Re: [PATCH] x86 reboot: Remove inb_p usage

From: Ray Lee
Date: Sat Jan 19 2008 - 12:00:53 EST


On Jan 19, 2008 7:44 AM, Alan Cox <alan@xxxxxxxxxxxxxxxxxxx> wrote:
> We are driving a motherboard port so use a 2uS explicit delay at this
> point.
>
> Signed-off-by: Alan Cox <alan@xxxxxxxxxx>
>
> diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.24-rc8-mm1/arch/x86/kernel/reboot.c linux-2.6.24-rc8-mm1/arch/x86/kernel/reboot.c
> --- linux.vanilla-2.6.24-rc8-mm1/arch/x86/kernel/reboot.c 2008-01-19 14:47:55.000000000 +0000
> +++ linux-2.6.24-rc8-mm1/arch/x86/kernel/reboot.c 2008-01-19 14:53:58.000000000 +0000
> @@ -319,9 +319,11 @@
> {
> int i;
>
> - for (i = 0; i < 0x10000; i++)
> - if ((inb_p(0x64) & 0x02) == 0)
> + for (i = 0; i < 0x10000; i++) {
> + if ((inb(0x64) & 0x02) == 0)
> break;
> + udelay(2);
> + }
> }
>
> void machine_emergency_restart(void)

Stupid question from the peanut gallery: If you're going to go through
all this, maybe it would be better to define an inline
isa_bus_delay(void) { udelay(2); } and use that instead? I can only
imagine some poor sod coming along later and wondering why there's a
udelay(2) there. OTOH, there is an inb right above it, so <shrug>.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/