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[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>
hifive-unleashed-5.1
Shaohua Li 2005-11-05 17:25:54 +01:00 committed by Linus Torvalds
parent 1d2e6bd861
commit af9c142de9
2 changed files with 13 additions and 0 deletions
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8
arch/i386/kernel/cpu/mtrr/main.c
View File

@ -626,6 +626,14 @@ void __init mtrr_bp_init(void)
if (cpuid_eax(0x80000000) >= 0x80000008) {
u32 phys_addr;
phys_addr = cpuid_eax(0x80000008) & 0xff;
/* CPUID workaround for Intel 0F33/0F34 CPU */
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
boot_cpu_data.x86 == 0xF &&
boot_cpu_data.x86_model == 0x3 &&
(boot_cpu_data.x86_mask == 0x3 ||
boot_cpu_data.x86_mask == 0x4))
phys_addr = 36;
size_or_mask = ~((1 << (phys_addr - PAGE_SHIFT)) - 1);
size_and_mask = ~size_or_mask & 0xfff00000;
} else if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR &&

5
arch/x86_64/kernel/setup.c
View File

@ -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)