diff options
Diffstat (limited to 'arch/powerpc/kernel/irq.c')
-rw-r--r-- | arch/powerpc/kernel/irq.c | 479 |
1 files changed, 479 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c new file mode 100644 index 00000000000..5a71ed9612f --- /dev/null +++ b/arch/powerpc/kernel/irq.c @@ -0,0 +1,479 @@ +/* + * arch/ppc/kernel/irq.c + * + * Derived from arch/i386/kernel/irq.c + * Copyright (C) 1992 Linus Torvalds + * Adapted from arch/i386 by Gary Thomas + * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) + * Updated and modified by Cort Dougan <cort@fsmlabs.com> + * Copyright (C) 1996-2001 Cort Dougan + * Adapted for Power Macintosh by Paul Mackerras + * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au) + * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * This file contains the code used by various IRQ handling routines: + * asking for different IRQ's should be done through these routines + * instead of just grabbing them. Thus setups with different IRQ numbers + * shouldn't result in any weird surprises, and installing new handlers + * should be easier. + * + * The MPC8xx has an interrupt mask in the SIU. If a bit is set, the + * interrupt is _enabled_. As expected, IRQ0 is bit 0 in the 32-bit + * mask register (of which only 16 are defined), hence the weird shifting + * and complement of the cached_irq_mask. I want to be able to stuff + * this right into the SIU SMASK register. + * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx + * to reduce code space and undefined function references. + */ + +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/threads.h> +#include <linux/kernel_stat.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/ptrace.h> +#include <linux/ioport.h> +#include <linux/interrupt.h> +#include <linux/timex.h> +#include <linux/config.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/pci.h> +#include <linux/delay.h> +#include <linux/irq.h> +#include <linux/proc_fs.h> +#include <linux/random.h> +#include <linux/seq_file.h> +#include <linux/cpumask.h> +#include <linux/profile.h> +#include <linux/bitops.h> +#ifdef CONFIG_PPC64 +#include <linux/kallsyms.h> +#endif + +#include <asm/uaccess.h> +#include <asm/system.h> +#include <asm/io.h> +#include <asm/pgtable.h> +#include <asm/irq.h> +#include <asm/cache.h> +#include <asm/prom.h> +#include <asm/ptrace.h> +#include <asm/machdep.h> +#ifdef CONFIG_PPC64 +#include <asm/iseries/it_lp_queue.h> +#include <asm/paca.h> +#endif + +int __irq_offset_value; +#ifdef CONFIG_PPC32 +EXPORT_SYMBOL(__irq_offset_value); +#endif + +static int ppc_spurious_interrupts; + +#if defined(CONFIG_PPC_ISERIES) && defined(CONFIG_SMP) +extern void iSeries_smp_message_recv(struct pt_regs *); +#endif + +#ifdef CONFIG_PPC32 +#define NR_MASK_WORDS ((NR_IRQS + 31) / 32) + +unsigned long ppc_cached_irq_mask[NR_MASK_WORDS]; +atomic_t ppc_n_lost_interrupts; + +#ifdef CONFIG_TAU_INT +extern int tau_initialized; +extern int tau_interrupts(int); +#endif + +#if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE) +extern atomic_t ipi_recv; +extern atomic_t ipi_sent; +#endif +#endif /* CONFIG_PPC32 */ + +#ifdef CONFIG_PPC64 +EXPORT_SYMBOL(irq_desc); + +int distribute_irqs = 1; +u64 ppc64_interrupt_controller; +#endif /* CONFIG_PPC64 */ + +int show_interrupts(struct seq_file *p, void *v) +{ + int i = *(loff_t *)v, j; + struct irqaction *action; + irq_desc_t *desc; + unsigned long flags; + + if (i == 0) { + seq_puts(p, " "); + for_each_online_cpu(j) + seq_printf(p, "CPU%d ", j); + seq_putc(p, '\n'); + } + + if (i < NR_IRQS) { + desc = get_irq_desc(i); + spin_lock_irqsave(&desc->lock, flags); + action = desc->action; + if (!action || !action->handler) + goto skip; + seq_printf(p, "%3d: ", i); +#ifdef CONFIG_SMP + for_each_online_cpu(j) + seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]); +#else + seq_printf(p, "%10u ", kstat_irqs(i)); +#endif /* CONFIG_SMP */ + if (desc->handler) + seq_printf(p, " %s ", desc->handler->typename); + else + seq_puts(p, " None "); + seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge "); + seq_printf(p, " %s", action->name); + for (action = action->next; action; action = action->next) + seq_printf(p, ", %s", action->name); + seq_putc(p, '\n'); +skip: + spin_unlock_irqrestore(&desc->lock, flags); + } else if (i == NR_IRQS) { +#ifdef CONFIG_PPC32 +#ifdef CONFIG_TAU_INT + if (tau_initialized){ + seq_puts(p, "TAU: "); + for (j = 0; j < NR_CPUS; j++) + if (cpu_online(j)) + seq_printf(p, "%10u ", tau_interrupts(j)); + seq_puts(p, " PowerPC Thermal Assist (cpu temp)\n"); + } +#endif +#if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE) + /* should this be per processor send/receive? */ + seq_printf(p, "IPI (recv/sent): %10u/%u\n", + atomic_read(&ipi_recv), atomic_read(&ipi_sent)); +#endif +#endif /* CONFIG_PPC32 */ + seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts); + } + return 0; +} + +#ifdef CONFIG_HOTPLUG_CPU +void fixup_irqs(cpumask_t map) +{ + unsigned int irq; + static int warned; + + for_each_irq(irq) { + cpumask_t mask; + + if (irq_desc[irq].status & IRQ_PER_CPU) + continue; + + cpus_and(mask, irq_affinity[irq], map); + if (any_online_cpu(mask) == NR_CPUS) { + printk("Breaking affinity for irq %i\n", irq); + mask = map; + } + if (irq_desc[irq].handler->set_affinity) + irq_desc[irq].handler->set_affinity(irq, mask); + else if (irq_desc[irq].action && !(warned++)) + printk("Cannot set affinity for irq %i\n", irq); + } + + local_irq_enable(); + mdelay(1); + local_irq_disable(); +} +#endif + +#ifdef CONFIG_PPC_ISERIES +void do_IRQ(struct pt_regs *regs) +{ + struct paca_struct *lpaca; + + irq_enter(); + +#ifdef CONFIG_DEBUG_STACKOVERFLOW + /* Debugging check for stack overflow: is there less than 2KB free? */ + { + long sp; + + sp = __get_SP() & (THREAD_SIZE-1); + + if (unlikely(sp < (sizeof(struct thread_info) + 2048))) { + printk("do_IRQ: stack overflow: %ld\n", + sp - sizeof(struct thread_info)); + dump_stack(); + } + } +#endif + + lpaca = get_paca(); +#ifdef CONFIG_SMP + if (lpaca->lppaca.int_dword.fields.ipi_cnt) { + lpaca->lppaca.int_dword.fields.ipi_cnt = 0; + iSeries_smp_message_recv(regs); + } +#endif /* CONFIG_SMP */ + if (hvlpevent_is_pending()) + process_hvlpevents(regs); + + irq_exit(); + + if (lpaca->lppaca.int_dword.fields.decr_int) { + lpaca->lppaca.int_dword.fields.decr_int = 0; + /* Signal a fake decrementer interrupt */ + timer_interrupt(regs); + } +} + +#else /* CONFIG_PPC_ISERIES */ + +void do_IRQ(struct pt_regs *regs) +{ + int irq; +#ifdef CONFIG_IRQSTACKS + struct thread_info *curtp, *irqtp; +#endif + + irq_enter(); + +#ifdef CONFIG_DEBUG_STACKOVERFLOW + /* Debugging check for stack overflow: is there less than 2KB free? */ + { + long sp; + + sp = __get_SP() & (THREAD_SIZE-1); + + if (unlikely(sp < (sizeof(struct thread_info) + 2048))) { + printk("do_IRQ: stack overflow: %ld\n", + sp - sizeof(struct thread_info)); + dump_stack(); + } + } +#endif + + /* + * Every platform is required to implement ppc_md.get_irq. + * This function will either return an irq number or -1 to + * indicate there are no more pending. + * The value -2 is for buggy hardware and means that this IRQ + * has already been handled. -- Tom + */ + irq = ppc_md.get_irq(regs); + + if (irq >= 0) { +#ifdef CONFIG_IRQSTACKS + /* Switch to the irq stack to handle this */ + curtp = current_thread_info(); + irqtp = hardirq_ctx[smp_processor_id()]; + if (curtp != irqtp) { + irqtp->task = curtp->task; + irqtp->flags = 0; + call___do_IRQ(irq, regs, irqtp); + irqtp->task = NULL; + if (irqtp->flags) + set_bits(irqtp->flags, &curtp->flags); + } else +#endif + __do_IRQ(irq, regs); + } else +#ifdef CONFIG_PPC32 + if (irq != -2) +#endif + /* That's not SMP safe ... but who cares ? */ + ppc_spurious_interrupts++; + irq_exit(); +} + +#endif /* CONFIG_PPC_ISERIES */ + +void __init init_IRQ(void) +{ +#ifdef CONFIG_PPC64 + static int once = 0; + + if (once) + return; + + once++; + +#endif + ppc_md.init_IRQ(); +#ifdef CONFIG_PPC64 + irq_ctx_init(); +#endif +} + +#ifdef CONFIG_PPC64 +/* + * Virtual IRQ mapping code, used on systems with XICS interrupt controllers. + */ + +#define UNDEFINED_IRQ 0xffffffff +unsigned int virt_irq_to_real_map[NR_IRQS]; + +/* + * Don't use virtual irqs 0, 1, 2 for devices. + * The pcnet32 driver considers interrupt numbers < 2 to be invalid, + * and 2 is the XICS IPI interrupt. + * We limit virtual irqs to 17 less than NR_IRQS so that when we + * offset them by 16 (to reserve the first 16 for ISA interrupts) + * we don't end up with an interrupt number >= NR_IRQS. + */ +#define MIN_VIRT_IRQ 3 +#define MAX_VIRT_IRQ (NR_IRQS - NUM_ISA_INTERRUPTS - 1) +#define NR_VIRT_IRQS (MAX_VIRT_IRQ - MIN_VIRT_IRQ + 1) + +void +virt_irq_init(void) +{ + int i; + for (i = 0; i < NR_IRQS; i++) + virt_irq_to_real_map[i] = UNDEFINED_IRQ; +} + +/* Create a mapping for a real_irq if it doesn't already exist. + * Return the virtual irq as a convenience. + */ +int virt_irq_create_mapping(unsigned int real_irq) +{ + unsigned int virq, first_virq; + static int warned; + + if (ppc64_interrupt_controller == IC_OPEN_PIC) + return real_irq; /* no mapping for openpic (for now) */ + + if (ppc64_interrupt_controller == IC_CELL_PIC) + return real_irq; /* no mapping for iic either */ + + /* don't map interrupts < MIN_VIRT_IRQ */ + if (real_irq < MIN_VIRT_IRQ) { + virt_irq_to_real_map[real_irq] = real_irq; + return real_irq; + } + + /* map to a number between MIN_VIRT_IRQ and MAX_VIRT_IRQ */ + virq = real_irq; + if (virq > MAX_VIRT_IRQ) + virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ; + + /* search for this number or a free slot */ + first_virq = virq; + while (virt_irq_to_real_map[virq] != UNDEFINED_IRQ) { + if (virt_irq_to_real_map[virq] == real_irq) + return virq; + if (++virq > MAX_VIRT_IRQ) + virq = MIN_VIRT_IRQ; + if (virq == first_virq) + goto nospace; /* oops, no free slots */ + } + + virt_irq_to_real_map[virq] = real_irq; + return virq; + + nospace: + if (!warned) { + printk(KERN_CRIT "Interrupt table is full\n"); + printk(KERN_CRIT "Increase NR_IRQS (currently %d) " + "in your kernel sources and rebuild.\n", NR_IRQS); + warned = 1; + } + return NO_IRQ; +} + +/* + * In most cases will get a hit on the very first slot checked in the + * virt_irq_to_real_map. Only when there are a large number of + * IRQs will this be expensive. + */ +unsigned int real_irq_to_virt_slowpath(unsigned int real_irq) +{ + unsigned int virq; + unsigned int first_virq; + + virq = real_irq; + + if (virq > MAX_VIRT_IRQ) + virq = (virq % NR_VIRT_IRQS) + MIN_VIRT_IRQ; + + first_virq = virq; + + do { + if (virt_irq_to_real_map[virq] == real_irq) + return virq; + + virq++; + + if (virq >= MAX_VIRT_IRQ) + virq = 0; + + } while (first_virq != virq); + + return NO_IRQ; + +} + +#ifdef CONFIG_IRQSTACKS +struct thread_info *softirq_ctx[NR_CPUS]; +struct thread_info *hardirq_ctx[NR_CPUS]; + +void irq_ctx_init(void) +{ + struct thread_info *tp; + int i; + + for_each_cpu(i) { + memset((void *)softirq_ctx[i], 0, THREAD_SIZE); + tp = softirq_ctx[i]; + tp->cpu = i; + tp->preempt_count = SOFTIRQ_OFFSET; + + memset((void *)hardirq_ctx[i], 0, THREAD_SIZE); + tp = hardirq_ctx[i]; + tp->cpu = i; + tp->preempt_count = HARDIRQ_OFFSET; + } +} + +void do_softirq(void) +{ + unsigned long flags; + struct thread_info *curtp, *irqtp; + + if (in_interrupt()) + return; + + local_irq_save(flags); + + if (local_softirq_pending()) { + curtp = current_thread_info(); + irqtp = softirq_ctx[smp_processor_id()]; + irqtp->task = curtp->task; + call_do_softirq(irqtp); + irqtp->task = NULL; + } + + local_irq_restore(flags); +} +EXPORT_SYMBOL(do_softirq); + +#endif /* CONFIG_IRQSTACKS */ + +static int __init setup_noirqdistrib(char *str) +{ + distribute_irqs = 0; + return 1; +} + +__setup("noirqdistrib", setup_noirqdistrib); +#endif /* CONFIG_PPC64 */ |