/* $Id: irq.c,v 1.113 2001/07/17 16:17:33 anton Exp $ * arch/sparc/kernel/irq.c: Interrupt request handling routines. On the * Sparc the IRQ's are basically 'cast in stone' * and you are supposed to probe the prom's device * node trees to find out who's got which IRQ. * * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) * Copyright (C) 1995 Miguel de Icaza (miguel@nuclecu.unam.mx) * Copyright (C) 1995 Pete A. Zaitcev (zaitcev@yahoo.com) * Copyright (C) 1996 Dave Redman (djhr@tadpole.co.uk) * Copyright (C) 1998-2000 Anton Blanchard (anton@samba.org) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Dave Redman (djhr@tadpole.co.uk) * * IRQ numbers.. These are no longer restricted to 15.. * * this is done to enable SBUS cards and onboard IO to be masked * correctly. using the interrupt level isn't good enough. * * For example: * A device interrupting at sbus level6 and the Floppy both come in * at IRQ11, but enabling and disabling them requires writing to * different bits in the SLAVIO/SEC. * * As a result of these changes sun4m machines could now support * directed CPU interrupts using the existing enable/disable irq code * with tweaks. * */ static void irq_panic(void) { extern char *cputypval; prom_printf("machine: %s doesn't have irq handlers defined!\n",cputypval); prom_halt(); } void (*init_timers)(void (*)(int, void *,struct pt_regs *)) = (void (*)(void (*)(int, void *,struct pt_regs *))) irq_panic; /* * Dave Redman (djhr@tadpole.co.uk) * * There used to be extern calls and hard coded values here.. very sucky! * instead, because some of the devices attach very early, I do something * equally sucky but at least we'll never try to free statically allocated * space or call kmalloc before kmalloc_init :(. * * In fact it's the timer10 that attaches first.. then timer14 * then kmalloc_init is called.. then the tty interrupts attach. * hmmm.... * */ #define MAX_STATIC_ALLOC 4 struct irqaction static_irqaction[MAX_STATIC_ALLOC]; int static_irq_count = 0; struct irqaction *irq_action[NR_IRQS+1] = { NULL, NULL, NULL, NULL, NULL, NULL , NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL , NULL, NULL }; int get_irq_list(char *buf) { int i, len = 0; struct irqaction * action; #ifdef CONFIG_SMP int j; #endif if (sparc_cpu_model == sun4d) { extern int sun4d_get_irq_list(char *); return sun4d_get_irq_list(buf); } for (i = 0 ; i < (NR_IRQS+1) ; i++) { action = *(i + irq_action); if (!action) continue; len += sprintf(buf+len, "%3d: ", i); #ifndef CONFIG_SMP len += sprintf(buf+len, "%10u ", kstat_irqs(i)); #else for (j = 0; j < smp_num_cpus; j++) len += sprintf(buf+len, "%10u ", kstat.irqs[cpu_logical_map(j)][i]); #endif len += sprintf(buf+len, " %c %s", (action->flags & SA_INTERRUPT) ? '+' : ' ', action->name); for (action=action->next; action; action = action->next) { len += sprintf(buf+len, ",%s %s", (action->flags & SA_INTERRUPT) ? " +" : "", action->name); } len += sprintf(buf+len, "\n"); } return len; } void free_irq(unsigned int irq, void *dev_id) { struct irqaction * action; struct irqaction * tmp = NULL; unsigned long flags; unsigned int cpu_irq; if (sparc_cpu_model == sun4d) { extern void sun4d_free_irq(unsigned int, void *); return sun4d_free_irq(irq, dev_id); } cpu_irq = irq & NR_IRQS; action = *(cpu_irq + irq_action); if (cpu_irq > 14) { /* 14 irq levels on the sparc */ printk("Trying to free bogus IRQ %d\n", irq); return; } if (!action->handler) { printk("Trying to free free IRQ%d\n",irq); return; } if (dev_id) { for (; action; action = action->next) { if (action->dev_id == dev_id) break; tmp = action; } if (!action) { printk("Trying to free free shared IRQ%d\n",irq); return; } } else if (action->flags & SA_SHIRQ) { printk("Trying to free shared IRQ%d with NULL device ID\n", irq); return; } if (action->flags & SA_STATIC_ALLOC) { /* This interrupt is marked as specially allocated * so it is a bad idea to free it. */ printk("Attempt to free statically allocated IRQ%d (%s)\n", irq, action->name); return; } save_and_cli(flags); if (action && tmp) tmp->next = action->next; else *(cpu_irq + irq_action) = action->next; kfree(action); if (!(*(cpu_irq + irq_action))) disable_irq(irq); restore_flags(flags); } #ifdef CONFIG_SMP /* Who has the global irq brlock */ unsigned char global_irq_holder = NO_PROC_ID; void smp_show_backtrace_all_cpus(void); void show_backtrace(void); #define VERBOSE_DEBUG_IRQLOCK #define MAXCOUNT 100000000 static void show(char * str) { int cpu = smp_processor_id(); int i; printk("\n%s, CPU %d:\n", str, cpu); printk("irq: %d [ ", irqs_running()); for (i = 0; i < smp_num_cpus; i++) printk("%u ", __brlock_array[i][BR_GLOBALIRQ_LOCK]); printk("]\nbh: %d [ ", (spin_is_locked(&global_bh_lock) ? 1 : 0)); for (i = 0; i < smp_num_cpus; i++) printk("%u ", local_bh_count(i)); printk("]\n"); #ifdef VERBOSE_DEBUG_IRQLOCK smp_show_backtrace_all_cpus(); #else show_backtrace(); #endif } /* * We have to allow irqs to arrive between __sti and __cli */ #define SYNC_OTHER_CORES(x) barrier() /* * This is called when we want to synchronize with * interrupts. We may for example tell a device to * stop sending interrupts: but to make sure there * are no interrupts that are executing on another * CPU we need to call this function. */ void synchronize_irq(void) { if (irqs_running()) { cli(); sti(); } } static inline void get_irqlock(int cpu) { int count; if ((unsigned char)cpu == global_irq_holder) return; count = MAXCOUNT; again: br_write_lock(BR_GLOBALIRQ_LOCK); for (;;) { spinlock_t *lock; if (!irqs_running() && (local_bh_count(smp_processor_id()) || !spin_is_locked(&global_bh_lock))) break; br_write_unlock(BR_GLOBALIRQ_LOCK); lock = &__br_write_locks[BR_GLOBALIRQ_LOCK].lock; while (irqs_running() || spin_is_locked(lock) || (!local_bh_count(smp_processor_id()) && spin_is_locked(&global_bh_lock))) { if (!--count) { show("get_irqlock"); count = (~0 >> 1); } __sti(); SYNC_OTHER_CORES(cpu); __cli(); } goto again; } global_irq_holder = cpu; } /* * A global "cli()" while in an interrupt context * turns into just a local cli(). Interrupts * should use spinlocks for the (very unlikely) * case that they ever want to protect against * each other. * * If we already have local interrupts disabled, * this will not turn a local disable into a * global one (problems with spinlocks: this makes * save_flags+cli+sti usable inside a spinlock). */ void __global_cli(void) { unsigned long flags; __save_flags(flags); if ((flags & PSR_PIL) != PSR_PIL) { int cpu = smp_processor_id(); __cli(); if (!local_irq_count(cpu)) get_irqlock(cpu); } } void __global_sti(void) { int cpu = smp_processor_id(); if (!local_irq_count(cpu)) release_irqlock(cpu); __sti(); } /* * SMP flags value to restore to: * 0 - global cli * 1 - global sti * 2 - local cli * 3 - local sti */ unsigned long __global_save_flags(void) { unsigned long flags, retval; unsigned long local_enabled = 0; __save_flags(flags); if ((flags & PSR_PIL) != PSR_PIL) local_enabled = 1; /* default to local */ retval = 2 + local_enabled; /* check for global flags if we're not in an interrupt */ if (!local_irq_count(smp_processor_id())) { if (local_enabled) retval = 1; if (global_irq_holder == (unsigned char) smp_processor_id()) retval = 0; } return retval; } void __global_restore_flags(unsigned long flags) { switch (flags) { case 0: __global_cli(); break; case 1: __global_sti(); break; case 2: __cli(); break; case 3: __sti(); break; default: { unsigned long pc; __asm__ __volatile__("mov %%i7, %0" : "=r" (pc)); printk("global_restore_flags: Bogon flags(%08lx) caller %08lx\n", flags, pc); } } } #endif /* CONFIG_SMP */ void unexpected_irq(int irq, void *dev_id, struct pt_regs * regs) { int i; struct irqaction * action; unsigned int cpu_irq; cpu_irq = irq & NR_IRQS; action = *(cpu_irq + irq_action); printk("IO device interrupt, irq = %d\n", irq); printk("PC = %08lx NPC = %08lx FP=%08lx\n", regs->pc, regs->npc, regs->u_regs[14]); if (action) { printk("Expecting: "); for (i = 0; i < 16; i++) if (action->handler) prom_printf("[%s:%d:0x%x] ", action->name, (int) i, (unsigned int) action->handler); } printk("AIEEE\n"); panic("bogus interrupt received"); } void handler_irq(int irq, struct pt_regs * regs) { struct irqaction * action; int cpu = smp_processor_id(); #ifdef CONFIG_SMP extern void smp4m_irq_rotate(int cpu); #endif irq_enter(cpu, irq); disable_pil_irq(irq); #ifdef CONFIG_SMP /* Only rotate on lower priority IRQ's (scsi, ethernet, etc.). */ if(irq < 10) smp4m_irq_rotate(cpu); #endif action = *(irq + irq_action); kstat.irqs[cpu][irq]++; do { if (!action || !action->handler) unexpected_irq(irq, 0, regs); action->handler(irq, action->dev_id, regs); action = action->next; } while (action); enable_pil_irq(irq); irq_exit(cpu, irq); if (softirq_pending(cpu)) do_softirq(); } #ifdef CONFIG_BLK_DEV_FD extern void floppy_interrupt(int irq, void *dev_id, struct pt_regs *regs); void sparc_floppy_irq(int irq, void *dev_id, struct pt_regs *regs) { int cpu = smp_processor_id(); disable_pil_irq(irq); irq_enter(cpu, irq); kstat.irqs[cpu][irq]++; floppy_interrupt(irq, dev_id, regs); irq_exit(cpu, irq); enable_pil_irq(irq); if (softirq_pending(cpu)) do_softirq(); } #endif /* Fast IRQ's on the Sparc can only have one routine attached to them, * thus no sharing possible. */ int request_fast_irq(unsigned int irq, void (*handler)(int, void *, struct pt_regs *), unsigned long irqflags, const char *devname) { struct irqaction *action; unsigned long flags; unsigned int cpu_irq; #ifdef CONFIG_SMP struct tt_entry *trap_table; extern struct tt_entry trapbase_cpu1, trapbase_cpu2, trapbase_cpu3; #endif cpu_irq = irq & NR_IRQS; if(cpu_irq > 14) return -EINVAL; if(!handler) return -EINVAL; action = *(cpu_irq + irq_action); if(action) { if(action->flags & SA_SHIRQ) panic("Trying to register fast irq when already shared.\n"); if(irqflags & SA_SHIRQ) panic("Trying to register fast irq as shared.\n"); /* Anyway, someone already owns it so cannot be made fast. */ printk("request_fast_irq: Trying to register yet already owned.\n"); return -EBUSY; } save_and_cli(flags); /* If this is flagged as statically allocated then we use our * private struct which is never freed. */ if (irqflags & SA_STATIC_ALLOC) { if (static_irq_count < MAX_STATIC_ALLOC) action = &static_irqaction[static_irq_count++]; else printk("Fast IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n", irq, devname); } if (action == NULL) action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL); if (!action) { restore_flags(flags); return -ENOMEM; } /* Dork with trap table if we get this far. */ #define INSTANTIATE(table) \ table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_one = SPARC_RD_PSR_L0; \ table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two = \ SPARC_BRANCH((unsigned long) handler, \ (unsigned long) &table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_two);\ table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_three = SPARC_RD_WIM_L3; \ table[SP_TRAP_IRQ1+(cpu_irq-1)].inst_four = SPARC_NOP; INSTANTIATE(sparc_ttable) #ifdef CONFIG_SMP trap_table = &trapbase_cpu1; INSTANTIATE(trap_table) trap_table = &trapbase_cpu2; INSTANTIATE(trap_table) trap_table = &trapbase_cpu3; INSTANTIATE(trap_table) #endif #undef INSTANTIATE /* * XXX Correct thing whould be to flush only I- and D-cache lines * which contain the handler in question. But as of time of the * writing we have no CPU-neutral interface to fine-grained flushes. */ flush_cache_all(); action->handler = handler; action->flags = irqflags; action->mask = 0; action->name = devname; action->dev_id = NULL; action->next = NULL; *(cpu_irq + irq_action) = action; enable_irq(irq); restore_flags(flags); return 0; } int request_irq(unsigned int irq, void (*handler)(int, void *, struct pt_regs *), unsigned long irqflags, const char * devname, void *dev_id) { struct irqaction * action, *tmp = NULL; unsigned long flags; unsigned int cpu_irq; if (sparc_cpu_model == sun4d) { extern int sun4d_request_irq(unsigned int, void (*)(int, void *, struct pt_regs *), unsigned long, const char *, void *); return sun4d_request_irq(irq, handler, irqflags, devname, dev_id); } cpu_irq = irq & NR_IRQS; if(cpu_irq > 14) return -EINVAL; if (!handler) return -EINVAL; action = *(cpu_irq + irq_action); if (action) { if ((action->flags & SA_SHIRQ) && (irqflags & SA_SHIRQ)) { for (tmp = action; tmp->next; tmp = tmp->next); } else { return -EBUSY; } if ((action->flags & SA_INTERRUPT) ^ (irqflags & SA_INTERRUPT)) { printk("Attempt to mix fast and slow interrupts on IRQ%d denied\n", irq); return -EBUSY; } action = NULL; /* Or else! */ } save_and_cli(flags); /* If this is flagged as statically allocated then we use our * private struct which is never freed. */ if (irqflags & SA_STATIC_ALLOC) { if (static_irq_count < MAX_STATIC_ALLOC) action = &static_irqaction[static_irq_count++]; else printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n",irq, devname); } if (action == NULL) action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL); if (!action) { restore_flags(flags); return -ENOMEM; } action->handler = handler; action->flags = irqflags; action->mask = 0; action->name = devname; action->next = NULL; action->dev_id = dev_id; if (tmp) tmp->next = action; else *(cpu_irq + irq_action) = action; enable_irq(irq); restore_flags(flags); return 0; } /* We really don't need these at all on the Sparc. We only have * stubs here because they are exported to modules. */ unsigned long probe_irq_on(void) { return 0; } int probe_irq_off(unsigned long mask) { return 0; } /* djhr * This could probably be made indirect too and assigned in the CPU * bits of the code. That would be much nicer I think and would also * fit in with the idea of being able to tune your kernel for your machine * by removing unrequired machine and device support. * */ void __init init_IRQ(void) { extern void sun4c_init_IRQ( void ); extern void sun4m_init_IRQ( void ); extern void sun4d_init_IRQ( void ); switch(sparc_cpu_model) { case sun4c: case sun4: sun4c_init_IRQ(); break; case sun4m: #ifdef CONFIG_PCI pcic_probe(); if (pcic_present()) { sun4m_pci_init_IRQ(); break; } #endif sun4m_init_IRQ(); break; case sun4d: sun4d_init_IRQ(); break; default: prom_printf("Cannot initialize IRQ's on this Sun machine..."); break; } btfixup(); } void init_irq_proc(void) { /* For now, nothing... */ }