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
26 struct 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
keystone_irq_readl(struct keystone_irq_device * kirq)37 static 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
48 static inline void
keystone_irq_writel(struct keystone_irq_device * kirq,u32 value)49 keystone_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
keystone_irq_setmask(struct irq_data * d)58 static 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
keystone_irq_unmask(struct irq_data * d)66 static 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
keystone_irq_ack(struct irq_data * d)74 static void keystone_irq_ack(struct irq_data *d)
75 {
76 /* nothing to do here */
77 }
78
keystone_irq_handler(int irq,void * keystone_irq)79 static 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
keystone_irq_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)114 static 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
125 static const struct irq_domain_ops keystone_irq_ops = {
126 .map = keystone_irq_map,
127 .xlate = irq_domain_xlate_onecell,
128 };
129
keystone_irq_probe(struct platform_device * pdev)130 static 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 =
145 syscon_regmap_lookup_by_phandle(np, "ti,syscon-dev");
146 if (IS_ERR(kirq->devctrl_regs))
147 return PTR_ERR(kirq->devctrl_regs);
148
149 ret = of_property_read_u32_index(np, "ti,syscon-dev", 1,
150 &kirq->devctrl_offset);
151 if (ret) {
152 dev_err(dev, "couldn't read the devctrl_offset offset!\n");
153 return ret;
154 }
155
156 kirq->irq = platform_get_irq(pdev, 0);
157 if (kirq->irq < 0)
158 return kirq->irq;
159
160 kirq->dev = dev;
161 kirq->mask = ~0x0;
162 kirq->chip.name = "keystone-irq";
163 kirq->chip.irq_ack = keystone_irq_ack;
164 kirq->chip.irq_mask = keystone_irq_setmask;
165 kirq->chip.irq_unmask = keystone_irq_unmask;
166
167 kirq->irqd = irq_domain_add_linear(np, KEYSTONE_N_IRQ,
168 &keystone_irq_ops, kirq);
169 if (!kirq->irqd) {
170 dev_err(dev, "IRQ domain registration failed\n");
171 return -ENODEV;
172 }
173
174 raw_spin_lock_init(&kirq->wa_lock);
175
176 platform_set_drvdata(pdev, kirq);
177
178 ret = request_irq(kirq->irq, keystone_irq_handler,
179 0, dev_name(dev), kirq);
180 if (ret) {
181 irq_domain_remove(kirq->irqd);
182 return ret;
183 }
184
185 /* clear all source bits */
186 keystone_irq_writel(kirq, ~0x0);
187
188 dev_info(dev, "irqchip registered, nr_irqs %u\n", KEYSTONE_N_IRQ);
189
190 return 0;
191 }
192
keystone_irq_remove(struct platform_device * pdev)193 static void keystone_irq_remove(struct platform_device *pdev)
194 {
195 struct keystone_irq_device *kirq = platform_get_drvdata(pdev);
196 int hwirq;
197
198 free_irq(kirq->irq, kirq);
199
200 for (hwirq = 0; hwirq < KEYSTONE_N_IRQ; hwirq++)
201 irq_dispose_mapping(irq_find_mapping(kirq->irqd, hwirq));
202
203 irq_domain_remove(kirq->irqd);
204 }
205
206 static const struct of_device_id keystone_irq_dt_ids[] = {
207 { .compatible = "ti,keystone-irq", },
208 {},
209 };
210 MODULE_DEVICE_TABLE(of, keystone_irq_dt_ids);
211
212 static struct platform_driver keystone_irq_device_driver = {
213 .probe = keystone_irq_probe,
214 .remove_new = keystone_irq_remove,
215 .driver = {
216 .name = "keystone_irq",
217 .of_match_table = of_match_ptr(keystone_irq_dt_ids),
218 }
219 };
220
221 module_platform_driver(keystone_irq_device_driver);
222
223 MODULE_AUTHOR("Texas Instruments");
224 MODULE_AUTHOR("Sajesh Kumar Saran");
225 MODULE_AUTHOR("Grygorii Strashko");
226 MODULE_DESCRIPTION("Keystone IRQ chip");
227 MODULE_LICENSE("GPL v2");
228