aboutsummaryrefslogtreecommitdiff
path: root/arch/x86_64
diff options
context:
space:
mode:
authorShaohua Li2005-11-05 17:25:54 +0100
committerLinus Torvalds2005-11-14 19:55:16 -0800
commitaf9c142de94ecf724a18700273bbba390873e072 (patch)
tree12ecf9850dc75c19cca7a14233d5ba3efe7dbb9d /arch/x86_64
parent1d2e6bd86152ab86fb866555281869df340e6c6a (diff)
[PATCH] x86_64: Force correct address space size for MTRR on some 64bit Intel Xeons
They report 40bit, but only have 36bits of physical address space. This caused problems with setting up the correct masks for MTRR. CPUID workaround for steppings 0F33h(supporting x86) and 0F34h(supporting x86 and EM64T). Detail info can be found at: http://download.intel.com/design/Xeon/specupdt/30240216.pdf http://download.intel.com/design/Pentium4/specupdt/30235221.pdf Signed-off-by: Shaohua Li<shaohua.li@intel.com> Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/x86_64')
-rw-r--r--arch/x86_64/kernel/setup.c5
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index 2ad3556dda52..476ee034fca2 100644
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -995,6 +995,11 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
unsigned eax = cpuid_eax(0x80000008);
c->x86_virt_bits = (eax >> 8) & 0xff;
c->x86_phys_bits = eax & 0xff;
+ /* CPUID workaround for Intel 0F34 CPU */
+ if (c->x86_vendor == X86_VENDOR_INTEL &&
+ c->x86 == 0xF && c->x86_model == 0x3 &&
+ c->x86_mask == 0x4)
+ c->x86_phys_bits = 36;
}
if (c->x86 == 15)