/*
* Copyright (C) 2015 Hisilicon Limited, All Rights Reserved.
* Author: Jun Ma <majun258@huawei.com>
* Author: Yun Wu <wuyun.wu@huawei.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/interrupt.h>
#include <linux/irqchip.h>
#include <linux/module.h>
#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
/* Interrupt numbers per mbigen node supported */
#define IRQS_PER_MBIGEN_NODE 128
/* 64 irqs (Pin0-pin63) are reserved for each mbigen chip */
#define RESERVED_IRQ_PER_MBIGEN_CHIP 64
/* The maximum IRQ pin number of mbigen chip(start from 0) */
#define MAXIMUM_IRQ_PIN_NUM 1407
/**
* In mbigen vector register
* bit[21:12]: event id value
* bit[11:0]: device id
*/
#define IRQ_EVENT_ID_SHIFT 12
#define IRQ_EVENT_ID_MASK 0x3ff
/* register range of each mbigen node */
#define MBIGEN_NODE_OFFSET 0x1000
/* offset of vector register in mbigen node */
#define REG_MBIGEN_VEC_OFFSET 0x200
/**
* struct mbigen_device - holds the information of mbigen device.
*
* @pdev: pointer to the platform device structure of mbigen chip.
* @base: mapped address of this mbigen chip.
*/
struct mbigen_device {
struct platform_device *pdev;
void __iomem *base;
};
static inline unsigned int get_mbigen_vec_reg(irq_hw_number_t hwirq)
{
unsigned int nid, pin;
hwirq -= RESERVED_IRQ_PER_MBIGEN_CHIP;
nid = hwirq / IRQS_PER_MBIGEN_NODE + 1;
pin = hwirq % IRQS_PER_MBIGEN_NODE;
return pin * 4 + nid * MBIGEN_NODE_OFFSET
+ REG_MBIGEN_VEC_OFFSET;
}
static struct irq_chip mbigen_irq_chip = {
.name = "mbigen-v2",
};
static void mbigen_write_msg(struct msi_desc *desc, struct msi_msg *msg)
{
struct irq_data *d = irq_get_irq_data(desc->irq);
void __iomem *base = d->chip_data;
u32 val;
base += get_mbigen_vec_reg(d->hwirq);
val = readl_relaxed(base);
val &= ~(IRQ_EVENT_ID_MASK << IRQ_EVENT_ID_SHIFT);
val |= (msg->data << IRQ_EVENT_ID_SHIFT);
/* The address of doorbell is encoded in mbigen register by default
* So,we don't need to program the doorbell address at here
*/
writel_relaxed(val, base);
}
static int mbigen_domain_translate(struct irq_domain *d,
struct irq_fwspec *fwspec,
unsigned long *hwirq,
unsigned int *type)
{
if (is_of_node(fwspec->fwnode)) {
if (fwspec->param_count != 2)
return -EINVAL;
if ((fwspec->param[0] > MAXIMUM_IRQ_PIN_NUM) ||
(fwspec->param[0] < RESERVED_IRQ_PER_MBIGEN_CHIP))
return -EINVAL;
else
*hwirq = fwspec->param[0];
/* If there is no valid irq type, just use the default type */
if ((fwspec->param[1] == IRQ_TYPE_EDGE_RISING) ||
(fwspec->param[1] == IRQ_TYPE_LEVEL_HIGH))
*type = fwspec->param[1];
else
return -EINVAL;
return 0;
}
return -EINVAL;
}
static int mbigen_irq_domain_alloc(struct irq_domain *domain,
unsigned int virq,
unsigned int nr_irqs,
void *args)
{
struct irq_fwspec *fwspec = args;
irq_hw_number_t hwirq;
unsigned int type;
struct mbigen_device *mgn_chip;
int i, err;
err = mbigen_domain_translate(domain, fwspec, &hwirq, &type);
if (err)
return err;
err = platform_msi_domain_alloc(domain, virq, nr_irqs);
if (err)
return err;
mgn_chip = platform_msi_get_host_data(domain);
for (i = 0; i < nr_irqs; i++)
irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
&mbigen_irq_chip, mgn_chip->base);
return 0;
}
static struct irq_domain_ops mbigen_domain_ops = {
.translate = mbigen_domain_translate,
.alloc = mbigen_irq_domain_alloc,
.free = irq_domain_free_irqs_common,
};
static int mbigen_device_probe(struct platform_device *pdev)
{
struct mbigen_device *mgn_chip;
struct resource *res;
struct irq_domain *domain;
u32 num_pins;
mgn_chip = devm_kzalloc(&pdev->dev, sizeof(*mgn_chip), GFP_KERNEL);
if (!mgn_chip)
return -ENOMEM;
mgn_chip->pdev = pdev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mgn_chip->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(mgn_chip->base))
return PTR_ERR(mgn_chip->base);
if (of_property_read_u32(pdev->dev.of_node, "num-pins", &num_pins) < 0) {
dev_err(&pdev->dev, "No num-pins property\n");
return -EINVAL;
}
domain = platform_msi_create_device_domain(&pdev->dev, num_pins,
mbigen_write_msg,
&mbigen_domain_ops,
mgn_chip);
if (!domain)
return -ENOMEM;
platform_set_drvdata(pdev, mgn_chip);
dev_info(&pdev->dev, "Allocated %d MSIs\n", num_pins);
return 0;
}
static const struct of_device_id mbigen_of_match[] = {
{ .compatible = "hisilicon,mbigen-v2" },
{ /* END */ }
};
MODULE_DEVICE_TABLE(of, mbigen_of_match);
static struct platform_driver mbigen_platform_driver = {
.driver = {
.name = "Hisilicon MBIGEN-V2",
.owner = THIS_MODULE,
.of_match_table = mbigen_of_match,
},
.probe = mbigen_device_probe,
};
module_platform_driver(mbigen_platform_driver);
MODULE_AUTHOR("Jun Ma <majun258@huawei.com>");
MODULE_AUTHOR("Yun Wu <wuyun.wu@huawei.com>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Hisilicon MBI Generator driver");
