linux_dsm_epyc7002/arch/c6x/kernel/irq.c
Aurelien Jacquiot ec500af305 C6X: interrupt handling
Original port to early 2.6 kernel using TI COFF toolchain.
Brought up to date by Mark Salter <msalter@redhat.com>

Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2011-10-06 19:47:54 -04:00

729 lines
17 KiB
C

/*
* Copyright (C) 2011 Texas Instruments Incorporated
*
* This borrows heavily from powerpc version, which is:
*
* 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.
*/
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/radix-tree.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <asm/megamod-pic.h>
unsigned long irq_err_count;
static DEFINE_RAW_SPINLOCK(core_irq_lock);
static void mask_core_irq(struct irq_data *data)
{
unsigned int prio = data->irq;
BUG_ON(prio < 4 || prio >= NR_PRIORITY_IRQS);
raw_spin_lock(&core_irq_lock);
and_creg(IER, ~(1 << prio));
raw_spin_unlock(&core_irq_lock);
}
static void unmask_core_irq(struct irq_data *data)
{
unsigned int prio = data->irq;
raw_spin_lock(&core_irq_lock);
or_creg(IER, 1 << prio);
raw_spin_unlock(&core_irq_lock);
}
static struct irq_chip core_chip = {
.name = "core",
.irq_mask = mask_core_irq,
.irq_unmask = unmask_core_irq,
};
asmlinkage void c6x_do_IRQ(unsigned int prio, struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
irq_enter();
BUG_ON(prio < 4 || prio >= NR_PRIORITY_IRQS);
generic_handle_irq(prio);
irq_exit();
set_irq_regs(old_regs);
}
static struct irq_host *core_host;
static int core_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
if (hw < 4 || hw >= NR_PRIORITY_IRQS)
return -EINVAL;
irq_set_status_flags(virq, IRQ_LEVEL);
irq_set_chip_and_handler(virq, &core_chip, handle_level_irq);
return 0;
}
static struct irq_host_ops core_host_ops = {
.map = core_host_map,
};
void __init init_IRQ(void)
{
struct device_node *np;
/* Mask all priority IRQs */
and_creg(IER, ~0xfff0);
np = of_find_compatible_node(NULL, NULL, "ti,c64x+core-pic");
if (np != NULL) {
/* create the core host */
core_host = irq_alloc_host(np, IRQ_HOST_MAP_PRIORITY, 0,
&core_host_ops, 0);
if (core_host)
irq_set_default_host(core_host);
of_node_put(np);
}
printk(KERN_INFO "Core interrupt controller initialized\n");
/* now we're ready for other SoC controllers */
megamod_pic_init();
/* Clear all general IRQ flags */
set_creg(ICR, 0xfff0);
}
void ack_bad_irq(int irq)
{
printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
irq_err_count++;
}
int arch_show_interrupts(struct seq_file *p, int prec)
{
seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
return 0;
}
/*
* IRQ controller and virtual interrupts
*/
/* The main irq map itself is an array of NR_IRQ entries containing the
* associate host and irq number. An entry with a host of NULL is free.
* An entry can be allocated if it's free, the allocator always then sets
* hwirq first to the host's invalid irq number and then fills ops.
*/
struct irq_map_entry {
irq_hw_number_t hwirq;
struct irq_host *host;
};
static LIST_HEAD(irq_hosts);
static DEFINE_RAW_SPINLOCK(irq_big_lock);
static DEFINE_MUTEX(revmap_trees_mutex);
static 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 irqd_to_hwirq(struct irq_data *d)
{
return irq_map[d->irq].hwirq;
}
EXPORT_SYMBOL_GPL(irqd_to_hwirq);
irq_hw_number_t virq_to_hw(unsigned int virq)
{
return irq_map[virq].hwirq;
}
EXPORT_SYMBOL_GPL(virq_to_hw);
bool virq_is_host(unsigned int virq, struct irq_host *host)
{
return irq_map[virq].host == host;
}
EXPORT_SYMBOL_GPL(virq_is_host);
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 = kzalloc(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);
/* Check for the priority controller. */
if (revmap_type == IRQ_HOST_MAP_PRIORITY) {
if (irq_map[0].host != NULL) {
raw_spin_unlock_irqrestore(&irq_big_lock, flags);
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_PRIORITY:
/* 0 is always the invalid number for priority */
host->inval_irq = 0;
/* setup us as the host for all priority interrupts */
for (i = 1; i < NR_PRIORITY_IRQS; i++) {
irq_map[i].hwirq = i;
smp_wmb();
irq_map[i].host = host;
smp_wmb();
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;
case IRQ_HOST_MAP_TREE:
INIT_RADIX_TREE(&host->revmap_data.tree, GFP_KERNEL);
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 < NR_PRIORITY_IRQS);
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)
{
int res;
res = irq_alloc_desc_at(virq, 0);
if (res != virq) {
pr_debug("irq: -> allocating desc failed\n");
goto error;
}
/* 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 errdesc;
}
irq_clear_status_flags(virq, IRQ_NOREQUEST);
return 0;
errdesc:
irq_free_descs(virq, 1);
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 exists */
virq = irq_find_mapping(host, hwirq);
if (virq != NO_IRQ) {
pr_debug("irq: -> existing mapping on virq %d\n", virq);
return virq;
}
/* 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;
pr_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 != (irqd_get_trigger_type(irq_get_irq_data(virq))))
irq_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;
/* Never unmap priority interrupts */
if (virq < NR_PRIORITY_IRQS)
return;
host = irq_map[virq].host;
if (WARN_ON(host == NULL))
return;
irq_set_status_flags(virq, IRQ_NOREQUEST);
/* remove chip and handler */
irq_set_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:
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;
irq_free_descs(virq, 1);
/* 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;
/* Slow path does a linear search of the map */
i = hint;
do {
if (irq_map[i].host == host &&
irq_map[i].hwirq == hwirq)
return i;
i++;
if (i >= irq_virq_count)
i = 4;
} 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;
if (WARN_ON_ONCE(host->revmap_type != IRQ_HOST_MAP_TREE))
return irq_find_mapping(host, hwirq);
/*
* The ptr returned references the static global irq_map.
* but freeing an irq can delete nodes along the path to
* do the lookup via call_rcu.
*/
rcu_read_lock();
ptr = radix_tree_lookup(&host->revmap_data.tree, hwirq);
rcu_read_unlock();
/*
* 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)
{
if (WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE))
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;
if (WARN_ON_ONCE(host->revmap_type != IRQ_HOST_MAP_LINEAR))
return irq_find_mapping(host, hwirq);
/* 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 - NR_PRIORITY_IRQS))
return NO_IRQ;
raw_spin_lock_irqsave(&irq_big_lock, flags);
/* Use hint for 1 interrupt if any */
if (count == 1 && hint >= NR_PRIORITY_IRQS &&
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 = NR_PRIORITY_IRQS, 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 < NR_PRIORITY_IRQS);
WARN_ON(count == 0 || (virq + count) > irq_virq_count);
if (virq < NR_PRIORITY_IRQS) {
if (virq + count < NR_PRIORITY_IRQS)
return;
count -= NR_PRIORITY_IRQS - virq;
virq = NR_PRIORITY_IRQS;
}
if (count > irq_virq_count || virq > irq_virq_count - count) {
if (virq > irq_virq_count)
return;
count = irq_virq_count - virq;
}
raw_spin_lock_irqsave(&irq_big_lock, flags);
for (i = virq; i < (virq + count); i++) {
struct irq_host *host;
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);
}
#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";
void *data;
int i;
seq_printf(m, "%-5s %-7s %-15s %-18s %s\n", "virq", "hwirq",
"chip name", "chip data", "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) {
struct irq_chip *chip;
seq_printf(m, "%5d ", i);
seq_printf(m, "0x%05lx ", irq_map[i].hwirq);
chip = irq_desc_get_chip(desc);
if (chip && chip->name)
p = chip->name;
else
p = none;
seq_printf(m, "%-15s ", p);
data = irq_desc_get_chip_data(desc);
seq_printf(m, "0x%16p ", data);
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;
}
device_initcall(irq_debugfs_init);
#endif /* CONFIG_VIRQ_DEBUG */