We have a custom board design based on the iMX6 Dual (MCIMX6D6AVT10AD), and I've reached a perplexing issue while trying to bring up the RGMII interface. Configuring any of the following pins causes some of the SD3 pins to no longer function properly:
Since my root filesystem is on an SD card plugged in to SD3, it's much more difficult to debug this issue, although I do have a JTAG probe to read registers if necessary.
I've looked through the TRM a fair bit, but the only common thread I can find between the RGMII pins and the SD3 pins is that they originate from the same clock source. Does any one else have any further insight in to what might be causing this?
Also, I noticed that the Wandboard Dual uses both these interfaces in pretty much the same exact fashion that I would like, but uses the iMX6 DualLite: Is there any appreciable difference between the SOC I'm using the DualLite?
Other details that might be relevant:
- Linux kernel with only board specific changes based on imx_3.10.17_1.0.0_ga
- Barebox boot loader based upon v2015.06.0
- Using 4-bit SDHC on SD3