It was a bit trickier to RE, since blob doesn't expose this
functionality at all, however we had a clue from the very beginning:
lima_blend_factor is 3 bits, i.e. 8 values, but only 5 of them were
used, it just waited till someone tried what 3 unused values do.
Interestingly enough, it turns out "5" works just as "0" (which is
PIPE_BLENDFACTOR_*SRC_*), but only if output register for gl_FragColor
is $0, So it looks suspiciously similar with PIPE_BLENDFACTOR_*SRC1_*
behavior, and looks like secondary output is taken from $0.
Since output regs for all other outputs are configured via RSW, there
must be a field in RSW for output register for secondary color, it's
likely 4 bits and it's currently set to 0 for reg $0.
Then it was just a matter of brute-forcing various consecutive 4 bits
in RSW - and indeed, setting top 4 bits of rsw->aux0 to the index of
gl_FragColor output register fixes blending tests when we use "5"
blend factor instead of "0".
So it must be a register number for gl_SecondaryFragColor. Unlike
gl_FragColor, the field is only repeated once in RSW.
Wire it up in compiler, and piglit arb_blend_func_extended now passes.
Reviewed-by: Andreas Baierl <ichgeh@imkreisrum.de>
Reviewed-by: Erico Nunes <nunes.erico@gmail.com>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13873>
Using 1 bit per wrap mode looked very suspicious and after some
experiments it turns out it's 3-bit enum.
Border color is also here, it sits right after depth field. For
some reason it uses 16 bit per channel just like for clear color in RSW
GL_CLAMP mode is broken for nearest filter just as on Midgard, so add
the same workaround - use GL_CLAMP_TO_EDGE for nearest filter.
Reviewed-by: Andreas Baierl <ichgeh@imkreisrum.de>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13213>
This makes the streams more readable and comparable with the blob's parser
as it parses the VS and PLBU stream and shows the currently known values.
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Signed-off-by: Andreas Baierl <ichgeh@imkreisrum.de>
