diff options
author | Ingo Molnar <mingo@elte.hu> | 2008-07-18 18:43:08 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2008-07-18 18:43:08 +0200 |
commit | f1b0c8d3d3b5ff9c0b14bb2383a4bc38d8922bd1 (patch) | |
tree | b7d9f439d5b99d8b03bf490d4b17156414e48d45 /arch/x86/kernel/irqinit_32.c | |
parent | d591b0a3ae25f587d0c4da1e1d1a425143590790 (diff) | |
parent | 5b664cb235e97afbf34db9c4d77f08ebd725335e (diff) |
Merge branch 'linus' into x86/amd-iommu
Diffstat (limited to 'arch/x86/kernel/irqinit_32.c')
-rw-r--r-- | arch/x86/kernel/irqinit_32.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/arch/x86/kernel/irqinit_32.c b/arch/x86/kernel/irqinit_32.c new file mode 100644 index 00000000000..d66914287ee --- /dev/null +++ b/arch/x86/kernel/irqinit_32.c @@ -0,0 +1,114 @@ +#include <linux/errno.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/ioport.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/init.h> +#include <linux/kernel_stat.h> +#include <linux/sysdev.h> +#include <linux/bitops.h> + +#include <asm/atomic.h> +#include <asm/system.h> +#include <asm/io.h> +#include <asm/timer.h> +#include <asm/pgtable.h> +#include <asm/delay.h> +#include <asm/desc.h> +#include <asm/apic.h> +#include <asm/arch_hooks.h> +#include <asm/i8259.h> + + + +/* + * Note that on a 486, we don't want to do a SIGFPE on an irq13 + * as the irq is unreliable, and exception 16 works correctly + * (ie as explained in the intel literature). On a 386, you + * can't use exception 16 due to bad IBM design, so we have to + * rely on the less exact irq13. + * + * Careful.. Not only is IRQ13 unreliable, but it is also + * leads to races. IBM designers who came up with it should + * be shot. + */ + + +static irqreturn_t math_error_irq(int cpl, void *dev_id) +{ + extern void math_error(void __user *); + outb(0,0xF0); + if (ignore_fpu_irq || !boot_cpu_data.hard_math) + return IRQ_NONE; + math_error((void __user *)get_irq_regs()->ip); + return IRQ_HANDLED; +} + +/* + * New motherboards sometimes make IRQ 13 be a PCI interrupt, + * so allow interrupt sharing. + */ +static struct irqaction fpu_irq = { + .handler = math_error_irq, + .mask = CPU_MASK_NONE, + .name = "fpu", +}; + +void __init init_ISA_irqs (void) +{ + int i; + +#ifdef CONFIG_X86_LOCAL_APIC + init_bsp_APIC(); +#endif + init_8259A(0); + + /* + * 16 old-style INTA-cycle interrupts: + */ + for (i = 0; i < 16; i++) { + set_irq_chip_and_handler_name(i, &i8259A_chip, + handle_level_irq, "XT"); + } +} + +/* Overridden in paravirt.c */ +void init_IRQ(void) __attribute__((weak, alias("native_init_IRQ"))); + +void __init native_init_IRQ(void) +{ + int i; + + /* all the set up before the call gates are initialised */ + pre_intr_init_hook(); + + /* + * Cover the whole vector space, no vector can escape + * us. (some of these will be overridden and become + * 'special' SMP interrupts) + */ + for (i = 0; i < (NR_VECTORS - FIRST_EXTERNAL_VECTOR); i++) { + int vector = FIRST_EXTERNAL_VECTOR + i; + if (i >= NR_IRQS) + break; + /* SYSCALL_VECTOR was reserved in trap_init. */ + if (!test_bit(vector, used_vectors)) + set_intr_gate(vector, interrupt[i]); + } + + /* setup after call gates are initialised (usually add in + * the architecture specific gates) + */ + intr_init_hook(); + + /* + * External FPU? Set up irq13 if so, for + * original braindamaged IBM FERR coupling. + */ + if (boot_cpu_data.hard_math && !cpu_has_fpu) + setup_irq(FPU_IRQ, &fpu_irq); + + irq_ctx_init(smp_processor_id()); +} |