[U-Boot] Enabling ARM DCache (and MMU setup) in U-Boot

Hi all, I would like to eneble DCache in U-Boot, because peripheral register R/W and SDRAM R/W is extremely slow on my platform, so booting Linux image takes unexceptable long time. But apparently for ARM, MMU setup is needed first. Now, I did not find example on any presented ARM platforms included in U-Boot.

Did somebody maybe suceeded on doing this and where can I find some C/ASM examples how to set up MMU and enable DCache for ARM?

Best regards, Drasko