my custom board with 2G DRAM now runs very well, see how to change ddr to 2G on u-boot 2015.04
next i need to make a u-boot for mfgtools.
my android is 5.1.1, the mfgtools is different from previous versions, i followed thd document <Manufacturing Tool V2 Linux or Android Firmware Development Guide V2.docx> to modify the header file mx6sabresd.h (my board based on sabresd-6q), added the below code:
#define CONFIG_MFG
#define CONFIG_CMDLINE_TAG
#define CONFIG_REVISION_TAG
#define CONFIG_SETUP_MEMORY_TAGS
#define CONFIG_INITRD_TAG
#undef CONFIG_BOOTDELAY
#define CONFIG_BOOTDELAY 0
#define CONFIG_ENV_IS_NOWHERE 1
#undef CONFIG_BOOTARGS
#undef CONFIG_BOOTCOMMAND
#define CONFIG_BOOTARGS "console=ttymxc0,115200 rdinit=/linuxrc g_mass_storage.stall=0 g_mass_storage.removable=1 " \
"g_mass_storage.idVendor=0x066F g_mass_storage.idProduct=0x37FF g_mass_storage.iSerialNumber="" enable_wait_mode=off"
#define CONFIG_BOOTCOMMAND "bootz 0x12000000 0x12c00000 0x18000000"
#undef CONFIG_EXTRA_ENV_SETTINGS
#define CONFIG_EXTRA_ENV_SETTINGS \
"splashpos=m,m\0" \
"fdt_high=0xffffffff\0" \
"initrd_high=0xffffffff\0" \
"bootcmd_mfg=bootz 0x12000000 0x12c00000 0x18000000\0"
compile , got u-boot.imx, this bin file ready for mfgtools, i reuse original zImage and initramfs and dtb files, just replace the u-boot located mfgtools\Profiles\Linux\OS Firmware\firmware, the mfgtools burns roms for my custom board successfully. everything runs good.