linux/drivers/irqchip/irq-bcm7120-l2.c
Kevin Cernekee ca40f1b23d IRQCHIP: bcm7120-l2: Split STB-specific logic into its own function
The BCM7xxx instances of this block (listed in the register manual as
simply "IRQ0") all have the following items in common:

 - brcm,int-map-mask: for routing different bits in the L2 to different
   parent IRQs

 - brcm,int-fwd-mask: for hardwiring certain IRQs to bypass the L2 and
   use dedicated L1 lines

 - one enable/status pair (32 bits only)

Much of the driver code can be shared with BCM3380-style controllers, but
in order to do this cleanly, let's split out the BCM7xxx-specific logic
first.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: jaedon.shin@gmail.com
Cc: abrestic@chromium.org
Cc: tglx@linutronix.de
Cc: jason@lakedaemon.net
Cc: jogo@openwrt.org
Cc: arnd@arndb.de
Cc: computersforpeace@gmail.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8842/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-04-01 17:21:37 +02:00

284 lines
7.3 KiB
C

/*
* Broadcom BCM7120 style Level 2 interrupt controller driver
*
* Copyright (C) 2014 Broadcom Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kconfig.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/irqdomain.h>
#include <linux/reboot.h>
#include <linux/bitops.h>
#include <linux/irqchip/chained_irq.h>
#include "irqchip.h"
/* Register offset in the L2 interrupt controller */
#define IRQEN 0x00
#define IRQSTAT 0x04
#define MAX_WORDS 4
#define MAX_MAPPINGS (MAX_WORDS * 2)
#define IRQS_PER_WORD 32
struct bcm7120_l2_intc_data {
unsigned int n_words;
void __iomem *map_base[MAX_MAPPINGS];
void __iomem *pair_base[MAX_WORDS];
int en_offset[MAX_WORDS];
int stat_offset[MAX_WORDS];
struct irq_domain *domain;
bool can_wake;
u32 irq_fwd_mask[MAX_WORDS];
u32 irq_map_mask[MAX_WORDS];
int num_parent_irqs;
const __be32 *map_mask_prop;
};
static void bcm7120_l2_intc_irq_handle(unsigned int irq, struct irq_desc *desc)
{
struct bcm7120_l2_intc_data *b = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned int idx;
chained_irq_enter(chip, desc);
for (idx = 0; idx < b->n_words; idx++) {
int base = idx * IRQS_PER_WORD;
struct irq_chip_generic *gc =
irq_get_domain_generic_chip(b->domain, base);
unsigned long pending;
int hwirq;
irq_gc_lock(gc);
pending = irq_reg_readl(gc, b->stat_offset[idx]) &
gc->mask_cache;
irq_gc_unlock(gc);
for_each_set_bit(hwirq, &pending, IRQS_PER_WORD) {
generic_handle_irq(irq_find_mapping(b->domain,
base + hwirq));
}
}
chained_irq_exit(chip, desc);
}
static void bcm7120_l2_intc_suspend(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = irq_data_get_chip_type(d);
struct bcm7120_l2_intc_data *b = gc->private;
irq_gc_lock(gc);
if (b->can_wake)
irq_reg_writel(gc, gc->mask_cache | gc->wake_active,
ct->regs.mask);
irq_gc_unlock(gc);
}
static void bcm7120_l2_intc_resume(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = irq_data_get_chip_type(d);
/* Restore the saved mask */
irq_gc_lock(gc);
irq_reg_writel(gc, gc->mask_cache, ct->regs.mask);
irq_gc_unlock(gc);
}
static int bcm7120_l2_intc_init_one(struct device_node *dn,
struct bcm7120_l2_intc_data *data,
int irq)
{
int parent_irq;
unsigned int idx;
parent_irq = irq_of_parse_and_map(dn, irq);
if (!parent_irq) {
pr_err("failed to map interrupt %d\n", irq);
return -EINVAL;
}
/* For multiple parent IRQs with multiple words, this looks like:
* <irq0_w0 irq0_w1 irq1_w0 irq1_w1 ...>
*/
for (idx = 0; idx < data->n_words; idx++)
data->irq_map_mask[idx] |=
be32_to_cpup(data->map_mask_prop +
irq * data->n_words + idx);
irq_set_handler_data(parent_irq, data);
irq_set_chained_handler(parent_irq, bcm7120_l2_intc_irq_handle);
return 0;
}
static int __init bcm7120_l2_intc_iomap_7120(struct device_node *dn,
struct bcm7120_l2_intc_data *data)
{
int ret;
data->map_base[0] = of_iomap(dn, 0);
if (!data->map_base[0]) {
pr_err("unable to map registers\n");
return -ENOMEM;
}
data->pair_base[0] = data->map_base[0];
data->en_offset[0] = IRQEN;
data->stat_offset[0] = IRQSTAT;
data->n_words = 1;
ret = of_property_read_u32_array(dn, "brcm,int-fwd-mask",
data->irq_fwd_mask, data->n_words);
if (ret != 0 && ret != -EINVAL) {
/* property exists but has the wrong number of words */
pr_err("invalid brcm,int-fwd-mask property\n");
return -EINVAL;
}
data->map_mask_prop = of_get_property(dn, "brcm,int-map-mask", &ret);
if (!data->map_mask_prop ||
(ret != (sizeof(__be32) * data->num_parent_irqs * data->n_words))) {
pr_err("invalid brcm,int-map-mask property\n");
return -EINVAL;
}
return 0;
}
int __init bcm7120_l2_intc_probe(struct device_node *dn,
struct device_node *parent,
int (*iomap_regs_fn)(struct device_node *,
struct bcm7120_l2_intc_data *),
const char *intc_name)
{
unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
struct bcm7120_l2_intc_data *data;
struct irq_chip_generic *gc;
struct irq_chip_type *ct;
int ret = 0;
unsigned int idx, irq, flags;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->num_parent_irqs = of_irq_count(dn);
if (data->num_parent_irqs <= 0) {
pr_err("invalid number of parent interrupts\n");
ret = -ENOMEM;
goto out_unmap;
}
ret = iomap_regs_fn(dn, data);
if (ret < 0)
goto out_unmap;
for (idx = 0; idx < data->n_words; idx++) {
__raw_writel(data->irq_fwd_mask[idx],
data->pair_base[idx] +
data->en_offset[idx]);
}
for (irq = 0; irq < data->num_parent_irqs; irq++) {
ret = bcm7120_l2_intc_init_one(dn, data, irq);
if (ret)
goto out_unmap;
}
data->domain = irq_domain_add_linear(dn, IRQS_PER_WORD * data->n_words,
&irq_generic_chip_ops, NULL);
if (!data->domain) {
ret = -ENOMEM;
goto out_unmap;
}
/* MIPS chips strapped for BE will automagically configure the
* peripheral registers for CPU-native byte order.
*/
flags = IRQ_GC_INIT_MASK_CACHE;
if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
flags |= IRQ_GC_BE_IO;
ret = irq_alloc_domain_generic_chips(data->domain, IRQS_PER_WORD, 1,
dn->full_name, handle_level_irq, clr, 0, flags);
if (ret) {
pr_err("failed to allocate generic irq chip\n");
goto out_free_domain;
}
if (of_property_read_bool(dn, "brcm,irq-can-wake"))
data->can_wake = true;
for (idx = 0; idx < data->n_words; idx++) {
irq = idx * IRQS_PER_WORD;
gc = irq_get_domain_generic_chip(data->domain, irq);
gc->unused = 0xffffffff & ~data->irq_map_mask[idx];
gc->private = data;
ct = gc->chip_types;
gc->reg_base = data->pair_base[idx];
ct->regs.mask = data->en_offset[idx];
ct->chip.irq_mask = irq_gc_mask_clr_bit;
ct->chip.irq_unmask = irq_gc_mask_set_bit;
ct->chip.irq_ack = irq_gc_noop;
ct->chip.irq_suspend = bcm7120_l2_intc_suspend;
ct->chip.irq_resume = bcm7120_l2_intc_resume;
if (data->can_wake) {
/* This IRQ chip can wake the system, set all
* relevant child interupts in wake_enabled mask
*/
gc->wake_enabled = 0xffffffff;
gc->wake_enabled &= ~gc->unused;
ct->chip.irq_set_wake = irq_gc_set_wake;
}
}
pr_info("registered %s intc (mem: 0x%p, parent IRQ(s): %d)\n",
intc_name, data->map_base[0], data->num_parent_irqs);
return 0;
out_free_domain:
irq_domain_remove(data->domain);
out_unmap:
for (idx = 0; idx < MAX_MAPPINGS; idx++) {
if (data->map_base[idx])
iounmap(data->map_base[idx]);
}
kfree(data);
return ret;
}
int __init bcm7120_l2_intc_probe_7120(struct device_node *dn,
struct device_node *parent)
{
return bcm7120_l2_intc_probe(dn, parent, bcm7120_l2_intc_iomap_7120,
"BCM7120 L2");
}
IRQCHIP_DECLARE(bcm7120_l2_intc, "brcm,bcm7120-l2-intc",
bcm7120_l2_intc_probe_7120);