An ASUS TUF A15 booted with its internal keyboard dead and a USB one
fine. These AMD laptops' firmware describes IRQ 1's polarity wrongly --
Linux keeps a quirk list -- and an edge line programmed the wrong way
up never fires: the controller holds its byte, and only the interrupt
that never comes would read it.
irq_watch() lets a driver say how to ask its device whether something
is waiting. The poller asks every tick; 50 ms of waiting with nothing
delivered turns the line's polarity over and drains the device, which
re-arms the edge, and if it still says nothing the line is polled.
Both are announced. The keyboard and the PS/2 mouse are watched.
ISA lines now also take their mode from the MADT's override entries,
which were parsed and never read.
Tested in QEMU, which ignores polarity on edge lines, with the keyboard
line masked: the first key turns it over and typing works; masked again
after the flip, it is polled and typing still works.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S1giNvrHTrPMPw7V6x1kQ4
- schinit, schinitd and vgpud build every message from pieces, one
write() each, so a job starting on another CPU landed mid-line:
"schinitd: starting vgpud: os.schos.resolvconfno virtio-gpu on this
machine". They now collect a line and write it at the newline;
resolvconf's verbose line is one write with its prefix.
- The ACPI SCI registers IRQ_QUIET. A desktop's SCI never fires, and the
poller took two seconds of silence for a misrouted line ("irq 9:
nothing has arrived on it") and called the handler every tick. A line
is only exempt while every handler on it is quiet.
- The loader claims each segment from where the last one's claim ended,
so two segments sharing a page no longer ask for it twice. When a
claim is still refused, it names the memory-map entries in the way.
- Stale divesymlink() declaration gone; the kernel.md struct table
re-measured (inode, buf and file pools grow from slabs now).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S1giNvrHTrPMPw7V6x1kQ4
Sixty-five headers sat side by side in include/, so `#include "irq.h"`
said nothing about where irq.h was or what it belonged to, and errno.h,
stat.h and fcntl.h at the top shadowed the system's for any host tool
built with -I./include. They are in folders now -- arch/ core/ fs/
dev/ gfx/ net/ uapi/ (and ldls/ for the Linux driver layer) -- and
every include names the folder, as Linux's do: "core/proc.h".
Done mechanically and checked the hard way: the kernel built from this
tree disassembles identically to the one built from the tree before
it. The full image boots, and userland is the same set of programs.
Paths in docs and comments follow; docs/guides/layout.md has a table
of what is where, and tools/fix-includes.py rewrites old-style
includes from the folders in the tree, for code written before this.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S1giNvrHTrPMPw7V6x1kQ4
