1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright 2017 NXP
4 * Copyright (C) 2018 Pengutronix, Lucas Stach <kernel@pengutronix.de>
5 */
6
7#include <linux/clk.h>
8#include <linux/interrupt.h>
9#include <linux/irq.h>
10#include <linux/irqchip/chained_irq.h>
11#include <linux/irqdomain.h>
12#include <linux/kernel.h>
13#include <linux/of_irq.h>
14#include <linux/of_platform.h>
15#include <linux/spinlock.h>
16
17#define CTRL_STRIDE_OFF(_t, _r) (_t * 4 * _r)
18#define CHANCTRL 0x0
19#define CHANMASK(n, t) (CTRL_STRIDE_OFF(t, 0) + 0x4 * (n) + 0x4)
20#define CHANSET(n, t) (CTRL_STRIDE_OFF(t, 1) + 0x4 * (n) + 0x4)
21#define CHANSTATUS(n, t) (CTRL_STRIDE_OFF(t, 2) + 0x4 * (n) + 0x4)
22#define CHAN_MINTDIS(t) (CTRL_STRIDE_OFF(t, 3) + 0x4)
23#define CHAN_MASTRSTAT(t) (CTRL_STRIDE_OFF(t, 3) + 0x8)
24
25#define CHAN_MAX_OUTPUT_INT 0x8
26
27struct irqsteer_data {
28 void __iomem *regs;
29 struct clk *ipg_clk;
30 int irq[CHAN_MAX_OUTPUT_INT];
31 int irq_count;
32 raw_spinlock_t lock;
33 int reg_num;
34 int channel;
35 struct irq_domain *domain;
36 u32 *saved_reg;
37};
38
39static int imx_irqsteer_get_reg_index(struct irqsteer_data *data,
40 unsigned long irqnum)
41{
42 return (data->reg_num - irqnum / 32 - 1);
43}
44
45static void imx_irqsteer_irq_unmask(struct irq_data *d)
46{
47 struct irqsteer_data *data = d->chip_data;
48 int idx = imx_irqsteer_get_reg_index(data, d->hwirq);
49 unsigned long flags;
50 u32 val;
51
52 raw_spin_lock_irqsave(&data->lock, flags);
53 val = readl_relaxed(data->regs + CHANMASK(idx, data->reg_num));
54 val |= BIT(d->hwirq % 32);
55 writel_relaxed(val, data->regs + CHANMASK(idx, data->reg_num));
56 raw_spin_unlock_irqrestore(&data->lock, flags);
57}
58
59static void imx_irqsteer_irq_mask(struct irq_data *d)
60{
61 struct irqsteer_data *data = d->chip_data;
62 int idx = imx_irqsteer_get_reg_index(data, d->hwirq);
63 unsigned long flags;
64 u32 val;
65
66 raw_spin_lock_irqsave(&data->lock, flags);
67 val = readl_relaxed(data->regs + CHANMASK(idx, data->reg_num));
68 val &= ~BIT(d->hwirq % 32);
69 writel_relaxed(val, data->regs + CHANMASK(idx, data->reg_num));
70 raw_spin_unlock_irqrestore(&data->lock, flags);
71}
72
73static struct irq_chip imx_irqsteer_irq_chip = {
74 .name = "irqsteer",
75 .irq_mask = imx_irqsteer_irq_mask,
76 .irq_unmask = imx_irqsteer_irq_unmask,
77};
78
79static int imx_irqsteer_irq_map(struct irq_domain *h, unsigned int irq,
80 irq_hw_number_t hwirq)
81{
82 irq_set_status_flags(irq, IRQ_LEVEL);
83 irq_set_chip_data(irq, h->host_data);
84 irq_set_chip_and_handler(irq, &imx_irqsteer_irq_chip, handle_level_irq);
85
86 return 0;
87}
88
89static const struct irq_domain_ops imx_irqsteer_domain_ops = {
90 .map = imx_irqsteer_irq_map,
91 .xlate = irq_domain_xlate_onecell,
92};
93
94static int imx_irqsteer_get_hwirq_base(struct irqsteer_data *data, u32 irq)
95{
96 int i;
97
98 for (i = 0; i < data->irq_count; i++) {
99 if (data->irq[i] == irq)
100 return i * 64;
101 }
102
103 return -EINVAL;
104}
105
106static void imx_irqsteer_irq_handler(struct irq_desc *desc)
107{
108 struct irqsteer_data *data = irq_desc_get_handler_data(desc);
109 int hwirq;
110 int irq, i;
111
112 chained_irq_enter(irq_desc_get_chip(desc), desc);
113
114 irq = irq_desc_get_irq(desc);
115 hwirq = imx_irqsteer_get_hwirq_base(data, irq);
116 if (hwirq < 0) {
117 pr_warn("%s: unable to get hwirq base for irq %d\n",
118 __func__, irq);
119 return;
120 }
121
122 for (i = 0; i < 2; i++, hwirq += 32) {
123 int idx = imx_irqsteer_get_reg_index(data, hwirq);
124 unsigned long irqmap;
125 int pos, virq;
126
127 if (hwirq >= data->reg_num * 32)
128 break;
129
130 irqmap = readl_relaxed(data->regs +
131 CHANSTATUS(idx, data->reg_num));
132
133 for_each_set_bit(pos, &irqmap, 32) {
134 virq = irq_find_mapping(data->domain, pos + hwirq);
135 if (virq)
136 generic_handle_irq(virq);
137 }
138 }
139
140 chained_irq_exit(irq_desc_get_chip(desc), desc);
141}
142
143static int imx_irqsteer_probe(struct platform_device *pdev)
144{
145 struct device_node *np = pdev->dev.of_node;
146 struct irqsteer_data *data;
147 struct resource *res;
148 u32 irqs_num;
149 int i, ret;
150
151 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
152 if (!data)
153 return -ENOMEM;
154
155 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
156 data->regs = devm_ioremap_resource(&pdev->dev, res);
157 if (IS_ERR(data->regs)) {
158 dev_err(&pdev->dev, "failed to initialize reg\n");
159 return PTR_ERR(data->regs);
160 }
161
162 data->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
163 if (IS_ERR(data->ipg_clk)) {
164 ret = PTR_ERR(data->ipg_clk);
165 if (ret != -EPROBE_DEFER)
166 dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret);
167 return ret;
168 }
169
170 raw_spin_lock_init(&data->lock);
171
172 ret = of_property_read_u32(np, "fsl,num-irqs", &irqs_num);
173 if (ret)
174 return ret;
175 ret = of_property_read_u32(np, "fsl,channel", &data->channel);
176 if (ret)
177 return ret;
178
179 /*
180 * There is one output irq for each group of 64 inputs.
181 * One register bit map can represent 32 input interrupts.
182 */
183 data->irq_count = DIV_ROUND_UP(irqs_num, 64);
184 data->reg_num = irqs_num / 32;
185
186 if (IS_ENABLED(CONFIG_PM_SLEEP)) {
187 data->saved_reg = devm_kzalloc(&pdev->dev,
188 sizeof(u32) * data->reg_num,
189 GFP_KERNEL);
190 if (!data->saved_reg)
191 return -ENOMEM;
192 }
193
194 ret = clk_prepare_enable(data->ipg_clk);
195 if (ret) {
196 dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret);
197 return ret;
198 }
199
200 /* steer all IRQs into configured channel */
201 writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
202
203 data->domain = irq_domain_add_linear(np, data->reg_num * 32,
204 &imx_irqsteer_domain_ops, data);
205 if (!data->domain) {
206 dev_err(&pdev->dev, "failed to create IRQ domain\n");
207 ret = -ENOMEM;
208 goto out;
209 }
210
211 if (!data->irq_count || data->irq_count > CHAN_MAX_OUTPUT_INT) {
212 ret = -EINVAL;
213 goto out;
214 }
215
216 for (i = 0; i < data->irq_count; i++) {
217 data->irq[i] = irq_of_parse_and_map(np, i);
218 if (!data->irq[i]) {
219 ret = -EINVAL;
220 goto out;
221 }
222
223 irq_set_chained_handler_and_data(data->irq[i],
224 imx_irqsteer_irq_handler,
225 data);
226 }
227
228 platform_set_drvdata(pdev, data);
229
230 return 0;
231out:
232 clk_disable_unprepare(data->ipg_clk);
233 return ret;
234}
235
236static int imx_irqsteer_remove(struct platform_device *pdev)
237{
238 struct irqsteer_data *irqsteer_data = platform_get_drvdata(pdev);
239 int i;
240
241 for (i = 0; i < irqsteer_data->irq_count; i++)
242 irq_set_chained_handler_and_data(irqsteer_data->irq[i],
243 NULL, NULL);
244
245 irq_domain_remove(irqsteer_data->domain);
246
247 clk_disable_unprepare(irqsteer_data->ipg_clk);
248
249 return 0;
250}
251
252#ifdef CONFIG_PM_SLEEP
253static void imx_irqsteer_save_regs(struct irqsteer_data *data)
254{
255 int i;
256
257 for (i = 0; i < data->reg_num; i++)
258 data->saved_reg[i] = readl_relaxed(data->regs +
259 CHANMASK(i, data->reg_num));
260}
261
262static void imx_irqsteer_restore_regs(struct irqsteer_data *data)
263{
264 int i;
265
266 writel_relaxed(BIT(data->channel), data->regs + CHANCTRL);
267 for (i = 0; i < data->reg_num; i++)
268 writel_relaxed(data->saved_reg[i],
269 data->regs + CHANMASK(i, data->reg_num));
270}
271
272static int imx_irqsteer_suspend(struct device *dev)
273{
274 struct irqsteer_data *irqsteer_data = dev_get_drvdata(dev);
275
276 imx_irqsteer_save_regs(irqsteer_data);
277 clk_disable_unprepare(irqsteer_data->ipg_clk);
278
279 return 0;
280}
281
282static int imx_irqsteer_resume(struct device *dev)
283{
284 struct irqsteer_data *irqsteer_data = dev_get_drvdata(dev);
285 int ret;
286
287 ret = clk_prepare_enable(irqsteer_data->ipg_clk);
288 if (ret) {
289 dev_err(dev, "failed to enable ipg clk: %d\n", ret);
290 return ret;
291 }
292 imx_irqsteer_restore_regs(irqsteer_data);
293
294 return 0;
295}
296#endif
297
298static const struct dev_pm_ops imx_irqsteer_pm_ops = {
299 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_irqsteer_suspend, imx_irqsteer_resume)
300};
301
302static const struct of_device_id imx_irqsteer_dt_ids[] = {
303 { .compatible = "fsl,imx-irqsteer", },
304 {},
305};
306
307static struct platform_driver imx_irqsteer_driver = {
308 .driver = {
309 .name = "imx-irqsteer",
310 .of_match_table = imx_irqsteer_dt_ids,
311 .pm = &imx_irqsteer_pm_ops,
312 },
313 .probe = imx_irqsteer_probe,
314 .remove = imx_irqsteer_remove,
315};
316builtin_platform_driver(imx_irqsteer_driver);
317