diff options
Diffstat (limited to 'arch/x86/kernel/apic')
| -rw-r--r-- | arch/x86/kernel/apic/apic.c | 73 | ||||
| -rw-r--r-- | arch/x86/kernel/apic/io_apic.c | 4 |
2 files changed, 59 insertions, 18 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 07832363b729..2c07aebbb6f2 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -146,7 +146,8 @@ __setup("apicpmtimer", setup_apicpmtimer); int x2apic_mode; #ifdef CONFIG_X86_X2APIC /* x2apic enabled before OS handover */ -static int x2apic_preenabled; +int x2apic_preenabled; +static int x2apic_disabled; static __init int setup_nox2apic(char *str) { if (x2apic_enabled()) { @@ -1432,6 +1433,40 @@ void __init bsp_end_local_APIC_setup(void) } #ifdef CONFIG_X86_X2APIC +/* + * Need to disable xapic and x2apic at the same time and then enable xapic mode + */ +static inline void __disable_x2apic(u64 msr) +{ + wrmsrl(MSR_IA32_APICBASE, + msr & ~(X2APIC_ENABLE | XAPIC_ENABLE)); + wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE); +} + +static void disable_x2apic(void) +{ + u64 msr; + + if (!cpu_has_x2apic) + return; + + rdmsrl(MSR_IA32_APICBASE, msr); + if (msr & X2APIC_ENABLE) { + u32 x2apic_id = read_apic_id(); + + if (x2apic_id >= 255) + panic("Cannot disable x2apic, id: %08x\n", x2apic_id); + + pr_info("Disabling x2apic\n"); + __disable_x2apic(msr); + + x2apic_disabled = 1; + x2apic_mode = 0; + + register_lapic_address(mp_lapic_addr); + } +} + void check_x2apic(void) { if (x2apic_enabled()) { @@ -1442,15 +1477,20 @@ void check_x2apic(void) void enable_x2apic(void) { - int msr, msr2; + u64 msr; + + rdmsrl(MSR_IA32_APICBASE, msr); + if (x2apic_disabled) { + __disable_x2apic(msr); + return; + } if (!x2apic_mode) return; - rdmsr(MSR_IA32_APICBASE, msr, msr2); if (!(msr & X2APIC_ENABLE)) { printk_once(KERN_INFO "Enabling x2apic\n"); - wrmsr(MSR_IA32_APICBASE, msr | X2APIC_ENABLE, msr2); + wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE); } } #endif /* CONFIG_X86_X2APIC */ @@ -1487,7 +1527,7 @@ void __init enable_IR_x2apic(void) ret = save_ioapic_entries(); if (ret) { pr_info("Saving IO-APIC state failed: %d\n", ret); - goto out; + return; } local_irq_save(flags); @@ -1499,13 +1539,19 @@ void __init enable_IR_x2apic(void) else ret = enable_IR(); + if (!x2apic_supported()) + goto nox2apic; + if (ret < 0) { /* IR is required if there is APIC ID > 255 even when running * under KVM */ if (max_physical_apicid > 255 || - !hypervisor_x2apic_available()) + !hypervisor_x2apic_available()) { + if (x2apic_preenabled) + disable_x2apic(); goto nox2apic; + } /* * without IR all CPUs can be addressed by IOAPIC/MSI * only in physical mode @@ -1513,8 +1559,10 @@ void __init enable_IR_x2apic(void) x2apic_force_phys(); } - if (ret == IRQ_REMAP_XAPIC_MODE) + if (ret == IRQ_REMAP_XAPIC_MODE) { + pr_info("x2apic not enabled, IRQ remapping is in xapic mode\n"); goto nox2apic; + } x2apic_enabled = 1; @@ -1529,17 +1577,6 @@ nox2apic: restore_ioapic_entries(); legacy_pic->restore_mask(); local_irq_restore(flags); - -out: - if (x2apic_enabled || !x2apic_supported()) - return; - - if (x2apic_preenabled) - panic("x2apic: enabled by BIOS but kernel init failed."); - else if (ret == IRQ_REMAP_XAPIC_MODE) - pr_info("x2apic not enabled, IRQ remapping is in xapic mode\n"); - else if (ret < 0) - pr_info("x2apic not enabled, IRQ remapping init failed\n"); } #ifdef CONFIG_X86_64 diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 6d939d7847e2..45b461fdb344 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2948,6 +2948,10 @@ static inline void __init check_timer(void) } local_irq_disable(); apic_printk(APIC_QUIET, KERN_INFO "..... failed :(.\n"); + if (x2apic_preenabled) + apic_printk(APIC_QUIET, KERN_INFO + "Perhaps problem with the pre-enabled x2apic mode\n" + "Try booting with x2apic and interrupt-remapping disabled in the bios.\n"); panic("IO-APIC + timer doesn't work! Boot with apic=debug and send a " "report. Then try booting with the 'noapic' option.\n"); out: |