 Jason
|
fcf3999e39
|
Fix CDC reset domain bug (P0), strengthen testbenches with 31 structural assertions
Split cdc_adc_to_processing reset_n into src_reset_n/dst_reset_n so source
and destination clock domains use correctly-synchronized resets. Previously
cdc_chirp_counter's destination-side sync chain (100MHz) was reset by
sys_reset_120m_n (120MHz domain), causing 30 CDC critical warnings.
RTL changes:
- cdc_modules.v: split reset port, source logic uses src_reset_n,
destination sync chains + output logic use dst_reset_n
- radar_system_top.v: cdc_chirp_counter gets proper per-domain resets
- ddc_400m.v: CDC_FIR_i/q use reset_n_400m (src) and reset_n (dst)
- formal/fv_cdc_adc.v: updated wrapper for new port interface
Build 7 fixes (previously untouched):
- radar_transmitter.v: SPI level-shifter assigns, STM32 GPIO CDC sync
- latency_buffer_2159.v: BRAM read registration
- constraints: ft601 IOB -quiet fix
- tb_latency_buffer.v: updated for BRAM changes
Testbench hardening (tb_cdc_modules.v, +31 new assertions):
- A5-A7: split-domain reset tests (staggered deassertion, independent
dst reset while src active — catches the P0 bug class)
- A8: port connectivity (no X/Z on outputs)
- B7: cdc_single_bit port connectivity
- C6: cdc_handshake reset recovery + port connectivity
Full regression: 13/13 test suites pass (257 total assertions).
|
2026-03-17 19:38:09 +02:00 |
|
|
Jason
|
fb59e98737
|
Add SymbiYosys formal verification for 6 modules, fix 2 doppler bugs
Formal verification (SymbiYosys + smtbmc/z3):
- cdc_single_bit: BMC PASS depth 80, cover PASS 3/3
- cdc_handshake: BMC PASS depth 100, cover PASS 4/4
- cdc_adc_to_processing: BMC PASS depth 80, cover PASS
- radar_mode_controller: BMC PASS depth 200, cover PASS 8/8
- range_bin_decimator: cover PASS 7/7, BMC running (step 61+)
- doppler_processor: cover running (step 133/150), BMC running (step 35+)
DUT bug fixes found by formal:
- doppler_processor: write_chirp_index overflow past CHIRPS_PER_FRAME-1
in S_ACCUMULATE frame-complete branch (reset to 0)
- doppler_processor: read_doppler_index unclamped prefetch in S_LOAD_FFT
causing OOB BRAM reads (clamped to DOPPLER_FFT_SIZE-1)
CDC fix (prior session, included):
- cdc_modules: async reset changed to sync reset on all CDC sync chains
to prevent metastability on reset deassertion
RTL changes for formal observability:
- Added ifdef FORMAL output ports to cdc_handshake (6), cdc_adc (2),
radar_mode_controller (2), range_bin_decimator (5), doppler_processor (11)
|
2026-03-17 12:47:22 +02:00 |
|