/* * This initializes the IO-APIC and APIC hardware if this is * a UP kernel. */ int __init APIC_init_uniprocessor(void) { if (disable_apic) { printk(KERN_INFO "Apic disabled\n"); return -1; } if (!cpu_has_apic) { disable_apic = 1; printk(KERN_INFO "Apic disabled by BIOS\n"); return -1; } verify_local_APIC(); connect_bsp_APIC(); physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map); apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid)); setup_local_APIC(); /* * Now enable IO-APICs, actually call clear_IO_APIC * We need clear_IO_APIC before enabling vector on BP */ if (!skip_ioapic_setup && nr_ioapics) enable_IO_APIC(); if (!smp_found_config || skip_ioapic_setup || !nr_ioapics) localise_nmi_watchdog(); end_local_APIC_setup(); if (smp_found_config && !skip_ioapic_setup && nr_ioapics) setup_IO_APIC(); else nr_ioapics = 0; setup_boot_APIC_clock(); check_nmi_watchdog(); return 0; }
/* * Report back to the Boot Processor during boot time or to the caller processor * during CPU online. */ static void __cpuinit smp_callin(void) { int cpuid, phys_id; unsigned long timeout; /* * If waken up by an INIT in an 82489DX configuration * we may get here before an INIT-deassert IPI reaches * our local APIC. We have to wait for the IPI or we'll * lock up on an APIC access. * * Since CPU0 is not wakened up by INIT, it doesn't wait for the IPI. */ cpuid = smp_processor_id(); if (apic->wait_for_init_deassert && cpuid != 0) apic->wait_for_init_deassert(&init_deasserted); /* * (This works even if the APIC is not enabled.) */ phys_id = read_apic_id(); if (cpumask_test_cpu(cpuid, cpu_callin_mask)) { panic("%s: phys CPU#%d, CPU#%d already present??\n", __func__, phys_id, cpuid); } pr_debug("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id); /* * STARTUP IPIs are fragile beasts as they might sometimes * trigger some glue motherboard logic. Complete APIC bus * silence for 1 second, this overestimates the time the * boot CPU is spending to send the up to 2 STARTUP IPIs * by a factor of two. This should be enough. */ /* * Waiting 2s total for startup (udelay is not yet working) */ timeout = jiffies + 2*HZ; while (time_before(jiffies, timeout)) { /* * Has the boot CPU finished it's STARTUP sequence? */ if (cpumask_test_cpu(cpuid, cpu_callout_mask)) break; cpu_relax(); } if (!time_before(jiffies, timeout)) { panic("%s: CPU%d started up but did not get a callout!\n", __func__, cpuid); } /* * the boot CPU has finished the init stage and is spinning * on callin_map until we finish. We are free to set up this * CPU, first the APIC. (this is probably redundant on most * boards) */ pr_debug("CALLIN, before setup_local_APIC()\n"); if (apic->smp_callin_clear_local_apic) apic->smp_callin_clear_local_apic(); setup_local_APIC(); end_local_APIC_setup(); /* * Need to setup vector mappings before we enable interrupts. */ setup_vector_irq(smp_processor_id()); /* * Save our processor parameters. Note: this information * is needed for clock calibration. */ smp_store_cpu_info(cpuid); /* * Get our bogomips. * Update loops_per_jiffy in cpu_data. Previous call to * smp_store_cpu_info() stored a value that is close but not as * accurate as the value just calculated. */ calibrate_delay(); cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy; pr_debug("Stack at about %p\n", &cpuid); /* * This must be done before setting cpu_online_mask * or calling notify_cpu_starting. */ set_cpu_sibling_map(raw_smp_processor_id()); wmb(); notify_cpu_starting(cpuid); /* * Allow the master to continue. */ cpumask_set_cpu(cpuid, cpu_callin_mask); }
/* * Report back to the Boot Processor during boot time or to the caller processor * during CPU online. */ static void smp_callin(void) { int cpuid, phys_id; /* * If waken up by an INIT in an 82489DX configuration * we may get here before an INIT-deassert IPI reaches * our local APIC. We have to wait for the IPI or we'll * lock up on an APIC access. * * Since CPU0 is not wakened up by INIT, it doesn't wait for the IPI. */ cpuid = smp_processor_id(); if (apic->wait_for_init_deassert && cpuid) while (!atomic_read(&init_deasserted)) cpu_relax(); /* * (This works even if the APIC is not enabled.) */ phys_id = read_apic_id(); /* * the boot CPU has finished the init stage and is spinning * on callin_map until we finish. We are free to set up this * CPU, first the APIC. (this is probably redundant on most * boards) */ pr_debug("CALLIN, before setup_local_APIC()\n"); if (apic->smp_callin_clear_local_apic) apic->smp_callin_clear_local_apic(); setup_local_APIC(); end_local_APIC_setup(); /* * Need to setup vector mappings before we enable interrupts. */ setup_vector_irq(smp_processor_id()); /* * Save our processor parameters. Note: this information * is needed for clock calibration. */ smp_store_cpu_info(cpuid); /* * Get our bogomips. * Update loops_per_jiffy in cpu_data. Previous call to * smp_store_cpu_info() stored a value that is close but not as * accurate as the value just calculated. */ calibrate_delay(); cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy; pr_debug("Stack at about %p\n", &cpuid); /* * This must be done before setting cpu_online_mask * or calling notify_cpu_starting. */ set_cpu_sibling_map(raw_smp_processor_id()); wmb(); notify_cpu_starting(cpuid); /* * Allow the master to continue. */ cpumask_set_cpu(cpuid, cpu_callin_mask); }
int __init APIC_init_uniprocessor(void) { if (disable_apic) { pr_info("Apic disabled\n"); return -1; } #ifdef CONFIG_X86_64 if (!cpu_has_apic) { disable_apic = 1; pr_info("Apic disabled by BIOS\n"); return -1; } #else if (!smp_found_config && !cpu_has_apic) return -1; if (!cpu_has_apic && APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) { pr_err("BIOS bug, local APIC 0x%x not detected!...\n", boot_cpu_physical_apicid); return -1; } #endif enable_IR_x2apic(); #ifdef CONFIG_X86_64 default_setup_apic_routing(); #endif verify_local_APIC(); connect_bsp_APIC(); #ifdef CONFIG_X86_64 apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid)); #else # ifdef CONFIG_CRASH_DUMP boot_cpu_physical_apicid = read_apic_id(); # endif #endif physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map); setup_local_APIC(); #ifdef CONFIG_X86_IO_APIC if (!skip_ioapic_setup && nr_ioapics) enable_IO_APIC(); #endif end_local_APIC_setup(); #ifdef CONFIG_X86_IO_APIC if (smp_found_config && !skip_ioapic_setup && nr_ioapics) setup_IO_APIC(); else { nr_ioapics = 0; localise_nmi_watchdog(); } #else localise_nmi_watchdog(); #endif x86_init.timers.setup_percpu_clockev(); #ifdef CONFIG_X86_64 check_nmi_watchdog(); #endif return 0; }