* docs(mochabin): add EP06 mPCIe GPIO investigation runbook (ref #345)
scripts/probe-mpcie-gpios.sh: empirical CP0 GPIO sweep that drives
each unrequested line HIGH for a few seconds and watches dmesg/lsusb
for new USB device. Skips [used] lines, uses libgpiod gpioset
--mode=time so the line auto-restores to input on release. Modes:
--baseline (snapshot only, safe), --line gpiochipN K (single line),
no arg (full sweep gpiochip1+gpiochip2).
docs/hardware/mochabin-mpcie-ep06-runbook.md: hypothesis, procedure,
and DTS rfkill-gpio template patterned after cn9132-clearfog.dts
lines 69-122. Apply once a candidate GPIO is identified.
--baseline smoke-tested on gk2 — sweep deferred until spare EP06
arrives (no mPCIe device in J5 = no signal regardless of which line
drives W_DISABLE#).
* docs(mochabin): drop EP06 spare assumption from runbook (ref #345)
No spare EP06 on order; the existing EP06-E will be used for the
sweep when re-seated in J5. Replaces "deferred until spare" framing
with a multimeter-scoping fallback for the inconclusive case.
* fix(mpcie): v0.2.0 probe-mpcie-gpios.sh — drop blanket sweep, danger-list, dry-run default (ref #345)
The v0.1.0 "drive every unused-input CP0 GPIO HIGH for 3s one-at-a-time"
sweep took gk2 hard-down within seconds (host became unreachable; ARP
stopped responding). gpioinfo's [used] tag only reflects lines the
kernel *requested* — several unrequested CP0 GPIOs are physically
wired to critical board functions (eth switch reset, PCIe2 PERST#,
pca9554 IRQ) and driving them HIGH wedged the board.
v0.2.0:
- No blanket-sweep mode. Removed.
- Default mode = dry-run candidate listing only. No GPIO is driven.
- --commit --line CHIP N required to actually drive a single line.
- Hardcoded DANGER_LINES (gpiochip1:1, gpiochip1:9, gpiochip1:27)
skipped unconditionally, even with --commit.
- gpiochip2 entirely held off without --allow-chip2 (no per-line
schematic mapping for that bank).
- Hard refusals are vocal (REFUSED: ... reason) before exit.
Runbook updated to walk through the new dry-run → --commit flow.
HISTORY documents the incident + the v0.2.0 mitigations.
Lesson saved in memory feedback_gpio_blanket_sweep_crashed_board.md.
---------
Co-authored-by: CyberMind-FR <gandalf@Gk2.net>
