I was trying to get the PLL2 spread spectrum feature enabled on my i.MX6D following this article:
Using the original code from the article I run into boot problems where u-boot did not come up at all. Finally I found that the used BootROM plugin technique did not work (ony my system) and I could fix the issues. I want to supply my changed file to all of you maybe having the same problems. This needs to be placed in the board specific u-boot folder.
Keep in mind that the used HW initialisation (especially the DDR3 RAM section) is for my system setup and needs to be modified to fit to your system. Before enabling the spread spectrum and therefore changing to plugin mode I used to have a DCD style flash_header.S. To "copy" the prooven DCD settings I simply used the asm commands to store the register values in the plugin code.
Original Attachment has been moved to: flash_header.S.txt.zip