On Sun, Jun 21, 2009 at 10:14:13PM -0400, Pavel Roskin wrote: > On Sun, 2009-06-21 at 21:25 +0200, Robert Millan wrote: > > On Sun, Jun 21, 2009 at 03:05:56PM -0400, Pavel Roskin wrote: > > > On Sun, 2009-06-21 at 20:54 +0200, Robert Millan wrote: > > > > Move grub_stop to init.c to ease code sharing with i386-qemu. > > > > > > That's not quite a movement. grub_cpu_idle() does nothing. > > > > Well, the major problem with grub_cpu_idle() doing nothing on coreboot > > is CPU consumption during polls. grub_stop() is quite a corner case, > > only seen when you hit an error. > > I think this should do the right thing if our goal is to stop: > > cli > halt: > hlt > jmp halt > > The last "jmp" is just in case for non-maskable interrupts.
My aim was to move this to C code so it can be shared between i386-qemu and i386-coreboot. However, this code will be the same on other i386 ports, but we don't yet have a generic .S file for i386 code. How about kern/i386/misc.S ? > > grub_stop: Just hang. > > > > grub_exit: Exit to BIOS/whatever. On coreboot (and on i386-qemu) > > there's really no "proper" thing to do. Maybe fallback to > > grub_halt or grub_fatal. > > > > grub_halt: Power off. Theoretically we can have it anywhere, > > although in some platforms like coreboot it's not easy; otherwise > > it can fallback to grub_stop. > > > > I think grub_stop is intended to have this behaviour in all platforms. > > But I'm not sure how useful is it. Perhaps it could be ditched in > > favour of grub_exit? > > >From the user's standpoint, I think three "stop-like" calls make sense: > > Try to exit so that BIOS can try another media. Failing that, hang. > That would be appropriate for installations on disks that may or may not > be bootable. That's grub_exit(). > > Try for power down the system (that includes telling the emulator to > stop). Failing that, hang. That would be appropriate for data centers > where we don't want non-functioning systems to consume power. That's > grub_halt(). > > Just stop. Appropriate if there is an important message on the screen > that the user must see. This seems to be the current behaviour, unless I missed something. -- Robert Millan The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and how) you may access your data; but nobody's threatening your freedom: we still allow you to remove your data and not access it at all." _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org http://lists.gnu.org/mailman/listinfo/grub-devel
