[PATCH] Enable MIPI filtering by DT on i.MX8M*

Krzysztof Hałasa khalasa at piap.pl
Thu May 29 02:25:08 PDT 2025


Hi Sébastien,

Sébastien Szymanski <sebastien.szymanski at armadeus.com> writes:

> On i.MX8MM mipi_csi is at 32e30000. NXP kernel (6.12.3) with ov5640 camera:
>
> # devmem 0x32E30000 32
> 0x03060301

Thanks a lot. So at least the version register is the same as on
i.MX8MP.
I wonder if you could test if the CSIC possibly supports filtering by
DT.

How would such a test be performed?

Maybe: while streaming (otherwise the system may lock up):

I assume 'devmem 0x32E30004 32' shows 0x4305.
# devmem 0x32E30004 32 0x14705

and:
- does it change anything? If the streaming stops, you may try
  restarting and writing with devmem again - writing to this register
  directly frequently stops streaming on my 8MP.

- what does the register contain after write?

- you may also try:
  # devmem 0x32E30004 32 0xfffffffd
  # devmem 0x32E30004 32

On i.MX8MP the above returns:
# ./devmem write32 0x32Ex0004 0xfffffffd
# ./devmem read32 0x32Ex0004
0x0000FF05
(and the streaming still works, usually).

The above is not a very good test, I admit, but it may show 8MM really
doesn't have those/that bit.

TIA.
-- 
Krzysztof "Chris" Hałasa

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