[Openpvrsgx-devgroup] Intel Poulsbo

[H. Nikolaus Schaller]

Hi Jeffrey,

> Am 22.04.2020 um 20:32 schrieb Jeffrey Mckenzie <jeffreymckenzie094 at gmail.com>:
> 
> Hello,
> 
> I have a Sony Vaio P based on a Intel Poulsbo with a GMA500, that is
> based on a PowerVR SGX 535.

Oh great!

> What work would be needed to get this to work? Is this x86 SoC
> compatible with the DTS bindings that are currently being developed?

Well, I don't know which bindings it needs but I expect it not to be
much different.

We have a TI DDK 1.14 version which contains some pvrsrvkm components
specific to the Poulsbo. So studying this code may help to identify
what differs.

http://git.goldelico.com/?p=letux-kernel.git;a=tree;f=drivers/gpu/drm/pvrsgx/1.14.3699939/eurasia_km/services4/system/poulsbo;h=c286c9a42ff2a4ce61c8e3219726959968a0771c;hb=refs/heads/letux/pvrsrvkm-1.14.3699939

Unfortunately this variant is no longer available for the latest DDK
we are trying to use which is the DDK 1.17.

But there the SoC specific differences are much smaller so that
it should not be too difficult to either forward-port the 1.14
code for Poulsbo to it or end up in a more generic one.

So this might at least provide the kernel driver pvrsrvkm.ko

> Are there any userspace blobs that are suitable for Linux on x86?

Unfortunately I am not aware of any. What I have started to try
is to run the arm version of pvrsrvctl (which downloads the firmware)
in quemu-arm-static on the MIPS based jz4780. But I have not yet
installed all arm libraries it expects. But this seems to be
a potential way to get it running.

Another issue may be that the firmware is SGX revision specific.
There is one for sgx530, one for sgx540 and for sgx544 but we don't
have one for sgx535.

So what is the original system running on your Vaio P? Is there any
(old) Linux with (old) GPU support? Another choice could be if we
find some device with sgx535 and Android. This should also provide
some binary blobs for experimentation.

But I know that it is still a long way to open source replacements...

BR,
Nikolaus