arch/x86/kernel/smpboot_64.c

   1 /*
   2  *      x86 SMP booting functions
   3  *
   4  *      (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
   5  *      (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
   6  *      Copyright 2001 Andi Kleen, SuSE Labs.
   7  *
   8  *      Much of the core SMP work is based on previous work by Thomas Radke, to
   9  *      whom a great many thanks are extended.
  10  *
  11  *      Thanks to Intel for making available several different Pentium,
  12  *      Pentium Pro and Pentium-II/Xeon MP machines.
  13  *      Original development of Linux SMP code supported by Caldera.
  14  *
  15  *      This code is released under the GNU General Public License version 2
  16  *
  17  *      Fixes
  18  *              Felix Koop      :       NR_CPUS used properly
  19  *              Jose Renau      :       Handle single CPU case.
  20  *              Alan Cox        :       By repeated request 8) - Total BogoMIP report.
  21  *              Greg Wright     :       Fix for kernel stacks panic.
  22  *              Erich Boleyn    :       MP v1.4 and additional changes.
  23  *      Matthias Sattler        :       Changes for 2.1 kernel map.
  24  *      Michel Lespinasse       :       Changes for 2.1 kernel map.
  25  *      Michael Chastain        :       Change trampoline.S to gnu as.
  26  *              Alan Cox        :       Dumb bug: 'B' step PPro's are fine
  27  *              Ingo Molnar     :       Added APIC timers, based on code
  28  *                                      from Jose Renau
  29  *              Ingo Molnar     :       various cleanups and rewrites
  30  *              Tigran Aivazian :       fixed "0.00 in /proc/uptime on SMP" bug.
  31  *      Maciej W. Rozycki       :       Bits for genuine 82489DX APICs
  32  *      Andi Kleen              :       Changed for SMP boot into long mode.
  33  *              Rusty Russell   :       Hacked into shape for new "hotplug" boot process.
  34  *      Andi Kleen              :       Converted to new state machine.
  35  *                                      Various cleanups.
  36  *                                      Probably mostly hotplug CPU ready now.
  37  *      Ashok Raj                       : CPU hotplug support
  38  */
  39
  40
  41 #include <linux/init.h>
  42
  43 #include <linux/mm.h>
  44 #include <linux/kernel_stat.h>
  45 #include <linux/bootmem.h>
  46 #include <linux/thread_info.h>
  47 #include <linux/module.h>
  48 #include <linux/delay.h>
  49 #include <linux/mc146818rtc.h>
  50 #include <linux/smp.h>
  51 #include <linux/kdebug.h>
  52
  53 #include <asm/mtrr.h>
  54 #include <asm/pgalloc.h>
  55 #include <asm/desc.h>
  56 #include <asm/tlbflush.h>
  57 #include <asm/proto.h>
  58 #include <asm/nmi.h>
  59 #include <asm/irq.h>
  60 #include <asm/hw_irq.h>
  61 #include <asm/numa.h>
  62
  63 #include <mach_wakecpu.h>
  64 #include <mach_apic.h>
  65 #include <smpboot_hooks.h>
  66 #include <mach_apic.h>
  67
  68 /* Set when the idlers are all forked */
  69 int smp_threads_ready;
  70
  71 cycles_t cacheflush_time;
  72 unsigned long cache_decay_ticks;
  73
  74 static int boot_cpu_logical_apicid;
  75 /*
  76  * Fall back to non SMP mode after errors.
  77  *
  78  * RED-PEN audit/test this more. I bet there is more state messed up here.
  79  */
  80 static __init void disable_smp(void)
  81 {
  82         cpu_present_map = cpumask_of_cpu(0);
  83         cpu_possible_map = cpumask_of_cpu(0);
  84         if (smp_found_config)
  85                 phys_cpu_present_map =
  86                                 physid_mask_of_physid(boot_cpu_physical_apicid);
  87         else
  88                 phys_cpu_present_map = physid_mask_of_physid(0);
  89         cpu_set(0, per_cpu(cpu_sibling_map, 0));
  90         cpu_set(0, per_cpu(cpu_core_map, 0));
  91 }
  92
  93 /*
  94  * Various sanity checks.
  95  */
  96 static int __init smp_sanity_check(unsigned max_cpus)
  97 {
  98         if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
  99                 printk("weird, boot CPU (#%d) not listed by the BIOS.\n",
 100                        hard_smp_processor_id());
 101                 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
 102         }
 103
 104         /*
 105          * If we couldn't find an SMP configuration at boot time,
 106          * get out of here now!
 107          */
 108         if (!smp_found_config) {
 109                 printk(KERN_NOTICE "SMP motherboard not detected.\n");
 110                 disable_smp();
 111                 if (APIC_init_uniprocessor())
 112                         printk(KERN_NOTICE "Local APIC not detected."
 113                                            " Using dummy APIC emulation.\n");
 114                 return -1;
 115         }
 116
 117         /*
 118          * Should not be necessary because the MP table should list the boot
 119          * CPU too, but we do it for the sake of robustness anyway.
 120          */
 121         if (!physid_isset(boot_cpu_physical_apicid, phys_cpu_present_map)) {
 122                 printk(KERN_NOTICE
 123                         "weird, boot CPU (#%d) not listed by the BIOS.\n",
 124                         boot_cpu_physical_apicid);
 125                 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
 126         }
 127
 128         /*
 129          * If we couldn't find a local APIC, then get out of here now!
 130          */
 131         if (!cpu_has_apic) {
 132                 printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
 133                         boot_cpu_physical_apicid);
 134                 printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
 135                 nr_ioapics = 0;
 136                 return -1;
 137         }
 138
 139         /*
 140          * If SMP should be disabled, then really disable it!
 141          */
 142         if (!max_cpus) {
 143                 printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");
 144                 nr_ioapics = 0;
 145                 return -1;
 146         }
 147
 148         return 0;
 149 }
 150
 151 static void __init smp_cpu_index_default(void)
 152 {
 153         int i;
 154         struct cpuinfo_x86 *c;
 155
 156         for_each_cpu_mask(i, cpu_possible_map) {
 157                 c = &cpu_data(i);
 158                 /* mark all to hotplug */
 159                 c->cpu_index = NR_CPUS;
 160         }
 161 }
 162
 163 /*
 164  * Prepare for SMP bootup.  The MP table or ACPI has been read
 165  * earlier.  Just do some sanity checking here and enable APIC mode.
 166  */
 167 void __init native_smp_prepare_cpus(unsigned int max_cpus)
 168 {
 169         nmi_watchdog_default();
 170         smp_cpu_index_default();
 171         cpu_callin_map = cpumask_of_cpu(0);
 172         mb();
 173
 174         current_cpu_data = boot_cpu_data;
 175         boot_cpu_logical_apicid = logical_smp_processor_id();
 176         current_thread_info()->cpu = 0;  /* needed? */
 177         set_cpu_sibling_map(0);
 178
 179         if (smp_sanity_check(max_cpus) < 0) {
 180                 printk(KERN_INFO "SMP disabled\n");
 181                 disable_smp();
 182                 return;
 183         }
 184
 185         if (GET_APIC_ID(apic_read(APIC_ID)) != boot_cpu_physical_apicid) {
 186                 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
 187                      GET_APIC_ID(apic_read(APIC_ID)), boot_cpu_physical_apicid);
 188                 /* Or can we switch back to PIC here? */
 189         }
 190
 191         /*
 192          * Switch from PIC to APIC mode.
 193          */
 194         setup_local_APIC();
 195
 196         /*
 197          * Enable IO APIC before setting up error vector
 198          */
 199         if (!skip_ioapic_setup && nr_ioapics)
 200                 enable_IO_APIC();
 201         end_local_APIC_setup();
 202
 203         /*
 204          * Set up local APIC timer on boot CPU.
 205          */
 206
 207         setup_boot_clock();
 208         printk(KERN_INFO "CPU%d: ", 0);
 209         print_cpu_info(&cpu_data(0));
 210 }