diff options
| author | Kenneth Graunke <[email protected]> | 2016-06-09 16:11:46 -0700 |
|---|---|---|
| committer | Kenneth Graunke <[email protected]> | 2016-06-12 00:39:45 -0700 |
| commit | a7d029d3dfac1da2701be75ff4d1589ac562e916 (patch) | |
| tree | 8db91ca6a74b049b1054a6799e23445ff4f26313 /src/mesa | |
| parent | 2213ffdb4bb79856f0556bdf2bfd4bdf57720232 (diff) | |
i965: Account for poor address calculations in Haswell CS scratch size.
Curro figured this out by investigating the simulator. Apparently
there's also a workaround in the Windows driver. I'm not sure it's
actually documented anywhere.
We were underallocating the scratch buffer by a factor of 128/70.
v2: Rename threads_per_subslice to scratch_ids_per_subslice
(suggested by Jordan Justen).
Cc: "12.0" <[email protected]>
Signed-off-by: Kenneth Graunke <[email protected]>
Reviewed-by: Francisco Jerez <[email protected]>
Reviewed-by: Jordan Justen <[email protected]>
Diffstat (limited to 'src/mesa')
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_cs.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_cs.c b/src/mesa/drivers/dri/i965/brw_cs.c index c8598d61891..22856b64179 100644 --- a/src/mesa/drivers/dri/i965/brw_cs.c +++ b/src/mesa/drivers/dri/i965/brw_cs.c @@ -150,9 +150,28 @@ brw_codegen_cs_prog(struct brw_context *brw, if (prog_data.base.total_scratch) { const unsigned subslices = MAX2(brw->intelScreen->subslice_total, 1); + + /* WaCSScratchSize:hsw + * + * Haswell's scratch space address calculation appears to be sparse + * rather than tightly packed. The Thread ID has bits indicating + * which subslice, EU within a subslice, and thread within an EU + * it is. There's a maximum of two slices and two subslices, so these + * can be stored with a single bit. Even though there are only 10 EUs + * per subslice, this is stored in 4 bits, so there's an effective + * maximum value of 16 EUs. Similarly, although there are only 7 + * threads per EU, this is stored in a 3 bit number, giving an effective + * maximum value of 8 threads per EU. + * + * This means that we need to use 16 * 8 instead of 10 * 7 for the + * number of threads per subslice. + */ + const unsigned scratch_ids_per_subslice = + brw->is_haswell ? 16 * 8 : brw->max_cs_threads; + brw_get_scratch_bo(brw, &brw->cs.base.scratch_bo, prog_data.base.total_scratch * - brw->max_cs_threads * subslices); + scratch_ids_per_subslice * subslices); } if (unlikely(INTEL_DEBUG & DEBUG_CS)) |