SchOS/boot/uefi
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Nexoniarz e659c6b187 bug pass: whole console lines, a quiet SCI, an honest reserve warning
- 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
2026-10-23 16:03:33 +02:00
..
efi.h display: a 64-bit framebuffer address, no mirroring onto itself 2026-10-23 15:46:42 +02:00
main.c bug pass: whole console lines, a quiet SCI, an honest reserve warning 2026-10-23 16:03:33 +02:00
README.md licence: SchOS is GPL-2.0-or-later, no longer Apache-2.0 2026-10-22 08:48:45 +02:00
startup.nsh boot/uefi: a working UEFI loader, with one known limitation 2026-08-09 17:13:09 +02:00

UEFI loader

The loader. This directory once existed only so the BIOS path could be moved into boot/bios/ without pretending the split was hypothetical; it is now the only path there is.

See ../README.md for the hand-off contract a loader has to satisfy. The short version: the kernel wants long mode with paging on, its ELF segments placed, a 24-byte-entry E820-shaped memory map, and framebuffer geometry — and it does not care which firmware produced them.

What this will need, in rough order:

  1. A PE/COFF target. clang can emit one directly (--target=x86_64-unknown-windows -fuse-ld=lld-link), so no new toolchain: the same LLVM install already builds every other target here.
  2. The handful of UEFI structures actually used — the system table, boot services, LOADED_IMAGE, SIMPLE_FILE_SYSTEM, GRAPHICS_OUTPUT. Written from the specification rather than by importing gnu-efi or EDK II, which is both a licence question and a large dependency for something this small.
  3. GetMemoryMap translated into the same 24-byte entries e820.c already parses. Not a second format for the kernel to learn.
  4. ExitBootServices before touching the memory it described.
  5. Graphics Output Protocol for the framebuffer, filling the same VBE_INFO_ADDR structure the kernel reads.

The image goes at EFI/BOOT/BOOTX64.EFI on a FAT ESP, which also means the ISO carries a single El Torito EFI entry.