IMX8M Problem with 1.8 eMMC

[awaken]

Hello,

we have a small firmware for the Cortex-A53 which handles eMMC access. Until nowhave we tested this functionally without problems. Now there is a new board (8MMINI-BB) which has an SDINBDG4 eMMC attached to SDHC3 Interface. Executing CMD0 works so far (but CMD1 fails.

It fails at the "command complete" polling (see Interrupt Status Register) because the command never completes. But we can see in the digitalanalyzer that the eMMC-Device is responding.

Note: before CMD1  ~90 clock cycles and CMD0 is send

My question is: What can be the cause of this behaviour. I guess is has something to do with the 1.8V Bus voltage.

[igorpadykov]

Hi Martin

>Now there is a new board (8MMINI-BB) which has an SDINBDG4 eMMC attached to SDHC3 Interface.

board (8MMINI-BB) has not emmc, it has MicroSD attached to SDHC2 (p.10 SPF-31407).

i.MX 8M Mini Evaluation Kit LPDDR4 Design Files 

i.MX8M Mini SOM Board has emmc  attached to SDHC3 Interface.

It can be tested using Demo Images and documentation from link

Embedded Linux for i.MX Applications Processors | NXP 

i.MX8M EVK has emmc (p.9 SPF-38820)  attached to SDHC1

Design Files for the i.MX 8M Evaluation Kit (EVKB)

In general CMD1 (read Operating Conditions Register, used for eMMC initialization) may fail 

due to voltage incompatibility, detailed description can be found in emmc specification.

Standards & Documents Search | JEDEC 

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------