Running Linux 6.10 on stm32f429

# Linux 核心專題: Running Linux 6.10 on stm32f429 contributed by < [`hugo0406`](https://github.com/hugo0406) > ## To-do List - TODO: 確保 u-boot 正確編譯、用 st-link 燒錄成功，且在 STM32F429-Discovery 執行 u-boot (可見命令提示) - TODO: 確認 u-boot 支援的 Linux image 格式 (Image, uImage, zImage)，偏好用 XIP - TODO: 在 u-boot 載入 Linux image (from flash)，輸入正確的 boot cmd (boot args) ## STM32F429i-Discovery - STM32F429 MCU (ARM Cortex-M4 up to 180MHz, 2MB internal flash, 256KB internal RAM) - 8MB SDRAM - USB OTG Full-Speed - 2.4" LCD - MEMS motion sensor - STLink/V2 (debugging) - Extension headers ![image](https://hackmd.io/_uploads/HyjgefKE0.png) ### STM32 Reset 參考 STM32F429 的 [Reference Manual](https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf) Boot mode selection pins: BOOT0,BOOT1 CPU reset 後會從這兩根 pin 的狀態來決定哪一塊 memory 當 boot space，STM32F429 選用的 default boot space 是 Main Flash memory | BOOT1 | BOOT0 | Boot Mode | Aliasing | |:-----:|:-----:|:----------------- |:-------- | | X | 0 | Main Flash Memory |Main Flash Memory is selected as the boot space | | 0 | 1 | System Memory |System Memory is selected as the boot space | | 1 | 1 | Embedded SRAM |Embedded SRAM is selected as the boot space | Flash memory 的 start address 是 `0x08000000` 等開機時，會自動將 `0x08000000-0x080FFFFF` 映射到 `0x00000000-0x000FFFFF`，所以將 bin檔燒在 `0x08000000` ，STM32F429 就可以從 `0x00000000` 開始執行 ![image](https://hackmd.io/_uploads/B1dnMN3NA.png) ### Verify if udev rules are set correctly Start by plugging the STLINK device into the usb port, then run `lsusb`. ``` $ lsusb Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 005: ID 06cb:00cb Synaptics, Inc. Bus 001 Device 004: ID 05c8:03d3 Cheng Uei Precision Industry Co., Ltd (Foxlink) HP Wide Vision HD Camera Bus 001 Device 003: ID 0483:3748 STMicroelectronics ST-LINK/V2 Bus 001 Device 006: ID 0bda:b00a Realtek Semiconductor Corp. Realtek Bluetooth 4.2 Adapter Bus 001 Device 002: ID 2717:5023 Xiaomi Inc. MI Wireless Receiver Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub $ ls -l /dev/bus/usb/001/003 crw-rw-rw- 1 root root 189, 2 六 3 03:43 /dev/bus/usb/001/003 ``` There have several files in `/lib/udev/rules.d` directory. The `49-stlinkv2.rules` file contains the following: ``` # STM32 discovery boards, with onboard st/linkv2 # ie, STM32L, STM32F4. # STM32VL has st/linkv1, which is quite different SUBSYSTEMS=="usb", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="3748", \ MODE:="0666", \ SYMLINK+="stlinkv2_%n" # If you share your linux system with other users, or just don't like the # idea of write permission for everybody, you can replace MODE:="0666" with # OWNER:="yourusername" to create the device owned by you, or with # GROUP:="somegroupname" and mange access using standard unix groups. ``` and the `idVendor` of `0483` and `idProduct` of `3748` matches the vendor id from the lsusb output. ### Prerequisites - OpenOCD ```bash git clone git://git.code.sf.net/p/openocd/code openocd cd openocd ./bootstrap ./configure --prefix=/usr/local --enable-stlink echo -e "all:\ninstall:" > doc/Makefile make sudo make install ``` - ~~Set ARM/uClinux Toolchain:~~ - Download [arm-2010q1-189-arm-uclinuxeabi-i686-pc-linux-gnu.tar.bz2](https://sourcery.mentor.com/public/gnu_toolchain/arm-uclinuxeabi/arm-2010q1-189-arm-uclinuxeabi-i686-pc-linux-gnu.tar.bz2) from Mentor Graphics ```bash tar jxvf arm-2010q1-189-arm-uclinuxeabi-i686-pc-linux-gnu.tar.bz2 export PATH=`pwd`/arm-2010q1/bin:$PATH ``` - ARM Cross Compile Toolchain: ```bash sudo apt-get install arm-linux-gnueabi-gcc which arm-linux-gnueabi-gcc export PATH=/usr/bin:$PATH source ~/.bashrc ``` Verify it by checking the installed version : ``` $ arm-linux-gnueabi-gcc --version arm-linux-gnueabi-gcc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0 Copyright (C) 2021 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. ``` - genromfs ```bash sudo apt-get install genromfs ``` - STLINK Tools: `stlink` is an open source toolset to program and debug STM32 devices and boards manufactured by STMicroelectronics. ```bash cd ~ git clone https://github.com/texane/stlink.git cd ./stlink sudo apt-get install libusb-1.0-0-dev sudo apt-get -y install cmake sudo apt-get install libstlink1 make cd build/Release sudo make install ``` To verify the successful installation ```bash $ st-flash invalid command line usage: st-flash [options] read [file] [addr] [size] st-flash [options] write <file> [addr] [size] st-flash [options] write <value> st-flash [options] erase <addr> <size> st-flash [options] reset options: --freq <kHz> Frequency of JTAG/SWD, default 1800kHz. --serial <serial> STLink device to use. --connect-under-reset Pull reset low while connecting. --hot-plug Connect without reset. --reset Reset after writing. --format {binary|ihex} Format of file to read or write. When writing with ihex specifying addr is not needed. --flash <size> Specify size of flash, e.g. 128k, 1M. --area <area> Area to access, one of: main(default), system, otp, option, option_boot_add, optcr, optcr1. --opt Skip writing empty bytes at the tail end. --debug Output extra debug information. --version Print version information. --help Show this help. examples: st-flash --area=option read [file] [size] st-flash --area=option write 0xXXXXXXXX st-flash --area=option_boot_add read st-flash --area=option_boot_add write 0xXXXXXXXX st-flash --area=optcr read st-flash --area=optcr write 0xXXXXXXXX st-flash --area=optcr1 read st-flash --area=optcr1 write 0xXXXXXXXX st-flash --area=otp read <file> st-flash --area=otp write <file> 0xXXXXXXXX ``` `st-info`: a programmer and chip information tool ``` $ st-info --probe Found 1 stlink programmers version: V2J17 serial: 303030303030303030303031 flash: 2097152 (pagesize: 16384) sram: 262144 chipid: 0x419 dev-type: STM32F42x_F43x ``` ### 燒錄測試 STM32F42I-DISCO 內建 ST-LINK/V2，已經包含 ST-Link 了，所以 USB-mini 插上去後就可以直接燒錄，不需要額外的燒錄器。參考 [嵌入式系統建構：開發運作於STM32的韌體程式](https://docs.google.com/document/d/1Ygl6cEGPXUffhTJE0K6B8zEtGmIuIdCjlZBkFlijUaE/edit) 確保能成功將檔案燒錄到開發版上 **blink.c** ```c #define RCC_AHB1_PERI_ENBLR_ADDR (*((volatile unsigned long*) (0x40023800 + 0x30) )) #define GPIO_G_PORTMODE (*((volatile unsigned long*) 0x40021800 )) #define GPIO_G_OUTPUT_TYPE (*((volatile unsigned long*) (0x40021800 + 0x4 ) )) #define GPIO_G_PUPD (*((volatile unsigned long*) (0x40021800 + 0xC ) )) #define GPIO_G_PORT_SETRESET (*((volatile unsigned long*) (0x40021800 + 0x18) )) asm(".word 0x20001000"); asm(".word main "); int main() { int i; RCC_AHB1_PERI_ENBLR_ADDR |= (0x00000001 << 6); /*Enalbe GPIO G clock*/ GPIO_G_PORTMODE |= (0x00000001 << 26 | 0x00000001 << 28); /* Set PG13 PG14 mode to GPIO */ GPIO_G_PORTMODE &= ~(0x00000001 << 27 | 0x00000001 << 29); GPIO_G_OUTPUT_TYPE &= ~(0x00000001 << 13 | 0x00000001 << 14); /*Set PG13 PG14 to push-pull*/ GPIO_G_PUPD |= (0x00000001 << 27 | 0x00000001 << 29); /*Set PG13 PG14 to pull-down*/ while(1) { GPIO_G_PORT_SETRESET = 0x20004000; /*PG13 off, PG14 on*/ for(i = 0 ; i < 100000 ; i++); GPIO_G_PORT_SETRESET = 0x40002000; /*PG14 off, PG13 on*/ for(i = 0 ; i < 100000 ; i++); } return 0; } ``` **Makefile** ```shell CROSS_COMPILE ?= arm-none-eabi- .PHONY: all all: blink.bin blink.o: blink.c $(CROSS_COMPILE)gcc -mcpu=cortex-m4 -mthumb -nostartfiles -c blink.c -o blink.o blink.out: blink.o blink.ld $(CROSS_COMPILE)ld -T blink.ld -o blink.out blink.o blink.bin: blink.out $(CROSS_COMPILE)objcopy -j .text -O binary blink.out blink.bin clean: rm -rf *.o *.out *.bin ``` **blink.ld** ```shell SECTIONS { . = 0x0; .text : { *(.text) } } ``` 執行 `make` : ```shell $ make arm-none-eabi-gcc -mcpu=cortex-m4 -mthumb -nostartfiles -c blink.c -o blink.o arm-none-eabi-ld -T blink.ld -o blink.out blink.o arm-none-eabi-objcopy -j .text -O binary blink.out blink.bin ``` 編譯完後會產生 `blink.out` 及 `blink.bin` ，將 `blink.bin` 燒進 flash ```bash $ st-flash write blink.bin 0x08000000 st-flash 1.8.0-20-gdce9d6e 2024-06-05T14:51:48 INFO common.c: STM32F42x_F43x: 256 KiB SRAM, 2048 KiB flash in at least 16 KiB pages. file blink.bin md5 checksum: b18937a2d44b06afca48131c6027f2, stlink checksum: 0x00002c76 2024-06-05T14:51:48 INFO common_flash.c: Attempting to write 160 (0xa0) bytes to stm32 address: 134217728 (0x8000000) EraseFlash - Sector:0x0 Size:0x4000 -> Flash page at 0x8000000 erased (size: 0x4000) 2024-06-05T14:51:48 INFO flash_loader.c: Starting Flash write for F2/F4/F7/L4 2024-06-05T14:51:48 INFO flash_loader.c: Successfully loaded flash loader in sram 2024-06-05T14:51:48 INFO flash_loader.c: Clear DFSR 2024-06-05T14:51:48 INFO flash_loader.c: enabling 32-bit flash writes 2024-06-05T14:51:48 INFO common_flash.c: Starting verification of write complete 2024-06-05T14:51:48 INFO common_flash.c: Flash written and verified! jolly good! ``` 燒錄後按 RESET 即可看到 `LD3(綠)`、`LD4(紅)` 開始交替閃爍 ### Build - kernel ```bash // 版本太舊 git clone git://git.kernel.org/pub/scm/linux/kernel/git/atorgue/stm32.git git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ``` #### Menuconfig & Kconfig 詳細內容請參閱核心程式碼目錄下的文件 ./Documentation/kbuild/kconfig-language.rst `make tinyconfig` 產生最小的核心，產生的 .config 非常小，不能展示訊息 ```bash make ARCH=arm tinyconfig ``` ``` HOSTCC scripts/kconfig/conf.o HOSTCC scripts/kconfig/confdata.o HOSTCC scripts/kconfig/expr.o LEX scripts/kconfig/lexer.lex.c YACC scripts/kconfig/parser.tab.[ch] HOSTCC scripts/kconfig/lexer.lex.o HOSTCC scripts/kconfig/menu.o HOSTCC scripts/kconfig/parser.tab.o HOSTCC scripts/kconfig/preprocess.o HOSTCC scripts/kconfig/symbol.o HOSTCC scripts/kconfig/util.o HOSTLD scripts/kconfig/conf # # configuration written to .config # Using .config as base Merging ./kernel/configs/tiny.config Value of CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is redefined by fragment ./kernel/configs/tiny.config: Previous value: CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y New value: # CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is not set Value of CONFIG_CC_OPTIMIZE_FOR_SIZE is redefined by fragment ./kernel/configs/tiny.config: Previous value: # CONFIG_CC_OPTIMIZE_FOR_SIZE is not set New value: CONFIG_CC_OPTIMIZE_FOR_SIZE=y Value of CONFIG_KERNEL_GZIP is redefined by fragment ./kernel/configs/tiny.config: Previous value: CONFIG_KERNEL_GZIP=y New value: # CONFIG_KERNEL_GZIP is not set Value of CONFIG_KERNEL_XZ is redefined by fragment ./kernel/configs/tiny.config: Previous value: # CONFIG_KERNEL_XZ is not set New value: CONFIG_KERNEL_XZ=y Value of CONFIG_SLUB_TINY is redefined by fragment ./kernel/configs/tiny.config: Previous value: # CONFIG_SLUB_TINY is not set New value: CONFIG_SLUB_TINY=y # # merged configuration written to .config (needs make) # # # configuration written to .config # ``` 不能使用 tinyconfig ``` make ARCH=arm stm32_defconfig ``` ``` # # configuration written to .config # ``` Menu Config ```bash make ARCH=arm menuconfig ``` When I try to menuconfig, but got some error message ``` make[1]: Entering directory '/home/cychen/stm32/stm32/build/stm32f429' GEN ./Makefile HOSTCC scripts/kconfig/mconf.o <command-line>: fatal error: curses.h: No such file or directory compilation terminated. make[2]: *** [scripts/Makefile.host:108: scripts/kconfig/mconf.o] Error 1 make[1]: *** [/home/cychen/stm32/stm32/Makefile:544: menuconfig] Error 2 make[1]: Leaving directory '/home/cychen/stm32/stm32/build/stm32f429' make: *** [Makefile:150: sub-make] Error 2 ``` `libncurses5-dev need` to be installed before compiling the kernel ```bash sudo apt-get install libncurses5-dev ``` ![image](https://hackmd.io/_uploads/BkrWbsVN0.png) ![image](https://hackmd.io/_uploads/Hk5w2i4VC.png) 編譯核心： ```bash make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- -j4 ``` 編譯完後，可以在核心程式碼目錄下 ./arch/arm/boot/ 看到 `xipImage` :::info xip 代表 execute in place : 程式直接在 flash 上執行，而不必搬到 RAM 上，只有 data 搬到 RAM 。可以減少 memory 的使用，但執行速度較慢。 ::: 查看 xipImage 大小 ``` $ls -lh xipImage -rwxrwxr-x 1 cychen cychen 1.8M 五 30 15:11 xipImage ``` :::danger xipImage 竟然有 1.8MB，幾乎佔了 Flash 大部分的空間，沒有足夠的空間來存放檔案系統，只能保留最基本的功能，盡量減小核心大小 ::: ### Boot loader #### What is a boot loader? When the processor is powered on, the memory doesn't hold an operating system, so special software is needed to bring the OS into memory from the media on which it resides. This software is normally a small piece of code called the boot loader. On a desktop PC, the boot loader resides on the master boot record (MBR) of the hard drive and is executed after the PC's basic input output system (BIOS) performs system initialization tasks. ### U-boot #### Image formats U-Boot is capable of booting images in two formats: - New uImage format (**FIT**) - It allows the use of images with multiple components (several kernels, ramdisks, etc.) :::info FIT 是 flattened image tree 的縮寫，類似於 FDT (flattened device tree)。它利用了Device Tree Source files（DTS）的語法，生成的 image 文件也和 dtb 文件類似（稱作 itb） ::: - Old uImage format - Old image format is based on binary files which can be basically anything, preceded by a special header - Basically, the header defines the following image properties: - Target Operating System - Target CPU Architecture - Compression Type - Load Address - Entry Point - Image Name - Image Timestamp #### U-Boot supports the following image types: With U-Boot, "normal" build targets like "zImage" or "bzImage" are not used. - Standalone Programs - OS Kernel Images - RAMDisk Images - Multi-File Images - Firmware Images - Script files #### Supported devices U-Boot supports the following STMP32 MCU SoCs: - STM32F429 - STM32F469 - STM32F746 - STM32F769 - STM32H743 - STM32H750 The boot chain without `SPL(Secondary Program Loader)` defconfig_file: - stm32f429-discovery_defconfig - stm32f429-evaluation_defconfig - stm32f469-discovery_defconfig - stm32746g-eval_defconfig - stm32f746-disco_defconfig - stm32f769-disco_defconfig - stm32h743-disco_defconfig - stm32h743-eval_defconfig - stm32h750-art-pi_defconfig | **FSBL** | **OS** | | -------- | -------- | | U-boot | Linux | (**Debian based**) Depending on the build targets further packages maybe needed : ``` sudo apt-get install bc bison build-essential coccinelle \ device-tree-compiler dfu-util efitools flex gdisk graphviz imagemagick \ liblz4-tool libgnutls28-dev libguestfs-tools libncurses-dev \ libpython3-dev libsdl2-dev libssl-dev lz4 lzma lzma-alone openssl \ pkg-config python3 python3-asteval python3-coverage python3-filelock \ python3-pkg-resources python3-pycryptodome python3-pyelftools \ python3-pytest python3-pytest-xdist python3-sphinxcontrib.apidoc \ python3-sphinx-rtd-theme python3-subunit python3-testtools \ python3-virtualenv swig uuid-dev ``` 下載 U-boot 原始碼: ```bash git clone git://git.denx.de/u-boot.git cd u-boot ``` 編譯 U-boot: ```bash= make mrproper make stm32f429-discovery_defconfig # make menuconfig make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- -j4 ``` - 第一行是移除之前編譯所產生的文件、配置、備份 - 第二行是生成一個 .config 預設配置 - 第三行是用於更改預設配置，因此它會修改產生的 .config - 第四行直接開始編譯 U-Boot 原始碼，目標檔案是 u-boot.bin - Table. Files generated during U-Boot’s compilation | Filename | Description | |:----------:|:-------------- | | u-boot.map | The symbol map | | u-boot | U-Boot executable in ELF binary format | | u-boot.bin | U-Boot raw binary image, which can be written to the boot storage device | 查看 `u-boot.bin` 大小 ```bash $ ls -lh u-boot.bin -rw-rw-r-- 1 cychen cychen 165K 六 2 21:22 u-boot.bin ``` 燒進 FLASH ```bash $ st-flash write u-boot.bin 0x08000000 st-flash 1.8.0-20-gdce9d6e 2024-06-06T17:01:14 INFO common.c: STM32F42x_F43x: 256 KiB SRAM, 2048 KiB flash in at least 16 KiB pages. file u-boot.bin md5 checksum: 8ca192dd4784d2f0238c045a47fd0, stlink checksum: 0x00d064a8 2024-06-06T17:01:14 INFO common_flash.c: Attempting to write 168912 (0x293d0) bytes to stm32 address: 134217728 (0x8000000) EraseFlash - Sector:0x0 Size:0x4000 -> Flash page at 0x8000000 erased (size: 0x4000) EraseFlash - Sector:0x1 Size:0x4000 -> Flash page at 0x8004000 erased (size: 0x4000) EraseFlash - Sector:0x2 Size:0x4000 -> Flash page at 0x8008000 erased (size: 0x4000) EraseFlash - Sector:0x3 Size:0x4000 -> Flash page at 0x800c000 erased (size: 0x4000) EraseFlash - Sector:0x4 Size:0x10000 -> Flash page at 0x8010000 erased (size: 0x10000) EraseFlash - Sector:0x5 Size:0x20000 -> Flash page at 0x8020000 erased (size: 0x20000) 2024-06-06T17:01:19 INFO flash_loader.c: Starting Flash write for F2/F4/F7/L4 2024-06-06T17:01:19 INFO flash_loader.c: Successfully loaded flash loader in sram 2024-06-06T17:01:19 INFO flash_loader.c: Clear DFSR 2024-06-06T17:01:19 INFO flash_loader.c: enabling 32-bit flash writes 2024-06-06T17:01:23 INFO common_flash.c: Starting verification of write complete 2024-06-06T17:01:26 INFO common_flash.c: Flash written and verified! jolly good! ``` ### Debug - The debug features are used by the debugger host when connecting to and debugging the STM32F4xx MCUs. - Two interfaces for debug are available: • **Serial wire** • **JTAG debug port** #### USART Connection - The STM32F429 Discovery is equipped with various USARTs. USART stands for Universal Synchronous Asynchronous Receiver Transmitter. The USARTs on the STM32F429 support a wide range of serial protocols, the usual asynchronous ones, plus things like IrDA, SPI etc. Since the STM32 works on 3.3V levels, a level shifting component is needed to connect the USART of the STM32F429 to a PC serial port. | STM32 PIN | VCP | | --------- | ---- | | PA9 | USART1_TX | | PA10 | USART1_RX | USB to TTL 接線: - PA9 --> RXD - PA10 --> TXD - GND --> GND ![image](https://hackmd.io/_uploads/SJkzQZmrA.png =375x225) ```shell $ sudo dmesg | grep tty [ 0.134512] printk: console [tty0] enabled [ 5.749521] usb 1-1.4: cp210x converter now attached to ttyUSB0 $ sudo chmod 666 /dev/ttyUSB0 ``` 安裝 PUTTY: ```shell sudo add-apt-repository universe sudo apt install putty ``` 查看 PUTTY版本 ```shell $ putty --version PuTTY: Release 0.76 Build platform: 64-bit Unix (GTK + X11) Compiler: gcc 11.2.0 Compiled against GTK version 3.24.30 Source commit: 1fd7baa7344bb38d62a024e5dba3a720c67d05cf ``` 可以從 [官方文件中](https://github.com/siemens/u-boot/blob/master/drivers/serial/Kconfig) 得知 **Baud Rate** 預設為 `115200` ，**UART number** 預設為 `1` ``` config BAUDRATE int "Default baudrate" default 115200 help Select a default baudrate, where "default" has a driver-specific meaning of either setting the baudrate for the early debug UART in the SPL stage (most drivers) or for choosing a default baudrate in the absence of an environment setting (serial_mxc.c). config CONS_INDEX int "UART used for console" depends on SPECIFY_CONSOLE_INDEX range 0 6 default 1 help Set this to match the UART number of the serial console. ``` 開啟 `putty` ，選擇 serial ， /dev/ttyUSB0 ， Baud rate 選擇 115200 ![image](https://hackmd.io/_uploads/Sk-CMz_SC.png ) 按開發版上的 RESET，可看見 U-Boot 命令提示如下: ``` U-Boot 2024.07-rc3-00020-gea722aa5eb (Jun 09 2024 - 22:25:14 +0800) DRAM: 8 MiB Core: 73 devices, 11 uclasses, devicetree: separate Flash: 2 MiB Loading Environment from Flash... *** Warning - bad CRC, using default environme nt In: serial@40011000 Out: serial@40011000 Err: serial@40011000 U-Boot > help ? - alias for 'help' base - print or set address offset bdinfo - print Board Info structure boot - boot default, i.e., run 'bootcmd' bootd - boot default, i.e., run 'bootcmd' bootelf - Boot from an ELF image in memory bootm - boot application image from memory bootvx - Boot vxWorks from an ELF image cmp - memory compare coninfo - print console devices and information cp - memory copy crc32 - checksum calculation dm - Driver model low level access echo - echo args to console editenv - edit environment variable env - environment handling commands erase - erase FLASH memory exit - exit script false - do nothing, unsuccessfully fdt - flattened device tree utility commands flinfo - print FLASH memory information go - start application at address 'addr' help - print command description/usage iminfo - print header information for application image imls - list all images found in flash imxtract - extract a part of a multi-image itest - return true/false on integer compare loadb - load binary file over serial line (kermit mode) loads - load S-Record file over serial line loadx - load binary file over serial line (xmodem mode) loady - load binary file over serial line (ymodem mode) loop - infinite loop on address range md - memory display mm - memory modify (auto-incrementing address) mw - memory write (fill) nm - memory modify (constant address) panic - Panic with optional message pinmux - show pin-controller muxing printenv - print environment variables protect - enable or disable FLASH write protection reset - Perform RESET of the CPU run - run commands in an environment variable saveenv - save environment variables to persistent storage setenv - set environment variables showvar - print local hushshell variables sleep - delay execution for some time source - run script from memory test - minimal test like /bin/sh timer - access the system timer true - do nothing, successfully version - print monitor, compiler and linker version U-Boot > ``` `version` -> 顯示目前 U-Boot 版本 ``` U-Boot > version U-Boot 2024.07-rc3-00020-gea722aa5eb (Jun 09 2024 - 22:25:14 +0800) ``` `bdinfo` -> 顯示目前板子資訊 ``` U-Boot > bdinfo boot_params = 0x00000000 DRAM bank = 0x00000000 -> start = 0x90000000 -> size = 0x00800000 flashstart = 0x08000000 flashsize = 0x00200000 flashoffset = 0x000241b8 baudrate = 115200 bps relocaddr = 0x907ca000 reloc off = 0x887ca000 Build = 32-bit fdt_blob = 0x905c2cb0 new_fdt = 0x905c2cb0 fdt_size = 0x00005220 lmb_dump_all: memory.cnt = 0x1 / max = 0x10 memory[0] [0x90000000-0x907fffff], 0x00800000 bytes flags: 0 reserved.cnt = 0x1 / max = 0x10 reserved[0] [0x905be9a8-0x907fffff], 0x00241658 bytes flags: 0 devicetree = separate arch_number = 0x00000000 TLB addr = 0x907f0000 irq_sp = 0x905c2ca0 sp start = 0x905c2c90 Early malloc usage: f40 / 2000 ``` 製作 uImage ``` ``` git@github.com:fdu/STM32F429I-disco_Buildroot.git ## Reference 1. [build-linux-kernel](https://phoenixnap.com/kb/build-linux-kernel) 2. [Reference Manual](https://www.st.com/content/ccc/resource/technical/document/reference_manual/3d/6d/5a/66/b4/99/40/d4/DM00031020.pdf/files/DM00031020.pdf/jcr:content/translations/en.DM00031020.pdf) 3. [STM32](https://elinux.org/STM32) 4. [uClinux](https://community.intel.com/t5/FPGA-Wiki/UClinux/ta-p/735614) 5. [stlink Tools Tutorial](https://github.com/stlink-org/stlink/blob/testing/doc/tutorial.md) 6. https://www.tw511.com/a/01/54206.html 7. [Building Embedded Linux Systems](https://www.esys.ir/Files/Ref_Books/Linux/esys.ir_Building.Embedded.Linux.Systems.2nd.Edition.pdf) 8. [uboot](http://www.denx.de/wiki/UBoot) 9. [device tree](https://reurl.cc/9vYyy8) 10. [initrd](https://zh.wikipedia.org/zh-tw/Initrd) 11. https://github.com/u-boot/u-boot/tree/master/board/st/stm32f429-discovery 12. https://github.com/u-boot/u-boot/blob/master/doc/board/st/stm32_MCU.rst 13. https://www.triplespark.net/elec/pdev/arm/stm32.html 14. https://www.youtube.com/watch?v=Hxcyn9P7d88 15. https://www.youtube.com/watch?v=dMVFaRuZICI 16. https://stackoverflow.com/questions/52385728/using-putty-to-print-from-stm32 17. https://en.devrelerim.com/2022/11/stm32f4-discovery-as-st-link-programmer.html#google_vignette 18. https://en.devrelerim.com/2022/11/stm32f4-discovery-as-st-link-programmer.html 19. https://www.twblogs.net/a/5baffff92b7177781a0f8d7d 20. https://pominglee.blogspot.com/2013/12/uboot.html

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