mirror of
https://github.com/RetroPortingToolKit/psxrecomp
synced 2026-10-26 02:11:36 -04:00
Matthew Stanley
0d15e2bd4e
Adds the cycle-paced sio_tick body, the sio_tick_quantum() wrapper, and
the pace_state TCP telemetry handler. Crucial change vs. failed 1.0c:
the dispatch-loop quantum tick is gated by g_sio_timing_active (volatile
int), so on the psx_check_interrupts hot path the cost is one load + one
branch when no SIO time is pending — not a full function call into the
cycle-paced loop.
In 1.0c-v2 the TX path is still synchronous and nothing arms shift_active
or pending_ack, so g_sio_timing_active stays 0. Phase 1.0d will set it
when arming the shifter and clear it when the shifter+buffer+ack are all
empty.
Files:
- sio.h: SIO_MODEL_CYCLE_PACED moved to header (default 1); declares
g_sio_timing_active (extern volatile int) and sio_tick_quantum()
- sio.c: defines g_sio_timing_active=0; adds cycle-paced helpers
(sio_consume_ack_event, sio_fire_ack_irq, sio_handle_shift_complete);
sio_tick gains a cycle-paced loop that runs only if shift_active or
pending_ack is set (currently never), then falls through to the legacy
IRQ countdown body which remains the live IRQ delivery path; adds
sio_get_pace_state(uint64_t out[16]) accessor
- interrupts.c: in psx_check_interrupts !in_exception block, calls
sio_tick_quantum only if g_sio_timing_active is set
- debug_server.c: new pace_state TCP handler exposing the snapshot
Validation against 64e0194 baseline:
- t=20s/30s TCP responsive; pad arm audit 2840/2840 no_ack=0
- 4x CROSS succeeds
- card txn distribution unchanged (10 txns reach bytes=15 ts=10)
- txn 0 still reads "MC" magic at bytes 10-11 (0x4D 0x43)
- pace_state: timing_active=0, all dynamic fields 0 throughout
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>