i'm struggling with my IMX6SX based platform.
I'm using Yocto with kernel 3.14.28+g91cf351.
On my device I monted a eMMC 4.41 compliance and I'm able to make it working with DDR and 4 bits data bus.
I'm trying to enable 8bit data bus but I found out that the kernel fails to request that type of bus and switch back automatically to 4 bits.
Into dts bus-width is correctly set to 8.
I found out that the kernel drvier receive error -84 into data.err when try top read CSD data using function mmc_send_cxd_data (code in mmc_ops.c) called by mmc_init_card (in mmc.c) where the DDR wide bus activiation is performed (around line 1642).
Are there known bugs on this matter?