1// SPDX-License-Identifier: GPL-2.0
2// Copyright 2017 NXP
3
4/* INTMUX Block Diagram
5 *
6 * ________________
7 * interrupt source # 0 +---->| |
8 * | | |
9 * interrupt source # 1 +++-->| |
10 * ... | | | channel # 0 |--------->interrupt out # 0
11 * ... | | | |
12 * ... | | | |
13 * interrupt source # X-1 +++-->|________________|
14 * | | |
15 * | | |
16 * | | | ________________
17 * +---->| |
18 * | | | | |
19 * | +-->| |
20 * | | | | channel # 1 |--------->interrupt out # 1
21 * | | +>| |
22 * | | | | |
23 * | | | |________________|
24 * | | |
25 * | | |
26 * | | | ...
27 * | | | ...
28 * | | |
29 * | | | ________________
30 * +---->| |
31 * | | | |
32 * +-->| |
33 * | | channel # N |--------->interrupt out # N
34 * +>| |
35 * | |
36 * |________________|
37 *
38 *
39 * N: Interrupt Channel Instance Number (N=7)
40 * X: Interrupt Source Number for each channel (X=32)
41 *
42 * The INTMUX interrupt multiplexer has 8 channels, each channel receives 32
43 * interrupt sources and generates 1 interrupt output.
44 *
45 */
46
47#include <linux/clk.h>
48#include <linux/interrupt.h>
49#include <linux/irq.h>
50#include <linux/irqchip/chained_irq.h>
51#include <linux/irqdomain.h>
52#include <linux/kernel.h>
53#include <linux/mod_devicetable.h>
54#include <linux/of_irq.h>
55#include <linux/platform_device.h>
56#include <linux/spinlock.h>
57#include <linux/pm_runtime.h>
58
59#define CHANIER(n) (0x10 + (0x40 * n))
60#define CHANIPR(n) (0x20 + (0x40 * n))
61
62#define CHAN_MAX_NUM 0x8
63
64struct intmux_irqchip_data {
65 u32 saved_reg;
66 int chanidx;
67 int irq;
68 struct irq_domain *domain;
69};
70
71struct intmux_data {
72 raw_spinlock_t lock;
73 void __iomem *regs;
74 struct clk *ipg_clk;
75 int channum;
76 struct intmux_irqchip_data irqchip_data[] __counted_by(channum);
77};
78
79static void imx_intmux_irq_mask(struct irq_data *d)
80{
81 struct intmux_irqchip_data *irqchip_data = d->chip_data;
82 int idx = irqchip_data->chanidx;
83 struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
84 irqchip_data[idx]);
85 unsigned long flags;
86 void __iomem *reg;
87 u32 val;
88
89 raw_spin_lock_irqsave(&data->lock, flags);
90 reg = data->regs + CHANIER(idx);
91 val = readl_relaxed(reg);
92 /* disable the interrupt source of this channel */
93 val &= ~BIT(d->hwirq);
94 writel_relaxed(val, reg);
95 raw_spin_unlock_irqrestore(&data->lock, flags);
96}
97
98static void imx_intmux_irq_unmask(struct irq_data *d)
99{
100 struct intmux_irqchip_data *irqchip_data = d->chip_data;
101 int idx = irqchip_data->chanidx;
102 struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
103 irqchip_data[idx]);
104 unsigned long flags;
105 void __iomem *reg;
106 u32 val;
107
108 raw_spin_lock_irqsave(&data->lock, flags);
109 reg = data->regs + CHANIER(idx);
110 val = readl_relaxed(reg);
111 /* enable the interrupt source of this channel */
112 val |= BIT(d->hwirq);
113 writel_relaxed(val, reg);
114 raw_spin_unlock_irqrestore(&data->lock, flags);
115}
116
117static struct irq_chip imx_intmux_irq_chip __ro_after_init = {
118 .name = "intmux",
119 .irq_mask = imx_intmux_irq_mask,
120 .irq_unmask = imx_intmux_irq_unmask,
121};
122
123static int imx_intmux_irq_map(struct irq_domain *h, unsigned int irq,
124 irq_hw_number_t hwirq)
125{
126 struct intmux_irqchip_data *data = h->host_data;
127
128 irq_set_chip_data(irq, data);
129 irq_set_chip_and_handler(irq, chip: &imx_intmux_irq_chip, handle: handle_level_irq);
130
131 return 0;
132}
133
134static int imx_intmux_irq_xlate(struct irq_domain *d, struct device_node *node,
135 const u32 *intspec, unsigned int intsize,
136 unsigned long *out_hwirq, unsigned int *out_type)
137{
138 struct intmux_irqchip_data *irqchip_data = d->host_data;
139 int idx = irqchip_data->chanidx;
140 struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
141 irqchip_data[idx]);
142
143 /*
144 * two cells needed in interrupt specifier:
145 * the 1st cell: hw interrupt number
146 * the 2nd cell: channel index
147 */
148 if (WARN_ON(intsize != 2))
149 return -EINVAL;
150
151 if (WARN_ON(intspec[1] >= data->channum))
152 return -EINVAL;
153
154 *out_hwirq = intspec[0];
155 *out_type = IRQ_TYPE_LEVEL_HIGH;
156
157 return 0;
158}
159
160static int imx_intmux_irq_select(struct irq_domain *d, struct irq_fwspec *fwspec,
161 enum irq_domain_bus_token bus_token)
162{
163 struct intmux_irqchip_data *irqchip_data = d->host_data;
164
165 /* Not for us */
166 if (fwspec->fwnode != d->fwnode)
167 return false;
168
169 /* Handle pure domain searches */
170 if (!fwspec->param_count)
171 return d->bus_token == bus_token;
172
173 return irqchip_data->chanidx == fwspec->param[1];
174}
175
176static const struct irq_domain_ops imx_intmux_domain_ops = {
177 .map = imx_intmux_irq_map,
178 .xlate = imx_intmux_irq_xlate,
179 .select = imx_intmux_irq_select,
180};
181
182static void imx_intmux_irq_handler(struct irq_desc *desc)
183{
184 struct intmux_irqchip_data *irqchip_data = irq_desc_get_handler_data(desc);
185 int idx = irqchip_data->chanidx;
186 struct intmux_data *data = container_of(irqchip_data, struct intmux_data,
187 irqchip_data[idx]);
188 unsigned long irqstat;
189 int pos;
190
191 chained_irq_enter(chip: irq_desc_get_chip(desc), desc);
192
193 /* read the interrupt source pending status of this channel */
194 irqstat = readl_relaxed(data->regs + CHANIPR(idx));
195
196 for_each_set_bit(pos, &irqstat, 32)
197 generic_handle_domain_irq(domain: irqchip_data->domain, hwirq: pos);
198
199 chained_irq_exit(chip: irq_desc_get_chip(desc), desc);
200}
201
202static int imx_intmux_probe(struct platform_device *pdev)
203{
204 struct device_node *np = pdev->dev.of_node;
205 struct irq_domain *domain;
206 struct intmux_data *data;
207 int channum;
208 int i, ret;
209
210 channum = platform_irq_count(pdev);
211 if (channum == -EPROBE_DEFER) {
212 return -EPROBE_DEFER;
213 } else if (channum > CHAN_MAX_NUM) {
214 dev_err(&pdev->dev, "supports up to %d multiplex channels\n",
215 CHAN_MAX_NUM);
216 return -EINVAL;
217 }
218
219 data = devm_kzalloc(dev: &pdev->dev, struct_size(data, irqchip_data, channum), GFP_KERNEL);
220 if (!data)
221 return -ENOMEM;
222
223 data->regs = devm_platform_ioremap_resource(pdev, index: 0);
224 if (IS_ERR(ptr: data->regs)) {
225 dev_err(&pdev->dev, "failed to initialize reg\n");
226 return PTR_ERR(ptr: data->regs);
227 }
228
229 data->ipg_clk = devm_clk_get(dev: &pdev->dev, id: "ipg");
230 if (IS_ERR(ptr: data->ipg_clk))
231 return dev_err_probe(dev: &pdev->dev, err: PTR_ERR(ptr: data->ipg_clk),
232 fmt: "failed to get ipg clk\n");
233
234 data->channum = channum;
235 raw_spin_lock_init(&data->lock);
236
237 pm_runtime_get_noresume(dev: &pdev->dev);
238 pm_runtime_set_active(dev: &pdev->dev);
239 pm_runtime_enable(dev: &pdev->dev);
240
241 ret = clk_prepare_enable(clk: data->ipg_clk);
242 if (ret) {
243 dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret);
244 return ret;
245 }
246
247 for (i = 0; i < channum; i++) {
248 data->irqchip_data[i].chanidx = i;
249
250 data->irqchip_data[i].irq = irq_of_parse_and_map(node: np, index: i);
251 if (data->irqchip_data[i].irq <= 0) {
252 ret = -EINVAL;
253 dev_err(&pdev->dev, "failed to get irq\n");
254 goto out;
255 }
256
257 domain = irq_domain_add_linear(of_node: np, size: 32, ops: &imx_intmux_domain_ops,
258 host_data: &data->irqchip_data[i]);
259 if (!domain) {
260 ret = -ENOMEM;
261 dev_err(&pdev->dev, "failed to create IRQ domain\n");
262 goto out;
263 }
264 data->irqchip_data[i].domain = domain;
265 irq_domain_set_pm_device(d: domain, dev: &pdev->dev);
266
267 /* disable all interrupt sources of this channel firstly */
268 writel_relaxed(0, data->regs + CHANIER(i));
269
270 irq_set_chained_handler_and_data(irq: data->irqchip_data[i].irq,
271 handle: imx_intmux_irq_handler,
272 data: &data->irqchip_data[i]);
273 }
274
275 platform_set_drvdata(pdev, data);
276
277 /*
278 * Let pm_runtime_put() disable clock.
279 * If CONFIG_PM is not enabled, the clock will stay powered.
280 */
281 pm_runtime_put(dev: &pdev->dev);
282
283 return 0;
284out:
285 clk_disable_unprepare(clk: data->ipg_clk);
286 return ret;
287}
288
289static void imx_intmux_remove(struct platform_device *pdev)
290{
291 struct intmux_data *data = platform_get_drvdata(pdev);
292 int i;
293
294 for (i = 0; i < data->channum; i++) {
295 /* disable all interrupt sources of this channel */
296 writel_relaxed(0, data->regs + CHANIER(i));
297
298 irq_set_chained_handler_and_data(irq: data->irqchip_data[i].irq,
299 NULL, NULL);
300
301 irq_domain_remove(host: data->irqchip_data[i].domain);
302 }
303
304 pm_runtime_disable(dev: &pdev->dev);
305}
306
307#ifdef CONFIG_PM
308static int imx_intmux_runtime_suspend(struct device *dev)
309{
310 struct intmux_data *data = dev_get_drvdata(dev);
311 struct intmux_irqchip_data *irqchip_data;
312 int i;
313
314 for (i = 0; i < data->channum; i++) {
315 irqchip_data = &data->irqchip_data[i];
316 irqchip_data->saved_reg = readl_relaxed(data->regs + CHANIER(i));
317 }
318
319 clk_disable_unprepare(clk: data->ipg_clk);
320
321 return 0;
322}
323
324static int imx_intmux_runtime_resume(struct device *dev)
325{
326 struct intmux_data *data = dev_get_drvdata(dev);
327 struct intmux_irqchip_data *irqchip_data;
328 int ret, i;
329
330 ret = clk_prepare_enable(clk: data->ipg_clk);
331 if (ret) {
332 dev_err(dev, "failed to enable ipg clk: %d\n", ret);
333 return ret;
334 }
335
336 for (i = 0; i < data->channum; i++) {
337 irqchip_data = &data->irqchip_data[i];
338 writel_relaxed(irqchip_data->saved_reg, data->regs + CHANIER(i));
339 }
340
341 return 0;
342}
343#endif
344
345static const struct dev_pm_ops imx_intmux_pm_ops = {
346 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
347 pm_runtime_force_resume)
348 SET_RUNTIME_PM_OPS(imx_intmux_runtime_suspend,
349 imx_intmux_runtime_resume, NULL)
350};
351
352static const struct of_device_id imx_intmux_id[] = {
353 { .compatible = "fsl,imx-intmux", },
354 { /* sentinel */ },
355};
356
357static struct platform_driver imx_intmux_driver = {
358 .driver = {
359 .name = "imx-intmux",
360 .of_match_table = imx_intmux_id,
361 .pm = &imx_intmux_pm_ops,
362 },
363 .probe = imx_intmux_probe,
364 .remove_new = imx_intmux_remove,
365};
366builtin_platform_driver(imx_intmux_driver);
367

source code of linux/drivers/irqchip/irq-imx-intmux.c