stm32/mboot: Add support for STM32N6xx MCUs.

Works in the usual USB DFU mode, and can program external SPI flash.  It
will enable XSPI memory-mapped mode before jumping to the application
firmware in the external SPI flash.

Signed-off-by: Damien George <damien@micropython.org>

ports/stm32/mboot/Makefile

@@ -34,7 +34,13 @@ include ../../../py/mkenv.mk
 include $(BOARD_DIR)/mpconfigboard.mk
 
 # A board can set MBOOT_TEXT0_ADDR to a custom location where mboot should reside.
+ifeq ($(MCU_SERIES),n6)
+MBOOT_TEXT0_ADDR ?= 0x34180400
+MBOOT_LD_FILES ?= stm32_memory_n6.ld stm32_sections.ld
+else
 MBOOT_TEXT0_ADDR ?= 0x08000000
+MBOOT_LD_FILES ?= stm32_memory.ld stm32_sections.ld
+endif
 
 # The string in MBOOT_VERSION (default defined in version.c if not defined by a
 # board) will be stored in the final MBOOT_VERSION_ALLOCATED_BYTES bytes of mboot flash.
@@ -89,7 +95,6 @@ CFLAGS += -DMBOOT_VERSION=\"$(MBOOT_VERSION)\"
 endif
 CFLAGS += -DMBOOT_VERSION_ALLOCATED_BYTES=$(MBOOT_VERSION_ALLOCATED_BYTES) -DMBOOT_VERSION_INCLUDE_OPTIONS=$(MBOOT_VERSION_INCLUDE_OPTIONS)
 
-MBOOT_LD_FILES ?= stm32_memory.ld stm32_sections.ld
 LDFLAGS += -nostdlib -L . $(addprefix -T,$(MBOOT_LD_FILES)) -Map=$(@:.elf=.map) --cref
 LDFLAGS += --defsym mboot_version_len=$(MBOOT_VERSION_ALLOCATED_BYTES)
 LIBS += $(shell $(CC) $(CFLAGS) -print-libgcc-file-name)
@@ -137,12 +142,11 @@ SRC_C += \
 	drivers/bus/softqspi.c \
 	drivers/memory/spiflash.c \
 	ports/stm32/flash.c \
-	ports/stm32/flashbdev.c \
 	ports/stm32/i2cslave.c \
 	ports/stm32/powerctrlboot.c \
 	ports/stm32/qspi.c \
-	ports/stm32/spibdev.c \
 	ports/stm32/usbd_conf.c \
+	ports/stm32/xspi.c \
 	$(wildcard $(BOARD_DIR)/*.c)
 
 SRC_O += \
@@ -169,16 +173,22 @@ SRC_HAL += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
 	hal.c \
 	hal_cortex.c \
 	hal_dma.c \
-	hal_flash.c \
-	hal_flash_ex.c \
 	hal_pcd.c \
 	hal_pcd_ex.c \
 	hal_pwr_ex.c \
 	hal_rcc.c \
 	hal_rcc_ex.c \
+	ll_rcc.c \
 	ll_usb.c \
 	)
 
+ifneq ($(MCU_SERIES),n6)
+SRC_HAL += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
+	hal_flash.c \
+	hal_flash_ex.c \
+	)
+endif
+
 ifeq ($(MCU_SERIES),$(filter $(MCU_SERIES),f4 f7 h7))
 SRC_HAL += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
 	hal_mmc.c \
@@ -187,6 +197,12 @@ SRC_HAL += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
 	)
 endif
 
+ifeq ($(MCU_SERIES),n6)
+SRC_HAL += $(addprefix $(STM32LIB_HAL_BASE)/Src/stm32$(MCU_SERIES)xx_,\
+	hal_bsec.c \
+	)
+endif
+
 SRC_USBDEV += $(addprefix ports/stm32/$(USBDEV_DIR)/,\
 	core/src/usbd_core.c \
 	core/src/usbd_ctlreq.c \
@@ -206,7 +222,7 @@ $(TOP)/lib/stm32lib/README.md:
 	$(ECHO) "stm32lib submodule not found, fetching it now..."
 	(cd $(TOP) && git submodule update --init lib/stm32lib)
 
-.PHONY: deploy deploy-stlink
+.PHONY: deploy deploy-stlink deploy-trusted
 
 deploy: $(BUILD)/firmware.dfu
 	$(ECHO) "Writing $< to the board"
@@ -216,9 +232,15 @@ deploy-stlink: $(BUILD)/firmware.dfu
 	$(ECHO) "Writing $< to the board via ST-LINK"
 	$(Q)$(STFLASH) write $(BUILD)/firmware.bin $(MBOOT_TEXT0_ADDR)
 
-$(BUILD)/firmware.dfu: $(BUILD)/firmware.elf
+deploy-trusted: $(BUILD)/firmware-trusted.bin
+	$(STM32_CUBE_PROGRAMMER)/bin/STM32_Programmer.sh -c port=SWD mode=HOTPLUG ap=1 -el $(DKEL) -w $^ 0x70000000 -hardRst
+
+$(BUILD)/firmware.bin: $(BUILD)/firmware.elf
 	$(ECHO) "Create $@"
 	$(Q)$(OBJCOPY) -O binary -j .isr_vector -j .text -j .data -j .mboot_version_text $^ $(BUILD)/firmware.bin
+
+$(BUILD)/firmware.dfu: $(BUILD)/firmware.bin
+	$(ECHO) "Create $@"
 	$(Q)$(PYTHON) $(DFU) -b $(MBOOT_TEXT0_ADDR):$(BUILD)/firmware.bin $@
 
 $(BUILD)/firmware.hex: $(BUILD)/firmware.elf
@@ -230,6 +252,10 @@ $(BUILD)/firmware.elf: $(OBJ)
 	$(Q)$(LD) $(LDFLAGS) -o $@ $^ $(LIBS)
 	$(Q)$(SIZE) $@
 
+$(BUILD)/firmware-trusted.bin: $(BUILD)/firmware.bin
+	/bin/rm -f $@
+	$(STM32_CUBE_PROGRAMMER)/bin/STM32_SigningTool_CLI -bin $^ -nk -of 0x80000000 -t fsbl -o $@ -hv $(STM32_N6_HEADER_VERSION)
+
 #########################################
 # Rules to generate header files
 

ports/stm32/mboot/adc.c

@@ -1,3 +1,5 @@
 // Include the main ADC driver, so mboot can use adc_config() and adc_config_and_read_u16().
 #include "py/obj.h"
+#if MICROPY_PY_MACHINE_ADC
 #include "../machine_adc.c"
+#endif

ports/stm32/mboot/main.c

@@ -41,6 +41,7 @@
 #include "sdcard.h"
 #include "dfu.h"
 #include "pack.h"
+#include "xspi.h"
 
 // Whether the bootloader will leave via reset, or direct jump to the application.
 #ifndef MBOOT_LEAVE_BOOTLOADER_VIA_RESET
@@ -373,7 +374,7 @@ void SystemClock_Config(void) {
 #elif defined(STM32G0)
 #define AHBxENR IOPENR
 #define AHBxENR_GPIOAEN_Pos RCC_IOPENR_GPIOAEN_Pos
-#elif defined(STM32H7)
+#elif defined(STM32H7) || defined(STM32N6)
 #define AHBxENR AHB4ENR
 #define AHBxENR_GPIOAEN_Pos RCC_AHB4ENR_GPIOAEN_Pos
 #elif defined(STM32H5) || defined(STM32WB)
@@ -424,6 +425,10 @@ void mp_hal_pin_config_speed(uint32_t port_pin, uint32_t speed) {
 #define MBOOT_SPIFLASH2_LAYOUT ""
 #endif
 
+#if defined(STM32N6)
+#define FLASH_LAYOUT_STR "@Internal Flash  " MBOOT_SPIFLASH_LAYOUT MBOOT_SPIFLASH2_LAYOUT
+#else
+
 #if defined(STM32F4) \
     || defined(STM32F722xx) \
     || defined(STM32F723xx) \
@@ -584,12 +589,18 @@ static int mboot_flash_write(uint32_t addr, const uint8_t *src8, size_t len) {
     return 0;
 }
 
+#endif
+
 /******************************************************************************/
 // Writable address space interface
 
 static int do_mass_erase(void) {
+    #if defined(STM32N6)
+    return -1;
+    #else
     // TODO spiflash erase ?
     return mboot_flash_mass_erase();
+    #endif
 }
 
 #if defined(MBOOT_SPIFLASH_ADDR) || defined(MBOOT_SPIFLASH2_ADDR)
@@ -625,7 +636,12 @@ int hw_page_erase(uint32_t addr, uint32_t *next_addr) {
     } else
     #endif
     {
+        #if defined(STM32N6)
+        dfu_context.status = DFU_STATUS_ERROR_ADDRESS;
+        dfu_context.error = MBOOT_ERROR_STR_INVALID_ADDRESS_IDX;
+        #else
         ret = mboot_flash_page_erase(addr, next_addr);
+        #endif
     }
 
     mboot_state_change(MBOOT_STATE_ERASE_END, ret);
@@ -678,9 +694,12 @@ int hw_write(uint32_t addr, const uint8_t *src8, size_t len) {
         ret = mp_spiflash_write(MBOOT_SPIFLASH2_SPIFLASH, addr - MBOOT_SPIFLASH2_ADDR, len, src8);
     } else
     #endif
+    #if !defined(STM32N6)
     if (flash_is_valid_addr(addr)) {
         ret = mboot_flash_write(addr, src8, len);
-    } else {
+    } else
+    #endif
+    {
         dfu_context.status = DFU_STATUS_ERROR_ADDRESS;
         dfu_context.error = MBOOT_ERROR_STR_INVALID_ADDRESS_IDX;
     }
@@ -1509,7 +1528,7 @@ void stm32_main(uint32_t initial_r0) {
     // Make sure IRQ vector table points to flash where this bootloader lives.
     SCB->VTOR = MBOOT_VTOR;
 
-    #if __CORTEX_M != 33
+    #if __CORTEX_M != 33 && __CORTEX_M != 55
     // Enable 8-byte stack alignment for IRQ handlers, in accord with EABI
     SCB->CCR |= SCB_CCR_STKALIGN_Msk;
     #endif
@@ -1539,6 +1558,12 @@ void stm32_main(uint32_t initial_r0) {
     SCB_EnableDCache();
     #endif
 
+    #if defined(STM32N6)
+    LL_PWR_EnableBkUpAccess();
+    initial_r0 = TAMP_S->BKP31R;
+    TAMP_S->BKP31R = 0;
+    #endif
+
     MBOOT_BOARD_EARLY_INIT(&initial_r0);
 
     #ifdef MBOOT_BOOTPIN_PIN
@@ -1748,6 +1773,12 @@ void USB_DRD_FS_IRQHandler(void) {
     HAL_PCD_IRQHandler(&pcd_fs_handle);
 }
 
+#elif defined(STM32N6)
+
+void USB1_OTG_HS_IRQHandler(void) {
+    HAL_PCD_IRQHandler(&pcd_hs_handle);
+}
+
 #elif defined(STM32WB)
 
 void USB_LP_IRQHandler(void) {

ports/stm32/mboot/mphalport.h

@@ -239,3 +239,20 @@ void mp_hal_pin_config_speed(uint32_t port_pin, uint32_t speed);
 #define pin_J13 (GPIOJ_BASE | 13)
 #define pin_J14 (GPIOJ_BASE | 14)
 #define pin_J15 (GPIOJ_BASE | 15)
+
+#define pin_N0  (GPION_BASE | 0)
+#define pin_N1  (GPION_BASE | 1)
+#define pin_N2  (GPION_BASE | 2)
+#define pin_N3  (GPION_BASE | 3)
+#define pin_N4  (GPION_BASE | 4)
+#define pin_N5  (GPION_BASE | 5)
+#define pin_N6  (GPION_BASE | 6)
+#define pin_N7  (GPION_BASE | 7)
+#define pin_N8  (GPION_BASE | 8)
+#define pin_N9  (GPION_BASE | 9)
+#define pin_N10 (GPION_BASE | 10)
+#define pin_N11 (GPION_BASE | 11)
+#define pin_N12 (GPION_BASE | 12)
+#define pin_N13 (GPION_BASE | 13)
+#define pin_N14 (GPION_BASE | 14)
+#define pin_N15 (GPION_BASE | 15)

ports/stm32/mboot/stm32_memory_n6.ld

@@ -0,0 +1,18 @@
+/*
+    Linker script fragment for mboot on an STM32N6xx MCU.
+    This defines the memory sections for the bootloader to use.
+
+    On N6, the hardware bootloader loads the first 512k of external flash into
+    the upper part of SRAM2 AXI S, starting at 0x34180000.  The first 1024 bytes
+    is a header. Then comes the actual code, starting with the vector table.
+*/
+
+MEMORY
+{
+    FLASH_BL (rx)   : ORIGIN = 0x34180400, LENGTH = 31744   /* AXISRAM2_S */
+    RAM (xrw)       : ORIGIN = 0x341e0000, LENGTH = 128K    /* AXISRAM2_S */
+}
+
+/* Location of protected flash area which must not be modified, because mboot lives there. */
+_mboot_protected_flash_start = ORIGIN(FLASH_BL);
+_mboot_protected_flash_end_exclusive = ORIGIN(FLASH_BL) + LENGTH(FLASH_BL);

ports/stm32/mboot/stm32_sections.ld

@@ -33,6 +33,14 @@ SECTIONS
         _etext = .;
     } >FLASH_BL
 
+    /* Secure Gateway stubs */
+    .gnu.sgstubs :
+    {
+        . = ALIGN(4);
+        *(.gnu.sgstubs*)
+        . = ALIGN(4);
+    } >FLASH_BL
+
     /* used by the startup to initialize data */
     _sidata = LOADADDR(.data);