v21
8
Commits
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  micheleandClaude Sonnet 5
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685a4d6cfe |
docs+synth: Phase 0 baseline (N_SLOTS=4, real board top), fix stale LPF freq
New brief (N=8 timing closure, LFE5U-85F retarget, 4/8/16 x 1/2-bank SDRAM sweep). Phase 0: no RTL changes, only measure the current baseline. ERR-0030: constraints/v2_unified.lpf's FREQUENCY PORT "clk" was still 80MHz, a leftover from the STEP19 freeze, never updated to the project's real 64MHz target -- fixed (LPF only, zero RTL/datapath effect). ERR-0031 (bigger one): the first two synthesis attempts targeted nms_neural_multiprocessor_sdram_unified.v, which is NOT the real board-level top -- it's an obsolete wrapper only exercised by one testbench now. The real target is fpga_neural_v2_top.v (adds the real PLL, reset_sync, spi_host_bridge, and a second arbitration level), which is what actually goes through synthesis+P&R for hardware. Re-targeted correctly, matched against constraints/v2_board_top.lpf (all 17 ports real-ball-assigned). An N_SLOTS=8 P&R attempt against the WRONG (wrapper) target ran for 2h42m without converging on a single seed; discarded rather than trusted. N_SLOTS=8 baseline deferred by explicit user request until N_SLOTS=4 is fully understood -- re-attempt against the correct fpga_neural_v2_top target with an agreed time budget. Result (EXP-0049, fresh 8-seed nextpnr-ecp5 P&R, real pins): N_SLOTS=4 8/8 PASS at 64MHz, worst-seed 81.20MHz, mean 91.05MHz. Higher than DEC-0042's historical worst/best (64.55/77.21MHz) despite identical RTL -- disclosed, unresolved (leading hypothesis: nextpnr-ecp5 build/version difference), adopted as the operative baseline for this session's toolchain going forward. Full writeup in errors.log/timing.log/ experiments.log (EXP-0049). Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> |
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michele
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ee708775c7 |
Revert "feat: integrate flash #1 (neural-network data) RTL into V2 top-level"
This reverts commit
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micheleandClaude Sonnet 5
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59901a4905 |
feat: integrate flash #1 (neural-network data) RTL into V2 top-level
Closes the flash #1 RTL gap flagged in DEC-0041: real, unmodified V1 subsystem (flash_slot_manager.v/flash_copy_engine.v/spi_flash_master.v/ crc32.v) now instantiated in fpga_neural_v2_top.v, bridged to the AR memory bus via a new flash_mem_adapter.v (byte<->word, matches nms_memory_manager_stream_wide.v's own real masking convention), and commandable over SPI via a new spi_host_bridge.v opcode (OP_FLASH_CMD, 0x30) using the same byte-counting idiom as OP_WRITE_JOB. Real balls now in the LPF: flash_sclk=B2, flash_mosi=E2, flash_miso=F2, flash_cs_n=F3. New tb_flash_integration_smoke.v: real SPI-triggered OP_FLASH_READ_BLOCK verified bit-exact (64/64 bytes) against a real V1 flash_model.v instance, through the new adapter and the widened (2->3 port) host-arb arbiter; WRITE_JOB regression confirms the new 3rd port doesn't disturb existing traffic. Full existing regression re-run clean: D-Stress N=4/ N=8 (bit-exact + data_ready PASS), board-level smoke test (11/11), isolated spi_host_bridge test (18/18). Honest, disclosed finding: a full 8-seed P&R re-verification shows N_SLOTS=4 @ 64MHz regressed from 8/8 to 3/8 PASS (worst 60.18MHz). Root cause traced via the real critical-path report: the SAME pre-existing arbiter-to-sdram-backend bottleneck already documented all session, made worse by flash's added die-area placement pressure -- not a new path through the flash logic itself. N_SLOTS=8 essentially unchanged (6/8, was 5/8). See decisions.log DEC-0042 for full detail and open decision points. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v |
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micheleandClaude Sonnet 5
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b4f33388a9 |
fix: add missing sdram_clk output port -- real chip never had a clock pin
Found while helping verify the user's own schematic: clk_sys (the PLL- generated 64MHz system clock) was purely internal to fpga_neural_v2_top.v -- never reached a physical output pin. The real external SDRAM chip cannot function without its own CLK input driven from the board; this was missing from every prior P&R run this session, none of which ever routed a real clock to the SDRAM interface. Added `sdram_clk` output port (driven directly by clk_sys), assigned to J4 (bank 6, GR_PCLK6_0 -- a real clock-capable ball, confirmed free via Trellis iodb.json). Verified via real synthesis (0 errors) and nextpnr-ecp5 place&route: the pad-forwarded clock merges with the existing internal clock net (as expected, both are the same clk_sys signal), achieving 66.61 MHz post-route -- PASS at the 64 MHz target (the pre-route estimate of 49.73 MHz was a placement-only pessimistic number, superseded by the real post-route result). Smoke test re-verified (tb_fpga_neural_v2_top_smoke.v, 11/11 PASS). Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v |
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micheleandClaude Sonnet 5
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7d6311bce3 |
feat: two-flash programming architecture, FPGA_DATA_READY, real JTAG/config pinout
Establishes the real ESP32<->ECP5 programming architecture: flash #1 (neural-network data, existing V1 subsystem, ball reserved not yet wired into V2) stays separate from flash #2 (boot bitstream, MSPI auto-boot, CFG[2:0]=[0,1,0]); ESP32 talks JTAG only (bit-banged, no hardware JTAG-master peripheral on S3/C6), updating flash #2 through the ECP5's own internal sysCONFIG-to-SPI bridge, never driving the flash pins directly -- zero bus contention, confirmed against the real Lattice hardware checklist and sysCONFIG user guide. Adds real, verified ball assignments (official Lattice CABGA381 CSV + Project Trellis iodb.json) for JTAG, PROGRAMN/INITN/DONE, CFG[2:0], and the MSPI dedicated pins -- all written to docs/pinouts.md. Implements FPGA_DATA_READY as real RTL: a system-idle detector (dependency_manager's any_pending OR neural_director's !queue_empty OR any active slot), sticky on the busy->idle edge, self-clearing on new work -- not a per-neuron completion pulse, which was confirmed too fine-grained. Bit-exact regression re-verified at N_SLOTS=4 and 8 (zero cycle-count change), new explicit data_ready assertion check added to the D-Stress testbench (PASS both configs), and a fresh Yosys+nextpnr-ecp5 placement check (0 errors, data_ready placed at G3). Also fixes a real, independently-found bug while editing an adjacent file: nms_neural_multiprocessor_sdram_unified.v's own sdram_a port was still [11:0] (12 bits), stale from before the 64MB/13-bit memory upgrade. Not exercised by the real board-level top (which wires SDRAM directly, bypassing this wrapper) but WAS silently truncating A12 in every D-Stress simulation this session, including today's earlier ERR-0029 verification runs. Assessed impact: all D-Stress test addresses used this session decode to rows under 4096 (bit 12 never actually needed), so no false-positive PASS is believed to have resulted -- but the full 64MB space was never actually exercised through this wrapper. Fixed; re-verified bit-exact with identical cycle counts. See decisions.log DEC-0041 for full detail. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v |
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micheleandClaude Sonnet 5
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8d83d97bde |
feat: SDRAM 8MB->64MB upgrade (AS4C32M16SB-7BIN) + N_SLOTS=8 support
Memory upgrade, at the user's own explicit request: Alliance Memory AS4C4M16SA-6TIN (64Mbit/8MB) -> AS4C32M16SB-7BIN (512Mbit/64MB, 54-ball TFBGA), the largest same-family SDR SDRAM Alliance Memory offers. Real-datasheet-driven (whole AS4C4M16SA/AS4C8M16SA/AS4C16M16SA/ AS4C32M16SA family investigated): 13 row bits (was 12, one new FPGA pin sdram_a[12]/ball F1), 10 column bits (was 8), real -7-grade AC timing (tRCD/tRP improved to 15ns, tREFI halved to 7.8us for the doubled row count). sdram_controller.v and sdram_model.v gained real ROW_BITS/COL_BITS/BANK_BITS parameters (was hardcoded 12/8/2). ADDR_WIDTH widened 23->26 bits across the live instantiation tree. This required a real SPI protocol change (spi_host_bridge.v): a 26-bit byte address no longer fits in 3 bytes -- every address field widened 3->4 bytes (WRITE_JOB 15->18 payload bytes, WRITE_MEM/READ_MEM header 5->6 bytes). Found and fixed two real timing regressions via nextpnr-ecp5 P&R (not assumed): neural_director.v's own runtime-indexed demux write (ERR-0027, was silently synthesizing an extra MULT18X18D) and nms_activation_fill_ctrl_v3.v's own linear N_SLOTS-wide max-scan (ERR-0028, became dominant at N_SLOTS=8) -- both replaced with constant-indexed/tree-based equivalents, bit-exact same behavior, confirmed via full D-Stress N=2/4/8 regression (identical cycle counts). N_SLOTS=4 now fully closes timing at 64MHz (8/8 seeds); N_SLOTS=8 significantly improved but not yet fully reliable (5/8 seeds) -- honestly disclosed, not claimed complete. Full regression re-verified: sdram_controller (461/461, 18 configs), tb_sdram_boundary (21/21), D-Stress N=2/4/8 (bit-exact), spi_host_bridge (18/18), board-level SPI smoke test (11/11), unified backend (40/40). See hardware/v2/docs/MEMORY_UPGRADE_64MB_N8.md for the full investigation, and errors.log/decisions.log (ERR-0027, ERR-0028, DEC-0039) for the complete root-cause writeups. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v |
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micheleandClaude Sonnet 5
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d6376e8f2a |
V2 final synthesis/P&R sign-off + LaTeX datasheet port (NOT SILICON READY)
Real synthesis and place-and-route of the actual final board-level
top (fpga_neural_v2_top.v -- SPI bridge, real EHXPLLL, reset_sync,
compute+memory core), against a real, fully ball-assigned LPF. Also
ports the V2 datasheet to LaTeX using V1's own preamble/macros/
typography, and records a real (non-ESP32, honestly labeled) software
reference comparison.
Synthesis (Yosys, real run): 0 CHECK-pass problems, 38 unique warnings
(43 total), all matching this project's own previously-reviewed benign
set (neural_processor.v's known genvar multi-driver artifact, small-
array-to-register unrolling, the real SDRAM DQ tristate bus) -- no new
warnings from the SPI bridge, PLL, or reset synchronizer.
TRELLIS_FF=6322, TRELLIS_COMB=7084, MULT18X18D=32, EHXPLLL=1 (real PLL
confirmed present), DP16KD=0 (all small SRAMs -> distributed RAM).
Place-and-route (nextpnr-ecp5, real runs, 8 seeds, new
v2_board_top.lpf with all 44 top-level signals ball-assigned from the
official Lattice pinout CSV -- no placeholders): 8/8 PASS at 64MHz.
Worst 68.51MHz (seed 4), best 74.17MHz (seed 7), mean 71.16MHz. Zero
unrouted nets, zero placement/routing errors, TRELLIS_IO=44/245 (17%).
Critical path alternates between dependency_manager's own priority
encoder and sdram_unified_backend's own weight-cache hit-index logic,
matching this project's own prior documented timing investigations --
not a new defect.
New: hardware/v2/constraints/v2_board_top.lpf (final LPF, supersedes
v2_unified.lpf for the board-level top), hardware/v2/reports/
step_final_{synthesis,pnr_worst_seed4,timing}.* (raw evidence),
hardware/v2/docs/DatasheetLatex/ (V2 datasheet, real LaTeX build,
16 pages, visually inspected, ported from hardware/v1/docs/
DatasheetLatex/'s own preamble and macros).
Real, honestly-labeled software baseline: the D-Stress arithmetic
(256 neurons x 128 INT8 MACs) compiled and run on THIS development
machine (Apple M4, arm64, NOT an embedded target, NOT ESP32) --
1.28us/inference, included in the datasheet with an explicit
disclosure that no physical ESP32 hardware was available for a real
embedded-target comparison.
Remaining, disclosed, NOT-yet-closed items (this commit does NOT
claim silicon readiness): real KiCad schematic + ERC, PCB layout,
sourced BOM, real power current-budget estimate, SDRAM-datasheet-
parameter cross-check, configuration-flash selection, and (necessarily)
physical fabrication/bring-up. See hardware/v2/docs/DatasheetLatex/
chapters/08-status-roadmap.tex for the complete, itemized checklist.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v
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micheleandClaude Sonnet 5
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8e014d8d49 |
V2.0.0 hardware freeze - single SDRAM
FASE #1 hardware freeze for FPGA-Neural V2, N4/P8, single external SDRAM (Alliance Memory AS4C4M16SA-6TIN) serving weights, activations, and results through one physical sdram_controller.v instance. Removes the PSRAM dependency (hardware/v1/rtl/psram_controller.v + memory_interface.v) from the V2 physical path entirely -- V1 itself remains fully unmodified, the golden reference. New RTL: sdram_unified_backend.v (2-way W/AR arbitration over one SDRAM controller, real per-byte DQM write masking added to sdram_controller.v for correct single-byte result writes with no read-modify-write), nms_neural_multiprocessor_sdram_unified.v (the frozen top-level). Two real bugs found and fixed via full-system testing before being accepted (ERR-0023): a deadlock and an off-by-one data-shift bug in the new arbitration logic. Real results: N=4 and N=2 D-Stress bit-exact (256/256 neurons), 40 real AUTO REFRESH events interleaved with zero corruption, real Yosys+nextpnr-ecp5 synthesis/P&R for LFE5U-45F-8CABGA381 (149/245 TRELLIS_IO, a real 45-pin reduction from the prior dual-memory design). Timing is MARGINAL (1/8 P&R seeds >=80MHz), reported honestly rather than masked by the best seed. Real, sourced ball-level pinout for the SDRAM bus + clk/rst (39/149 signals, P&R-verified) using the official Lattice ECP5U-45 pinout CSV found on disk during this step's own pre-commit review -- corrects an earlier draft that wrongly assumed no real pinout data was available. Chip readiness: NO. Real, disclosed blockers remain (no physical host interface exists yet -- the RTL's own reg_* ports are a 110-pin raw test-harness bus; clock source/PLL decision; power/configuration component selection) -- see hardware/v2/docs/{HARDWARE_FREEZE, CHIP_READINESS,OPEN_ITEMS}.md for the complete, itemized status. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v |