/* Copyright 2003 Andi Kleen, SuSE Labs. * Subject to the GNU Public License, v.2 * * Generic x86 APIC driver probe layer. */ #include #include #include #include #include #include #include #include #include #include #include #include struct genapic __read_mostly genapic; static const struct genapic *const __initconstrel apic_probe[] = { &apic_bigsmp, &apic_default, /* must be last */ NULL, }; static bool __initdata forced_apic; void __init generic_bigsmp_probe(void) { /* * This routine is used to switch to bigsmp mode when * - There is no apic= option specified by the user * - generic_apic_probe() has choosen apic_default as the sub_arch * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support */ if (!forced_apic && genapic.name == apic_default.name) if (apic_bigsmp.probe()) { genapic = apic_bigsmp; printk(KERN_INFO "Overriding APIC driver with %s\n", genapic.name); } } static int __init cf_check genapic_apic_force(const char *str) { int i, rc = -EINVAL; for (i = 0; apic_probe[i]; i++) if (!strcmp(apic_probe[i]->name, str)) { genapic = *apic_probe[i]; rc = 0; } return rc; } custom_param("apic", genapic_apic_force); void __init generic_apic_probe(void) { int i; record_boot_APIC_mode(); check_x2apic_preenabled(); forced_apic = genapic.name; for (i = 0; !genapic.name && apic_probe[i]; i++) { if (!apic_probe[i]->probe || apic_probe[i]->probe()) genapic = *apic_probe[i]; } BUG_ON(!genapic.name); printk(KERN_INFO "Using APIC driver %s\n", genapic.name); }