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/random.h>
   9 #include <linux/kprobes.h>
  10 #include <linux/init.h>
  11 #include <linux/kernel_stat.h>
  12 #include <linux/sysdev.h>
  13 #include <linux/bitops.h>
  14 #include <linux/acpi.h>
  15 #include <linux/io.h>
  16 #include <linux/delay.h>
  17
  18 #include <asm/atomic.h>
  19 #include <asm/system.h>
  20 #include <asm/timer.h>
  21 #include <asm/hw_irq.h>
  22 #include <asm/pgtable.h>
  23 #include <asm/desc.h>
  24 #include <asm/apic.h>
  25 #include <asm/setup.h>
  26 #include <asm/i8259.h>
  27 #include <asm/traps.h>
  28
  29 /*
  30  * ISA PIC or low IO-APIC triggered (INTA-cycle or APIC) interrupts:
  31  * (these are usually mapped to vectors 0x30-0x3f)
  32  */
  33
  34 /*
  35  * The IO-APIC gives us many more interrupt sources. Most of these
  36  * are unused but an SMP system is supposed to have enough memory ...
  37  * sometimes (mostly wrt. hw bugs) we get corrupted vectors all
  38  * across the spectrum, so we really want to be prepared to get all
  39  * of these. Plus, more powerful systems might have more than 64
  40  * IO-APIC registers.
  41  *
  42  * (these are usually mapped into the 0x30-0xff vector range)
  43  */
  44
  45 #ifdef CONFIG_X86_32
  46 /*
  47  * Note that on a 486, we don't want to do a SIGFPE on an irq13
  48  * as the irq is unreliable, and exception 16 works correctly
  49  * (ie as explained in the intel literature). On a 386, you
  50  * can't use exception 16 due to bad IBM design, so we have to
  51  * rely on the less exact irq13.
  52  *
  53  * Careful.. Not only is IRQ13 unreliable, but it is also
  54  * leads to races. IBM designers who came up with it should
  55  * be shot.
  56  */
  57
  58 static irqreturn_t math_error_irq(int cpl, void *dev_id)
  59 {
  60         outb(0, 0xF0);
  61         if (ignore_fpu_irq || !boot_cpu_data.hard_math)
  62                 return IRQ_NONE;
  63         math_error((void __user *)get_irq_regs()->ip);
  64         return IRQ_HANDLED;
  65 }
  66
  67 /*
  68  * New motherboards sometimes make IRQ 13 be a PCI interrupt,
  69  * so allow interrupt sharing.
  70  */
  71 static struct irqaction fpu_irq = {
  72         .handler = math_error_irq,
  73         .name = "fpu",
  74 };
  75 #endif
  76
  77 /*
  78  * IRQ2 is cascade interrupt to second interrupt controller
  79  */
  80 static struct irqaction irq2 = {
  81         .handler = no_action,
  82         .name = "cascade",
  83 };
  84
  85 DEFINE_PER_CPU(vector_irq_t, vector_irq) = {
  86         [0 ... NR_VECTORS - 1] = -1,
  87 };
  88
  89 int vector_used_by_percpu_irq(unsigned int vector)
  90 {
  91         int cpu;
  92
  93         for_each_online_cpu(cpu) {
  94                 if (per_cpu(vector_irq, cpu)[vector] != -1)
  95                         return 1;
  96         }
  97
  98         return 0;
  99 }
 100
 101 void __init init_ISA_irqs(void)
 102 {
 103         int i;
 104
 105 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
 106         init_bsp_APIC();
 107 #endif
 108         legacy_pic->init(0);
 109
 110         /*
 111          * 16 old-style INTA-cycle interrupts:
 112          */
 113         for (i = 0; i < legacy_pic->nr_legacy_irqs; i++) {
 114                 struct irq_desc *desc = irq_to_desc(i);
 115
 116                 desc->status = IRQ_DISABLED;
 117                 desc->action = NULL;
 118                 desc->depth = 1;
 119
 120                 set_irq_chip_and_handler_name(i, &i8259A_chip,
 121                                               handle_level_irq, "XT");
 122         }
 123 }
 124
 125 void __init init_IRQ(void)
 126 {
 127         int i;
 128
 129         /*
 130          * On cpu 0, Assign IRQ0_VECTOR..IRQ15_VECTOR's to IRQ 0..15.
 131          * If these IRQ's are handled by legacy interrupt-controllers like PIC,
 132          * then this configuration will likely be static after the boot. If
 133          * these IRQ's are handled by more mordern controllers like IO-APIC,
 134          * then this vector space can be freed and re-used dynamically as the
 135          * irq's migrate etc.
 136          */
 137         for (i = 0; i < legacy_pic->nr_legacy_irqs; i++)
 138                 per_cpu(vector_irq, 0)[IRQ0_VECTOR + i] = i;
 139
 140         x86_init.irqs.intr_init();
 141 }
 142
 143 /*
 144  * Setup the vector to irq mappings.
 145  */
 146 void setup_vector_irq(int cpu)
 147 {
 148 #ifndef CONFIG_X86_IO_APIC
 149         int irq;
 150
 151         /*
 152          * On most of the platforms, legacy PIC delivers the interrupts on the
 153          * boot cpu. But there are certain platforms where PIC interrupts are
 154          * delivered to multiple cpu's. If the legacy IRQ is handled by the
 155          * legacy PIC, for the new cpu that is coming online, setup the static
 156          * legacy vector to irq mapping:
 157          */
 158         for (irq = 0; irq < legacy_pic->nr_legacy_irqs; irq++)
 159                 per_cpu(vector_irq, cpu)[IRQ0_VECTOR + irq] = irq;
 160 #endif
 161
 162         __setup_vector_irq(cpu);
 163 }
 164
 165 static void __init smp_intr_init(void)
 166 {
 167 #ifdef CONFIG_SMP
 168 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
 169         /*
 170          * The reschedule interrupt is a CPU-to-CPU reschedule-helper
 171          * IPI, driven by wakeup.
 172          */
 173         alloc_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt);
 174
 175         /* IPIs for invalidation */
 176         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+0, invalidate_interrupt0);
 177         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+1, invalidate_interrupt1);
 178         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+2, invalidate_interrupt2);
 179         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+3, invalidate_interrupt3);
 180         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+4, invalidate_interrupt4);
 181         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+5, invalidate_interrupt5);
 182         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+6, invalidate_interrupt6);
 183         alloc_intr_gate(INVALIDATE_TLB_VECTOR_START+7, invalidate_interrupt7);
 184
 185         /* IPI for generic function call */
 186         alloc_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
 187
 188         /* IPI for generic single function call */
 189         alloc_intr_gate(CALL_FUNCTION_SINGLE_VECTOR,
 190                         call_function_single_interrupt);
 191
 192         /* Low priority IPI to cleanup after moving an irq */
 193         set_intr_gate(IRQ_MOVE_CLEANUP_VECTOR, irq_move_cleanup_interrupt);
 194         set_bit(IRQ_MOVE_CLEANUP_VECTOR, used_vectors);
 195
 196         /* IPI used for rebooting/stopping */
 197         alloc_intr_gate(REBOOT_VECTOR, reboot_interrupt);
 198 #endif
 199 #endif /* CONFIG_SMP */
 200 }
 201
 202 static void __init apic_intr_init(void)
 203 {
 204         smp_intr_init();
 205
 206 #ifdef CONFIG_X86_THERMAL_VECTOR
 207         alloc_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
 208 #endif
 209 #ifdef CONFIG_X86_MCE_THRESHOLD
 210         alloc_intr_gate(THRESHOLD_APIC_VECTOR, threshold_interrupt);
 211 #endif
 212 #if defined(CONFIG_X86_MCE) && defined(CONFIG_X86_LOCAL_APIC)
 213         alloc_intr_gate(MCE_SELF_VECTOR, mce_self_interrupt);
 214 #endif
 215
 216 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_LOCAL_APIC)
 217         /* self generated IPI for local APIC timer */
 218         alloc_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
 219
 220         /* IPI for X86 platform specific use */
 221         alloc_intr_gate(X86_PLATFORM_IPI_VECTOR, x86_platform_ipi);
 222
 223         /* IPI vectors for APIC spurious and error interrupts */
 224         alloc_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
 225         alloc_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
 226
 227         /* Performance monitoring interrupts: */
 228 # ifdef CONFIG_PERF_EVENTS
 229         alloc_intr_gate(LOCAL_PENDING_VECTOR, perf_pending_interrupt);
 230 # endif
 231
 232 #endif
 233 }
 234
 235 void __init native_init_IRQ(void)
 236 {
 237         int i;
 238
 239         /* Execute any quirks before the call gates are initialised: */
 240         x86_init.irqs.pre_vector_init();
 241
 242         apic_intr_init();
 243
 244         /*
 245          * Cover the whole vector space, no vector can escape
 246          * us. (some of these will be overridden and become
 247          * 'special' SMP interrupts)
 248          */
 249         for (i = FIRST_EXTERNAL_VECTOR; i < NR_VECTORS; i++) {
 250                 /* IA32_SYSCALL_VECTOR could be used in trap_init already. */
 251                 if (!test_bit(i, used_vectors))
 252                         set_intr_gate(i, interrupt[i-FIRST_EXTERNAL_VECTOR]);
 253         }
 254
 255         if (!acpi_ioapic)
 256                 setup_irq(2, &irq2);
 257
 258 #ifdef CONFIG_X86_32
 259         /*
 260          * External FPU? Set up irq13 if so, for
 261          * original braindamaged IBM FERR coupling.
 262          */
 263         if (boot_cpu_data.hard_math && !cpu_has_fpu)
 264                 setup_irq(FPU_IRQ, &fpu_irq);
 265
 266         irq_ctx_init(smp_processor_id());
 267 #endif
 268 }