asgardius/android_kernel_motorola_sm6225
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

x86, apic: use physical mode for IBM summit platforms

Browse source 
Chris McDermott from IBM confirmed that hurricane chipset in IBM summit
platforms doesn't support logical flat mode.  Irrespective of the other
things like apic_id's, total number of logical cpu's, Linux kernel
should default to physical mode for this system.

The 32-bit kernel does so using the OEM checks for the IBM summit
platform.  Add a similar OEM platform check for the 64bit kernel too.

Otherwise the linux kernel boot can hang on this platform under certain
bios/platform settings.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Chris McDermott <lcm@linux.vnet.ibm.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Suresh Siddha 2010-01-18 12:10:48 -08:00 committed by Linus Torvalds
parent 54ef91dcf0
commit dfea91d5a7
1 changed files with 5 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
arch/x86/kernel/apic/apic_flat_64.c
View file

@ -240,6 +240,11 @@ static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
printk(KERN_DEBUG "system APIC only can use physical flat");
return 1;
}
if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
return 1;
}
#endif
return 0;