arch/x86/kernel/irqinit.c

   1 #include <linux/linkage.h>
   2 #include <linux/errno.h>
   3 #include <linux/signal.h>
   4 #include <linux/sched.h>
   5 #include <linux/ioport.h>
   6 #include <linux/interrupt.h>
   7 #include <linux/timex.h>
   8 #include <linux/slab.h>
   9 #include <linux/random.h>
  10 #include <linux/kprobes.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel_stat.h>
  13 #include <linux/sysdev.h>
  14 #include <linux/bitops.h>
  15 #include <linux/acpi.h>
  16 #include <linux/io.h>
  17 #include <linux/delay.h>
  18
  19 #include <asm/atomic.h>
  20 #include <asm/system.h>
  21 #include <asm/timer.h>
  22 #include <asm/hw_irq.h>
  23 #include <asm/pgtable.h>
  24 #include <asm/desc.h>
  25 #include <asm/apic.h>
  26 #include <asm/setup.h>
  27 #include <asm/i8259.h>
  28 #include <asm/traps.h>
  29
  30 /*
  31  * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
  32  * (these are usually mapped to vectors 0x30-0x3f)
  33  */
  34
  35 /*
  36  * The IO-APIC gives us many more interrupt sources. Most of these
  37  * are unused but an SMP system is supposed to have enough memory ...
  38  * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
  39  * across the spectrum, so we really want to be prepared to get all
  40  * of these. Plus, more powerful systems might have more than 64
  41  * IO-APIC registers.
  42  *
  43  * (these are usually mapped into the 0x30-0xff vector range)
  44  */
  45
  46 #ifdef CONFIG_X86_32
  47 /*
  48  * Note that on a 486, we don't want to do a SIGFPE on an irq13
  49  * as the irq is unreliable, and exception 16 works correctly
  50  * (ie as explained in the intel literature). On a 386, you
  51  * can't use exception 16 due to bad IBM design, so we have to
  52  * rely on the less exact irq13.
  53  *
  54  * Careful.. Not only is IRQ13 unreliable, but it is also
  55  * leads to races. IBM designers who came up with it should
  56  * be shot.
  57  */
  58
  59 static irqreturn_t math_error_irq(int cpl, void *dev_id)
  60 {
  61         outb(0, 0xF0);
  62         if (ignore_fpu_irq || !boot_cpu_data.hard_math)
  63                 return IRQ_NONE;
  64         math_error((void __user *)get_irq_regs()->ip);
  65         return IRQ_HANDLED;
  66 }
  67
  68 /*
  69  * New motherboards sometimes make IRQ 13 be a PCI interrupt,
  70  * so allow interrupt sharing.
  71  */
  72 static struct irqaction fpu_irq = {
  73         .handler = math_error_irq,
  74         .name = "fpu",
  75 };
  76 #endif
  77
  78 /*
  79  * IRQ2 is cascade interrupt to second interrupt controller
  80  */
  81 static struct irqaction irq2 = {
  82         .handler = no_action,
  83         .name = "cascade",
  84 };
  85
  86 DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
  87         [0 ... NR_VECTORS - 1] = -1,
  88 };
  89
  90 int vector_used_by_percpu_irq(unsigned int vector)
  91 {
  92         int cpu;
  93
  94         for_each_online_cpu(cpu) {
  95                 if (per_cpu(vector_irq, cpu)[vector] != -1)
  96                         return 1;
  97         }
  98
  99         return 0;
 100 }
 101
 102 /* Number of legacy interrupts */
 103 int nr_legacy_irqs __read_mostly = NR_IRQS_LEGACY;
 104
 105 void __init init_ISA_irqs(void)
 106 {
 107         int i;
 108
 109 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
 110         init_bsp_APIC();
 111 #endif
 112         init_8259A(0);
 113
 114         /*
 115          * 16 old-style INTA-cycle interrupts:
 116          */
 117         for (i = 0; i < NR_IRQS_LEGACY; i++) {
 118                 struct irq_desc *desc = irq_to_desc(i);
 119
 120                 desc->status = IRQ_DISABLED;
 121                 desc->action = NULL;
 122                 desc->depth = 1;
 123
 124                 set_irq_chip_and_handler_name(i, &i8259A_chip,
 125                                               handle_level_irq, "XT");
 126         }
 127 }
 128
 129 void __init init_IRQ(void)
 130 {
 131         int i;
 132
 133         /*
 134          * On cpu 0, Assign IRQ0_VECTOR..IRQ15_VECTOR's to IRQ 0..15.
 135          * If these IRQ's are handled by legacy interrupt-controllers like PIC,
 136          * then this configuration will likely be static after the boot. If
 137          * these IRQ's are handled by more mordern controllers like IO-APIC,
 138          * then this vector space can be freed and re-used dynamically as the
 139          * irq's migrate etc.
 140          */
 141         for (i = 0; i < nr_legacy_irqs; i++)
 142                 per_cpu(vector_irq, 0)[IRQ0_VECTOR + i] = i;
 143
 144         x86_init.irqs.intr_init();
 145 }
 146
 147 static void __init smp_intr_init(void)
 148 {
 149 #ifdef CONFIG_SMP
 150 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
 151         /*
 152          * The reschedule interrupt is a CPU-to-CPU reschedule-helper
 153          * IPI, driven by wakeup.
 154          */
 155         alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
 156
 157         /* IPIs for invalidation */
 158         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+0, invalidate_interrupt0);
 159         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+1, invalidate_interrupt1);
 160         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+2, invalidate_interrupt2);
 161         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+3, invalidate_interrupt3);
 162         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+4, invalidate_interrupt4);
 163         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+5, invalidate_interrupt5);
 164         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+6, invalidate_interrupt6);
 165         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+7, invalidate_interrupt7);
 166
 167         /* IPI for generic function call */
 168         alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
 169
 170         /* IPI for generic single function call */
 171         alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
 172                         call_function_single_interrupt);
 173
 174         /* Low priority IPI to cleanup after moving an irq */
 175         set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
 176         set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
 177
 178         /* IPI used for rebooting/stopping */
 179         alloc_intr_gate(REBOOT_VECTOR, reboot_interrupt);
 180 #endif
 181 #endif /* CONFIG_SMP */
 182 }
 183
 184 static void __init apic_intr_init(void)
 185 {
 186         smp_intr_init();
 187
 188 #ifdef CONFIG_X86_THERMAL_VECTOR
 189         alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
 190 #endif
 191 #ifdef CONFIG_X86_MCE_THRESHOLD
 192         alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
 193 #endif
 194 #if defined(CONFIG_X86_MCE) && defined(CONFIG_X86_LOCAL_APIC)
 195         alloc_intr_gate(MCE_SELF_VECTOR, mce_self_interrupt);
 196 #endif
 197
 198 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
 199         /* self generated IPI for local APIC timer */
 200         alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
 201
 202         /* IPI for X86 platform specific use */
 203         alloc_intr_gate(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi);
 204
 205         /* IPI vectors for APIC spurious and error interrupts */
 206         alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
 207         alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
 208
 209         /* Performance monitoring interrupts: */
 210 # ifdef CONFIG_PERF_EVENTS
 211         alloc_intr_gate(LOCAL_PENDING_VECTOR, perf_pending_interrupt);
 212 # endif
 213
 214 #endif
 215 }
 216
 217 void __init native_init_IRQ(void)
 218 {
 219         int i;
 220
 221         /* Execute any quirks before the call gates are initialised: */
 222         x86_init.irqs.pre_vector_init();
 223
 224         apic_intr_init();
 225
 226         /*
 227          * Cover the whole vector space, no vector can escape
 228          * us. (some of these will be overridden and become
 229          * 'special' SMP interrupts)
 230          */
 231         for (i = FIRST_EXTERNAL_VECTOR; i < NR_VECTORS; i++) {
 232                 /* IA32_SYSCALL_VECTOR could be used in trap_init already. */
 233                 if (!test_bit(i, used_vectors))
 234                         set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);
 235         }
 236
 237         if (!acpi_ioapic)
 238                 setup_irq(2, &irq2);
 239
 240 #ifdef CONFIG_X86_32
 241         /*
 242          * External FPU? Set up irq13 if so, for
 243          * original braindamaged IBM FERR coupling.
 244          */
 245         if (boot_cpu_data.hard_math && !cpu_has_fpu)
 246                 setup_irq(FPU_IRQ, &fpu_irq);
 247
 248         irq_ctx_init(smp_processor_id());
 249 #endif
 250 }