fdisk -l Disk /dev/sdc: 7.3 GiB, 7822376960 bytes, 15278080 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000 Device Boot Start End Sectors Size Id Type /dev/sdc1 8192 15278079 15269888 7.3G b W95 FAT32The first partition begins after skipping 4M of space, so we have plenty of room before the partition for U-boot. Not that we care all that much if all we want to do is play with U-boot. The Orange Pi boot loader ignores the partition table and just looks for the SPL a fixed distance into the SD card. We install U-boot via:
dd if=u-boot-sunxi-with-spl.bin of=/dev/sdc bs=1024 seek=8 435+1 records in 435+1 records out 445597 bytes (446 kB, 435 KiB) copied, 0.000751595 s, 593 MB/sThen I carefully insert the card into my Orange Pi PC plus and apply power. It works! I want it to enter the U-boot command line by default. Printenv shows the full set of environment setting for U-boot. I change the setting for bootcmd as follows:
printenv bootcmd=run loadsplash; run distro_bootcmd ... setenv bootcmd bootp saveenv Saving Environment to MMC... Writing to MMC(0)... doneThis suffices for now for some testing I want to do.
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