint32_t data_length) {
     flash_enable();
-    bool status = common_hal_busio_spi_write(&spi, command, command_length);
+    bool status = common_hal_busio_spi_write(&supervisor_flash_spi_bus, command, command_length);
     if (status) {
         if (data_in != NULL && data_out != NULL) {
-            status = common_hal_busio_spi_transfer(&spi, data_out, data_in, data_length);
+            status = common_hal_busio_spi_transfer(&supervisor_flash_spi_bus, data_out, data_in, data_length);
         } else if (data_out != NULL) {
-            status = common_hal_busio_spi_read(&spi, data_out, data_length, 0xff);
+            status = common_hal_busio_spi_read(&supervisor_flash_spi_bus, data_out, data_length, 0xff);
         } else if (data_in != NULL) {
-            status = common_hal_busio_spi_write(&spi, data_in, data_length);
+            status = common_hal_busio_spi_write(&supervisor_flash_spi_bus, data_in, data_length);
         }
     }
     flash_disable();
@@ -103,10 +103,10 @@ bool spi_flash_write_data(uint32_t address, uint8_t* data, uint32_t data_length)
     // Write the SPI flash write address into the bytes following the command byte.
     address_to_bytes(address, request + 1);
     flash_enable();
-    common_hal_busio_spi_configure(&spi, spi_flash_baudrate, 0, 0, 8);
-    bool status = common_hal_busio_spi_write(&spi, request, 4);
+    common_hal_busio_spi_configure(&supervisor_flash_spi_bus, spi_flash_baudrate, 0, 0, 8);
+    bool status = common_hal_busio_spi_write(&supervisor_flash_spi_bus, request, 4);
     if (status) {
-        status = common_hal_busio_spi_write(&spi, data, data_length);
+        status = common_hal_busio_spi_write(&supervisor_flash_spi_bus, data, data_length);
     }
     flash_disable();
     return status;
@@ -122,10 +122,10 @@ bool spi_flash_read_data(uint32_t address, uint8_t* data, uint32_t data_length)
     // Write the SPI flash write address into the bytes following the command byte.
     address_to_bytes(address, request + 1);
     flash_enable();
-    common_hal_busio_spi_configure(&spi, spi_flash_baudrate, 0, 0, 8);
-    bool status = common_hal_busio_spi_write(&spi, request, command_length);
+    common_hal_busio_spi_configure(&supervisor_flash_spi_bus, spi_flash_baudrate, 0, 0, 8);
+    bool status = common_hal_busio_spi_write(&supervisor_flash_spi_bus, request, command_length);
     if (status) {
-        status = common_hal_busio_spi_read(&spi, data, data_length, 0xff);
+        status = common_hal_busio_spi_read(&supervisor_flash_spi_bus, data, data_length, 0xff);
     }
     flash_disable();
     return status;
@@ -140,9 +140,9 @@ void spi_flash_init(void) {
     common_hal_digitalio_digitalinout_switch_to_output(&cs_pin, true, DRIVE_MODE_PUSH_PULL);
     common_hal_digitalio_digitalinout_never_reset(&cs_pin);
 
-    spi.base.type = &busio_spi_type;
-    common_hal_busio_spi_construct(&spi, SPI_FLASH_SCK_PIN, SPI_FLASH_MOSI_PIN, SPI_FLASH_MISO_PIN);
-    common_hal_busio_spi_never_reset(&spi);
+    supervisor_flash_spi_bus.base.type = &busio_spi_type;
+    common_hal_busio_spi_construct(&supervisor_flash_spi_bus, SPI_FLASH_SCK_PIN, SPI_FLASH_MOSI_PIN, SPI_FLASH_MISO_PIN);
+    common_hal_busio_spi_never_reset(&supervisor_flash_spi_bus);
 }
 
 void spi_flash_init_device(const external_flash_device* device) {
diff --git a/supervisor/shared/filesystem.c b/supervisor/shared/filesystem.c
index 92727f6fb..f6b94e38b 100644
--- a/supervisor/shared/filesystem.c
+++ b/supervisor/shared/filesystem.c
@@ -75,7 +75,7 @@ static void make_sample_code_file(FATFS *fatfs) {
     FIL fs;
     UINT char_written = 0;
     const byte buffer[] = "print('Hello World!')\n";
-    //Create or modify existing code.py file 
+    //Create or modify existing code.py file
     f_open(fatfs, &fs, "/code.py", FA_WRITE | FA_CREATE_ALWAYS);
     f_write(&fs, buffer, sizeof(buffer) - 1, &char_written);
     f_close(&fs);
@@ -104,7 +104,11 @@ void filesystem_init(bool create_allowed, bool force_create) {
         }
 
         // set label
+#ifdef CIRCUITPY_DRIVE_LABEL
+        f_setlabel(&vfs_fat->fatfs, CIRCUITPY_DRIVE_LABEL);
+#else
         f_setlabel(&vfs_fat->fatfs, "CIRCUITPY");
+#endif
 
         // inhibit file indexing on MacOS
         f_mkdir(&vfs_fat->fatfs, "/.fseventsd");
diff --git a/supervisor/shared/memory.c b/supervisor/shared/memory.c
index 38040d11d..14c3b4979 100755
--- a/supervisor/shared/memory.c
+++ b/supervisor/shared/memory.c
@@ -39,11 +39,14 @@ uint32_t* low_address;
 uint32_t* high_address;
 
 void memory_init(void) {
-    low_address = port_stack_get_limit();
-    high_address = port_stack_get_top();
+    low_address = port_heap_get_bottom();
+    high_address = port_heap_get_top();
 }
 
 void free_memory(supervisor_allocation* allocation) {
+    if (allocation == NULL) {
+        return;
+    }
     int32_t index = 0;
     bool found = false;
     for (index = 0; index < CIRCUITPY_SUPERVISOR_ALLOC_COUNT; index++) {
diff --git a/supervisor/shared/rgb_led_status.c b/supervisor/shared/rgb_led_status.c
index f751a7ffd..f3c210647 100644
--- a/supervisor/shared/rgb_led_status.c
+++ b/supervisor/shared/rgb_led_status.c
@@ -115,7 +115,7 @@ void rgb_led_status_init() {
         shared_module_bitbangio_spi_construct(&status_apa102,
                                               MICROPY_HW_APA102_SCK,
                                               MICROPY_HW_APA102_MOSI,
-                                              mp_const_none);
+                                              NULL);
         #else
         if (!common_hal_busio_spi_deinited(&status_apa102)) {
             // This may call us recursively if common_hal_reset_pin() is called,
@@ -125,7 +125,7 @@ void rgb_led_status_init() {
         common_hal_busio_spi_construct(&status_apa102,
                                       MICROPY_HW_APA102_SCK,
                                       MICROPY_HW_APA102_MOSI,
-                                      mp_const_none);
+                                      NULL);
         common_hal_busio_spi_never_reset(&status_apa102);
         #endif
         // Pretend we aren't using the pins. bitbangio.SPI will
diff --git a/supervisor/shared/safe_mode.c b/supervisor/shared/safe_mode.c
index aba31e9c9..c957aee53 100644
--- a/supervisor/shared/safe_mode.c
+++ b/supervisor/shared/safe_mode.c
@@ -157,6 +157,9 @@ void print_safe_mode_message(safe_mode_t reason) {
             case FLASH_WRITE_FAIL:
                 serial_write_compressed(translate("Failed to write internal flash."));
                 break;
+            case MEM_MANAGE:
+                serial_write_compressed(translate("Invalid memory access."));
+                break;
             default:
                 serial_write_compressed(translate("Unknown reason."));
                 break;
diff --git a/supervisor/shared/safe_mode.h b/supervisor/shared/safe_mode.h
index e05fca0e4..5b09c4b54 100644
--- a/supervisor/shared/safe_mode.h
+++ b/supervisor/shared/safe_mode.h
@@ -40,6 +40,7 @@ typedef enum {
   PROGRAMMATIC_SAFE_MODE,
   NORDIC_SOFT_DEVICE_ASSERT,
   FLASH_WRITE_FAIL,
+  MEM_MANAGE,
 } safe_mode_t;
 
 safe_mode_t wait_for_safe_mode_reset(void);
diff --git a/supervisor/shared/stack.c b/supervisor/shared/stack.c
index dcecf2067..2b7b1c03a 100755
--- a/supervisor/shared/stack.c
+++ b/supervisor/shared/stack.c
@@ -46,6 +46,10 @@ void allocate_stack(void) {
 
     mp_uint_t c_size = (uint32_t) port_stack_get_top() - sp;
 
+    if (port_stack_get_top() != port_heap_get_top()) {
+        return;
+    }
+
     stack_alloc = allocate_memory(c_size + next_stack_size + EXCEPTION_STACK_SIZE, true);
     if (stack_alloc == NULL) {
         stack_alloc = allocate_memory(c_size + CIRCUITPY_DEFAULT_STACK_SIZE + EXCEPTION_STACK_SIZE, true);
@@ -71,6 +75,9 @@ void stack_init(void) {
 }
 
 void stack_resize(void) {
+    if (stack_alloc == NULL) {
+        return;
+    }
     if (next_stack_size == current_stack_size) {
         *stack_alloc->ptr = STACK_CANARY_VALUE;
         return;
diff --git a/supervisor/shared/tick.c b/supervisor/shared/tick.c
index 69256081c..5668f8fa1 100644
--- a/supervisor/shared/tick.c
+++ b/supervisor/shared/tick.c
@@ -25,11 +25,13 @@
  */
 
 #include "supervisor/shared/tick.h"
+
+#include "supervisor/linker.h"
 #include "supervisor/filesystem.h"
 #include "supervisor/shared/autoreload.h"
 
-static volatile uint64_t ticks_ms;
-static volatile uint32_t background_ticks_ms32;
+static volatile uint64_t PLACE_IN_DTCM_BSS(ticks_ms);
+static volatile uint32_t PLACE_IN_DTCM_BSS(background_ticks_ms32);
 
 #if CIRCUITPY_GAMEPAD
 #include "shared-module/gamepad/__init__.h"
@@ -77,7 +79,7 @@ uint32_t supervisor_ticks_ms32() {
 
 extern void run_background_tasks(void);
 
-void supervisor_run_background_tasks_if_tick() {
+void PLACE_IN_ITCM(supervisor_run_background_tasks_if_tick)() {
     uint32_t now32 = ticks_ms;
 
     if (now32 == background_ticks_ms32) {
diff --git a/supervisor/shared/usb/usb_msc_flash.c b/supervisor/shared/usb/usb_msc_flash.c
index 0376cfc1d..7532b6aea 100644
--- a/supervisor/shared/usb/usb_msc_flash.c
+++ b/supervisor/shared/usb/usb_msc_flash.c
@@ -39,7 +39,7 @@
 
 #define MSC_FLASH_BLOCK_SIZE    512
 
-static bool ejected[1];
+static bool ejected[1] = {true};
 
 void usb_msc_mount(void) {
     // Reset the ejection tracking every time we're plugged into USB. This allows for us to battery
@@ -53,6 +53,14 @@ void usb_msc_umount(void) {
 
 }
 
+bool usb_msc_ejected(void) {
+    bool all_ejected = true;
+    for (uint8_t i = 0; i < sizeof(ejected); i++) {
+        all_ejected &= ejected[i];
+    }
+    return all_ejected;
+}
+
 // The root FS is always at the end of the list.
 static fs_user_mount_t* get_vfs(int lun) {
     // TODO(tannewt): Return the mount which matches the lun where 0 is the end
@@ -200,6 +208,8 @@ bool tud_msc_test_unit_ready_cb(uint8_t lun) {
         return false;
     }
     if (ejected[lun]) {
+        // Set 0x3a for media not present.
+        tud_msc_set_sense(lun, SCSI_SENSE_NOT_READY, 0x3A, 0x00);
         return false;
     }
 
@@ -235,10 +245,8 @@ bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, boo
             if (disk_ioctl(current_mount, CTRL_SYNC, NULL) != RES_OK) {
                 return false;
             }
-        } else {
-            // Start the unit, but only if not ejected.
-            return !ejected[lun];
         }
+        // Always start the unit, even if ejected. Whether media is present is a separate check.
     }
 
     return true;
diff --git a/supervisor/spi_flash_api.h b/supervisor/spi_flash_api.h
index 28cccb1b1..f59346e25 100644
--- a/supervisor/spi_flash_api.h
+++ b/supervisor/spi_flash_api.h
@@ -31,6 +31,10 @@
 
 #include "supervisor/shared/external_flash/devices.h"
 
+#include "shared-bindings/busio/SPI.h"
+
+extern busio_spi_obj_t supervisor_flash_spi_bus; //Used to share SPI bus on some boards
+
 // This API is implemented for both normal SPI peripherals and QSPI peripherals.
 
 bool spi_flash_command(uint8_t command);
diff --git a/supervisor/supervisor.mk b/supervisor/supervisor.mk
index 96a14c25b..52d60b52b 100644
--- a/supervisor/supervisor.mk
+++ b/supervisor/supervisor.mk
@@ -2,6 +2,7 @@ SRC_SUPERVISOR = \
 	main.c \
 	supervisor/port.c \
 	supervisor/shared/autoreload.c \
+	supervisor/shared/board.c \
 	supervisor/shared/display.c \
 	supervisor/shared/filesystem.c \
 	supervisor/shared/flash.c \
diff --git a/supervisor/usb.h b/supervisor/usb.h
index 0cc361619..29280c725 100644
--- a/supervisor/usb.h
+++ b/supervisor/usb.h
@@ -44,5 +44,6 @@ void usb_init(void);
 // Propagate plug/unplug events to the MSC logic.
 void usb_msc_mount(void);
 void usb_msc_umount(void);
+bool usb_msc_ejected(void);
 
 #endif // MICROPY_INCLUDED_SUPERVISOR_USB_H