[PATCH] ls1028a: hdp: Add config support for HDP firmware loading

[Michael Walle]

Am 2022-05-10 19:47, schrieb Vladimir Oltean:
> On Tue, May 10, 2022 at 04:18:32PM +0200, Michael Walle wrote:
>> > From: Alison Wang <alison.wang at nxp.com>
>> >
>> > This patch adds config support for HDP firmware loading on LS1028A.
>> 
>> FWIW, I really don't like this as this is just for a downstream 
>> kernel.
> 
> This => what? I only see a config option. I searched the list and the
> source code for CONFIG_VIDEO_LS_HDP_LOAD and I don't see any user...

You are right, I didn't actually notice that. The whole loading thing
[1] is missing.

>> For the upstream kernel the firmware should be loaded by the kernel 
>> itself.
> 
> In principle I agree.
> 
>> But unfortunately, there is no development there. (I have some half
>> baked patches though and can confirm, that firmware loading is working
>> from linux). Instead of this I'd like to see some work to support the
>> DP PHY in upstream linux as this is really the last missing piece to
>> get graphics working.
> 
> It is? What did I miss?

I don't know? etnaviv is working [2 and more], mesa will be working soon
[3]. mali-dp500 should have been working all the time. So only the 
output
path is missing. If you are interested, this [4] is my take on the
support, which is actually working. But I haven't found any time to look
at it again. And I'm missing any documentation, so most information was
found out by educated guesses and comparing to the downstream driver.
I'd greatly appreciate any help ;)

[1] 
https://source.codeaurora.org/external/qoriq/qoriq-components/u-boot/tree/drivers/video/nxp/layerscape?h=integration
[2] 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/gpu/drm/etnaviv?id=12495f4eb298963565e0bdd37d8096ab1136d89f
[3] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9255
[4] https://github.com/mwalle/linux/tree/feature-cdns-phy

-michael