Hi Richard,

Thanks for the patch. Please always add linux-imx@nxp.com mailing
list for imx related patches. I missed it.

Few comments inline.

Please also update in a separate patch attached to this series
the devictree bindings doc Documentation/devicetree/bindings/mailbox/fsl,mu.txt
by adding description for mx7ulp-mu

<snip>

> There is a version1.0 MU on i.MX7ULP platform.

space between version and 1.0

> One new version ID register is added, and it's offset is 0.
> TRn registers are defined at the offset 0x20 ~ 0x2C.
> RRn registers are defined at the offset 0x40 ~ 0x4C.
> SR/CR registers are defined at 0x60/0x64.
> Extend this driver to support it.

Do you have a little bit of history about MU versioning? So there was:

* version 0.5 on i.MX6-es
* version 1.0 on i.MX7ULP

Next, is this 1.0 compatbile with i.MX8 right?

Also, can you please rebase your patch on my 2 bugfixes attached?

thanks,
Daniel.