linux/drivers/irqchip/irq-meson-gpio.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2015 Endless Mobile, Inc.
* Author: Carlo Caione <carlo@endlessm.com>
* Copyright (c) 2016 BayLibre, SAS.
* Author: Jerome Brunet <jbrunet@baylibre.com>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/io.h>
#include <linux/module.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/irqchip.h>
#include <linux/of.h>
#include <linux/of_address.h>
#define NUM_CHANNEL 8
#define MAX_INPUT_MUX 256
#define REG_EDGE_POL 0x00
#define REG_PIN_03_SEL 0x04
#define REG_PIN_47_SEL 0x08
#define REG_FILTER_SEL 0x0c
/*
* Note: The S905X3 datasheet reports that BOTH_EDGE is controlled by
* bits 24 to 31. Tests on the actual HW show that these bits are
* stuck at 0. Bits 8 to 15 are responsive and have the expected
* effect.
*/
#define REG_EDGE_POL_EDGE(x) BIT(x)
#define REG_EDGE_POL_LOW(x) BIT(16 + (x))
#define REG_BOTH_EDGE(x) BIT(8 + (x))
#define REG_EDGE_POL_MASK(x) ( \
REG_EDGE_POL_EDGE(x) | \
REG_EDGE_POL_LOW(x) | \
REG_BOTH_EDGE(x))
#define REG_PIN_SEL_SHIFT(x) (((x) % 4) * 8)
#define REG_FILTER_SEL_SHIFT(x) ((x) * 4)
struct meson_gpio_irq_params {
unsigned int nr_hwirq;
bool support_edge_both;
};
static const struct meson_gpio_irq_params meson8_params = {
.nr_hwirq = 134,
};
static const struct meson_gpio_irq_params meson8b_params = {
.nr_hwirq = 119,
};
static const struct meson_gpio_irq_params gxbb_params = {
.nr_hwirq = 133,
};
static const struct meson_gpio_irq_params gxl_params = {
.nr_hwirq = 110,
};
static const struct meson_gpio_irq_params axg_params = {
.nr_hwirq = 100,
};
static const struct meson_gpio_irq_params sm1_params = {
.nr_hwirq = 100,
.support_edge_both = true,
};
static const struct of_device_id meson_irq_gpio_matches[] = {
{ .compatible = "amlogic,meson8-gpio-intc", .data = &meson8_params },
{ .compatible = "amlogic,meson8b-gpio-intc", .data = &meson8b_params },
{ .compatible = "amlogic,meson-gxbb-gpio-intc", .data = &gxbb_params },
{ .compatible = "amlogic,meson-gxl-gpio-intc", .data = &gxl_params },
{ .compatible = "amlogic,meson-axg-gpio-intc", .data = &axg_params },
{ .compatible = "amlogic,meson-g12a-gpio-intc", .data = &axg_params },
{ .compatible = "amlogic,meson-sm1-gpio-intc", .data = &sm1_params },
{ }
};
struct meson_gpio_irq_controller {
const struct meson_gpio_irq_params *params;
void __iomem *base;
u32 channel_irqs[NUM_CHANNEL];
DECLARE_BITMAP(channel_map, NUM_CHANNEL);
spinlock_t lock;
};
static void meson_gpio_irq_update_bits(struct meson_gpio_irq_controller *ctl,
unsigned int reg, u32 mask, u32 val)
{
u32 tmp;
tmp = readl_relaxed(ctl->base + reg);
tmp &= ~mask;
tmp |= val;
writel_relaxed(tmp, ctl->base + reg);
}
static unsigned int meson_gpio_irq_channel_to_reg(unsigned int channel)
{
return (channel < 4) ? REG_PIN_03_SEL : REG_PIN_47_SEL;
}
static int
meson_gpio_irq_request_channel(struct meson_gpio_irq_controller *ctl,
unsigned long hwirq,
u32 **channel_hwirq)
{
unsigned int reg, idx;
spin_lock(&ctl->lock);
/* Find a free channel */
idx = find_first_zero_bit(ctl->channel_map, NUM_CHANNEL);
if (idx >= NUM_CHANNEL) {
spin_unlock(&ctl->lock);
pr_err("No channel available\n");
return -ENOSPC;
}
/* Mark the channel as used */
set_bit(idx, ctl->channel_map);
/*
* Setup the mux of the channel to route the signal of the pad
* to the appropriate input of the GIC
*/
reg = meson_gpio_irq_channel_to_reg(idx);
meson_gpio_irq_update_bits(ctl, reg,
0xff << REG_PIN_SEL_SHIFT(idx),
hwirq << REG_PIN_SEL_SHIFT(idx));
/*
* Get the hwirq number assigned to this channel through
* a pointer the channel_irq table. The added benifit of this
* method is that we can also retrieve the channel index with
* it, using the table base.
*/
*channel_hwirq = &(ctl->channel_irqs[idx]);
spin_unlock(&ctl->lock);
pr_debug("hwirq %lu assigned to channel %d - irq %u\n",
hwirq, idx, **channel_hwirq);
return 0;
}
static unsigned int
meson_gpio_irq_get_channel_idx(struct meson_gpio_irq_controller *ctl,
u32 *channel_hwirq)
{
return channel_hwirq - ctl->channel_irqs;
}
static void
meson_gpio_irq_release_channel(struct meson_gpio_irq_controller *ctl,
u32 *channel_hwirq)
{
unsigned int idx;
idx = meson_gpio_irq_get_channel_idx(ctl, channel_hwirq);
clear_bit(idx, ctl->channel_map);
}
static int meson_gpio_irq_type_setup(struct meson_gpio_irq_controller *ctl,
unsigned int type,
u32 *channel_hwirq)
{
u32 val = 0;
unsigned int idx;
idx = meson_gpio_irq_get_channel_idx(ctl, channel_hwirq);
/*
* The controller has a filter block to operate in either LEVEL or
* EDGE mode, then signal is sent to the GIC. To enable LEVEL_LOW and
* EDGE_FALLING support (which the GIC does not support), the filter
* block is also able to invert the input signal it gets before
* providing it to the GIC.
*/
type &= IRQ_TYPE_SENSE_MASK;
/*
* New controller support EDGE_BOTH trigger. This setting takes
* precedence over the other edge/polarity settings
*/
if (type == IRQ_TYPE_EDGE_BOTH) {
if (!ctl->params->support_edge_both)
return -EINVAL;
val |= REG_BOTH_EDGE(idx);
} else {
if (type & (IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING))
val |= REG_EDGE_POL_EDGE(idx);
if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_EDGE_FALLING))
val |= REG_EDGE_POL_LOW(idx);
}
spin_lock(&ctl->lock);
meson_gpio_irq_update_bits(ctl, REG_EDGE_POL,
REG_EDGE_POL_MASK(idx), val);
spin_unlock(&ctl->lock);
return 0;
}
static unsigned int meson_gpio_irq_type_output(unsigned int type)
{
unsigned int sense = type & IRQ_TYPE_SENSE_MASK;
type &= ~IRQ_TYPE_SENSE_MASK;
/*
* The polarity of the signal provided to the GIC should always
* be high.
*/
if (sense & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
type |= IRQ_TYPE_LEVEL_HIGH;
else
type |= IRQ_TYPE_EDGE_RISING;
return type;
}
static int meson_gpio_irq_set_type(struct irq_data *data, unsigned int type)
{
struct meson_gpio_irq_controller *ctl = data->domain->host_data;
u32 *channel_hwirq = irq_data_get_irq_chip_data(data);
int ret;
ret = meson_gpio_irq_type_setup(ctl, type, channel_hwirq);
if (ret)
return ret;
return irq_chip_set_type_parent(data,
meson_gpio_irq_type_output(type));
}
static struct irq_chip meson_gpio_irq_chip = {
.name = "meson-gpio-irqchip",
.irq_mask = irq_chip_mask_parent,
.irq_unmask = irq_chip_unmask_parent,
.irq_eoi = irq_chip_eoi_parent,
.irq_set_type = meson_gpio_irq_set_type,
.irq_retrigger = irq_chip_retrigger_hierarchy,
#ifdef CONFIG_SMP
.irq_set_affinity = irq_chip_set_affinity_parent,
#endif
.flags = IRQCHIP_SET_TYPE_MASKED,
};
static int meson_gpio_irq_domain_translate(struct irq_domain *domain,
struct irq_fwspec *fwspec,
unsigned long *hwirq,
unsigned int *type)
{
if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
*hwirq = fwspec->param[0];
*type = fwspec->param[1];
return 0;
}
return -EINVAL;
}
static int meson_gpio_irq_allocate_gic_irq(struct irq_domain *domain,
unsigned int virq,
u32 hwirq,
unsigned int type)
{
struct irq_fwspec fwspec;
fwspec.fwnode = domain->parent->fwnode;
fwspec.param_count = 3;
fwspec.param[0] = 0; /* SPI */
fwspec.param[1] = hwirq;
fwspec.param[2] = meson_gpio_irq_type_output(type);
return irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec);
}
static int meson_gpio_irq_domain_alloc(struct irq_domain *domain,
unsigned int virq,
unsigned int nr_irqs,
void *data)
{
struct irq_fwspec *fwspec = data;
struct meson_gpio_irq_controller *ctl = domain->host_data;
unsigned long hwirq;
u32 *channel_hwirq;
unsigned int type;
int ret;
if (WARN_ON(nr_irqs != 1))
return -EINVAL;
ret = meson_gpio_irq_domain_translate(domain, fwspec, &hwirq, &type);
if (ret)
return ret;
ret = meson_gpio_irq_request_channel(ctl, hwirq, &channel_hwirq);
if (ret)
return ret;
ret = meson_gpio_irq_allocate_gic_irq(domain, virq,
*channel_hwirq, type);
if (ret < 0) {
pr_err("failed to allocate gic irq %u\n", *channel_hwirq);
meson_gpio_irq_release_channel(ctl, channel_hwirq);
return ret;
}
irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
&meson_gpio_irq_chip, channel_hwirq);
return 0;
}
static void meson_gpio_irq_domain_free(struct irq_domain *domain,
unsigned int virq,
unsigned int nr_irqs)
{
struct meson_gpio_irq_controller *ctl = domain->host_data;
struct irq_data *irq_data;
u32 *channel_hwirq;
if (WARN_ON(nr_irqs != 1))
return;
irq_domain_free_irqs_parent(domain, virq, 1);
irq_data = irq_domain_get_irq_data(domain, virq);
channel_hwirq = irq_data_get_irq_chip_data(irq_data);
meson_gpio_irq_release_channel(ctl, channel_hwirq);
}
static const struct irq_domain_ops meson_gpio_irq_domain_ops = {
.alloc = meson_gpio_irq_domain_alloc,
.free = meson_gpio_irq_domain_free,
.translate = meson_gpio_irq_domain_translate,
};
static int __init meson_gpio_irq_parse_dt(struct device_node *node,
struct meson_gpio_irq_controller *ctl)
{
const struct of_device_id *match;
int ret;
match = of_match_node(meson_irq_gpio_matches, node);
if (!match)
return -ENODEV;
ctl->params = match->data;
ret = of_property_read_variable_u32_array(node,
"amlogic,channel-interrupts",
ctl->channel_irqs,
NUM_CHANNEL,
NUM_CHANNEL);
if (ret < 0) {
pr_err("can't get %d channel interrupts\n", NUM_CHANNEL);
return ret;
}
return 0;
}
static int __init meson_gpio_irq_of_init(struct device_node *node,
struct device_node *parent)
{
struct irq_domain *domain, *parent_domain;
struct meson_gpio_irq_controller *ctl;
int ret;
if (!parent) {
pr_err("missing parent interrupt node\n");
return -ENODEV;
}
parent_domain = irq_find_host(parent);
if (!parent_domain) {
pr_err("unable to obtain parent domain\n");
return -ENXIO;
}
ctl = kzalloc(sizeof(*ctl), GFP_KERNEL);
if (!ctl)
return -ENOMEM;
spin_lock_init(&ctl->lock);
ctl->base = of_iomap(node, 0);
if (!ctl->base) {
ret = -ENOMEM;
goto free_ctl;
}
ret = meson_gpio_irq_parse_dt(node, ctl);
if (ret)
goto free_channel_irqs;
domain = irq_domain_create_hierarchy(parent_domain, 0,
ctl->params->nr_hwirq,
of_node_to_fwnode(node),
&meson_gpio_irq_domain_ops,
ctl);
if (!domain) {
pr_err("failed to add domain\n");
ret = -ENODEV;
goto free_channel_irqs;
}
pr_info("%d to %d gpio interrupt mux initialized\n",
ctl->params->nr_hwirq, NUM_CHANNEL);
return 0;
free_channel_irqs:
iounmap(ctl->base);
free_ctl:
kfree(ctl);
return ret;
}
IRQCHIP_DECLARE(meson_gpio_intc, "amlogic,meson-gpio-intc",
meson_gpio_irq_of_init);