Currently we would like to replace the audio codec of AM335X EVM from TLVAIC3X to ALC5629. So we have to do the migration. Except the codec driver code have to be porting, there are two files need to be changed. codec is an i2c device. This device is registered in board file ( example on […]

Nand flash 要改 layout include/configs/am335x_evm.h 修改 define 這樣可以影響arch/arm/include/asm/arch-am335x/omap_gpmc.h (之前是 arch-omap3/) DRAM 要改 timing arch/arm/include/asm/arch-am33xx/ddr_defs.h arch/arm/cpu/armv7/am33xx/board.c 中會 invoke config_ddr –> config_sdram

In this article we focus on some study notes in linux kernel startup and we mainly focus on start_kernel Specific Arch Initialize in @/init/main.c we could find asmlinkage void __init start_kernel(void) This is the main function to initialize linux kernel. start_kernel() –> setup_arch(&command_line) –> setup_process() will detect the CPU type and invoke high level cpu […]

We could know the MTD structure of AM335x via cat /proc/mtd and we will get dev: size      erasesize name mtd0:  00020000  00020000  “SPL”  mtd1:  00020000  00020000  “SPL.backup1” mtd2:  00020000  00020000  “SPL.backup2” mtd3:  00020000  00020000  “SPL.backup3” mtd4:  001e0000  00020000  “U-Boot” mtd5:  00020000  00020000  “U-Boot Env” mtd6:  00500000  00020000  “Kernel” mtd7:  0f880000  00020000  “File System” […]