[PATCH v3 1/3] drm/loongson: Add DRM Driver for Loongson 7A1000 bridge chip

[Daniel Vetter]

On Fri, Jul 23, 2021 at 07:22:46PM +0200, Sam Ravnborg wrote:
> On Fri, Jul 23, 2021 at 10:57:56AM +0200, Daniel Vetter wrote:
> > On Fri, Jul 23, 2021 at 11:12:49AM +0800, lichenyang wrote:
> > > From: Chenyang Li <lichenyang at loongson.cn>
> > > 
> > > This patch adds an initial DRM driver for the Loongson LS7A1000
> > > bridge chip(LS7A). The LS7A bridge chip contains two display
> > > controllers, support dual display output. The maximum support for
> > > each channel display is to 1920x1080 at 60Hz.
> > > At present, DC device detection and DRM driver registration are
> > > completed, the crtc/plane/encoder/connector objects has been
> > > implemented.
> > > On Loongson 3A4000 CPU and 7A1000 system, we have achieved the use
> > > of dual screen, and support dual screen clone mode and expansion
> > > mode.
> > > 
> > > v9:
> > > - Optimize the error handling process.
> > > - Remove the useless flags parameter.
> > > - Fix some incorrect use of variables and constructs.
> > > 
> ...
> > 
> > Somehow this simple driver is at v9 and still not landed. Do you have
> > someone from the drm maintainers/committers who's guiding you through all
> > this? I'm not seeing you Cc: a specific person, without that there's good
> > chances your contribution gets lost. I'm swamped myself, which is why I've
> > ignored this and hope you'd fine someone else and stick to them.
> 
> Hi Chenyang,
> 
> Please cc: me on the next revision - then I will take a look.
> But I count on someone more familiar with atomic modesetting can also
> take a look. Thomas? Maxime?

I think the main thing is deciding whether this should use simple display
pipe helpers or not. Right now it looks like, and it would greatly trim
down the code.

The only other things I check is whether there's any hooks that can be
removed and whether an attempt to send out the event is made in all cases,
and that's good enough for me on the atomic front :-)

If it's not using simple display pipe helpers there's a bunch more things
to check, like whether the plane check function looks competent or fails
to reinvent what simple pipe helpers have.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch