stm32/boards/STM32F769DISC: Add config to use external SPI as filesys.

This board now has the following 3 build configurations:
- mboot + external QSPI in XIP mode + internal filesystem
- mboot + external QSPI with filesystem (the default)
- no mboot + external QSPI with filesystem

ports/stm32/boards/STM32F769DISC/board_init.c

@@ -1,16 +1,19 @@
-#include "drivers/memory/spiflash.h"
+#include "storage.h"
 #include "qspi.h"
 
 // This configuration is needed for mboot to be able to write to the external QSPI flash
 
+STATIC mp_spiflash_cache_t spi_bdev_cache;
+
 const mp_spiflash_config_t spiflash_config = {
     .bus_kind = MP_SPIFLASH_BUS_QSPI,
     .bus.u_qspi.data = NULL,
     .bus.u_qspi.proto = &qspi_proto,
     .cache = NULL,
+    .cache = &spi_bdev_cache,
 };
 
-mp_spiflash_t spiflash_instance;
+spi_bdev_t spi_bdev;
 
 // This init function is needed to memory map the QSPI flash early in the boot process
 

ports/stm32/boards/STM32F769DISC/mpconfigboard.h

@@ -26,7 +26,7 @@ void board_early_init(void);
 
 #define MICROPY_HW_FLASH_LATENCY    FLASH_LATENCY_7 // 210-216 MHz needs 7 wait states
 
-// 512MBit external QSPI flash, to be memory mapped
+// 512MBit external QSPI flash, used for either the filesystem or XIP memory mapped
 #define MICROPY_HW_QSPIFLASH_SIZE_BITS_LOG2 (29)
 #define MICROPY_HW_QSPIFLASH_CS     (pin_B6)
 #define MICROPY_HW_QSPIFLASH_SCK    (pin_B2)
@@ -35,6 +35,21 @@ void board_early_init(void);
 #define MICROPY_HW_QSPIFLASH_IO2    (pin_E2)
 #define MICROPY_HW_QSPIFLASH_IO3    (pin_D13)
 
+// SPI flash, block device config (when used as the filesystem)
+extern const struct _mp_spiflash_config_t spiflash_config;
+extern struct _spi_bdev_t spi_bdev;
+#if !USE_QSPI_XIP
+#define MICROPY_HW_ENABLE_INTERNAL_FLASH_STORAGE (0)
+#define MICROPY_HW_BDEV_IOCTL(op, arg) ( \
+    (op) == BDEV_IOCTL_NUM_BLOCKS ? (64 * 1024 * 1024 / FLASH_BLOCK_SIZE) : \
+    (op) == BDEV_IOCTL_INIT ? spi_bdev_ioctl(&spi_bdev, (op), (uint32_t)&spiflash_config) : \
+    spi_bdev_ioctl(&spi_bdev, (op), (arg)) \
+)
+#define MICROPY_HW_BDEV_READBLOCKS(dest, bl, n) spi_bdev_readblocks(&spi_bdev, (dest), (bl), (n))
+#define MICROPY_HW_BDEV_WRITEBLOCKS(src, bl, n) spi_bdev_writeblocks(&spi_bdev, (src), (bl), (n))
+#define MICROPY_HW_BDEV_SPIFLASH_EXTENDED (&spi_bdev) // for extended block protocol
+#endif
+
 // UART config
 #define MICROPY_HW_UART1_TX         (pin_A9)
 #define MICROPY_HW_UART1_RX         (pin_A10)
@@ -199,11 +214,9 @@ void board_early_init(void);
 // Bootloader configuration
 
 // Give Mboot access to the external QSPI flash
-extern const struct _mp_spiflash_config_t spiflash_config;
-extern struct _mp_spiflash_t spiflash_instance;
 #define MBOOT_SPIFLASH_ADDR                     (0x90000000)
 #define MBOOT_SPIFLASH_BYTE_SIZE                (512 * 128 * 1024)
 #define MBOOT_SPIFLASH_LAYOUT                   "/0x90000000/512*128Kg"
 #define MBOOT_SPIFLASH_ERASE_BLOCKS_PER_PAGE    (128 / 4) // 128k page, 4k erase block
 #define MBOOT_SPIFLASH_CONFIG                   (&spiflash_config)
-#define MBOOT_SPIFLASH_SPIFLASH                 (&spiflash_instance)
+#define MBOOT_SPIFLASH_SPIFLASH                 (&spi_bdev.spiflash)

ports/stm32/boards/STM32F769DISC/mpconfigboard.mk

@@ -1,9 +1,11 @@
 # By default this board is configured to use mboot which must be deployed first
 USE_MBOOT ?= 1
 
-# By default this board puts some code into external QSPI flash set in XIP mode
+# By default the filesystem is in external QSPI flash.  But by setting the
+# following option this board puts some code into external flash set in XIP mode.
 # USE_MBOOT must be enabled; see f769_qspi.ld for code that goes in QSPI flash
-USE_QSPI ?= 1
+USE_QSPI_XIP ?= 0
+CFLAGS += -DUSE_QSPI_XIP=$(USE_QSPI_XIP)
 
 # MCU settings
 MCU_SERIES = f7
@@ -12,9 +14,11 @@ MICROPY_FLOAT_IMPL = double
 AF_FILE = boards/stm32f767_af.csv
 
 ifeq ($(USE_MBOOT),1)
-ifeq ($(USE_QSPI),1)
+ifeq ($(USE_QSPI_XIP),1)
 
-# When using Mboot and QSPI the text is split between internal and external flash
+# When using Mboot and QSPI-XIP the text is split between internal and external
+# QSPI flash, and the filesystem is in internal flash between the bootloader and
+# the main program text.
 LD_FILES = boards/STM32F769DISC/f769_qspi.ld
 TEXT0_ADDR = 0x08020000
 TEXT1_ADDR = 0x90000000
@@ -23,17 +27,19 @@ TEXT1_SECTIONS = .text_qspi
 
 else
 
-# When using Mboot but not QSPI all the text goes together after the filesystem
+# When using Mboot but not QSPI-XIP all the text goes together after the bootloader
+# (at same location as when QSPI-XIP is enabled so the same Mboot can be used for
+# either configuration) and the filesystem is in external flash.
 LD_FILES = boards/stm32f769.ld boards/common_blifs.ld
 TEXT0_ADDR = 0x08020000
 
 endif
 else
 
-# When not using Mboot the ISR text goes first, then the rest after the filesystem
-LD_FILES = boards/stm32f769.ld boards/common_ifs.ld
+# When not using Mboot (and so no ability to load text into QSPI) all the text goes
+# together at the start of internal flash, and the filesystem is in external flash.
+LD_FILES = boards/stm32f769.ld boards/common_basic.ld
 TEXT0_ADDR = 0x08000000
-TEXT1_ADDR = 0x08020000
 
 endif