Crash in ddr2_sdram_initialize

[tksprague]

During bring-up of a SAM9X60-Curiosity board, we found that the delay on line 960 of driver/ddramc.c was not long enough. Recognized the problem by stepping through and having everything work OK, while straight run of the bootloader did not work.

We duplicated line 960 to double the delay, and things run OK now.

Recommend double-checking udelay, and specs for the DDR2 SDRAM in this chip, to make sure the delays are appropriate.

One note, another developer with the same repo (possibly older commit) and same board did not encounter this problem.

We are working with the commit on 30-Sept, fff35f3

[tksprague]

Still encountering similar crashes within the same routine. Still suspect timing issues, a lot of comments right before udelay suggest longer delays than are being used.

BTW, the config we used is sam9x60_curiosity_bkptnone_defconfig