x86, ioapic: Fix the EOI register detection mechanism
x86, ioapic: Fix the EOI register detection mechanism

Maciej W. Rozycki reported:

> 82093AA I/O APIC has its version set to 0x11 and it
> does not support the EOI register.  Similarly I/O APICs
> integrated into the 82379AB south bridge and the 82374EB/SB
> EISA component.

IO-APIC versions below 0x20 don't support EOI register.

Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
version as 0x2. This is an error with documentation and these
ICH chips use io-apic's of version 0x20 and indeed has a working
EOI register for the io-apic.

Fix the EOI register detection mechanism to check for version
0x20 and beyond.

And also, a platform can potentially  have io-apic's with
different versions. Make the EOI register check per io-apic.

Reported-by: Maciej W. Rozycki <78f3a3d9d6e4d907a7d12e475d0a751d6b7e256b@linux-mips.org>
Signed-off-by: Suresh Siddha <a42fd12510d3895be740fb89f87586733ee62f57@intel.com>
Cc: 8a741aa8cbd77ebc4a56ddb528ce9fd15d42f034@xmission.com
Cc: a8dd1917ed02ab5cfb8e65fb725d13b854dee351@us.ibm.com
LKML-Reference: <7b7078efecdef7df82e11dfbc5b300a1b19e44da@sbs-t61.sc.intel.com>
Signed-off-by: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas