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build: the libavr pin advances past phase 6, at byte parity everywhere

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The pin crosses libavr's phase 6 - the renamed system surface, the named
serial configs, the receiver-tolerance table, the paged SPM receipts -
and every loader image comes out size-identical: the full matrix on six
representative chips (the exhaustive cross product on three of them),
the stock and autobaud columns untouched, the four tsb tiers back on
their recorded floors at 510/526/638/836.

Byte parity was not free, and the two libavr defects it surfaced were
fixed there rather than absorbed here. The EEPROM write procedure's
step 2 - the SPMEN spin - had landed unconditionally and cost every
build six bytes for a wait a polled loader can never take; it is scoped
now, and the loaders state the datasheet's own omission clause
(spm_interlock::omitted, DS40002061B 8.6.3). The blocking page
erase/write grew an internal wait the tiers' settle() already provides,
so the tiers issue the command form and pureboot keeps its host-driven
sp_spm path.

What the port states rather than inherits: the stock 115200 at 16 MHz
sits +2.1 % past the receiver-tolerance table libavr now holds rates
to, so the hardware links say .allow_baud_error = true - the same
2.5 % envelope pureboot_baud_feasible() has always enforced, proven on
silicon across the fleet. rx_ready() reads readable() now.

Alongside the pin: rule 33's ASCII sweep over every source (docs keep
their typography), rule 34's InsertBraces in .clang-format with the
tree reformatted, std::array over the simavr runners' raw buffers, and
the stale Studio size in ide/README.md replaced by the claim its
check-flags gate actually holds.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
BlackMark
2026-08-09 11:43:44 +02:00
parent 0cb83ff36f
commit e4390d2ba8
38 changed files with 791 additions and 625 deletions
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24
test/pbautobaud.py
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@@ -1,15 +1,15 @@
#!/usr/bin/env python3
"""End-to-end autobaud test: drive an autobaud loader in simavr through the
calibration handshake and a flash + EEPROM + fuse round-trip, cross-checked
against the simulator's ground-truth memory — then repeat at a second F_CPU with
against the simulator's ground-truth memory - then repeat at a second F_CPU with
the *same* loader binary, which is the property autobaud exists for: one
clock-agnostic image that locks onto whatever rate the host sends.
Usage: pbautobaud.py <device_bin> <loader_elf> <mcu> <base_hex> <page>
<app_bin> <app_hz> <app_baud> <tool_py> <workdir> [link]
The loader is a software-serial build, driven over the GPIO⇄pty bridge; the
optional link overrides the default -l sw:B0,B1 — RX == TX in it is the
The loader is a software-serial build, driven over the GPIO<->pty bridge; the
optional link overrides the default -l sw:B0,B1 - RX == TX in it is the
one-wire deployment, and every session then runs with the host's echo
discard on. The app fixture is built for (app_hz, app_baud); the hand-over
is checked at that point, and a second point at half the clock proves the
@@ -45,7 +45,7 @@ def main():
open(ee_path, "wb").write(ee_image)
# The geometry the surgery planner needs, from the chip class the runner is
# told — the same derivation pbtest.py makes: the boot-sectioned megas need
# told - the same derivation pbtest.py makes: the boot-sectioned megas need
# no vector surgery, the tinies and the boot-section-less m48s do, and the
# large chips speak word addresses.
mega = mcu.startswith("atmega")
@@ -74,7 +74,7 @@ def main():
# must land inside the
# encoding's own envelope: the loader floors the bit period to
# 4-cycle spin granules after an 8-cycle discount, and the edge
# poll can shave a few cycles more — one granule of slack below
# poll can shave a few cycles more - one granule of slack below
# the true clock, none above (in cycles per bit, times the rate).
measured = re.search(r"measured\s+(\d+) Hz", out)
if not measured:
@@ -96,8 +96,8 @@ def main():
if hand_over:
# Regression: a calibration pulse with no knock behind it must
# not wedge the loader. The knock's edge wait used to be
# unbudgeted, so one stray low pulse — EMI, or a host that opens
# the port and never knocks — held the loader forever and the
# unbudgeted, so one stray low pulse - EMI, or a host that opens
# the port and never knocks - held the loader forever and the
# application never ran. The whole activation is bounded now, so
# the window closes and the app boots; the banner is the proof.
# (The pause lets the loader reach its measurement loop, so the
@@ -111,13 +111,13 @@ def main():
port.write(bytes((pb.CALIBRATE,)))
# Accumulate rather than match exactly: the reset leaves the
# idle line a framing artefact ahead of the banner, which is
# noise here — the question is only whether the app ran.
# noise here - the question is only whether the app ran.
seen = b""
deadline = time.monotonic() + 180.0
while b"APP" not in seen and time.monotonic() < deadline:
seen += port.read_available(1.0)
if b"APP" not in seen:
fail(f"{label}: lone calibration pulse wedged the loader — app never bannered, saw {seen!r}")
fail(f"{label}: lone calibration pulse wedged the loader - app never bannered, saw {seen!r}")
print(f" {label}: lone calibration pulse does not wedge the loader")
finally:
port.close()
@@ -165,7 +165,7 @@ def main():
+ (", hand-over ok" if hand_over else ""))
def must_lock(hz, baud, label):
"""The calibration alone, at a tight bit period. Nothing is programmed —
"""The calibration alone, at a tight bit period. Nothing is programmed -
the question is only whether the loader can still measure the pulse."""
dump = os.path.join(workdir, f"flash_{label}.bin")
device = pbsim.Device(device_bin, elf, mcu, str(hz), base_hex, page, baud, dump,
@@ -186,7 +186,7 @@ def main():
# The app fixture is built for one clock; the hand-over banners there. A
# second point at double that clock, same loader binary, proves the lock is
# measured, not baked in — the whole point of autobaud. (Doubling keeps the
# measured, not baked in - the whole point of autobaud. (Doubling keeps the
# bit period healthy; halving would drop it below the software UART's floor.)
round_trip(app_hz, app_baud, "clock-a", hand_over=True)
round_trip(app_hz * 2, app_baud, "clock-b", hand_over=False)
@@ -194,7 +194,7 @@ def main():
# Both points above sit near 100 cycles a bit, which is comfortable. The
# calibration's real floor is far tighter, and it is worth a gate: measured
# here, the lock is solid down to ~36 cycles a bit and fails outright by ~31
# — a sharp edge, not a fraying one. This pins the tightest standard rate the
# - a sharp edge, not a fraying one. This pins the tightest standard rate the
# fixture's clock reaches, so a change that raises the floor is caught.
#
# It does *not* bound what a real deployment can use. On silicon the