mx6ull DDR3 script generation aid uboot problem

[tkl]

Hi,

for a custom board I have to set up the DDR3 RAM parameters. As a test I tried to run through the process with the i.MX6ULL DevBoard. I used the script aid to get the RealView.inc file with the values for the RAM which is mounted on the ULL Devboard.

As I understand, I now have to use the DDR Stress Test Tool to get the missing calibration values. To do this, I want to use the UBoot method. For this I am using the UBoot v2018.03 and am setting the values which I got from the script aid tool in the file imximage.cfg for the devboard. With these values I build the UBoot and try to tun it on the DevBoard. The problem is, that the UBoot isn't starting at all with these values. It works with the USB method but since I have no USB or JTAG on the custom board, I have to use the UBoot method. Has anyone an idea what I might be doing wrong? I attach the realview.inc I am getting from the script aid.

I can build and use the UBoot with the parameters that come for the devboard without problems. With this I can run the DDR Stess Test Tool but this won't help me with the custom board.

[tkl · Accepted solution]

If anyone has this problem, I found a solution. To get the U-Boot working without calibration on the DevBoard, an initial DQS Gating delay has to be set. For me it worked to set

DATA 4 0x021B083C 0x41000100

to fire up the U-Boot and get the calibrated vales which match quit good with the original values provided in the U-Boot sources.