Neha Malcom Francis <n-francis@ti.com>
<IMAGE_FLAG> is a value that specifies the type of the image to generate OR the action the image generation tool will take. Valid values are:
| X-LOADER | Generates an image for NOR or QSPI boot modes |
| MLO | Generates an image for NOR or QSPI boot modes |
| ULO | Generates an image for USB/UART peripheral boot modes |
<INPUT_FILE> is the full path and filename of the public world boot loaderbinary file (for this platform, this is always u-boot-spl.bin).
<OUTPUT_FILE> is the full path and filename of the final secure image. The output binary images should be used in place of the standard non-secure binary images (see the platform-specific user's guides and releases notes for how the non-secure images are typically used)
| u-boot-spl_HS_SPI_X-LOADER | boot image for SD/MMC/eMMC. This image is copied to a file named MLO, which is the name that the device ROM bootloader requires for loading from the FAT partition of an SD card (same as on non-secure devices) |
| u-boot-spl_HS_ULO | boot image for USB/UART peripheral boot modes |
| u-boot-spl_HS_X-LOADER | boot image for all other flash memories including QSPI and NOR flash |
<SPL_LOAD_ADDR> is the address at which SOC ROM should load the <INPUT_FILE>
It is possible, depending on SYSBOOT configuration to boot from the eMMC boot partitions using (name depending on documentation referenced) Alternative Boot operation mode or Boot Sequence Option 1/2. In this example we load MLO and u-boot.img from the build into DDR and then use 'mmc bootbus' to set the required rate (see TRM) and 'mmc partconfig' to set boot0 as the boot device.
bash =>
setenv autoload no usb start dhcp mmc dev 1 1 tftp ${loadaddr} dra7xx/MLO mmc write ${loadaddr} 0 100 tftp ${loadaddr} dra7xx/u-boot.img mmc write ${loadaddr} 300 400 mmc bootbus 1 2 0 2 mmc partconf 1 1 1 0 mmc rst-function 1 1
Build the patched U-Boot and load MLO/u-boot.img.
Boot from another medium like MMC
bash
=> mmc dev 0 mmc0 is current device => fatload mmc 0 0x82000000 MLO reading MLO 55872 bytes read in 8 ms (6.7 MiB/s) => fatload mmc 0 0x83000000 u-boot.img reading u-boot.img 248600 bytes read in 19 ms (12.5 MiB/s)
Commands to erase/write u-boot/MLO to flash device
bash
=> sf probe 0 SF: Detected S25FL256S_64K with page size 256 Bytes, erase size 64 KiB, total 32 MiB, mapped at 5c000000 => sf erase 0 0x10000 SF: 65536 bytes @ 0x0 Erased: OK => sf erase 0x20000 0x10000 SF: 65536 bytes @ 0x20000 Erased: OK => sf erase 0x30000 0x10000 SF: 65536 bytes @ 0x30000 Erased: OK => sf erase 0x40000 0x10000 SF: 65536 bytes @ 0x40000 Erased: OK => sf erase 0x50000 0x10000 SF: 65536 bytes @ 0x50000 Erased: OK => sf erase 0x60000 0x10000 SF: 65536 bytes @ 0x60000 Erased: OK => sf write 82000000 0 0x10000 SF: 65536 bytes @ 0x0 Written: OK => sf write 83000000 0x20000 0x60000 SF: 393216 bytes @ 0x20000 Written: OK
Next, set sysboot to QSPI-1 boot mode(SYSBOOT[5:0] = 100110) and power on. ROM should find the GP header at offset 0 and load/execute SPL. SPL then detects that ROM was in QSPI-1 mode (boot code 10) and attempts to find a U-Boot image header at offset 0x20000 (set in the config file) and proceeds to load that image using the U-Boot image payload offset/size from the header. It will then start U-Boot.