backend: Restore per-beat w_beat_done for compute retire - #166
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DanielKellerM wants to merge 1 commit into
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backend: Restore per-beat w_beat_done for compute retire#166DanielKellerM wants to merge 1 commit into
DanielKellerM wants to merge 1 commit into
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The compute engine retires its output beats on the write manager's ready. Since #163 that is w_dp_req_ready, which for an AXI burst pulses only on the last beat: correct for byte-count-preserving compute (transpose issues single-beat bursts) but it replays beat 0 across every beat of a multi-beat write burst. This partially reverts #163; the pulse becomes load-bearing for the multi-beat bursts size-changing compute produces. Re-expose w_beat_done = write_happening (strobe-independent, per-beat) from idma_axi_write and route it to the compute engine per active write protocol: AXI uses the per-beat pulse, other write ports keep w_dp_ready (already per-beat, e.g. OBI). No behavior change for single-beat transpose bursts.
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Summary
The compute engine retires its output beats on the write manager's ready. Since #163 that is
w_dp_req_ready, which for an AXI burst pulses only on the last beat: correct for byte-count-preserving compute (transpose issues single-beat bursts), but it replays beat 0 across every beat of a multi-beat write burst.This partially reverts #163:
w_beat_done = write_happening(strobe-independent, per-beat) is re-exposed fromidma_axi_writeand routed to the compute engine per active write protocol. AXI uses the per-beat pulse; other write ports keepw_dp_ready, which is already per-beat (e.g. OBI). The pulse becomes load-bearing for the multi-beat bursts that size-changing compute (follow-up PR) produces.No behavior change for single-beat transpose bursts.
Validation
devel;tb_idma_transpose_b2bgreen at DataWidth 32/64 (Questa 2026.1) at this commit alone.r_axil_w_axi,r_axis_w_axi,rw_tilelink, and multihead variants: exactly onew_beat_donedeclaration and drive per topology.