x86: make sure we really have an hpet mapping before using it

Impact: prepare the hpet code for Xen dom0 booting

When booting in Xen dom0, the hpet isn't really accessible, so make
sure the mapping is non-NULL before use.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Jeremy Fitzhardinge 2008-12-16 12:32:23 -08:00 committed by Ingo Molnar
parent bacbe99945
commit 39c04b5524
1 changed files with 3 additions and 2 deletions

View File

@ -834,10 +834,11 @@ static __init int hpet_late_init(void)
hpet_address = force_hpet_address;
hpet_enable();
if (!hpet_virt_address)
return -ENODEV;
}
if (!hpet_virt_address)
return -ENODEV;
hpet_reserve_platform_timers(hpet_readl(HPET_ID));
for_each_online_cpu(cpu) {