https://github.com/torvalds/linux
Tip revision: 521cb40b0c44418a4fd36dc633f575813d59a43d authored by Linus Torvalds on 15 March 2011, 01:20:32 UTC
Linux 2.6.38
Linux 2.6.38
Tip revision: 521cb40
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)
*
* 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.
*/
#undef DEBUG
#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/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/seq_file.h>
#include <linux/cpumask.h>
#include <linux/profile.h>
#include <linux/bitops.h>
#include <linux/list.h>
#include <linux/radix-tree.h>
#include <linux/mutex.h>
#include <linux/bootmem.h>
#include <linux/pci.h>
#include <linux/debugfs.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#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>
#include <asm/udbg.h>
#include <asm/dbell.h>
#include <asm/smp.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#include <asm/firmware.h>
#include <asm/lv1call.h>
#endif
#define CREATE_TRACE_POINTS
#include <asm/trace.h>
DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
EXPORT_PER_CPU_SYMBOL(irq_stat);
int __irq_offset_value;
#ifdef CONFIG_PPC32
EXPORT_SYMBOL(__irq_offset_value);
atomic_t ppc_n_lost_interrupts;
#ifdef CONFIG_TAU_INT
extern int tau_initialized;
extern int tau_interrupts(int);
#endif
#endif /* CONFIG_PPC32 */
#ifdef CONFIG_PPC64
#ifndef CONFIG_SPARSE_IRQ
EXPORT_SYMBOL(irq_desc);
#endif
int distribute_irqs = 1;
static inline notrace unsigned long get_hard_enabled(void)
{
unsigned long enabled;
__asm__ __volatile__("lbz %0,%1(13)"
: "=r" (enabled) : "i" (offsetof(struct paca_struct, hard_enabled)));
return enabled;
}
static inline notrace void set_soft_enabled(unsigned long enable)
{
__asm__ __volatile__("stb %0,%1(13)"
: : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
}
notrace void arch_local_irq_restore(unsigned long en)
{
/*
* get_paca()->soft_enabled = en;
* Is it ever valid to use local_irq_restore(0) when soft_enabled is 1?
* That was allowed before, and in such a case we do need to take care
* that gcc will set soft_enabled directly via r13, not choose to use
* an intermediate register, lest we're preempted to a different cpu.
*/
set_soft_enabled(en);
if (!en)
return;
#ifdef CONFIG_PPC_STD_MMU_64
if (firmware_has_feature(FW_FEATURE_ISERIES)) {
/*
* Do we need to disable preemption here? Not really: in the
* unlikely event that we're preempted to a different cpu in
* between getting r13, loading its lppaca_ptr, and loading
* its any_int, we might call iseries_handle_interrupts without
* an interrupt pending on the new cpu, but that's no disaster,
* is it? And the business of preempting us off the old cpu
* would itself involve a local_irq_restore which handles the
* interrupt to that cpu.
*
* But use "local_paca->lppaca_ptr" instead of "get_lppaca()"
* to avoid any preemption checking added into get_paca().
*/
if (local_paca->lppaca_ptr->int_dword.any_int)
iseries_handle_interrupts();
}
#endif /* CONFIG_PPC_STD_MMU_64 */
/*
* if (get_paca()->hard_enabled) return;
* But again we need to take care that gcc gets hard_enabled directly
* via r13, not choose to use an intermediate register, lest we're
* preempted to a different cpu in between the two instructions.
*/
if (get_hard_enabled())
return;
#if defined(CONFIG_BOOKE) && defined(CONFIG_SMP)
/* Check for pending doorbell interrupts and resend to ourself */
doorbell_check_self();
#endif
/*
* Need to hard-enable interrupts here. Since currently disabled,
* no need to take further asm precautions against preemption; but
* use local_paca instead of get_paca() to avoid preemption checking.
*/
local_paca->hard_enabled = en;
#ifndef CONFIG_BOOKE
/* On server, re-trigger the decrementer if it went negative since
* some processors only trigger on edge transitions of the sign bit.
*
* BookE has a level sensitive decrementer (latches in TSR) so we
* don't need that
*/
if ((int)mfspr(SPRN_DEC) < 0)
mtspr(SPRN_DEC, 1);
#endif /* CONFIG_BOOKE */
/*
* Force the delivery of pending soft-disabled interrupts on PS3.
* Any HV call will have this side effect.
*/
if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
u64 tmp;
lv1_get_version_info(&tmp);
}
__hard_irq_enable();
}
EXPORT_SYMBOL(arch_local_irq_restore);
#endif /* CONFIG_PPC64 */
static int show_other_interrupts(struct seq_file *p, int prec)
{
int j;
#if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT)
if (tau_initialized) {
seq_printf(p, "%*s: ", prec, "TAU");
for_each_online_cpu(j)
seq_printf(p, "%10u ", tau_interrupts(j));
seq_puts(p, " PowerPC Thermal Assist (cpu temp)\n");
}
#endif /* CONFIG_PPC32 && CONFIG_TAU_INT */
seq_printf(p, "%*s: ", prec, "LOC");
for_each_online_cpu(j)
seq_printf(p, "%10u ", per_cpu(irq_stat, j).timer_irqs);
seq_printf(p, " Local timer interrupts\n");
seq_printf(p, "%*s: ", prec, "SPU");
for_each_online_cpu(j)
seq_printf(p, "%10u ", per_cpu(irq_stat, j).spurious_irqs);
seq_printf(p, " Spurious interrupts\n");
seq_printf(p, "%*s: ", prec, "CNT");
for_each_online_cpu(j)
seq_printf(p, "%10u ", per_cpu(irq_stat, j).pmu_irqs);
seq_printf(p, " Performance monitoring interrupts\n");
seq_printf(p, "%*s: ", prec, "MCE");
for_each_online_cpu(j)
seq_printf(p, "%10u ", per_cpu(irq_stat, j).mce_exceptions);
seq_printf(p, " Machine check exceptions\n");
return 0;
}
int show_interrupts(struct seq_file *p, void *v)
{
unsigned long flags, any_count = 0;
int i = *(loff_t *) v, j, prec;
struct irqaction *action;
struct irq_desc *desc;
if (i > nr_irqs)
return 0;
for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
j *= 10;
if (i == nr_irqs)
return show_other_interrupts(p, prec);
/* print header */
if (i == 0) {
seq_printf(p, "%*s", prec + 8, "");
for_each_online_cpu(j)
seq_printf(p, "CPU%-8d", j);
seq_putc(p, '\n');
}
desc = irq_to_desc(i);
if (!desc)
return 0;
raw_spin_lock_irqsave(&desc->lock, flags);
for_each_online_cpu(j)
any_count |= kstat_irqs_cpu(i, j);
action = desc->action;
if (!action && !any_count)
goto out;
seq_printf(p, "%*d: ", prec, i);
for_each_online_cpu(j)
seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
if (desc->chip)
seq_printf(p, " %-16s", desc->chip->name);
else
seq_printf(p, " %-16s", "None");
seq_printf(p, " %-8s", (desc->status & IRQ_LEVEL) ? "Level" : "Edge");
if (action) {
seq_printf(p, " %s", action->name);
while ((action = action->next) != NULL)
seq_printf(p, ", %s", action->name);
}
seq_putc(p, '\n');
out:
raw_spin_unlock_irqrestore(&desc->lock, flags);
return 0;
}
/*
* /proc/stat helpers
*/
u64 arch_irq_stat_cpu(unsigned int cpu)
{
u64 sum = per_cpu(irq_stat, cpu).timer_irqs;
sum += per_cpu(irq_stat, cpu).pmu_irqs;
sum += per_cpu(irq_stat, cpu).mce_exceptions;
sum += per_cpu(irq_stat, cpu).spurious_irqs;
return sum;
}
#ifdef CONFIG_HOTPLUG_CPU
void fixup_irqs(const struct cpumask *map)
{
struct irq_desc *desc;
unsigned int irq;
static int warned;
cpumask_var_t mask;
alloc_cpumask_var(&mask, GFP_KERNEL);
for_each_irq(irq) {
desc = irq_to_desc(irq);
if (!desc)
continue;
if (desc->status & IRQ_PER_CPU)
continue;
cpumask_and(mask, desc->affinity, map);
if (cpumask_any(mask) >= nr_cpu_ids) {
printk("Breaking affinity for irq %i\n", irq);
cpumask_copy(mask, map);
}
if (desc->chip->set_affinity)
desc->chip->set_affinity(irq, mask);
else if (desc->action && !(warned++))
printk("Cannot set affinity for irq %i\n", irq);
}
free_cpumask_var(mask);
local_irq_enable();
mdelay(1);
local_irq_disable();
}
#endif
static inline void handle_one_irq(unsigned int irq)
{
struct thread_info *curtp, *irqtp;
unsigned long saved_sp_limit;
struct irq_desc *desc;
/* Switch to the irq stack to handle this */
curtp = current_thread_info();
irqtp = hardirq_ctx[smp_processor_id()];
if (curtp == irqtp) {
/* We're already on the irq stack, just handle it */
generic_handle_irq(irq);
return;
}
desc = irq_to_desc(irq);
saved_sp_limit = current->thread.ksp_limit;
irqtp->task = curtp->task;
irqtp->flags = 0;
/* Copy the softirq bits in preempt_count so that the
* softirq checks work in the hardirq context. */
irqtp->preempt_count = (irqtp->preempt_count & ~SOFTIRQ_MASK) |
(curtp->preempt_count & SOFTIRQ_MASK);
current->thread.ksp_limit = (unsigned long)irqtp +
_ALIGN_UP(sizeof(struct thread_info), 16);
call_handle_irq(irq, desc, irqtp, desc->handle_irq);
current->thread.ksp_limit = saved_sp_limit;
irqtp->task = NULL;
/* Set any flag that may have been set on the
* alternate stack
*/
if (irqtp->flags)
set_bits(irqtp->flags, &curtp->flags);
}
static inline void check_stack_overflow(void)
{
#ifdef CONFIG_DEBUG_STACKOVERFLOW
long sp;
sp = __get_SP() & (THREAD_SIZE-1);
/* check for stack overflow: is there less than 2KB free? */
if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
printk("do_IRQ: stack overflow: %ld\n",
sp - sizeof(struct thread_info));
dump_stack();
}
#endif
}
void do_IRQ(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
unsigned int irq;
trace_irq_entry(regs);
irq_enter();
check_stack_overflow();
irq = ppc_md.get_irq();
if (irq != NO_IRQ && irq != NO_IRQ_IGNORE)
handle_one_irq(irq);
else if (irq != NO_IRQ_IGNORE)
__get_cpu_var(irq_stat).spurious_irqs++;
irq_exit();
set_irq_regs(old_regs);
#ifdef CONFIG_PPC_ISERIES
if (firmware_has_feature(FW_FEATURE_ISERIES) &&
get_lppaca()->int_dword.fields.decr_int) {
get_lppaca()->int_dword.fields.decr_int = 0;
/* Signal a fake decrementer interrupt */
timer_interrupt(regs);
}
#endif
trace_irq_exit(regs);
}
void __init init_IRQ(void)
{
if (ppc_md.init_IRQ)
ppc_md.init_IRQ();
exc_lvl_ctx_init();
irq_ctx_init();
}
#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
struct thread_info *critirq_ctx[NR_CPUS] __read_mostly;
struct thread_info *dbgirq_ctx[NR_CPUS] __read_mostly;
struct thread_info *mcheckirq_ctx[NR_CPUS] __read_mostly;
void exc_lvl_ctx_init(void)
{
struct thread_info *tp;
int i, hw_cpu;
for_each_possible_cpu(i) {
hw_cpu = get_hard_smp_processor_id(i);
memset((void *)critirq_ctx[hw_cpu], 0, THREAD_SIZE);
tp = critirq_ctx[hw_cpu];
tp->cpu = i;
tp->preempt_count = 0;
#ifdef CONFIG_BOOKE
memset((void *)dbgirq_ctx[hw_cpu], 0, THREAD_SIZE);
tp = dbgirq_ctx[hw_cpu];
tp->cpu = i;
tp->preempt_count = 0;
memset((void *)mcheckirq_ctx[hw_cpu], 0, THREAD_SIZE);
tp = mcheckirq_ctx[hw_cpu];
tp->cpu = i;
tp->preempt_count = HARDIRQ_OFFSET;
#endif
}
}
#endif
struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
void irq_ctx_init(void)
{
struct thread_info *tp;
int i;
for_each_possible_cpu(i) {
memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
tp = softirq_ctx[i];
tp->cpu = i;
tp->preempt_count = 0;
memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
tp = hardirq_ctx[i];
tp->cpu = i;
tp->preempt_count = HARDIRQ_OFFSET;
}
}
static inline void do_softirq_onstack(void)
{
struct thread_info *curtp, *irqtp;
unsigned long saved_sp_limit = current->thread.ksp_limit;
curtp = current_thread_info();
irqtp = softirq_ctx[smp_processor_id()];
irqtp->task = curtp->task;
current->thread.ksp_limit = (unsigned long)irqtp +
_ALIGN_UP(sizeof(struct thread_info), 16);
call_do_softirq(irqtp);
current->thread.ksp_limit = saved_sp_limit;
irqtp->task = NULL;
}
void do_softirq(void)
{
unsigned long flags;
if (in_interrupt())
return;
local_irq_save(flags);
if (local_softirq_pending())
do_softirq_onstack();
local_irq_restore(flags);
}
/*
* IRQ controller and virtual interrupts
*/
static LIST_HEAD(irq_hosts);
static DEFINE_RAW_SPINLOCK(irq_big_lock);
static unsigned int revmap_trees_allocated;
static DEFINE_MUTEX(revmap_trees_mutex);
struct irq_map_entry irq_map[NR_IRQS];
static unsigned int irq_virq_count = NR_IRQS;
static struct irq_host *irq_default_host;
irq_hw_number_t virq_to_hw(unsigned int virq)
{
return irq_map[virq].hwirq;
}
EXPORT_SYMBOL_GPL(virq_to_hw);
static int default_irq_host_match(struct irq_host *h, struct device_node *np)
{
return h->of_node != NULL && h->of_node == np;
}
struct irq_host *irq_alloc_host(struct device_node *of_node,
unsigned int revmap_type,
unsigned int revmap_arg,
struct irq_host_ops *ops,
irq_hw_number_t inval_irq)
{
struct irq_host *host;
unsigned int size = sizeof(struct irq_host);
unsigned int i;
unsigned int *rmap;
unsigned long flags;
/* Allocate structure and revmap table if using linear mapping */
if (revmap_type == IRQ_HOST_MAP_LINEAR)
size += revmap_arg * sizeof(unsigned int);
host = zalloc_maybe_bootmem(size, GFP_KERNEL);
if (host == NULL)
return NULL;
/* Fill structure */
host->revmap_type = revmap_type;
host->inval_irq = inval_irq;
host->ops = ops;
host->of_node = of_node_get(of_node);
if (host->ops->match == NULL)
host->ops->match = default_irq_host_match;
raw_spin_lock_irqsave(&irq_big_lock, flags);
/* If it's a legacy controller, check for duplicates and
* mark it as allocated (we use irq 0 host pointer for that
*/
if (revmap_type == IRQ_HOST_MAP_LEGACY) {
if (irq_map[0].host != NULL) {
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
/* If we are early boot, we can't free the structure,
* too bad...
* this will be fixed once slab is made available early
* instead of the current cruft
*/
if (mem_init_done) {
of_node_put(host->of_node);
kfree(host);
}
return NULL;
}
irq_map[0].host = host;
}
list_add(&host->link, &irq_hosts);
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
/* Additional setups per revmap type */
switch(revmap_type) {
case IRQ_HOST_MAP_LEGACY:
/* 0 is always the invalid number for legacy */
host->inval_irq = 0;
/* setup us as the host for all legacy interrupts */
for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
irq_map[i].hwirq = i;
smp_wmb();
irq_map[i].host = host;
smp_wmb();
/* Clear norequest flags */
irq_to_desc(i)->status &= ~IRQ_NOREQUEST;
/* Legacy flags are left to default at this point,
* one can then use irq_create_mapping() to
* explicitly change them
*/
ops->map(host, i, i);
}
break;
case IRQ_HOST_MAP_LINEAR:
rmap = (unsigned int *)(host + 1);
for (i = 0; i < revmap_arg; i++)
rmap[i] = NO_IRQ;
host->revmap_data.linear.size = revmap_arg;
smp_wmb();
host->revmap_data.linear.revmap = rmap;
break;
default:
break;
}
pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
return host;
}
struct irq_host *irq_find_host(struct device_node *node)
{
struct irq_host *h, *found = NULL;
unsigned long flags;
/* We might want to match the legacy controller last since
* it might potentially be set to match all interrupts in
* the absence of a device node. This isn't a problem so far
* yet though...
*/
raw_spin_lock_irqsave(&irq_big_lock, flags);
list_for_each_entry(h, &irq_hosts, link)
if (h->ops->match(h, node)) {
found = h;
break;
}
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
return found;
}
EXPORT_SYMBOL_GPL(irq_find_host);
void irq_set_default_host(struct irq_host *host)
{
pr_debug("irq: Default host set to @0x%p\n", host);
irq_default_host = host;
}
void irq_set_virq_count(unsigned int count)
{
pr_debug("irq: Trying to set virq count to %d\n", count);
BUG_ON(count < NUM_ISA_INTERRUPTS);
if (count < NR_IRQS)
irq_virq_count = count;
}
static int irq_setup_virq(struct irq_host *host, unsigned int virq,
irq_hw_number_t hwirq)
{
struct irq_desc *desc;
desc = irq_to_desc_alloc_node(virq, 0);
if (!desc) {
pr_debug("irq: -> allocating desc failed\n");
goto error;
}
/* Clear IRQ_NOREQUEST flag */
desc->status &= ~IRQ_NOREQUEST;
/* map it */
smp_wmb();
irq_map[virq].hwirq = hwirq;
smp_mb();
if (host->ops->map(host, virq, hwirq)) {
pr_debug("irq: -> mapping failed, freeing\n");
goto error;
}
return 0;
error:
irq_free_virt(virq, 1);
return -1;
}
unsigned int irq_create_direct_mapping(struct irq_host *host)
{
unsigned int virq;
if (host == NULL)
host = irq_default_host;
BUG_ON(host == NULL);
WARN_ON(host->revmap_type != IRQ_HOST_MAP_NOMAP);
virq = irq_alloc_virt(host, 1, 0);
if (virq == NO_IRQ) {
pr_debug("irq: create_direct virq allocation failed\n");
return NO_IRQ;
}
pr_debug("irq: create_direct obtained virq %d\n", virq);
if (irq_setup_virq(host, virq, virq))
return NO_IRQ;
return virq;
}
unsigned int irq_create_mapping(struct irq_host *host,
irq_hw_number_t hwirq)
{
unsigned int virq, hint;
pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
/* Look for default host if nececssary */
if (host == NULL)
host = irq_default_host;
if (host == NULL) {
printk(KERN_WARNING "irq_create_mapping called for"
" NULL host, hwirq=%lx\n", hwirq);
WARN_ON(1);
return NO_IRQ;
}
pr_debug("irq: -> using host @%p\n", host);
/* Check if mapping already exist, if it does, call
* host->ops->map() to update the flags
*/
virq = irq_find_mapping(host, hwirq);
if (virq != NO_IRQ) {
if (host->ops->remap)
host->ops->remap(host, virq, hwirq);
pr_debug("irq: -> existing mapping on virq %d\n", virq);
return virq;
}
/* Get a virtual interrupt number */
if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
/* Handle legacy */
virq = (unsigned int)hwirq;
if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
return NO_IRQ;
return virq;
} else {
/* Allocate a virtual interrupt number */
hint = hwirq % irq_virq_count;
virq = irq_alloc_virt(host, 1, hint);
if (virq == NO_IRQ) {
pr_debug("irq: -> virq allocation failed\n");
return NO_IRQ;
}
}
if (irq_setup_virq(host, virq, hwirq))
return NO_IRQ;
printk(KERN_DEBUG "irq: irq %lu on host %s mapped to virtual irq %u\n",
hwirq, host->of_node ? host->of_node->full_name : "null", virq);
return virq;
}
EXPORT_SYMBOL_GPL(irq_create_mapping);
unsigned int irq_create_of_mapping(struct device_node *controller,
const u32 *intspec, unsigned int intsize)
{
struct irq_host *host;
irq_hw_number_t hwirq;
unsigned int type = IRQ_TYPE_NONE;
unsigned int virq;
if (controller == NULL)
host = irq_default_host;
else
host = irq_find_host(controller);
if (host == NULL) {
printk(KERN_WARNING "irq: no irq host found for %s !\n",
controller->full_name);
return NO_IRQ;
}
/* If host has no translation, then we assume interrupt line */
if (host->ops->xlate == NULL)
hwirq = intspec[0];
else {
if (host->ops->xlate(host, controller, intspec, intsize,
&hwirq, &type))
return NO_IRQ;
}
/* Create mapping */
virq = irq_create_mapping(host, hwirq);
if (virq == NO_IRQ)
return virq;
/* Set type if specified and different than the current one */
if (type != IRQ_TYPE_NONE &&
type != (irq_to_desc(virq)->status & IRQF_TRIGGER_MASK))
set_irq_type(virq, type);
return virq;
}
EXPORT_SYMBOL_GPL(irq_create_of_mapping);
void irq_dispose_mapping(unsigned int virq)
{
struct irq_host *host;
irq_hw_number_t hwirq;
if (virq == NO_IRQ)
return;
host = irq_map[virq].host;
WARN_ON (host == NULL);
if (host == NULL)
return;
/* Never unmap legacy interrupts */
if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
return;
/* remove chip and handler */
set_irq_chip_and_handler(virq, NULL, NULL);
/* Make sure it's completed */
synchronize_irq(virq);
/* Tell the PIC about it */
if (host->ops->unmap)
host->ops->unmap(host, virq);
smp_mb();
/* Clear reverse map */
hwirq = irq_map[virq].hwirq;
switch(host->revmap_type) {
case IRQ_HOST_MAP_LINEAR:
if (hwirq < host->revmap_data.linear.size)
host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
break;
case IRQ_HOST_MAP_TREE:
/*
* Check if radix tree allocated yet, if not then nothing to
* remove.
*/
smp_rmb();
if (revmap_trees_allocated < 1)
break;
mutex_lock(&revmap_trees_mutex);
radix_tree_delete(&host->revmap_data.tree, hwirq);
mutex_unlock(&revmap_trees_mutex);
break;
}
/* Destroy map */
smp_mb();
irq_map[virq].hwirq = host->inval_irq;
/* Set some flags */
irq_to_desc(virq)->status |= IRQ_NOREQUEST;
/* Free it */
irq_free_virt(virq, 1);
}
EXPORT_SYMBOL_GPL(irq_dispose_mapping);
unsigned int irq_find_mapping(struct irq_host *host,
irq_hw_number_t hwirq)
{
unsigned int i;
unsigned int hint = hwirq % irq_virq_count;
/* Look for default host if nececssary */
if (host == NULL)
host = irq_default_host;
if (host == NULL)
return NO_IRQ;
/* legacy -> bail early */
if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
return hwirq;
/* Slow path does a linear search of the map */
if (hint < NUM_ISA_INTERRUPTS)
hint = NUM_ISA_INTERRUPTS;
i = hint;
do {
if (irq_map[i].host == host &&
irq_map[i].hwirq == hwirq)
return i;
i++;
if (i >= irq_virq_count)
i = NUM_ISA_INTERRUPTS;
} while(i != hint);
return NO_IRQ;
}
EXPORT_SYMBOL_GPL(irq_find_mapping);
unsigned int irq_radix_revmap_lookup(struct irq_host *host,
irq_hw_number_t hwirq)
{
struct irq_map_entry *ptr;
unsigned int virq;
WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
/*
* Check if the radix tree exists and has bee initialized.
* If not, we fallback to slow mode
*/
if (revmap_trees_allocated < 2)
return irq_find_mapping(host, hwirq);
/* Now try to resolve */
/*
* No rcu_read_lock(ing) needed, the ptr returned can't go under us
* as it's referencing an entry in the static irq_map table.
*/
ptr = radix_tree_lookup(&host->revmap_data.tree, hwirq);
/*
* If found in radix tree, then fine.
* Else fallback to linear lookup - this should not happen in practice
* as it means that we failed to insert the node in the radix tree.
*/
if (ptr)
virq = ptr - irq_map;
else
virq = irq_find_mapping(host, hwirq);
return virq;
}
void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,
irq_hw_number_t hwirq)
{
WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
/*
* Check if the radix tree exists yet.
* If not, then the irq will be inserted into the tree when it gets
* initialized.
*/
smp_rmb();
if (revmap_trees_allocated < 1)
return;
if (virq != NO_IRQ) {
mutex_lock(&revmap_trees_mutex);
radix_tree_insert(&host->revmap_data.tree, hwirq,
&irq_map[virq]);
mutex_unlock(&revmap_trees_mutex);
}
}
unsigned int irq_linear_revmap(struct irq_host *host,
irq_hw_number_t hwirq)
{
unsigned int *revmap;
WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
/* Check revmap bounds */
if (unlikely(hwirq >= host->revmap_data.linear.size))
return irq_find_mapping(host, hwirq);
/* Check if revmap was allocated */
revmap = host->revmap_data.linear.revmap;
if (unlikely(revmap == NULL))
return irq_find_mapping(host, hwirq);
/* Fill up revmap with slow path if no mapping found */
if (unlikely(revmap[hwirq] == NO_IRQ))
revmap[hwirq] = irq_find_mapping(host, hwirq);
return revmap[hwirq];
}
unsigned int irq_alloc_virt(struct irq_host *host,
unsigned int count,
unsigned int hint)
{
unsigned long flags;
unsigned int i, j, found = NO_IRQ;
if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
return NO_IRQ;
raw_spin_lock_irqsave(&irq_big_lock, flags);
/* Use hint for 1 interrupt if any */
if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
hint < irq_virq_count && irq_map[hint].host == NULL) {
found = hint;
goto hint_found;
}
/* Look for count consecutive numbers in the allocatable
* (non-legacy) space
*/
for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
if (irq_map[i].host != NULL)
j = 0;
else
j++;
if (j == count) {
found = i - count + 1;
break;
}
}
if (found == NO_IRQ) {
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
return NO_IRQ;
}
hint_found:
for (i = found; i < (found + count); i++) {
irq_map[i].hwirq = host->inval_irq;
smp_wmb();
irq_map[i].host = host;
}
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
return found;
}
void irq_free_virt(unsigned int virq, unsigned int count)
{
unsigned long flags;
unsigned int i;
WARN_ON (virq < NUM_ISA_INTERRUPTS);
WARN_ON (count == 0 || (virq + count) > irq_virq_count);
raw_spin_lock_irqsave(&irq_big_lock, flags);
for (i = virq; i < (virq + count); i++) {
struct irq_host *host;
if (i < NUM_ISA_INTERRUPTS ||
(virq + count) > irq_virq_count)
continue;
host = irq_map[i].host;
irq_map[i].hwirq = host->inval_irq;
smp_wmb();
irq_map[i].host = NULL;
}
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
}
int arch_early_irq_init(void)
{
struct irq_desc *desc;
int i;
for (i = 0; i < NR_IRQS; i++) {
desc = irq_to_desc(i);
if (desc)
desc->status |= IRQ_NOREQUEST;
}
return 0;
}
int arch_init_chip_data(struct irq_desc *desc, int node)
{
desc->status |= IRQ_NOREQUEST;
return 0;
}
/* We need to create the radix trees late */
static int irq_late_init(void)
{
struct irq_host *h;
unsigned int i;
/*
* No mutual exclusion with respect to accessors of the tree is needed
* here as the synchronization is done via the state variable
* revmap_trees_allocated.
*/
list_for_each_entry(h, &irq_hosts, link) {
if (h->revmap_type == IRQ_HOST_MAP_TREE)
INIT_RADIX_TREE(&h->revmap_data.tree, GFP_KERNEL);
}
/*
* Make sure the radix trees inits are visible before setting
* the flag
*/
smp_wmb();
revmap_trees_allocated = 1;
/*
* Insert the reverse mapping for those interrupts already present
* in irq_map[].
*/
mutex_lock(&revmap_trees_mutex);
for (i = 0; i < irq_virq_count; i++) {
if (irq_map[i].host &&
(irq_map[i].host->revmap_type == IRQ_HOST_MAP_TREE))
radix_tree_insert(&irq_map[i].host->revmap_data.tree,
irq_map[i].hwirq, &irq_map[i]);
}
mutex_unlock(&revmap_trees_mutex);
/*
* Make sure the radix trees insertions are visible before setting
* the flag
*/
smp_wmb();
revmap_trees_allocated = 2;
return 0;
}
arch_initcall(irq_late_init);
#ifdef CONFIG_VIRQ_DEBUG
static int virq_debug_show(struct seq_file *m, void *private)
{
unsigned long flags;
struct irq_desc *desc;
const char *p;
static const char none[] = "none";
int i;
seq_printf(m, "%-5s %-7s %-15s %s\n", "virq", "hwirq",
"chip name", "host name");
for (i = 1; i < nr_irqs; i++) {
desc = irq_to_desc(i);
if (!desc)
continue;
raw_spin_lock_irqsave(&desc->lock, flags);
if (desc->action && desc->action->handler) {
seq_printf(m, "%5d ", i);
seq_printf(m, "0x%05lx ", virq_to_hw(i));
if (desc->chip && desc->chip->name)
p = desc->chip->name;
else
p = none;
seq_printf(m, "%-15s ", p);
if (irq_map[i].host && irq_map[i].host->of_node)
p = irq_map[i].host->of_node->full_name;
else
p = none;
seq_printf(m, "%s\n", p);
}
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
return 0;
}
static int virq_debug_open(struct inode *inode, struct file *file)
{
return single_open(file, virq_debug_show, inode->i_private);
}
static const struct file_operations virq_debug_fops = {
.open = virq_debug_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int __init irq_debugfs_init(void)
{
if (debugfs_create_file("virq_mapping", S_IRUGO, powerpc_debugfs_root,
NULL, &virq_debug_fops) == NULL)
return -ENOMEM;
return 0;
}
__initcall(irq_debugfs_init);
#endif /* CONFIG_VIRQ_DEBUG */
#ifdef CONFIG_PPC64
static int __init setup_noirqdistrib(char *str)
{
distribute_irqs = 0;
return 1;
}
__setup("noirqdistrib", setup_noirqdistrib);
#endif /* CONFIG_PPC64 */