1 How to use and build U-Boot on mx6sabreauto 2 ------------------------------------------- 3 4 mx6sabreauto_defconfig target supports mx6q/mx6dl/mx6qp sabreauto variants. 5 6 In order to build it: 7 8 $ make mx6sabreauto_defconfig 9 10 $ make 11 12 This will generate the SPL and u-boot.img binaries. 13 14 - Flash the SPL binary into the SD card: 15 16 $ sudo dd if=SPL of=/dev/sdX bs=1K seek=1 && sync 17 18 - Flash the u-boot.img binary into the SD card: 19 20 $ sudo dd if=u-boot.img of=/dev/sdX bs=1K seek=69 && sync 21 22 Booting via Falcon mode 23 ----------------------- 24 25 Write in mx6sabreauto_defconfig the following define below: 26 27 CONFIG_SPL_OS_BOOT=y 28 29 In order to build it: 30 31 $ make mx6sabreauto_defconfig 32 33 $ make 34 35 This will generate the SPL image called SPL and the u-boot.img. 36 37 - Flash the SPL image into the SD card: 38 39 $ sudo dd if=SPL of=/dev/sdb bs=1K seek=1 && sync 40 41 - Flash the u-boot.img image into the SD card: 42 43 $ sudo dd if=u-boot.img of=/dev/sdb bs=1K seek=69 && sync 44 45 Create a FAT16 boot partition to store uImage and the dtb file, then copy the files there: 46 47 $ sudo cp uImage /media/boot 48 49 $ sudo cp imx6dl-sabreauto.dtb /media/boot 50 51 Create a partition for root file system and extract it there: 52 53 $ sudo tar xvf rootfs.tar.gz -C /media/root 54 55 The SD card must have enough space for raw "args" and "kernel". 56 To configure Falcon mode for the first time, on U-Boot do the following commands: 57 58 - Load dtb file from boot partition: 59 60 # load mmc 0:1 ${fdt_addr} imx6dl-sabreauto.dtb 61 62 - Load kernel image from boot partition: 63 64 # load mmc 0:1 ${loadaddr} uImage 65 66 - Write kernel at 2MB offset: 67 68 # mmc write ${loadaddr} 0x1000 0x4000 69 70 - Setup kernel bootargs: 71 72 # setenv bootargs "console=ttymxc3,115200 root=/dev/mmcblk0p1 rootfstype=ext4 rootwait quiet rw" 73 74 - Prepare args: 75 76 # spl export fdt ${loadaddr} - ${fdt_addr} 77 78 - Write args 1MB data (0x800 sectors) to 1MB offset (0x800 sectors) 79 80 # mmc write 18000000 0x800 0x800 81 82 - Restart the board and then SPL binary will launch the kernel directly. 83
