linux/arch/powerpc/kernel/irq.c
Sebastien Dugue 967e012ef3 powerpc: Separate the irq radix tree insertion and lookup
irq_radix_revmap() currently serves 2 purposes, irq mapping lookup
and insertion which happen in interrupt and process context respectively.

Separate the function into its 2 components, one for lookup only and one
for insertion only.

Fix the only user of the revmap tree (XICS) to use the new functions.

Also, move the insertion into the radix tree of those irqs that were
requested before it was initialized at said tree initialization.

Mutual exclusion between the tree initialization and readers/writers is
handled via a state variable (revmap_trees_allocated) set to 1 when the tree
has been initialized and set to 2 after the already requested irqs have been
inserted in the tree by the init path. This state is checked before any reader
or writer access just like we used to check for tree.gfp_mask != 0 before.

Finally, now that we're not any longer inserting nodes into the radix-tree
in interrupt context, turn the GFP_ATOMIC allocations into GFP_KERNEL ones.

Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:44 -07:00

1162 lines
28 KiB
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 <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>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#include <asm/firmware.h>
#include <asm/lv1call.h>
#endif
int __irq_offset_value;
static int ppc_spurious_interrupts;
#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
EXPORT_SYMBOL(irq_desc);
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 raw_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;
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();
}
/*
* 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;
/*
* 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;
if ((int)mfspr(SPRN_DEC) < 0)
mtspr(SPRN_DEC, 1);
/*
* 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(raw_local_irq_restore);
#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->chip)
seq_printf(p, " %s ", desc->chip->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) {
#if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT)
if (tau_initialized){
seq_puts(p, "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, "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_desc[irq].affinity, map);
if (any_online_cpu(mask) == NR_CPUS) {
printk("Breaking affinity for irq %i\n", irq);
mask = map;
}
if (irq_desc[irq].chip->set_affinity)
irq_desc[irq].chip->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
void do_IRQ(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
unsigned 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 NO_IRQ to
* indicate there are no more pending.
* The value NO_IRQ_IGNORE is for buggy hardware and means that this
* IRQ has already been handled. -- Tom
*/
irq = ppc_md.get_irq();
if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
#ifdef CONFIG_IRQSTACKS
/* Switch to the irq stack to handle this */
curtp = current_thread_info();
irqtp = hardirq_ctx[smp_processor_id()];
if (curtp != irqtp) {
struct irq_desc *desc = irq_desc + irq;
void *handler = desc->handle_irq;
unsigned long saved_sp_limit = current->thread.ksp_limit;
if (handler == NULL)
handler = &__do_IRQ;
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, handler);
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);
} else
#endif
generic_handle_irq(irq);
} else if (irq != NO_IRQ_IGNORE)
/* That's not SMP safe ... but who cares ? */
ppc_spurious_interrupts++;
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
}
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;
for_each_possible_cpu(i) {
memset((void *)critirq_ctx[i], 0, THREAD_SIZE);
tp = critirq_ctx[i];
tp->cpu = i;
tp->preempt_count = 0;
#ifdef CONFIG_BOOKE
memset((void *)dbgirq_ctx[i], 0, THREAD_SIZE);
tp = dbgirq_ctx[i];
tp->cpu = i;
tp->preempt_count = 0;
memset((void *)mcheckirq_ctx[i], 0, THREAD_SIZE);
tp = mcheckirq_ctx[i];
tp->cpu = i;
tp->preempt_count = HARDIRQ_OFFSET;
#endif
}
}
#endif
#ifdef CONFIG_IRQSTACKS
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;
}
#else
#define do_softirq_onstack() __do_softirq()
#endif /* CONFIG_IRQSTACKS */
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_SPINLOCK(irq_big_lock);
static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
static unsigned int irq_radix_writer;
static unsigned int revmap_trees_allocated;
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;
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) {
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)
kfree(host);
return NULL;
}
irq_map[0].host = host;
}
list_add(&host->link, &irq_hosts);
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 */
get_irq_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...
*/
spin_lock_irqsave(&irq_big_lock, flags);
list_for_each_entry(h, &irq_hosts, link)
if (h->ops->match(h, node)) {
found = h;
break;
}
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;
}
/* radix tree not lockless safe ! we use a brlock-type mecanism
* for now, until we can use a lockless radix tree
*/
static void irq_radix_wrlock(unsigned long *flags)
{
unsigned int cpu, ok;
spin_lock_irqsave(&irq_big_lock, *flags);
irq_radix_writer = 1;
smp_mb();
do {
barrier();
ok = 1;
for_each_possible_cpu(cpu) {
if (per_cpu(irq_radix_reader, cpu)) {
ok = 0;
break;
}
}
if (!ok)
cpu_relax();
} while(!ok);
}
static void irq_radix_wrunlock(unsigned long flags)
{
smp_wmb();
irq_radix_writer = 0;
spin_unlock_irqrestore(&irq_big_lock, flags);
}
static void irq_radix_rdlock(unsigned long *flags)
{
local_irq_save(*flags);
__get_cpu_var(irq_radix_reader) = 1;
smp_mb();
if (likely(irq_radix_writer == 0))
return;
__get_cpu_var(irq_radix_reader) = 0;
smp_wmb();
spin_lock(&irq_big_lock);
__get_cpu_var(irq_radix_reader) = 1;
spin_unlock(&irq_big_lock);
}
static void irq_radix_rdunlock(unsigned long flags)
{
__get_cpu_var(irq_radix_reader) = 0;
local_irq_restore(flags);
}
static int irq_setup_virq(struct irq_host *host, unsigned int virq,
irq_hw_number_t hwirq)
{
/* Clear IRQ_NOREQUEST flag */
get_irq_desc(virq)->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");
irq_free_virt(virq, 1);
return -1;
}
return 0;
}
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;
}
}
pr_debug("irq: -> obtained virq %d\n", virq);
if (irq_setup_virq(host, virq, hwirq))
return NO_IRQ;
return virq;
}
EXPORT_SYMBOL_GPL(irq_create_mapping);
unsigned int irq_create_of_mapping(struct device_node *controller,
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 != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
set_irq_type(virq, type);
return virq;
}
EXPORT_SYMBOL_GPL(irq_create_of_mapping);
unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
{
struct of_irq oirq;
if (of_irq_map_one(dev, index, &oirq))
return NO_IRQ;
return irq_create_of_mapping(oirq.controller, oirq.specifier,
oirq.size);
}
EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
void irq_dispose_mapping(unsigned int virq)
{
struct irq_host *host;
irq_hw_number_t hwirq;
unsigned long flags;
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;
irq_radix_wrlock(&flags);
radix_tree_delete(&host->revmap_data.tree, hwirq);
irq_radix_wrunlock(flags);
break;
}
/* Destroy map */
smp_mb();
irq_map[virq].hwirq = host->inval_irq;
/* Set some flags */
get_irq_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;
unsigned long flags;
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 */
irq_radix_rdlock(&flags);
ptr = radix_tree_lookup(&host->revmap_data.tree, hwirq);
irq_radix_rdunlock(flags);
/*
* 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)
{
unsigned long flags;
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) {
irq_radix_wrlock(&flags);
radix_tree_insert(&host->revmap_data.tree, hwirq,
&irq_map[virq]);
irq_radix_wrunlock(flags);
}
}
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;
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) {
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;
}
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);
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;
}
spin_unlock_irqrestore(&irq_big_lock, flags);
}
void irq_early_init(void)
{
unsigned int i;
for (i = 0; i < NR_IRQS; i++)
get_irq_desc(i)->status |= IRQ_NOREQUEST;
}
/* We need to create the radix trees late */
static int irq_late_init(void)
{
struct irq_host *h;
unsigned long flags;
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[].
*/
irq_radix_wrlock(&flags);
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]);
}
irq_radix_wrunlock(flags);
/*
* 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;
irq_desc_t *desc;
const char *p;
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 = get_irq_desc(i);
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->typename)
p = desc->chip->typename;
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);
}
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 */