[Openpvrsgx-devgroup] Intel Poulsbo

[H. Nikolaus Schaller]

Hi Jeffrey,

> Am 23.04.2020 um 17:47 schrieb Jeffrey Mckenzie <jeffreymckenzie094 at gmail.com>:
> 
>> See here for the pci id table used by the gma500 driver for autodetection:
>> https://github.com/torvalds/linux/blob/v5.6/drivers/gpu/drm/gma500/psb_drv.c#L40-L99
> 
> I see.
> 
>> I've had work done already to add page_flip support to the gma500
>> driver for psb and cdv variants in the mainline kernel so that this
>> hardware can be used with a wayland based graphics stack for an
>> embedded cdv/gma3650 platform I'm supporting, psb/gma500 was
>> also supported at the same time.
> 
> Awesome!
> 
>> While my use case luckily doesn't
>> have a hard requirement on acceleration it would be handy to have
>> so I'd be willing to support any project working on a fully open source
>> accelerated driver as I have a very large amount of these boards I
>> will need to support indefinitely on a mainline kernel. From my
>> understanding the accelerated drivers Intel released for older kernels
>> do not support 64 bit however so using those would not be feasible
>> as I use a 64 bit mainline kernel. The changes to support wayland
>> were only recently added in the mainline kernel 5.6 release.
> 
> I would also support this, but I think that's simply too much work and
> I'm definitely not skilled enough for this. I've read this blog from
> libv and I'm not really optimistic about it, to be honest:
> https://libv.livejournal.com/26972.html
> 
> It seems that this project is about shaping the out-of-tree kernel
> drivers and use it with the existing userspace blobs, which would be
> good enough for me. I would like to have working 3D on an otherwise
> more modern software stack. This seems to be a successful way of
> achieving it, considering what the Maemo Leste people have done for
> the Motorola Droid 4.
> 
> But I'm clueless about the differences between the kernel modules. If
> we would use the proprietary userspace blobs for 3D OpenGL
> acceleration, which driver should be used? The GMA500 is already
> mainlined, but support seems to be limited to kernel modesetting, 2D
> acceleration and thanks to you also supports page_flip. The other
> works for OMAP with the blobs, but would it make sense to use it on
> x86, considering it does not make any use of DTs?
> 
> @Nikolaus: what kind of file is the firmware? Have you searched
> through the EMGD-Community/intel-binaries-linux repository before for
> the firmware file of the SGX535?

The firmware (at least for ARM & MIPS) seems to be a blob compiled
into the user-space lib called libsrv_um.so [1]. The pvrsrvctl
binary seems to know how to inject it into the SGX hardware.

So it is not a separate firmware file.

No I didn't know about the EMGD community. But it is interesting.
There is some pvr driver [2]. It seems to be yet another DDK version
1.5.15.3226 [3].

BR,
Nikolaus

[1]: https://git.ti.com/cgit/graphics/omap5-sgx-ddk-um-linux/tree/targetfs/ti654x/lib?h=ti-img-sgx/zeus/1.17.4948957
[2]: https://github.com/EMGD-Community/intel-binaries-linux/tree/master/drm
[3]: https://github.com/EMGD-Community/intel-binaries-linux/blob/master/drm/pvr/include4/pvrversion.h