[Mesa-dev] [RFC] r600g: evergreen/cayman tessellation support

[Alex Deucher]

On Mon, Nov 30, 2015 at 5:06 PM, Dave Airlie <airlied at gmail.com> wrote:
> On 30 November 2015 at 19:51, Marek Olšák <maraeo at gmail.com> wrote:
>> On Mon, Nov 30, 2015 at 7:20 AM, Dave Airlie <airlied at gmail.com> wrote:
>>> Hi,
>>>
>>> Patchbomb time, this set of patches is a first pass at add adding
>>> ARB_tessellation_shader support to the r600g driver. Only Evergreen
>>> and newer GPUs support tessellation. On any of the GPUs that support
>>> native FP64, this will enable OpenGL 4.1 on them.
>>>
>>> The first bunch of patches are a bit of a driver rework to get
>>> things in better shape for tessellation, they shouldn't cause
>>> any regressions.
>>>
>>> This runs heaven on cayman and should pass all the piglits
>>> unless I've done something wrong.
>>>
>>> Development hit two HW programming fun times, one with tess and
>>> dynamic GPR interaction requiring disabling dynamic GPRs, and
>>> one with programming of some SIMD registers to block TESS shaders
>>> on one unit. These fixed most of the hangs we saw during development.
>>>
>>> This doesn't contain SB support yet, Glenn has started working on it.
>>>
>>> Currently tested hw:
>>> working: CAYMAN, REDWOOD, BARTS, TURKS
>>> hangs on any tessellation: CAYMAN
>>> hangs differently at least with heaven: SUMO
>>
>> You listed CAYMAN twice, so does it hang or not?
>
> oops CAICOS I meant.
>
> I have some fglrx traces from it, I just haven't had time to dig into it yet.

The smaller parts have different numbers of gprs, etc. compared to the
bigger parts.  Might try tweaking the gpr allocations.

Alex