x86/amd: Re-enable CPU topology extensions in case BIOS has disabled it
authorAndreas Herrmann <andreas.herrmann3@amd.com>
Tue, 3 Apr 2012 10:13:07 +0000 (12:13 +0200)
committerIngo Molnar <mingo@kernel.org>
Fri, 27 Apr 2012 14:43:09 +0000 (16:43 +0200)
commitf7f286a910221ae18b21c18d9d0f4cd88965829f
treee2bb2aef9e9507f8b309b1ede63b2ea862d0f1ee
parentea0dcf903e7d76aa5d483d876215fedcfdfe140f
x86/amd: Re-enable CPU topology extensions in case BIOS has disabled it

BIOS will switch off the corresponding feature flag on family
15h models 10h-1fh non-desktop CPUs.

The topology extension CPUID leafs are required to detect which
cores belong to the same compute unit. (thread siblings mask is
set accordingly and also correct information about L1i and L2
cache sharing depends on this).

W/o this patch we wouldn't see which cores belong to the same
compute unit and also cache sharing information for L1i and L2
would be incorrect on such systems.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/kernel/cpu/amd.c