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Diffstat (limited to 'old/xenolinux-2.4.16-sparse/arch/xeno/kernel/irq.c')
| -rw-r--r-- | old/xenolinux-2.4.16-sparse/arch/xeno/kernel/irq.c | 1129 |
1 files changed, 0 insertions, 1129 deletions
diff --git a/old/xenolinux-2.4.16-sparse/arch/xeno/kernel/irq.c b/old/xenolinux-2.4.16-sparse/arch/xeno/kernel/irq.c deleted file mode 100644 index 7c855904ae..0000000000 --- a/old/xenolinux-2.4.16-sparse/arch/xeno/kernel/irq.c +++ /dev/null @@ -1,1129 +0,0 @@ -/* - * linux/arch/i386/kernel/irq.c - * - * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar - * - * 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. - */ - -/* - * (mostly architecture independent, will move to kernel/irq.c in 2.5.) - * - * IRQs are in fact implemented a bit like signal handlers for the kernel. - * Naturally it's not a 1:1 relation, but there are similarities. - */ - -#include <linux/config.h> -#include <linux/ptrace.h> -#include <linux/errno.h> -#include <linux/signal.h> -#include <linux/sched.h> -#include <linux/ioport.h> -#include <linux/interrupt.h> -#include <linux/timex.h> -#include <linux/slab.h> -#include <linux/random.h> -#include <linux/smp_lock.h> -#include <linux/init.h> -#include <linux/kernel_stat.h> -#include <linux/irq.h> -#include <linux/proc_fs.h> -#include <linux/kdb.h> - -#include <asm/atomic.h> -#include <asm/io.h> -#include <asm/smp.h> -#include <asm/system.h> -#include <asm/bitops.h> -#include <asm/uaccess.h> -#include <asm/pgalloc.h> -#include <asm/delay.h> -#include <asm/desc.h> -#include <asm/irq.h> - - - -/* - * Linux has a controller-independent x86 interrupt architecture. - * every controller has a 'controller-template', that is used - * by the main code to do the right thing. Each driver-visible - * interrupt source is transparently wired to the apropriate - * controller. Thus drivers need not be aware of the - * interrupt-controller. - * - * Various interrupt controllers we handle: 8259 PIC, SMP IO-APIC, - * PIIX4's internal 8259 PIC and SGI's Visual Workstation Cobalt (IO-)APIC. - * (IO-APICs assumed to be messaging to Pentium local-APICs) - * - * the code is designed to be easily extended with new/different - * interrupt controllers, without having to do assembly magic. - */ - -/* - * Controller mappings for all interrupt sources: - */ -irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = - { [0 ... NR_IRQS-1] = { 0, &no_irq_type, NULL, 0, SPIN_LOCK_UNLOCKED}}; - -static void register_irq_proc (unsigned int irq); - -/* - * Special irq handlers. - */ - -void no_action(int cpl, void *dev_id, struct pt_regs *regs) { } - -/* - * Generic no controller code - */ - -static void enable_none(unsigned int irq) { } -static unsigned int startup_none(unsigned int irq) { return 0; } -static void disable_none(unsigned int irq) { } -static void ack_none(unsigned int irq) -{ - printk("unexpected IRQ trap at vector %02x\n", irq); -} - -/* startup is the same as "enable", shutdown is same as "disable" */ -#define shutdown_none disable_none -#define end_none enable_none - -struct hw_interrupt_type no_irq_type = { - "none", - startup_none, - shutdown_none, - enable_none, - disable_none, - ack_none, - end_none -}; - -atomic_t irq_err_count; -#ifdef CONFIG_X86_IO_APIC -#ifdef APIC_MISMATCH_DEBUG -atomic_t irq_mis_count; -#endif -#endif - -/* - * Generic, controller-independent functions: - */ - -int get_irq_list(char *buf) -{ - int i, j; - struct irqaction * action; - char *p = buf; - - p += sprintf(p, " "); - for (j=0; j<smp_num_cpus; j++) - p += sprintf(p, "CPU%d ",j); - *p++ = '\n'; - - for (i = 0 ; i < NR_IRQS ; i++) { - action = irq_desc[i].action; - if (!action) - continue; - p += sprintf(p, "%3d: ",i); -#ifndef CONFIG_SMP - p += sprintf(p, "%10u ", kstat_irqs(i)); -#else - for (j = 0; j < smp_num_cpus; j++) - p += sprintf(p, "%10u ", - kstat.irqs[cpu_logical_map(j)][i]); -#endif - p += sprintf(p, " %14s", irq_desc[i].handler->typename); - p += sprintf(p, " %s", action->name); - - for (action=action->next; action; action = action->next) - p += sprintf(p, ", %s", action->name); - *p++ = '\n'; - } - p += sprintf(p, "NMI: "); - for (j = 0; j < smp_num_cpus; j++) - p += sprintf(p, "%10u ", - nmi_count(cpu_logical_map(j))); - p += sprintf(p, "\n"); -#if CONFIG_X86_LOCAL_APIC - p += sprintf(p, "LOC: "); - for (j = 0; j < smp_num_cpus; j++) - p += sprintf(p, "%10u ", - apic_timer_irqs[cpu_logical_map(j)]); - p += sprintf(p, "\n"); -#endif - p += sprintf(p, "ERR: %10u\n", atomic_read(&irq_err_count)); -#ifdef CONFIG_X86_IO_APIC -#ifdef APIC_MISMATCH_DEBUG - p += sprintf(p, "MIS: %10u\n", atomic_read(&irq_mis_count)); -#endif -#endif - return p - buf; -} - - -/* - * Global interrupt locks for SMP. Allow interrupts to come in on any - * CPU, yet make cli/sti act globally to protect critical regions.. - */ - -#ifdef CONFIG_SMP -unsigned char global_irq_holder = NO_PROC_ID; -unsigned volatile long global_irq_lock; /* pendantic: long for set_bit --RR */ - -extern void show_stack(unsigned long* esp); - -static void show(char * str) -{ - int i; - int cpu = smp_processor_id(); - - printk("\n%s, CPU %d:\n", str, cpu); - printk("irq: %d [",irqs_running()); - for(i=0;i < smp_num_cpus;i++) - printk(" %d",local_irq_count(i)); - printk(" ]\nbh: %d [",spin_is_locked(&global_bh_lock) ? 1 : 0); - for(i=0;i < smp_num_cpus;i++) - printk(" %d",local_bh_count(i)); - - printk(" ]\nStack dumps:"); - for(i = 0; i < smp_num_cpus; i++) { - unsigned long esp; - if (i == cpu) - continue; - printk("\nCPU %d:",i); - esp = init_tss[i].esp0; - if (!esp) { - /* tss->esp0 is set to NULL in cpu_init(), - * it's initialized when the cpu returns to user - * space. -- manfreds - */ - printk(" <unknown> "); - continue; - } - esp &= ~(THREAD_SIZE-1); - esp += sizeof(struct task_struct); - show_stack((void*)esp); - } - printk("\nCPU %d:",cpu); - show_stack(NULL); - printk("\n"); -} - -#define MAXCOUNT 100000000 - -/* - * I had a lockup scenario where a tight loop doing - * spin_unlock()/spin_lock() on CPU#1 was racing with - * spin_lock() on CPU#0. CPU#0 should have noticed spin_unlock(), but - * apparently the spin_unlock() information did not make it - * through to CPU#0 ... nasty, is this by design, do we have to limit - * 'memory update oscillation frequency' artificially like here? - * - * Such 'high frequency update' races can be avoided by careful design, but - * some of our major constructs like spinlocks use similar techniques, - * it would be nice to clarify this issue. Set this define to 0 if you - * want to check whether your system freezes. I suspect the delay done - * by SYNC_OTHER_CORES() is in correlation with 'snooping latency', but - * i thought that such things are guaranteed by design, since we use - * the 'LOCK' prefix. - */ -#define SUSPECTED_CPU_OR_CHIPSET_BUG_WORKAROUND 0 - -#if SUSPECTED_CPU_OR_CHIPSET_BUG_WORKAROUND -# define SYNC_OTHER_CORES(x) udelay(x+1) -#else -/* - * We have to allow irqs to arrive between __sti and __cli - */ -# define SYNC_OTHER_CORES(x) __asm__ __volatile__ ("nop") -#endif - -static inline void wait_on_irq(int cpu) -{ - int count = MAXCOUNT; - - for (;;) { - - /* - * Wait until all interrupts are gone. Wait - * for bottom half handlers unless we're - * already executing in one.. - */ - if (!irqs_running()) - if (local_bh_count(cpu) || !spin_is_locked(&global_bh_lock)) - break; - - /* Duh, we have to loop. Release the lock to avoid deadlocks */ - clear_bit(0,&global_irq_lock); - - for (;;) { - if (!--count) { - show("wait_on_irq"); - count = ~0; - } - __sti(); - SYNC_OTHER_CORES(cpu); - __cli(); - if (irqs_running()) - continue; - if (global_irq_lock) - continue; - if (!local_bh_count(cpu) && spin_is_locked(&global_bh_lock)) - continue; - if (!test_and_set_bit(0,&global_irq_lock)) - break; - } - } -} - -/* - * 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()) { - /* Stupid approach */ - cli(); - sti(); - } -} - -static inline void get_irqlock(int cpu) -{ -#ifdef CONFIG_KDB - static int kdb_rate; - if (KDB_IS_RUNNING() && kdb_rate++ < 10) - kdb_printf("Warning: get_irqlock on cpu %d while kdb is running, may hang\n", smp_processor_id()); -#endif /* CONFIG_KDB */ - if (test_and_set_bit(0,&global_irq_lock)) { - /* do we already hold the lock? */ - if ((unsigned char) cpu == global_irq_holder) - return; - /* Uhhuh.. Somebody else got it. Wait.. */ - do { - do { - rep_nop(); - } while (test_bit(0,&global_irq_lock)); - } while (test_and_set_bit(0,&global_irq_lock)); - } - /* - * We also to make sure that nobody else is running - * in an interrupt context. - */ - wait_on_irq(cpu); - - /* - * Ok, finally.. - */ - global_irq_holder = cpu; -} - -void __global_cli(void) -{ - panic("__global_cli"); -} - -void __global_sti(void) -{ - panic("__global_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) -{ - panic("__global_save_flags"); -} - -void __global_restore_flags(unsigned long flags) -{ - panic("__global_restore_flags"); -} - -#endif - -/* - * This should really return information about whether - * we should do bottom half handling etc. Right now we - * end up _always_ checking the bottom half, which is a - * waste of time and is not what some drivers would - * prefer. - */ -int handle_IRQ_event(unsigned int irq, struct pt_regs * regs, struct irqaction * action) -{ - int status; - int cpu = smp_processor_id(); - - irq_enter(cpu, irq); - - status = 1; /* Force the "do bottom halves" bit */ - - if (!(action->flags & SA_INTERRUPT)) - __sti(); - - do { - status |= action->flags; - action->handler(irq, action->dev_id, regs); - action = action->next; - } while (action); - if (status & SA_SAMPLE_RANDOM) - add_interrupt_randomness(irq); - __cli(); - - irq_exit(cpu, irq); - - return status; -} - -/* - * Generic enable/disable code: this just calls - * down into the PIC-specific version for the actual - * hardware disable after having gotten the irq - * controller lock. - */ - -/** - * disable_irq_nosync - disable an irq without waiting - * @irq: Interrupt to disable - * - * Disable the selected interrupt line. Disables and Enables are - * nested. - * Unlike disable_irq(), this function does not ensure existing - * instances of the IRQ handler have completed before returning. - * - * This function may be called from IRQ context. - */ - -inline void disable_irq_nosync(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - unsigned long flags; - - spin_lock_irqsave(&desc->lock, flags); - if (!desc->depth++) { - desc->status |= IRQ_DISABLED; - desc->handler->disable(irq); - } - spin_unlock_irqrestore(&desc->lock, flags); -} - -/** - * disable_irq - disable an irq and wait for completion - * @irq: Interrupt to disable - * - * Disable the selected interrupt line. Enables and Disables are - * nested. - * This function waits for any pending IRQ handlers for this interrupt - * to complete before returning. If you use this function while - * holding a resource the IRQ handler may need you will deadlock. - * - * This function may be called - with care - from IRQ context. - */ - -void disable_irq(unsigned int irq) -{ - disable_irq_nosync(irq); - - if (!local_irq_count(smp_processor_id())) { - do { - barrier(); - cpu_relax(); - } while (irq_desc[irq].status & IRQ_INPROGRESS); - } -} - -/** - * enable_irq - enable handling of an irq - * @irq: Interrupt to enable - * - * Undoes the effect of one call to disable_irq(). If this - * matches the last disable, processing of interrupts on this - * IRQ line is re-enabled. - * - * This function may be called from IRQ context. - */ - -void enable_irq(unsigned int irq) -{ - irq_desc_t *desc = irq_desc + irq; - unsigned long flags; - - spin_lock_irqsave(&desc->lock, flags); - switch (desc->depth) { - case 1: { - unsigned int status = desc->status & ~IRQ_DISABLED; - desc->status = status; - if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) { - desc->status = status | IRQ_REPLAY; - hw_resend_irq(desc->handler,irq); - } - desc->handler->enable(irq); - /* fall-through */ - } - default: - desc->depth--; - break; - case 0: - printk("enable_irq(%u) unbalanced from %p\n", irq, - __builtin_return_address(0)); - } - spin_unlock_irqrestore(&desc->lock, flags); -} - -/* - * do_IRQ handles all normal device IRQ's (the special - * SMP cross-CPU interrupts have their own specific - * handlers). - */ -asmlinkage unsigned int do_IRQ(int irq, struct pt_regs *regs) -{ - /* - * We ack quickly, we don't want the irq controller - * thinking we're snobs just because some other CPU has - * disabled global interrupts (we have already done the - * INT_ACK cycles, it's too late to try to pretend to the - * controller that we aren't taking the interrupt). - * - * 0 return value means that this irq is already being - * handled by some other CPU. (or is disabled) - */ - int cpu = smp_processor_id(); - irq_desc_t *desc = irq_desc + irq; - struct irqaction * action; - unsigned int status; - - kstat.irqs[cpu][irq]++; - spin_lock(&desc->lock); - desc->handler->ack(irq); - /* - REPLAY is when Linux resends an IRQ that was dropped earlier - WAITING is used by probe to mark irqs that are being tested - */ - status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING); - status |= IRQ_PENDING; /* we _want_ to handle it */ - - /* - * If the IRQ is disabled for whatever reason, we cannot - * use the action we have. - */ - action = NULL; - if (!(status & (IRQ_DISABLED | IRQ_INPROGRESS))) { - action = desc->action; - status &= ~IRQ_PENDING; /* we commit to handling */ - status |= IRQ_INPROGRESS; /* we are handling it */ - } - desc->status = status; - - /* - * If there is no IRQ handler or it was disabled, exit early. - Since we set PENDING, if another processor is handling - a different instance of this same irq, the other processor - will take care of it. - */ - if (!action) - goto out; - - /* - * Edge triggered interrupts need to remember - * pending events. - * This applies to any hw interrupts that allow a second - * instance of the same irq to arrive while we are in do_IRQ - * or in the handler. But the code here only handles the _second_ - * instance of the irq, not the third or fourth. So it is mostly - * useful for irq hardware that does not mask cleanly in an - * SMP environment. - */ - for (;;) { - spin_unlock(&desc->lock); - handle_IRQ_event(irq, regs, action); - spin_lock(&desc->lock); - - if (!(desc->status & IRQ_PENDING)) - break; - desc->status &= ~IRQ_PENDING; - } - desc->status &= ~IRQ_INPROGRESS; -out: - /* - * The ->end() handler has to deal with interrupts which got - * disabled while the handler was running. - */ - desc->handler->end(irq); - spin_unlock(&desc->lock); - - if (softirq_pending(cpu)) - do_softirq(); - - return 1; -} - -/** - * request_irq - allocate an interrupt line - * @irq: Interrupt line to allocate - * @handler: Function to be called when the IRQ occurs - * @irqflags: Interrupt type flags - * @devname: An ascii name for the claiming device - * @dev_id: A cookie passed back to the handler function - * - * This call allocates interrupt resources and enables the - * interrupt line and IRQ handling. From the point this - * call is made your handler function may be invoked. Since - * your handler function must clear any interrupt the board - * raises, you must take care both to initialise your hardware - * and to set up the interrupt handler in the right order. - * - * Dev_id must be globally unique. Normally the address of the - * device data structure is used as the cookie. Since the handler - * receives this value it makes sense to use it. - * - * If your interrupt is shared you must pass a non NULL dev_id - * as this is required when freeing the interrupt. - * - * Flags: - * - * SA_SHIRQ Interrupt is shared - * - * SA_INTERRUPT Disable local interrupts while processing - * - * SA_SAMPLE_RANDOM The interrupt can be used for entropy - * - */ - -int request_irq(unsigned int irq, - void (*handler)(int, void *, struct pt_regs *), - unsigned long irqflags, - const char * devname, - void *dev_id) -{ - int retval; - struct irqaction * action; - -#if 1 - /* - * Sanity-check: shared interrupts should REALLY pass in - * a real dev-ID, otherwise we'll have trouble later trying - * to figure out which interrupt is which (messes up the - * interrupt freeing logic etc). - */ - if (irqflags & SA_SHIRQ) { - if (!dev_id) - printk("Bad boy: %s (at 0x%x) called us without a dev_id!\n", devname, (&irq)[-1]); - } -#endif - - if (irq >= NR_IRQS) - return -EINVAL; - if (!handler) - return -EINVAL; - - action = (struct irqaction *) - kmalloc(sizeof(struct irqaction), GFP_KERNEL); - if (!action) - return -ENOMEM; - - action->handler = handler; - action->flags = irqflags; - action->mask = 0; - action->name = devname; - action->next = NULL; - action->dev_id = dev_id; - - retval = setup_irq(irq, action); - if (retval) - kfree(action); - return retval; -} - -/** - * free_irq - free an interrupt - * @irq: Interrupt line to free - * @dev_id: Device identity to free - * - * Remove an interrupt handler. The handler is removed and if the - * interrupt line is no longer in use by any driver it is disabled. - * On a shared IRQ the caller must ensure the interrupt is disabled - * on the card it drives before calling this function. The function - * does not return until any executing interrupts for this IRQ - * have completed. - * - * This function may be called from interrupt context. - * - * Bugs: Attempting to free an irq in a handler for the same irq hangs - * the machine. - */ - -void free_irq(unsigned int irq, void *dev_id) -{ - irq_desc_t *desc; - struct irqaction **p; - unsigned long flags; - - if (irq >= NR_IRQS) - return; - - desc = irq_desc + irq; - spin_lock_irqsave(&desc->lock,flags); - p = &desc->action; - for (;;) { - struct irqaction * action = *p; - if (action) { - struct irqaction **pp = p; - p = &action->next; - if (action->dev_id != dev_id) - continue; - - /* Found it - now remove it from the list of entries */ - *pp = action->next; - if (!desc->action) { - desc->status |= IRQ_DISABLED; - desc->handler->shutdown(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - -#ifdef CONFIG_SMP - /* Wait to make sure it's not being used on another CPU */ - while (desc->status & IRQ_INPROGRESS) { - barrier(); - cpu_relax(); - } -#endif - kfree(action); - return; - } - printk("Trying to free free IRQ%d\n",irq); - spin_unlock_irqrestore(&desc->lock,flags); - return; - } -} - -/* - * IRQ autodetection code.. - * - * This depends on the fact that any interrupt that - * comes in on to an unassigned handler will get stuck - * with "IRQ_WAITING" cleared and the interrupt - * disabled. - */ - -static DECLARE_MUTEX(probe_sem); - -/** - * probe_irq_on - begin an interrupt autodetect - * - * Commence probing for an interrupt. The interrupts are scanned - * and a mask of potential interrupt lines is returned. - * - */ - -unsigned long probe_irq_on(void) -{ - unsigned int i; - irq_desc_t *desc; - unsigned long val; - unsigned long delay; - - down(&probe_sem); - /* - * something may have generated an irq long ago and we want to - * flush such a longstanding irq before considering it as spurious. - */ - for (i = NR_IRQS-1; i > 0; i--) { - desc = irq_desc + i; - - spin_lock_irq(&desc->lock); - if (!irq_desc[i].action) - irq_desc[i].handler->startup(i); - spin_unlock_irq(&desc->lock); - } - - /* Wait for longstanding interrupts to trigger. */ - for (delay = jiffies + HZ/50; time_after(delay, jiffies); ) - /* about 20ms delay */ synchronize_irq(); - - /* - * enable any unassigned irqs - * (we must startup again here because if a longstanding irq - * happened in the previous stage, it may have masked itself) - */ - for (i = NR_IRQS-1; i > 0; i--) { - desc = irq_desc + i; - - spin_lock_irq(&desc->lock); - if (!desc->action) { - desc->status |= IRQ_AUTODETECT | IRQ_WAITING; - if (desc->handler->startup(i)) - desc->status |= IRQ_PENDING; - } - spin_unlock_irq(&desc->lock); - } - - /* - * Wait for spurious interrupts to trigger - */ - for (delay = jiffies + HZ/10; time_after(delay, jiffies); ) - /* about 100ms delay */ synchronize_irq(); - - /* - * Now filter out any obviously spurious interrupts - */ - val = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - /* It triggered already - consider it spurious. */ - if (!(status & IRQ_WAITING)) { - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } else - if (i < 32) - val |= 1 << i; - } - spin_unlock_irq(&desc->lock); - } - - return val; -} - -/* - * Return a mask of triggered interrupts (this - * can handle only legacy ISA interrupts). - */ - -/** - * probe_irq_mask - scan a bitmap of interrupt lines - * @val: mask of interrupts to consider - * - * Scan the ISA bus interrupt lines and return a bitmap of - * active interrupts. The interrupt probe logic state is then - * returned to its previous value. - * - * Note: we need to scan all the irq's even though we will - * only return ISA irq numbers - just so that we reset them - * all to a known state. - */ -unsigned int probe_irq_mask(unsigned long val) -{ - int i; - unsigned int mask; - - mask = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - if (i < 16 && !(status & IRQ_WAITING)) - mask |= 1 << i; - - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } - spin_unlock_irq(&desc->lock); - } - up(&probe_sem); - - return mask & val; -} - -/* - * Return the one interrupt that triggered (this can - * handle any interrupt source). - */ - -/** - * probe_irq_off - end an interrupt autodetect - * @val: mask of potential interrupts (unused) - * - * Scans the unused interrupt lines and returns the line which - * appears to have triggered the interrupt. If no interrupt was - * found then zero is returned. If more than one interrupt is - * found then minus the first candidate is returned to indicate - * their is doubt. - * - * The interrupt probe logic state is returned to its previous - * value. - * - * BUGS: When used in a module (which arguably shouldnt happen) - * nothing prevents two IRQ probe callers from overlapping. The - * results of this are non-optimal. - */ - -int probe_irq_off(unsigned long val) -{ - int i, irq_found, nr_irqs; - - nr_irqs = 0; - irq_found = 0; - for (i = 0; i < NR_IRQS; i++) { - irq_desc_t *desc = irq_desc + i; - unsigned int status; - - spin_lock_irq(&desc->lock); - status = desc->status; - - if (status & IRQ_AUTODETECT) { - if (!(status & IRQ_WAITING)) { - if (!nr_irqs) - irq_found = i; - nr_irqs++; - } - desc->status = status & ~IRQ_AUTODETECT; - desc->handler->shutdown(i); - } - spin_unlock_irq(&desc->lock); - } - up(&probe_sem); - - if (nr_irqs > 1) - irq_found = -irq_found; - return irq_found; -} - -/* this was setup_x86_irq but it seems pretty generic */ -int setup_irq(unsigned int irq, struct irqaction * new) -{ - int shared = 0; - unsigned long flags; - struct irqaction *old, **p; - irq_desc_t *desc = irq_desc + irq; - - /* - * Some drivers like serial.c use request_irq() heavily, - * so we have to be careful not to interfere with a - * running system. - */ - if (new->flags & SA_SAMPLE_RANDOM) { - /* - * This function might sleep, we want to call it first, - * outside of the atomic block. - * Yes, this might clear the entropy pool if the wrong - * driver is attempted to be loaded, without actually - * installing a new handler, but is this really a problem, - * only the sysadmin is able to do this. - */ - rand_initialize_irq(irq); - } - - /* - * The following block of code has to be executed atomically - */ - spin_lock_irqsave(&desc->lock,flags); - p = &desc->action; - if ((old = *p) != NULL) { - /* Can't share interrupts unless both agree to */ - if (!(old->flags & new->flags & SA_SHIRQ)) { - spin_unlock_irqrestore(&desc->lock,flags); - return -EBUSY; - } - - /* add new interrupt at end of irq queue */ - do { - p = &old->next; - old = *p; - } while (old); - shared = 1; - } - - *p = new; - - if (!shared) { - desc->depth = 0; - desc->status &= ~(IRQ_DISABLED | IRQ_AUTODETECT | IRQ_WAITING); - desc->handler->startup(irq); - } - spin_unlock_irqrestore(&desc->lock,flags); - - register_irq_proc(irq); - return 0; -} - -static struct proc_dir_entry * root_irq_dir; -static struct proc_dir_entry * irq_dir [NR_IRQS]; - -#define HEX_DIGITS 8 - -static unsigned int parse_hex_value (const char *buffer, - unsigned long count, unsigned long *ret) -{ - unsigned char hexnum [HEX_DIGITS]; - unsigned long value; - int i; - - if (!count) - return -EINVAL; - if (count > HEX_DIGITS) - count = HEX_DIGITS; - if (copy_from_user(hexnum, buffer, count)) - return -EFAULT; - - /* - * Parse the first 8 characters as a hex string, any non-hex char - * is end-of-string. '00e1', 'e1', '00E1', 'E1' are all the same. - */ - value = 0; - - for (i = 0; i < count; i++) { - unsigned int c = hexnum[i]; - - switch (c) { - case '0' ... '9': c -= '0'; break; - case 'a' ... 'f': c -= 'a'-10; break; - case 'A' ... 'F': c -= 'A'-10; break; - default: - goto out; - } - value = (value << 4) | c; - } -out: - *ret = value; - return 0; -} - -#if CONFIG_SMP - -static struct proc_dir_entry * smp_affinity_entry [NR_IRQS]; - -static unsigned long irq_affinity [NR_IRQS] = { [0 ... NR_IRQS-1] = ~0UL }; -static int irq_affinity_read_proc (char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - if (count < HEX_DIGITS+1) - return -EINVAL; - return sprintf (page, "%08lx\n", irq_affinity[(long)data]); -} - -static int irq_affinity_write_proc (struct file *file, const char *buffer, - unsigned long count, void *data) -{ - int irq = (long) data, full_count = count, err; - unsigned long new_value; - - if (!irq_desc[irq].handler->set_affinity) - return -EIO; - - err = parse_hex_value(buffer, count, &new_value); - - /* - * Do not allow disabling IRQs completely - it's a too easy - * way to make the system unusable accidentally :-) At least - * one online CPU still has to be targeted. - */ - if (!(new_value & cpu_online_map)) - return -EINVAL; - - irq_affinity[irq] = new_value; - irq_desc[irq].handler->set_affinity(irq, new_value); - - return full_count; -} - -#endif - -static int prof_cpu_mask_read_proc (char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - unsigned long *mask = (unsigned long *) data; - if (count < HEX_DIGITS+1) - return -EINVAL; - return sprintf (page, "%08lx\n", *mask); -} - -static int prof_cpu_mask_write_proc (struct file *file, const char *buffer, - unsigned long count, void *data) -{ - unsigned long *mask = (unsigned long *) data, full_count = count, err; - unsigned long new_value; - - err = parse_hex_value(buffer, count, &new_value); - if (err) - return err; - - *mask = new_value; - return full_count; -} - -#define MAX_NAMELEN 10 - -static void register_irq_proc (unsigned int irq) -{ - char name [MAX_NAMELEN]; - - if (!root_irq_dir || (irq_desc[irq].handler == &no_irq_type) || - irq_dir[irq]) - return; - - memset(name, 0, MAX_NAMELEN); - sprintf(name, "%d", irq); - - /* create /proc/irq/1234 */ - irq_dir[irq] = proc_mkdir(name, root_irq_dir); - -#if CONFIG_SMP - { - struct proc_dir_entry *entry; - - /* create /proc/irq/1234/smp_affinity */ - entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); - - if (entry) { - entry->nlink = 1; - entry->data = (void *)(long)irq; - entry->read_proc = irq_affinity_read_proc; - entry->write_proc = irq_affinity_write_proc; - } - - smp_affinity_entry[irq] = entry; - } -#endif -} - -unsigned long prof_cpu_mask = -1; - -void init_irq_proc (void) -{ - struct proc_dir_entry *entry; - int i; - - /* create /proc/irq */ - root_irq_dir = proc_mkdir("irq", 0); - - /* create /proc/irq/prof_cpu_mask */ - entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir); - - if (!entry) - return; - - entry->nlink = 1; - entry->data = (void *)&prof_cpu_mask; - entry->read_proc = prof_cpu_mask_read_proc; - entry->write_proc = prof_cpu_mask_write_proc; - - /* - * Create entries for all existing IRQs. - */ - for (i = 0; i < NR_IRQS; i++) - register_irq_proc(i); -} - |