hw: fix WMMA fp16/bf16 RTL output handling#359
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Issue
WMMA fp16->fp16 and bf16->bf16 did not follow
fmt_d. The RTL always treated the accumulator input/output path as FP32.Root Cause
VX_tcu_fedp_bhfwas missing destination-format handling. Whenfmt_dselected fp16 or bf16, the RTL still produced FP32-formatted bits instead of the expected 16-bit fp16/bf16 result in the low halfword.Proposal
Add
fmt_dhandling in the BHF TCU datapath so fp16 and bf16 WMMA outputs are rounded and packed in the expected destination format. Extend the SGEMM TCU regression coverage to include fp16->fp16 and bf16->bf16 cases, with ULP checks in the native 16-bit encoding space.This fix passes the synthesis testing.