Understand the mysterious face of uboot

The purpose of this "Understanding the Mysterious Face of Uboot" course is to help you understand the concepts and related hardware involved in the system startup part of embedded development step by step through the analysis of the entire process of an excellent bootloader software. principle. Including CP15, UART, DDR2 and other device information that must be mastered for system startup.

• Chapter 1：u-boot version selection (10 minutes and 23 seconds)

• Chapter 2：Exception vector table of u-boot, V210 startup mechanism principle (18 minutes and 49 seconds)

• Chapter 3：Use objdump disassembly to view u-boot's header code and exception vector processing (19 minutes and 53 seconds)

• Chapter 4：Expansion of macros such as ENTRY, setting of CPSR register (20 minutes and 14 seconds)

• Chapter 5：CP15 coprocessor basics, VBAR exception vector table base address mapping (9 minutes and 48 seconds)

• Chapter 6：cpu_init_cp15 subprocess analysis: cache operation (22 minutes and 55 seconds)

• Chapter 7：cpu_init_cp15 subprocess analysis (continued): branch prediction, MMU operation (19 minutes and 20 seconds)

• Chapter 8：cpu_initcrit sub-process analysis, Experiment 1: Modify the u-boot source code to use LED lights to display the running status (20 minutes and 14 seconds)

• Chapter 9：Experiment 1 (continued): Circuit analysis of GPIO input and output (20 minutes and 12 seconds)

• Chapter 10：Experiment 1 (continued): The principle of making u-boot burning image, mkv210 source code analysis (21 minutes and 1 seconds)

• Chapter 11：Experiment 1 (continued): Use the hexdump tool to analyze the hexadecimal code of the image (20 minutes and 24 seconds)

• Chapter 12：Overview of compilation, linking, and assembly processes (19 minutes and 52 seconds)

• Chapter 13：Experiment 2: Write your own boot program: myboot (19 minutes and 26 seconds)

• Chapter 14：Experiment 2 (continued): Link principle of two or more files (20 minutes and 7 seconds)

• Chapter 15：Experiment 2 (continued): Disassemble and analyze your own myboot (20 minutes and 16 seconds)

• Chapter 16：Experiment 2 (continued): Use Makefile to automatically compile myboot (21 minutes and 21 seconds)

• Chapter 17：Experiment 2 (continued): Improving our Makefile (20 minutes and 24 seconds)

• Chapter 18：Experiment 2 (continued): Automation variables in Makefile (21 minutes and 26 seconds)

• Chapter 19：Determine chip model and reset mode (20 minutes and 53 seconds)

• Chapter 20：IO retention, reset mode judgment, interrupt initialization (20 minutes and 28 seconds)

• Chapter 21：UART initialization and asynchronous communication principles (20 minutes and 32 seconds)

• Chapter 22：UART analysis 1 (20 minutes and 32 seconds)

• Chapter 23：UART analysis 2 (20 minutes and 18 seconds)

• Chapter 24：UART analysis 3 (20 minutes and 24 seconds)

• Chapter 25：UART Analysis 4 (18 minutes and 59 seconds)

• Chapter 26：Experiment 3: Use UART to display data in a specified memory (24 minutes and 11 seconds)

• Chapter 27：Basic principles of DDR memory 1 (19 minutes and 45 seconds)

• Chapter 28：Basic principles of DDR memory 2 (20 minutes and 14 seconds)

• Chapter 29：Basic principles of DDR memory 3 (20 minutes and 11 seconds)

• Chapter 30：Hardware connection of DDR memory on V210 open board 1 (20 minutes and 21 seconds)

• Chapter 31：Hardware connection of DDR memory on V210 open board 2 (19 minutes and 23 seconds)

• Chapter 32：Internal structure of DDR2-Device 1 (20 minutes and 29 seconds)

• Chapter 33：Internal structure of DDR2-Device 2 (21 minutes and 9 seconds)

• Chapter 34：DDR2-operating finite state machine (21 minutes and 5 seconds)

• Chapter 35：DDR2 MRS and EMRS registers (21 minutes and 20 seconds)

• Chapter 36：DDR2 read and write timing (22 minutes and 24 seconds)

• Chapter 37：DDR2 read and write timing x (20 minutes and 45 seconds)

• Chapter 38：DDR2 initialization code analysis 1 (18 minutes and 46 seconds)

• Chapter 39：DDR2 initialization code analysis 2 (20 minutes and 8 seconds)

• Chapter 40：DDR2 initialization code analysis 3 (24 minutes and 26 seconds)

• Chapter 41：DDR2 initialization code analysis 4 (20 minutes and 28 seconds)

• Chapter 42：DDR2 initialization code analysis 5 (19 minutes and 52 seconds)

• Chapter 43：DDR2 initialization code analysis 6 (21 minutes and 24 seconds)

• Chapter 44：DDR2 initialization code analysis 7 (19 minutes and 49 seconds)

• Chapter 45：DDR2 initialization code analysis 8 (20 minutes and 41 seconds)

• Chapter 46：DDR2 initialization code analysis 9 (20 minutes and 32 seconds)

• Chapter 47：DDR2 initialization code analysis 10 (20 minutes and 25 seconds)

• Chapter 48：Write your own DDR initialization code1 (20 minutes and 50 seconds)

• Chapter 49：Write your own DDR initialization code 2 (20 minutes and 11 seconds)

• Chapter 50：board_init_f function analysis 1 (22 minutes and 20 seconds)

• Chapter 51：board_init_f function analysis 2 (19 minutes and 30 seconds)

• Chapter 52：mmc_relocate analysis (19 minutes and 49 seconds)

• Chapter 53：Experiment 5: Move u-boot.bin from SD card to DDR memory (21 minutes and 16 seconds)

• Chapter 54：Experiment 5: Move u-boot.bin from SD card to DDR memory 2 (20 minutes and 21 seconds)

• Chapter 55：Analysis of link mirror structure of u-boot (21 minutes and 34 seconds)

• Chapter 56：board_init_f function analysis 3 (20 minutes and 56 seconds)

• Chapter 57：board_init_f function analysis 4 (20 minutes and 26 seconds)

• Chapter 58：board_init_f function analysis 5 (21 minutes and 11 seconds)

• Chapter 59：board_init_f function analysis 6 (20 minutes and 4 seconds)

• Chapter 60：board_init_f function analysis 7 (20 minutes and 2 seconds)

• Chapter 61：Bootstrap implementation of u-boot (19 minutes and 41 seconds)

• Chapter 62：relocate_code assembly bootstrap code analysis (20 minutes and 52 seconds)

• Chapter 63：The second half of board-level initialization: bord_init_r function analysis 1 (20 minutes and 2 seconds)

• Chapter 64：The second half of board-level initialization: bord_init_r function analysis 2 (21 minutes and 59 seconds)

• Chapter 65：The second half of board-level initialization: bord_init_r function analysis 3 (20 minutes and 38 seconds)

• Chapter 66：The second half of board-level initialization: bord_init_r function analysis 4 (20 minutes and 43 seconds)

• Chapter 67：Jump to the main loop, main_loop (19 minutes and 54 seconds)

• Chapter 68：Main loop analysis: The principle of u-boot parsing the terminal input command line (21 minutes and 8 seconds)

• Chapter 69：Main loop analysis: command execution implementation of u-boot (13 minutes and 6 seconds)

• Chapter 70：bootm startup process analysis 1 (20 minutes and 50 seconds)

• Chapter 71：bootm startup process analysis 2 (19 minutes and 58 seconds)

• Chapter 72：bootm startup process analysis 3 (22 minutes and 17 seconds)

• Chapter 73：bootm startup process analysis 4 (20 minutes and 46 seconds)