Partial work toward FABRIC.md punch list item 2.2. Adds the
STADIUM_MAX_VM_COUNT Kconfig symbol (default 4, per item 1.5) wired
through Makefile.starkernel, a new CAPSULE_RUN_ERR_FLEET_FULL result
code, and a vm_registry_live_count() helper in capsule_birth.c that
counts LIVE VMs only (distinct from the existing monotonic
vm_registry_count, which never decrements on death).
NOT YET DONE: nothing calls vm_registry_live_count() yet -- the actual
birth-refusal check is not wired into capsule_birth_baby(). Not built,
not boot-tested. FABRIC.md's item 2.2 checkbox is deliberately left
unchecked; this commit exists only to save in-progress work before a
pause, not to claim the item complete.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 2.1 complete.
vm_physics_touch() no longer takes a wall-clock timestamp -- it reads
fleet_heartbeat_tick_count internally, which is execution-paced
(vm_runtime.c:143), not wall-clock. VMPhysics.last_active_ns ->
last_active_tick, VMFleetTouchSample.elapsed_us -> elapsed_ticks, and a
new explicit `touched` flag replaces the old `> 0` sentinel (tick 0 is
a legitimate value a first touch can land on, unlike wall-clock ns).
Verified: three-architecture boot (amd64 x2, aarch64, riscv64), all
reaching ok> with identical dict_hash=0x3d4e1daf289da94f matching the
item-0.10 baseline. No new compiler warnings in the touched files.
Honestly flagged, not fixed: with Tripod pruned to Hera alone (item
0.1), vm_physics_touch()'s fan-out has no other live VM to pull heat
from, so the fleet-heat-sum acceptance criterion is trivially satisfied
rather than genuinely stress-tested -- a real check needs Phase 4's
multi-VM fleet. fleet_transfer_slope_q48's seed (65536/3) was
calibrated for elapsed microseconds and has not been re-fit for elapsed
ticks; left as-is rather than guessed, deferred to item 5.1's DoE work.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Introduces src/starkernel/heartbeat.c as the shared top/bottom-half
implementation of heartbeat_init/tick/service/ticks/trust/state, replacing
the per-architecture duplicates in amd64/riscv64/aarch64 timer.c. Each
arch's timer.c now contributes only heartbeat_read_counter() (rdtsc /
rdtime / CNTPCT_EL0). Per the GAP-A1 ruling the top half stays counter+
latch only; heartbeat_service() (called every REPL idle iteration,
unconditionally per FABRIC.md's fidelity note) does the window/variance/
trust work outside interrupt context. vm_tick()'s call sites are
unchanged -- the engine still runs on the virtual tick.
Per FABRIC.md §26 (ruled 2026-08-03): wires Loop #7's execution-derived
stable/volatile signal into the physical re-arm period. vm_runtime.c's
existing Loop #7 site now calls heartbeat_set_adaptive_period_ns() with
tick_target_ns ratio-rescaled onto a 10ms kernel base (not the hosted
10us HEARTBEAT_TICK_NS -- see §26.3 for the scale mismatch). Each
architecture's re-arm function (apic_timer_rearm() on amd64/aarch64,
riscv64_timer_rearm()) now converts heartbeat_next_period_ns() to its
own raw counter units instead of a fixed constant; amd64 gained a
rearm function it didn't previously need, since periodic-mode auto-reload
never required one before this item.
Verified: all three architectures build with no new warnings and boot
cleanly to ok> with dict_hash=0x3d4e1daf289da94f, unchanged from the
pre-change baseline -- no regression. Verified NOT achieved: live re-arm
period variation under load. A temporary diagnostic (added and reverted)
confirmed Loop #7 never actually fired during a live QEMU session -- a
synthetic word-execution loop drove ~6,500 executions, past the 1000-tick
inference frequency, without tripping vm_tick_inference_engine()'s
pre-existing !vm->rolling_window.is_warm gate. That gate predates this
item and was not investigated -- out of scope. FABRIC.md's Done-when is
amended to record this honestly rather than claim it.
Punch list §25 item 0.8 complete (per amended, weaker acceptance -- see
the item's own annotation).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 0.3 NOT complete.
- Added `starkernel/fdt.h` and `fdt.c` for minimal read-only devicetree parsing: sufficient for boot-time lookups such as `timebase-frequency`.
- Bootloader now captures the devicetree blob (DTB) from `EFI_DTB_TABLE_GUID` into `BootInfo::dtb`.
- RISC-V timer subsystem now uses the `time` CSR as the primary timestamp source, abandoning the hardcoded `cycle` frequency assumption.
- Timer rate is read from `timebase-frequency` in the DTB when accessible; otherwise, a fallback value is used with a RELATIVE trust level.
- Integrated the SBI TIME extension for one-shot timer deadlines, ensuring re-arming occurs after each tick to avoid missing heartbeats.
Verified: riscv64 builds clean, boots to the ok> prompt with no regression; `riscv64/timer.c` reports accurate frequencies on QEMU's default firmware.
Signed-off-by: Robert Allan James <robert.allan.james@gmail.com>
