Re: [OE-core] [PATCH] mesa.inc: add dispmanx support

["Trevor Woerner" <twoerner@gmail.com>]

On Fri 2020-12-04 @ 11:51:41 AM, Phil Blundell wrote:
> On Thu, Dec 03, 2020 at 05:35:23PM -0500, Trevor Woerner wrote:
> > On Thu, Dec 3, 2020 at 5:25 PM Phil Blundell <pb@pbcl.net> wrote:
> > 
> > > If we're talking about OpenGLES applications, wouldn't you already have
> > > opengl in DISTRO_FEATURES?
> > >
> > 
> > Not necessarily.
> > 
> > Adding opengl to DISTRO_FEATURES really means "enable a bunch of
> > PACKAGECONFIGs all over the place because I need x11 and mesa with all the
> > bells and whistles".
> 
> It sounds like there are a few things that have gone wrong here then.
> Firstly, "opengl" in DISTRO_FEATURES isn't supposed to imply anything
> about x11.  If it does, that's just a bug. 

I have this bad habit of saying something specific when I actually mean to use
something as an example, sorry. I meant to say "if, for example, i'm building
an image for x11, and want opengl support…". As far as I can tell enabling
opengl in DISTRO_FEATURES doesn't imply x11 in any way, sorry :-)

> It should indeed enable opengl
> support in other recipes, though.  Can you give an example of the sort
> of thing that's getting enabled there that you don't want?

I am seeing an issue, but after quite a bit of testing and checking, I now
realize that the issue I was seeing is because of something a BSP layer is
doing and is not related to anything in core.

> But secondly, thinking about it again, there's no reason for mesa itself
> to require opengl in DISTRO_FEATURES anyway.  Mesa itself is what provides
> the GL API so it clearly doesn't depend on it.  I think that existing
> DISTRO_FEATURE check in mesa is just bogus and should be removed entirely.

Excellent, I agree.

If I understand it correctly, mesa can PROVIDE more than just the GL
interface; it can, for example, PROVIDE gbm which is useful for situations
where GL is provided via a binary (such as in my case with Raspberry Pi's
userland).

I'll send a patch.

Best regards,
	Trevor