[Nouveau] Dealing with opencl kernel parameters in nouveau now that RES support is gone

[Hans de Goede]

Hi,

On 22-02-16 14:04, Samuel Pitoiset wrote:
>
> On 02/22/2016 01:46 PM, Hans de Goede wrote:
>> Hi,
>>
>> On 22-02-16 13:41, Samuel Pitoiset wrote:
>>> Hi there,
>>>
>>> On 02/22/2016 12:26 PM, Hans de Goede wrote:
>>
>> <snip>
>>
>>>> So back to the problem of getting OpenCL(ish) code to work again with
>>>> the recent mesa changes. For starters I would like to get:
>>>>
>>>> src/gallium/tests/trivial/compute.c and then the test with mask 8,
>>>> test_input_global() to work again, when that is working I should be
>>>> able to adjust my llvm work (and if necessary clover) to start to
>>>> work again.
>>>>
>>>> Currently the test_input_global() test uses the following bit of
>>>> TGSI code:
>>>>
>>>> COMP
>>>> DCL SV[0], THREAD_ID[0]
>>>> DCL TEMP[0], LOCAL
>>>> DCL TEMP[1], LOCAL
>>>> IMM UINT32 { 8, 0, 0, 0 }
>>>>
>>>>     BGNSUB\n"
>>>>         UMUL TEMP[0], SV[0], IMM[0]
>>>>         LOAD TEMP[1].xy, RINPUT, TEMP[0]
>>>>         LOAD TEMP[0].x, RGLOBAL, TEMP[1].yyyy
>>>>         UADD TEMP[1].x, TEMP[0], -TEMP[1]
>>>>         STORE RGLOBAL.x, TEMP[1].yyyy, TEMP[1]
>>>>         RET
>>>>     ENDSUB
>>>>
>>>>
>>>> Where by RINPUT and RGLOBAL get replaces by processing the
>>>> code with cpp and the following defines:
>>>>
>>>> #define RGLOBAL        RES[32767]
>>>> #define RLOCAL         RES[32766]
>>>> #define RPRIVATE       RES[32765]
>>>> #define RINPUT         RES[32764]
>>>>
>>>> If I understand how memory is supposed to work, then I would need to
>>>> change the TGSI as follows:
>>>>
>>>> COMP
>>>> DCL SV[0], THREAD_ID[0]
>>>> DCL MEMORY[0]
>>>> DCL TEMP[0], LOCAL
>>>> DCL TEMP[1], LOCAL
>>>> IMM UINT32 { 8, 0, 0, 0 }
>>>>
>>>> BGNSUB\n"
>>>> UMUL TEMP[0], SV[0], IMM[0]
>>>> LOAD TEMP[1].xy, RINPUT, TEMP[0]
>>>> LOAD TEMP[0].x, MEMORY[0], TEMP[1].yyyy
>>>> UADD TEMP[1].x, TEMP[0], -TEMP[1]
>>>> STORE MEMORY[0].x, TEMP[1].yyyy, TEMP[1]
>>>> RET
>>>> ENDSUB
>>>
>>> Nope, this won't work because RINPUT is RES[32764]. And you have to
>>> remove all occurrences to RES because it's not longer supported. In my
>>> opinion, using BUFFER[0] in a first time should work. Currently, only
>>> SHARED with MEMORY is supported.
>>
>> Right, as I say below "This only solves the accessing of the global
>> memory, it does not solve
>> getting to the kernel input kernel parameters"
>>
>>>> This assumes, that as discussed declaring memory without a , SHARED or
>>>> other
>>>> flag means the memory is global.
>>>>
>>>> So 2 questions:
>>>>
>>>> 1) Do the above changes for using the new MEMORY keyword look as
>>>> intended
>>>> to you?
>>>>
>>>> 2) This only solves the accessing of the global memory, it does not
>>>> solve
>>>> getting to the kernel input kernel parameters, how would I deal with
>>>> those ?
>>>
>>> The input kernel parameters are directly passed through a call to
>>> pipe_context::launch_grid. You just have to fill the
>>> pipe_grid_info::input array with your parameters and they will be
>>> uploaded by nvXX_compute_upload_input().
>>
>> Right, the uploading side I understand, the question is how to get to
>> them from
>> the compute kernel's tgsi code ?
>
> Right, I wonder if there is already a DECL INPUT or something like that for input parameters of shaders. Oh yeah, there is TGSI_FILE_INPUT, maybe this is what you want?

Yes that sounds right, so now "all" we need to do is make
nvXX_compute_upload_input() and TGSI_FILE_INPUT work together.

Regards,

Hans