06-24-2020 01:20 PM
We're trying to fit the linux image into flash. The bitfile is just less than 16MB and the linux image (image.elf) file is about 20 MB. That exceeds the 32MB (128 Mb) of U35. How can I store the Linux image in the second QSPI flash device (U36) and boot from it?
0x0000000 – 0x0FFFFFF : bit file (16MB)
0x1000000 – 0x1FFFBFF : linux image (~16MB)
0x1FFFC00 – 0x1FFFFFF : image_desc.bin
06-29-2020 12:15 PM - edited 06-29-2020 12:16 PM
If you have ethernet, then you can boot the kernel over tftp from uboot. This would be the easiest way, as it doesnt require any HW/SW changes
06-29-2020 01:11 PM
Thanks - that would work for development, but we are trying to send MCS files to customers for evaluation of our IP cores, and we don't want them to have to set up the enviromment for TFTP for a demo. Is there a way to get to the second flash chip? Maybe download a partial MCS with some code (modified FSBL?) that copies from the first flash to the second, making room to overwrite the first flash with the bit file...? Then boot PetaLinux from the second flash?
My assumption is that the JTAG cannot access the second flash. Is that correct? They are both wired directly to the FPGA, so why is there a limitation to the first flash?