Commit Graph

3 Commits

Author SHA1 Message Date
e747742598 P7: Document TMEM column layout, add multi-row softmax test
docs/p7_tmem_column_layout.md: Verified that tcgen05.ld 32x32b.x8 is
the correct instruction for multi-row softmax. Each call reads 8 KV
positions for 32 rows. No instruction change needed from single-row.

test_p7_multi_row_softmax.py: Tests T=1,4,32,64,128 at various HD and N.
Gate: cos >= 0.999996.
2026-05-30 17:17:54 +00:00
6421f7c3f3 P4 RESOLVED: TMA hang was GMEM misalignment, not descriptor/driver issue
Evidence: TMA loads succeed with 128B-aligned GMEM on all descriptor configs.
The bit-21 workaround was NOT needed. The 'misaligned address' crashes were
caused by passing non-128B-aligned GMEM pointers to cp.async.bulk.tensor.

Added docs/p4_tma_hang_resolution.md with root cause and fix.
Cleaned up stale P4 test files.
2026-05-30 08:42:18 +00:00
a40c05f3f2 archive: TMA driver-API files + CUDA 13 TMA discovery notes
Key findings documented in docs/cuda13_tma_notes.md:
- CUDA 13 globalStrides are in BYTES not elements (root cause of desc creation failures)
- BFLOAT16 data type available in CUDA 13
- Driver API descriptors create OK but cp.async.bulk.tensor hangs on driver 13.0 + toolkit 13.2
- CuTeDSL tma_partition works (production path)

Archived (not deleted):
- fmha_tma_driver_api.cuh, fmha_6warp_tma_driver_api.cuh, test_fmha_tma_driver_api.cu
- These will work once driver matches toolkit version
2026-05-29 06:52:39 +00:00