/*
* Copyright (C) 2016 ARM Limited, All Rights Reserved.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/irqchip.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqchip/irq-partition-percpu.h>
#include <linux/irqdomain.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
struct partition_desc {
int nr_parts;
struct partition_affinity *parts;
struct irq_domain *domain;
struct irq_desc *chained_desc;
unsigned long *bitmap;
struct irq_domain_ops ops;
};
static bool partition_check_cpu(struct partition_desc *part,
unsigned int cpu, unsigned int hwirq)
{
return cpumask_test_cpu(cpu, &part->parts[hwirq].mask);
}
static void partition_irq_mask(struct irq_data *d)
{
struct partition_desc *part = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
chip->irq_mask)
chip->irq_mask(data);
}
static void partition_irq_unmask(struct irq_data *d)
{
struct partition_desc *part = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
chip->irq_unmask)
chip->irq_unmask(data);
}
static int partition_irq_set_irqchip_state(struct irq_data *d,
enum irqchip_irq_state which,
bool val)
{
struct partition_desc *part = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
chip->irq_set_irqchip_state)
return chip->irq_set_irqchip_state(data, which, val);
return -EINVAL;
}
static int partition_irq_get_irqchip_state(struct irq_data *d,
enum irqchip_irq_state which,
bool *val)
{
struct partition_desc *part = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
chip->irq_get_irqchip_state)
return chip->irq_get_irqchip_state(data, which, val);
return -EINVAL;
}
static int partition_irq_set_type(struct irq_data *d, unsigned int type)
{
struct partition_desc *part = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
if (chip->irq_set_type)
return chip->irq_set_type(data, type);
return -EINVAL;
}
static void partition_irq_print_chip(struct irq_data *d, struct seq_file *p)
{
struct partition_desc *part = irq_data_get_irq_chip_data(d);
struct irq_chip *chip = irq_desc_get_chip(part->chained_desc);
struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
seq_printf(p, " %5s-%lu", chip->name, data->hwirq);
}
static struct irq_chip partition_irq_chip = {
.irq_mask = partition_irq_mask,
.irq_unmask = partition_irq_unmask,
.irq_set_type = partition_irq_set_type,
.irq_get_irqchip_state = partition_irq_get_irqchip_state,
.irq_set_irqchip_state = partition_irq_set_irqchip_state,
.irq_print_chip = partition_irq_print_chip,
};
static void partition_handle_irq(struct irq_desc *desc)
{
struct partition_desc *part = irq_desc_get_handler_data(desc);
struct irq_chip *chip = irq_desc_get_chip(desc);
int cpu = smp_processor_id();
int hwirq;
chained_irq_enter(chip, desc);
for_each_set_bit(hwirq, part->bitmap, part->nr_parts) {
if (partition_check_cpu(part, cpu, hwirq))
break;
}
if (unlikely(hwirq == part->nr_parts)) {
handle_bad_irq(desc);
} else {
unsigned int irq;
irq = irq_find_mapping(part->domain, hwirq);
generic_handle_irq(irq);
}
chained_irq_exit(chip, desc);
}
static int partition_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *arg)
{
int ret;
irq_hw_number_t hwirq;
unsigned int type;
struct irq_fwspec *fwspec = arg;
struct partition_desc *part;
BUG_ON(nr_irqs != 1);
ret = domain->ops->translate(domain, fwspec, &hwirq, &type);
if (ret)
return ret;
part = domain->host_data;
set_bit(hwirq, part->bitmap);
irq_set_chained_handler_and_data(irq_desc_get_irq(part->chained_desc),
partition_handle_irq, part);
irq_set_percpu_devid_partition(virq, &part->parts[hwirq].mask);
irq_domain_set_info(domain, virq, hwirq, &partition_irq_chip, part,
handle_percpu_devid_irq, NULL, NULL);
irq_set_status_flags(virq, IRQ_NOAUTOEN);
return 0;
}
static void partition_domain_free(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs)
{
struct irq_data *d;
BUG_ON(nr_irqs != 1);
d = irq_domain_get_irq_data(domain, virq);
irq_set_handler(virq, NULL);
irq_domain_reset_irq_data(d);
}
int partition_translate_id(struct partition_desc *desc, void *partition_id)
{
struct partition_affinity *part = NULL;
int i;
for (i = 0; i < desc->nr_parts; i++) {
if (desc->parts[i].partition_id == partition_id) {
part = &desc->parts[i];
break;
}
}
if (WARN_ON(!part)) {
pr_err("Failed to find partition\n");
return -EINVAL;
}
return i;
}
struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
struct partition_affinity *parts,
int nr_parts,
int chained_irq,
const struct irq_domain_ops *ops)
{
struct partition_desc *desc;
struct irq_domain *d;
BUG_ON(!ops->select || !ops->translate);
desc = kzalloc(sizeof(*desc), GFP_KERNEL);
if (!desc)
return NULL;
desc->ops = *ops;
desc->ops.free = partition_domain_free;
desc->ops.alloc = partition_domain_alloc;
d = irq_domain_create_linear(fwnode, nr_parts, &desc->ops, desc);
if (!d)
goto out;
desc->domain = d;
desc->bitmap = kzalloc(sizeof(long) * BITS_TO_LONGS(nr_parts),
GFP_KERNEL);
if (WARN_ON(!desc->bitmap))
goto out;
desc->chained_desc = irq_to_desc(chained_irq);
desc->nr_parts = nr_parts;
desc->parts = parts;
return desc;
out:
if (d)
irq_domain_remove(d);
kfree(desc);
return NULL;
}
struct irq_domain *partition_get_domain(struct partition_desc *dsc)
{
if (dsc)
return dsc->domain;
return NULL;
}
