what is u-boot configuration macro??

[h=1][/h]hello, I've been working on DE1-SoC board and I tried to transfer data from HPS DDR SDRAM to FPGA on chip memory. And I tried to follow instructions from this link

https://support.criticallink.com/redmine/projects/mityarm-5cs/wiki/important_note_about_fpgahps_sdram_bridge

But problem is, I don't know what exactly this statement means

"Altera has provided the capability to set the configuration bit in step three with a macro command in their (and Critical Link's) u-Boot port. This is accomplished by copying a small routine to on-chip RAM that disables caches and asserts the APPLYCFG bit and then returns operation to the typical DDR space. " (from link above)

first, what does u-boot port means? I found that user can make customized u-boot or preloader but I don't know how to use the 'macro command in u-Boot port'

I already checked if there are related command in current bootloader, there is sort of fpga related command but I still don't get what 'macro command in u-Boot port' means.

secondly, the statements indicates that I have to copy small routine to on chip RAM. Is this means I have to copy machine language directly to RAM?? by initializing RAM with memory init file or something??

I really do need more detailed version of that statement. Specifically can anybody tell me what macro command in u-Boot port means and what copying a small routine to on-chip RAM means??

I do really appreciate any ideas.. thanks in advance