1 How to use and build U-Boot on mx6sabresd
2 -----------------------------------------
4 The following methods can be used for booting mx6sabresd boards:
6 1. Booting from SD card
10 3. Booting via Falcon mode (SPL launches the kernel directly)
13 1. Booting from SD card via SPL
14 -------------------------------
16 mx6sabresd_defconfig target supports mx6q/mx6dl/mx6qp sabresd variants.
20 $ make mx6sabresd_defconfig
24 This will generate the SPL and u-boot.img binaries.
26 - Flash the SPL binary into the SD card:
28 $ sudo dd if=SPL of=/dev/sdX bs=1K seek=1 && sync
30 - Flash the u-boot.img binary into the SD card:
32 $ sudo dd if=u-boot.img of=/dev/sdX bs=1K seek=69 && sync
38 $ make mx6sabresd_defconfig
42 This will generate the SPL and u-boot.img binaries.
44 - Boot first from SD card as shown in the previous section
46 In U-boot change the eMMC partition config:
48 => mmc partconf 2 1 0 0
50 Mount the eMMC in the host PC:
54 - Flash SPL and u-boot.img binaries into the eMMC:
56 $ sudo dd if=SPL of=/dev/sdX bs=1K seek=1 && sync
57 $ sudo dd if=u-boot.img of=/dev/sdX bs=1K seek=69 && sync
59 Set SW6 to eMMC 8-bit boot: 11010110
62 3. Booting via Falcon mode
63 --------------------------
65 $ make mx6sabresd_defconfig
68 This will generate the SPL image called SPL and the u-boot.img.
70 - Flash the SPL image into the SD card:
72 $ sudo dd if=SPL of=/dev/sdX bs=1K seek=1 oflag=sync status=none && sync
74 - Flash the u-boot.img image into the SD card:
76 $ sudo dd if=u-boot.img of=/dev/sdX bs=1K seek=69 oflag=sync status=none && sync
78 Create a partition for root file system and extract it there:
80 $ sudo tar xvf rootfs.tar.gz -C /media/root
82 The SD card must have enough space for raw "args" and "kernel".
83 To configure Falcon mode for the first time, on U-Boot do the following commands:
85 - Setup the IP server:
87 # setenv serverip <server_ip_address>
91 # dhcp ${fdt_addr} imx6q-sabresd.dtb
93 - Download kernel image:
95 # dhcp ${loadaddr} uImage
97 - Write kernel at 2MB offset:
99 # mmc write ${loadaddr} 0x1000 0x4000
101 - Setup kernel bootargs:
103 # setenv bootargs "console=ttymxc0,115200 root=/dev/mmcblk1p1 rootfstype=ext4 rootwait quiet rw"
107 # spl export fdt ${loadaddr} - ${fdt_addr}
109 - Write args 1MB data (0x800 sectors) to 1MB offset (0x800 sectors)
111 # mmc write 18000000 0x800 0x800
113 - Press KEY_VOL_UP key, power up the board and then SPL binary will
114 launch the kernel directly.