irq-keystone.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Texas Instruments Keystone IRQ controller IP driver
  4 *
  5 * Copyright (C) 2014 Texas Instruments, Inc.
  6 * Author: Sajesh Kumar Saran <sajesh@ti.com>
  7 *	   Grygorii Strashko <grygorii.strashko@ti.com>
  8 */
  9
 10#include <linux/irq.h>
 11#include <linux/bitops.h>
 12#include <linux/module.h>
 13#include <linux/moduleparam.h>
 14#include <linux/interrupt.h>
 15#include <linux/irqdomain.h>
 16#include <linux/irqchip.h>
 17#include <linux/of.h>
 18#include <linux/platform_device.h>
 19#include <linux/mfd/syscon.h>
 20#include <linux/regmap.h>
 21
 22/* The source ID bits start from 4 to 31 (total 28 bits)*/
 23#define BIT_OFS			4
 24#define KEYSTONE_N_IRQ		(32 - BIT_OFS)
 25
 26struct keystone_irq_device {
 27	struct device		*dev;
 28	struct irq_chip		 chip;
 29	u32			 mask;
 30	int			 irq;
 31	struct irq_domain	*irqd;
 32	struct regmap		*devctrl_regs;
 33	u32			devctrl_offset;
 34	raw_spinlock_t		wa_lock;
 35};
 36
 37static inline u32 keystone_irq_readl(struct keystone_irq_device *kirq)
 38{
 39	int ret;
 40	u32 val = 0;
 41
 42	ret = regmap_read(kirq->devctrl_regs, kirq->devctrl_offset, &val);
 43	if (ret < 0)
 44		dev_dbg(kirq->dev, "irq read failed ret(%d)\n", ret);
 45	return val;
 46}
 47
 48static inline void
 49keystone_irq_writel(struct keystone_irq_device *kirq, u32 value)
 50{
 51	int ret;
 52
 53	ret = regmap_write(kirq->devctrl_regs, kirq->devctrl_offset, value);
 54	if (ret < 0)
 55		dev_dbg(kirq->dev, "irq write failed ret(%d)\n", ret);
 56}
 57
 58static void keystone_irq_setmask(struct irq_data *d)
 59{
 60	struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
 61
 62	kirq->mask |= BIT(d->hwirq);
 63	dev_dbg(kirq->dev, "mask %lu [%x]\n", d->hwirq, kirq->mask);
 64}
 65
 66static void keystone_irq_unmask(struct irq_data *d)
 67{
 68	struct keystone_irq_device *kirq = irq_data_get_irq_chip_data(d);
 69
 70	kirq->mask &= ~BIT(d->hwirq);
 71	dev_dbg(kirq->dev, "unmask %lu [%x]\n", d->hwirq, kirq->mask);
 72}
 73
 74static void keystone_irq_ack(struct irq_data *d)
 75{
 76	/* nothing to do here */
 77}
 78
 79static irqreturn_t keystone_irq_handler(int irq, void *keystone_irq)
 80{
 81	struct keystone_irq_device *kirq = keystone_irq;
 82	unsigned long wa_lock_flags;
 83	unsigned long pending;
 84	int src, err;
 85
 86	dev_dbg(kirq->dev, "start irq %d\n", irq);
 87
 88	pending = keystone_irq_readl(kirq);
 89	keystone_irq_writel(kirq, pending);
 90
 91	dev_dbg(kirq->dev, "pending 0x%lx, mask 0x%x\n", pending, kirq->mask);
 92
 93	pending = (pending >> BIT_OFS) & ~kirq->mask;
 94
 95	dev_dbg(kirq->dev, "pending after mask 0x%lx\n", pending);
 96
 97	for (src = 0; src < KEYSTONE_N_IRQ; src++) {
 98		if (BIT(src) & pending) {
 99			raw_spin_lock_irqsave(&kirq->wa_lock, wa_lock_flags);
100			err = generic_handle_domain_irq(kirq->irqd, src);
101			raw_spin_unlock_irqrestore(&kirq->wa_lock,
102						   wa_lock_flags);
103
104			if (err)
105				dev_warn_ratelimited(kirq->dev, "spurious irq detected hwirq %d\n",
106						     src);
107		}
108	}
109
110	dev_dbg(kirq->dev, "end irq %d\n", irq);
111	return IRQ_HANDLED;
112}
113
114static int keystone_irq_map(struct irq_domain *h, unsigned int virq,
115				irq_hw_number_t hw)
116{
117	struct keystone_irq_device *kirq = h->host_data;
118
119	irq_set_chip_data(virq, kirq);
120	irq_set_chip_and_handler(virq, &kirq->chip, handle_level_irq);
121	irq_set_probe(virq);
122	return 0;
123}
124
125static const struct irq_domain_ops keystone_irq_ops = {
126	.map	= keystone_irq_map,
127	.xlate	= irq_domain_xlate_onecell,
128};
129
130static int keystone_irq_probe(struct platform_device *pdev)
131{
132	struct device *dev = &pdev->dev;
133	struct device_node *np = dev->of_node;
134	struct keystone_irq_device *kirq;
135	int ret;
136
137	if (np == NULL)
138		return -EINVAL;
139
140	kirq = devm_kzalloc(dev, sizeof(*kirq), GFP_KERNEL);
141	if (!kirq)
142		return -ENOMEM;
143
144	kirq->devctrl_regs = syscon_regmap_lookup_by_phandle_args(np, "ti,syscon-dev",
145								  1, &kirq->devctrl_offset);
146	if (IS_ERR(kirq->devctrl_regs))
147		return PTR_ERR(kirq->devctrl_regs);
148
149	kirq->irq = platform_get_irq(pdev, 0);
150	if (kirq->irq < 0)
151		return kirq->irq;
152
153	kirq->dev = dev;
154	kirq->mask = ~0x0;
155	kirq->chip.name		= "keystone-irq";
156	kirq->chip.irq_ack	= keystone_irq_ack;
157	kirq->chip.irq_mask	= keystone_irq_setmask;
158	kirq->chip.irq_unmask	= keystone_irq_unmask;
159
160	kirq->irqd = irq_domain_create_linear(dev_fwnode(dev), KEYSTONE_N_IRQ, &keystone_irq_ops,
161					      kirq);
162	if (!kirq->irqd) {
163		dev_err(dev, "IRQ domain registration failed\n");
164		return -ENODEV;
165	}
166
167	raw_spin_lock_init(&kirq->wa_lock);
168
169	platform_set_drvdata(pdev, kirq);
170
171	ret = request_irq(kirq->irq, keystone_irq_handler,
172			  0, dev_name(dev), kirq);
173	if (ret) {
174		irq_domain_remove(kirq->irqd);
175		return ret;
176	}
177
178	/* clear all source bits */
179	keystone_irq_writel(kirq, ~0x0);
180
181	dev_info(dev, "irqchip registered, nr_irqs %u\n", KEYSTONE_N_IRQ);
182
183	return 0;
184}
185
186static void keystone_irq_remove(struct platform_device *pdev)
187{
188	struct keystone_irq_device *kirq = platform_get_drvdata(pdev);
189	int hwirq;
190
191	free_irq(kirq->irq, kirq);
192
193	for (hwirq = 0; hwirq < KEYSTONE_N_IRQ; hwirq++)
194		irq_dispose_mapping(irq_find_mapping(kirq->irqd, hwirq));
195
196	irq_domain_remove(kirq->irqd);
197}
198
199static const struct of_device_id keystone_irq_dt_ids[] = {
200	{ .compatible = "ti,keystone-irq", },
201	{},
202};
203MODULE_DEVICE_TABLE(of, keystone_irq_dt_ids);
204
205static struct platform_driver keystone_irq_device_driver = {
206	.probe		= keystone_irq_probe,
207	.remove		= keystone_irq_remove,
208	.driver		= {
209		.name	= "keystone_irq",
210		.of_match_table	= of_match_ptr(keystone_irq_dt_ids),
211	}
212};
213
214module_platform_driver(keystone_irq_device_driver);
215
216MODULE_AUTHOR("Texas Instruments");
217MODULE_AUTHOR("Sajesh Kumar Saran");
218MODULE_AUTHOR("Grygorii Strashko");
219MODULE_DESCRIPTION("Keystone IRQ chip");
220MODULE_LICENSE("GPL v2");