Re: [meta-fsl-arm][PATCH v4 0/9] iMX6Q BSP 1.1.0 upgrade

[Tomas Frydrych <tf+lists.yocto@r-finger.com>]

On 15/02/13 17:10, Thomas Senyk wrote:
>> Not that nice; in fact we shoudln't have the symlinks or X11 things
>> might end linking against framebuffer libraries by mistake.
> 
> This sounds rather unconventional ;)
> I've never seen any platform were libEGL-something.so is the EGL target to 
> link to.
> 
> In general one should define the default flavor of the GPU-driver
>    ... which is setting the libEGL.so symblink.
> 
> In relation to the "link by mistake"-argument:
> a) You have a fb-only setup: there will be no x11-things.
> b) You have a x11 setup: the default is libEGL-x11.so and theirfor no problem.
>     ... if on a x11 setup a application want to explicitly link against 
> libEGL-fb.so it can do anyway, but at least the default on is set.
> c) You have a dfb setup: the default link goes to libEGL-dfb.so
> 

Agreed; it generally makes little sense to have multiple versions of EGL
available at run time, and normal applications will be looking for
libEGL.so anyway.

> How do applications within the yocto build link against libEGL?
> There are generally no .pc file for GPU-drivers
>    ... are there internal variables to reference?

There is nothing Yocto specific here, how the application looks for EGL
is up to the application author. My recommendation would be if the
upstream driver does not provide a .pc file, to provide one as part of
the Yocto packaging, it is trivial to create one, and libraries such as
cogl will use it if they find it, and it saves much pain all around,
because other home grown ways of checking libEGL availability are
usually not cross-compilation friendly.

Tomas