]> git.karo-electronics.de Git - karo-tx-linux.git/commit
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)
committerBen Hutchings <ben@decadent.org.uk>
Tue, 19 Jun 2012 22:18:05 +0000 (23:18 +0100)
commit161449f010c00726bb5384a1ae371433b8d625c7
treeb109709dbf682c5395dd94f8936c9ebeda3f4a48
parentcb60c34ea70a5e3e4cc6b76e0c1d2385efcaafc7
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>
(cherry picked from commit f7f286a910221ae18b21c18d9d0f4cd88965829f)

Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
arch/x86/kernel/cpu/amd.c