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authorThomas Gleixner <tglx@linutronix.de>2008-05-08 09:18:43 +0200
committerIngo Molnar <mingo@elte.hu>2008-05-08 15:43:51 +0200
commit8d4a4300854f3971502e81dacd930704cb88f606 (patch)
treed091b49851e60af1530dd3d7cd54057f98d48ffb /arch/x86/kernel/cpu
parentcb3f43b22bbb5ddbf6ce3e2bac40ce6eba30aba0 (diff)
x86: cleanup PAT cpu validation
Move the scattered checks for PAT support to a single function. Its moved to addon_cpuid_features.c as this file is shared between 32 and 64 bit. Remove the manipulation of the PAT feature bit and just disable PAT in the PAT layer, based on the PAT bit provided by the CPU and the current CPU version/model white list. Change the boot CPU check so it works on Voyager somewhere in the future as well :) Also panic, when a secondary has PAT disabled but the primary one has alrady switched to PAT. We have no way to undo that. The white list is kept for now to ensure that we can rely on known to work CPU types and concentrate on the software induced problems instead of fighthing CPU erratas and subtle wreckage caused by not yet verified CPUs. Once the PAT code has stabilized enough, we can remove the white list and open the can of worms. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/cpu')
-rw-r--r--arch/x86/kernel/cpu/addon_cpuid_features.c21
-rw-r--r--arch/x86/kernel/cpu/common.c27
2 files changed, 23 insertions, 25 deletions
diff --git a/arch/x86/kernel/cpu/addon_cpuid_features.c b/arch/x86/kernel/cpu/addon_cpuid_features.c
index 238468ae199..c2e1ce33c7c 100644
--- a/arch/x86/kernel/cpu/addon_cpuid_features.c
+++ b/arch/x86/kernel/cpu/addon_cpuid_features.c
@@ -6,6 +6,7 @@
#include <linux/cpu.h>
+#include <asm/pat.h>
#include <asm/processor.h>
struct cpuid_bit {
@@ -48,3 +49,23 @@ void __cpuinit init_scattered_cpuid_features(struct cpuinfo_x86 *c)
set_cpu_cap(c, cb->feature);
}
}
+
+#ifdef CONFIG_X86_PAT
+void __cpuinit validate_pat_support(struct cpuinfo_x86 *c)
+{
+ switch (c->x86_vendor) {
+ case X86_VENDOR_AMD:
+ if (c->x86 >= 0xf && c->x86 <= 0x11)
+ return;
+ break;
+ case X86_VENDOR_INTEL:
+ if (c->x86 == 0xF || (c->x86 == 6 && c->x86_model >= 15))
+ return;
+ break;
+ }
+
+ pat_disable(cpu_has_pat ?
+ "PAT disabled. Not yet verified on this CPU type." :
+ "PAT not supported by CPU.");
+}
+#endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 35b4f6a9c8e..d0463a94624 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -12,6 +12,7 @@
#include <asm/mmu_context.h>
#include <asm/mtrr.h>
#include <asm/mce.h>
+#include <asm/pat.h>
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/mpspec.h>
#include <asm/apic.h>
@@ -308,19 +309,6 @@ static void __cpuinit early_get_cap(struct cpuinfo_x86 *c)
}
- clear_cpu_cap(c, X86_FEATURE_PAT);
-
- switch (c->x86_vendor) {
- case X86_VENDOR_AMD:
- if (c->x86 >= 0xf && c->x86 <= 0x11)
- set_cpu_cap(c, X86_FEATURE_PAT);
- break;
- case X86_VENDOR_INTEL:
- if (c->x86 == 0xF || (c->x86 == 6 && c->x86_model >= 15))
- set_cpu_cap(c, X86_FEATURE_PAT);
- break;
- }
-
}
/*
@@ -409,18 +397,6 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
init_scattered_cpuid_features(c);
}
- clear_cpu_cap(c, X86_FEATURE_PAT);
-
- switch (c->x86_vendor) {
- case X86_VENDOR_AMD:
- if (c->x86 >= 0xf && c->x86 <= 0x11)
- set_cpu_cap(c, X86_FEATURE_PAT);
- break;
- case X86_VENDOR_INTEL:
- if (c->x86 == 0xF || (c->x86 == 6 && c->x86_model >= 15))
- set_cpu_cap(c, X86_FEATURE_PAT);
- break;
- }
}
static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
@@ -651,6 +627,7 @@ void __init early_cpu_init(void)
cpu_devs[cvdev->vendor] = cvdev->cpu_dev;
early_cpu_detect();
+ validate_pat_support(&boot_cpu_data);
}
/* Make sure %fs is initialized properly in idle threads */