Re: [PATCH 3/3] i386: use ACPI to power off the machine

[Justus Winter]

Quoting Justus Winter (2014-05-03 01:33:14)
> This is a mostly verbatim copy of acpihalt.c from GRUB2 with a little
> bit of glue code.
> [...]
> * i386/i386at/acpihalt.c: Likewise.
> (grub_acpi_halt): Map physical addresses.

Hum.  Maybe I'm holding stuff wrong.  A little help please ;)

This works if I build a stock gnumach (w/o any device drivers), boot
it using qemu -kernel gnumach, get dropped into the kdb, I enter halt,
qemu powers down.

Setting GRUB_DEBUG to 1 (i386/i386at/grub_glue.c) enables all the
logging from grub_dprintf and friends.  Here is an excerpt from an
successful run:

db> halt
Looking for RSDP. Scanning EBDA
Looking for RSDP. Scanning BIOS
Looking for RSDP. Scanning EBDA
Looking for RSDP. Scanning BIOS
rsdp1=c00f19b0
rsdp1->rsdt_addr=7fffad3   (I added this to print the physical address of the 
table)
[...]

However, when I use --enable-device-drivers=qemu it doesn't work:

db> halt
Looking for RSDP. Scanning EBDA
Looking for RSDP. Scanning EBDA
rsdp1=0

Hum.  Maybe someone overwrote our precious EBDA table (whatever that
is).  It's supposed to be around physical address 0x40e.  See acpi.c
for the code looking for the RSDP.

Also, when I shut down a system that made it to userspace, I can see
this (with 60_bigmem.patch):

init: notifying pfinet of shutdown...init: notifying tmpfs none of
shutdown...init: notifying tmpfs none of shutdown...init: notifying
tmpfs none of shutdown...init: notifying ext2fs device:hd0s1 of
shutdown...init: halting Mach (flags 0x8)...

panic: pmap_enter(80000000, 36c3000) falls in physical memory area!

Cheers,
Justus