How to use ecspi slave in DMA mode on i.MX6ULL

[chenxibing1]

hi!

    I need to use ecspi slave in DMA mode on i.MX6ULL.Kernel version is 4.14.98 and it doesn`t use DMA in slave mode.Pls if there is anything that can help me with documentation or patches.

    THANKS！

[AldoG · Accepted solution]

Hello,

Unfortuately the ECSPI slave driver is not using DMA, but PIO. Although DMA is defined in dts file, it is for master mode.

We do have an App note that may help to enable this, it is for the i.MX8MM but it is the same ECSPI module present in the i.MX6ULL
https://www.nxp.com/docs/en/application-note/AN13633.pdf

Best regards,
Aldo.

[chenxibing1]

Hi,

   Thank you so much,Aldo.

    I see point 5.2.2  that there is a patch to support 4-byte aligned DMA in slave mode.Could you give me this patch?

   THANKS!

    Best wishes,

    Chen.

[AldoG]

Hello,

yes, please download from here:
https://www.nxp.com/docs/en/application-note-software/AN13633SW.zip

Best regards,
Aldo