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Diffstat (limited to 'arch/x86/kernel/apic/apic.c')
-rw-r--r--arch/x86/kernel/apic/apic.c89
1 files changed, 55 insertions, 34 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index fb7657822aa..316a3b6b112 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1532,13 +1532,60 @@ static int __init detect_init_APIC(void)
return 0;
}
#else
+
+static int apic_verify(void)
+{
+ u32 features, h, l;
+
+ /*
+ * The APIC feature bit should now be enabled
+ * in `cpuid'
+ */
+ features = cpuid_edx(1);
+ if (!(features & (1 << X86_FEATURE_APIC))) {
+ pr_warning("Could not enable APIC!\n");
+ return -1;
+ }
+ set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
+ mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
+
+ /* The BIOS may have set up the APIC at some other address */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (l & MSR_IA32_APICBASE_ENABLE)
+ mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
+
+ pr_info("Found and enabled local APIC!\n");
+ return 0;
+}
+
+int apic_force_enable(void)
+{
+ u32 h, l;
+
+ if (disable_apic)
+ return -1;
+
+ /*
+ * Some BIOSes disable the local APIC in the APIC_BASE
+ * MSR. This can only be done in software for Intel P6 or later
+ * and AMD K7 (Model > 1) or later.
+ */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (!(l & MSR_IA32_APICBASE_ENABLE)) {
+ pr_info("Local APIC disabled by BIOS -- reenabling.\n");
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ enabled_via_apicbase = 1;
+ }
+ return apic_verify();
+}
+
/*
* Detect and initialize APIC
*/
static int __init detect_init_APIC(void)
{
- u32 h, l, features;
-
/* Disabled by kernel option? */
if (disable_apic)
return -1;
@@ -1568,38 +1615,12 @@ static int __init detect_init_APIC(void)
"you can enable it with \"lapic\"\n");
return -1;
}
- /*
- * Some BIOSes disable the local APIC in the APIC_BASE
- * MSR. This can only be done in software for Intel P6 or later
- * and AMD K7 (Model > 1) or later.
- */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (!(l & MSR_IA32_APICBASE_ENABLE)) {
- pr_info("Local APIC disabled by BIOS -- reenabling.\n");
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
- wrmsr(MSR_IA32_APICBASE, l, h);
- enabled_via_apicbase = 1;
- }
- }
- /*
- * The APIC feature bit should now be enabled
- * in `cpuid'
- */
- features = cpuid_edx(1);
- if (!(features & (1 << X86_FEATURE_APIC))) {
- pr_warning("Could not enable APIC!\n");
- return -1;
+ if (apic_force_enable())
+ return -1;
+ } else {
+ if (apic_verify())
+ return -1;
}
- set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
- mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
-
- /* The BIOS may have set up the APIC at some other address */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (l & MSR_IA32_APICBASE_ENABLE)
- mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
-
- pr_info("Found and enabled local APIC!\n");
apic_pm_activate();
@@ -1687,7 +1708,7 @@ void __init init_apic_mappings(void)
* This initializes the IO-APIC and APIC hardware if this is
* a UP kernel.
*/
-int apic_version[MAX_APICS];
+int apic_version[MAX_LOCAL_APIC];
int __init APIC_init_uniprocessor(void)
{