On 31.08.2017 21:53, Daniel Abrecht wrote:

> While all android phones technically use a linux kernel, they have > nothing else in common with a normal Linux system. Android has it's>
own libc: bionic.

One of my goals in the gnudroid project (which is currently stalled
due lack of time) is porting it to glibc or uclibc.

> It also has special IPC mechanisms enabled in the > linux kernel,

Binder already is mainlined. Not sure whether it's properly namespace'd
yet, but that shouldn't be the big deal.

> and it uses gralloc instead of fbdev or DRM.

IIRC, gralloc is used to allocate intermediate surface buffers,
for both GPUs and other image/video processing devices, and allows
passing them between processes (similar to gem or prime). Not checked,
but they probably have something that finally bridges to GEMs, so GPUs
drivers can consume the buffers (if not, shouldn't be such a hard job
to add that). I'd guess sooner or later will come up with something
similar, as a complete video processing pipe (involving dri and v4l
devices) is an ongoing topic for quite some time.

> I Really hope the Librem 5 will get fbdev support, so I can see boot > messages on a framebuffer console, and optionally DRM support for>
things like OpenGL and Vulkan.
plain fbdev shouldn't be the big deal as soon as basic KMS stuff
is implemented. in embedded world it's usally just a matter of
properly enabling the ipu (for most SOCs should be mainlined) and
backlight (usually some dumb pwm controller, either in the SoC or
behind I2C).

When bringing up an own custom board, that's one of the early steps
(and beyond the SOC-stuff usually board specific).


--mtx