[SeaBIOS] [PATCH RFC 0/3] seabios: move acpi table formatting out of bios
Michael S. Tsirkin
mst at redhat.com
Thu Apr 25 11:02:20 CEST 2013
Untested yet, but I thought I'd share the
BIOS bits so we can agree on direction.
In particular check out ROM sizes:
- Before patchset with DSDT enabled
Total size: 127880 Fixed: 59060 Free: 3192 (used 97.6% of 128KiB rom)
- Before patchset with DSDT disabled
Total size: 122844 Fixed: 58884 Free: 8228 (used 93.7% of 128KiB rom)
- After patchset:
Total size: 128776 Fixed: 59100 Free: 2296 (used 98.2% of 128KiB rom)
- Legacy disabled at build time:
Total size: 119836 Fixed: 58996 Free: 11236 (used 91.4% of 128KiB rom)
As can be seen from this, most size savings come
from dropping DSDT, but we do save a bit by removing
other tables. Of course the real reason to move tables to QEMU
is so that ACPI can better match hardware.
This patchset adds an option to move all code for formatting acpi tables
out of BIOS. With this, QEMU has full control over the table layout.
All tables are loaded from the new "/etc/acpi/" directory.
Any entries in this directory cause BIOS to disable
ACPI table generation completely.
A generic linker script, controlled by QEMU, is
loaded from "/etc/linker-script". It is used to
patch in table pointers and checksums.
BIOS still has limited ability to parse the tables,
for the following purposes:
- locate resume vector
- allocate RSDP in FSEG
- allocate FACS at an aligned address
Michael S. Tsirkin (3):
linker: utility to patch in-memory ROM files
acpi: load and link tables from /etc/acpi/
acpi: add an option to disable builtin tables
Makefile | 2 +-
src/Kconfig | 12 +++++++-
src/acpi.c | 67 +++++++++++++++++++++++++++++++++++++++++++-
src/linker.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/linker.h | 50 +++++++++++++++++++++++++++++++++
src/util.h | 1 +
6 files changed, 219 insertions(+), 3 deletions(-)
create mode 100644 src/linker.c
create mode 100644 src/linker.h
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