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Diffstat (limited to 'arch/x86/kernel/apic_64.c')
-rw-r--r--arch/x86/kernel/apic_64.c154
1 files changed, 150 insertions, 4 deletions
diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index d5c06917b5b..dd0501039f0 100644
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -27,6 +27,7 @@
#include <linux/clockchips.h>
#include <linux/acpi_pmtmr.h>
#include <linux/module.h>
+#include <linux/dmar.h>
#include <asm/atomic.h>
#include <asm/smp.h>
@@ -39,6 +40,7 @@
#include <asm/proto.h>
#include <asm/timex.h>
#include <asm/apic.h>
+#include <asm/i8259.h>
#include <mach_ipi.h>
#include <mach_apic.h>
@@ -46,8 +48,12 @@
static int disable_apic_timer __cpuinitdata;
static int apic_calibrate_pmtmr __initdata;
int disable_apic;
+int disable_x2apic;
int x2apic;
+/* x2apic enabled before OS handover */
+int x2apic_preenabled;
+
/* Local APIC timer works in C2 */
int local_apic_timer_c2_ok;
EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
@@ -896,6 +902,125 @@ void __cpuinit end_local_APIC_setup(void)
apic_pm_activate();
}
+void check_x2apic(void)
+{
+ int msr, msr2;
+
+ rdmsr(MSR_IA32_APICBASE, msr, msr2);
+
+ if (msr & X2APIC_ENABLE) {
+ printk("x2apic enabled by BIOS, switching to x2apic ops\n");
+ x2apic_preenabled = x2apic = 1;
+ apic_ops = &x2apic_ops;
+ }
+}
+
+void enable_x2apic(void)
+{
+ int msr, msr2;
+
+ rdmsr(MSR_IA32_APICBASE, msr, msr2);
+ if (!(msr & X2APIC_ENABLE)) {
+ printk("Enabling x2apic\n");
+ wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, 0);
+ }
+}
+
+void enable_IR_x2apic(void)
+{
+#ifdef CONFIG_INTR_REMAP
+ int ret;
+ unsigned long flags;
+
+ if (!cpu_has_x2apic)
+ return;
+
+ if (!x2apic_preenabled && disable_x2apic) {
+ printk(KERN_INFO
+ "Skipped enabling x2apic and Interrupt-remapping "
+ "because of nox2apic\n");
+ return;
+ }
+
+ if (x2apic_preenabled && disable_x2apic)
+ panic("Bios already enabled x2apic, can't enforce nox2apic");
+
+ if (!x2apic_preenabled && skip_ioapic_setup) {
+ printk(KERN_INFO
+ "Skipped enabling x2apic and Interrupt-remapping "
+ "because of skipping io-apic setup\n");
+ return;
+ }
+
+ ret = dmar_table_init();
+ if (ret) {
+ printk(KERN_INFO
+ "dmar_table_init() failed with %d:\n", ret);
+
+ if (x2apic_preenabled)
+ panic("x2apic enabled by bios. But IR enabling failed");
+ else
+ printk(KERN_INFO
+ "Not enabling x2apic,Intr-remapping\n");
+ return;
+ }
+
+ local_irq_save(flags);
+ mask_8259A();
+ save_mask_IO_APIC_setup();
+
+ ret = enable_intr_remapping(1);
+
+ if (ret && x2apic_preenabled) {
+ local_irq_restore(flags);
+ panic("x2apic enabled by bios. But IR enabling failed");
+ }
+
+ if (ret)
+ goto end;
+
+ if (!x2apic) {
+ x2apic = 1;
+ apic_ops = &x2apic_ops;
+ enable_x2apic();
+ }
+end:
+ if (ret)
+ /*
+ * IR enabling failed
+ */
+ restore_IO_APIC_setup();
+ else
+ reinit_intr_remapped_IO_APIC(x2apic_preenabled);
+
+ unmask_8259A();
+ local_irq_restore(flags);
+
+ if (!ret) {
+ if (!x2apic_preenabled)
+ printk(KERN_INFO
+ "Enabled x2apic and interrupt-remapping\n");
+ else
+ printk(KERN_INFO
+ "Enabled Interrupt-remapping\n");
+ } else
+ printk(KERN_ERR
+ "Failed to enable Interrupt-remapping and x2apic\n");
+#else
+ if (!cpu_has_x2apic)
+ return;
+
+ if (x2apic_preenabled)
+ panic("x2apic enabled prior OS handover,"
+ " enable CONFIG_INTR_REMAP");
+
+ printk(KERN_INFO "Enable CONFIG_INTR_REMAP for enabling intr-remapping "
+ " and x2apic\n");
+#endif
+
+ return;
+}
+
/*
* Detect and enable local APICs on non-SMP boards.
* Original code written by Keir Fraser.
@@ -943,6 +1068,11 @@ void __init early_init_lapic_mapping(void)
*/
void __init init_apic_mappings(void)
{
+ if (x2apic) {
+ boot_cpu_physical_apicid = GET_APIC_ID(read_apic_id());
+ return;
+ }
+
/*
* If no local APIC can be found then set up a fake all
* zeroes page to simulate the local APIC and another
@@ -981,6 +1111,9 @@ int __init APIC_init_uniprocessor(void)
return -1;
}
+ enable_IR_x2apic();
+ setup_apic_routing();
+
verify_local_APIC();
connect_bsp_APIC();
@@ -1238,10 +1371,14 @@ static int lapic_resume(struct sys_device *dev)
maxlvt = lapic_get_maxlvt();
local_irq_save(flags);
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
- wrmsr(MSR_IA32_APICBASE, l, h);
+ if (!x2apic) {
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ } else
+ enable_x2apic();
+
apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
apic_write(APIC_ID, apic_pm_state.apic_id);
apic_write(APIC_DFR, apic_pm_state.apic_dfr);
@@ -1381,6 +1518,15 @@ __cpuinit int apic_is_clustered_box(void)
return (clusters > 2);
}
+static __init int setup_nox2apic(char *str)
+{
+ disable_x2apic = 1;
+ clear_cpu_cap(&boot_cpu_data, X86_FEATURE_X2APIC);
+ return 0;
+}
+early_param("nox2apic", setup_nox2apic);
+
+
/*
* APIC command line parameters
*/