1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) Maxime Coquelin 2015
4 * Copyright (C) STMicroelectronics 2017-2024
5 * Author: Maxime Coquelin <mcoquelin.stm32@gmail.com>
6 */
7
8 #include <linux/bitops.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/irq.h>
12 #include <linux/irqchip.h>
13 #include <linux/irqchip/chained_irq.h>
14 #include <linux/irqdomain.h>
15 #include <linux/of_address.h>
16 #include <linux/of_irq.h>
17
18 #define IRQS_PER_BANK 32
19
20 struct stm32_exti_bank {
21 u32 imr_ofst;
22 u32 emr_ofst;
23 u32 rtsr_ofst;
24 u32 ftsr_ofst;
25 u32 swier_ofst;
26 u32 rpr_ofst;
27 };
28
29 struct stm32_exti_drv_data {
30 const struct stm32_exti_bank **exti_banks;
31 const u8 *desc_irqs;
32 u32 bank_nr;
33 };
34
35 struct stm32_exti_chip_data {
36 struct stm32_exti_host_data *host_data;
37 const struct stm32_exti_bank *reg_bank;
38 u32 wake_active;
39 u32 mask_cache;
40 u32 rtsr_cache;
41 u32 ftsr_cache;
42 u32 event_reserved;
43 };
44
45 struct stm32_exti_host_data {
46 void __iomem *base;
47 struct device *dev;
48 struct stm32_exti_chip_data *chips_data;
49 const struct stm32_exti_drv_data *drv_data;
50 };
51
52 static const struct stm32_exti_bank stm32f4xx_exti_b1 = {
53 .imr_ofst = 0x00,
54 .emr_ofst = 0x04,
55 .rtsr_ofst = 0x08,
56 .ftsr_ofst = 0x0C,
57 .swier_ofst = 0x10,
58 .rpr_ofst = 0x14,
59 };
60
61 static const struct stm32_exti_bank *stm32f4xx_exti_banks[] = {
62 &stm32f4xx_exti_b1,
63 };
64
65 static const struct stm32_exti_drv_data stm32f4xx_drv_data = {
66 .exti_banks = stm32f4xx_exti_banks,
67 .bank_nr = ARRAY_SIZE(stm32f4xx_exti_banks),
68 };
69
70 static const struct stm32_exti_bank stm32h7xx_exti_b1 = {
71 .imr_ofst = 0x80,
72 .emr_ofst = 0x84,
73 .rtsr_ofst = 0x00,
74 .ftsr_ofst = 0x04,
75 .swier_ofst = 0x08,
76 .rpr_ofst = 0x88,
77 };
78
79 static const struct stm32_exti_bank stm32h7xx_exti_b2 = {
80 .imr_ofst = 0x90,
81 .emr_ofst = 0x94,
82 .rtsr_ofst = 0x20,
83 .ftsr_ofst = 0x24,
84 .swier_ofst = 0x28,
85 .rpr_ofst = 0x98,
86 };
87
88 static const struct stm32_exti_bank stm32h7xx_exti_b3 = {
89 .imr_ofst = 0xA0,
90 .emr_ofst = 0xA4,
91 .rtsr_ofst = 0x40,
92 .ftsr_ofst = 0x44,
93 .swier_ofst = 0x48,
94 .rpr_ofst = 0xA8,
95 };
96
97 static const struct stm32_exti_bank *stm32h7xx_exti_banks[] = {
98 &stm32h7xx_exti_b1,
99 &stm32h7xx_exti_b2,
100 &stm32h7xx_exti_b3,
101 };
102
103 static const struct stm32_exti_drv_data stm32h7xx_drv_data = {
104 .exti_banks = stm32h7xx_exti_banks,
105 .bank_nr = ARRAY_SIZE(stm32h7xx_exti_banks),
106 };
107
stm32_exti_pending(struct irq_chip_generic * gc)108 static unsigned long stm32_exti_pending(struct irq_chip_generic *gc)
109 {
110 struct stm32_exti_chip_data *chip_data = gc->private;
111 const struct stm32_exti_bank *stm32_bank = chip_data->reg_bank;
112
113 return irq_reg_readl(gc, stm32_bank->rpr_ofst);
114 }
115
stm32_irq_handler(struct irq_desc * desc)116 static void stm32_irq_handler(struct irq_desc *desc)
117 {
118 struct irq_domain *domain = irq_desc_get_handler_data(desc);
119 struct irq_chip *chip = irq_desc_get_chip(desc);
120 unsigned int nbanks = domain->gc->num_chips;
121 struct irq_chip_generic *gc;
122 unsigned long pending;
123 int n, i, irq_base = 0;
124
125 chained_irq_enter(chip, desc);
126
127 for (i = 0; i < nbanks; i++, irq_base += IRQS_PER_BANK) {
128 gc = irq_get_domain_generic_chip(domain, irq_base);
129
130 while ((pending = stm32_exti_pending(gc))) {
131 for_each_set_bit(n, &pending, IRQS_PER_BANK)
132 generic_handle_domain_irq(domain, irq_base + n);
133 }
134 }
135
136 chained_irq_exit(chip, desc);
137 }
138
stm32_exti_set_type(struct irq_data * d,unsigned int type,u32 * rtsr,u32 * ftsr)139 static int stm32_exti_set_type(struct irq_data *d,
140 unsigned int type, u32 *rtsr, u32 *ftsr)
141 {
142 u32 mask = BIT(d->hwirq % IRQS_PER_BANK);
143
144 switch (type) {
145 case IRQ_TYPE_EDGE_RISING:
146 *rtsr |= mask;
147 *ftsr &= ~mask;
148 break;
149 case IRQ_TYPE_EDGE_FALLING:
150 *rtsr &= ~mask;
151 *ftsr |= mask;
152 break;
153 case IRQ_TYPE_EDGE_BOTH:
154 *rtsr |= mask;
155 *ftsr |= mask;
156 break;
157 default:
158 return -EINVAL;
159 }
160
161 return 0;
162 }
163
stm32_irq_set_type(struct irq_data * d,unsigned int type)164 static int stm32_irq_set_type(struct irq_data *d, unsigned int type)
165 {
166 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
167 struct stm32_exti_chip_data *chip_data = gc->private;
168 const struct stm32_exti_bank *stm32_bank = chip_data->reg_bank;
169 u32 rtsr, ftsr;
170 int err;
171
172 irq_gc_lock(gc);
173
174 rtsr = irq_reg_readl(gc, stm32_bank->rtsr_ofst);
175 ftsr = irq_reg_readl(gc, stm32_bank->ftsr_ofst);
176
177 err = stm32_exti_set_type(d, type, &rtsr, &ftsr);
178 if (err)
179 goto unlock;
180
181 irq_reg_writel(gc, rtsr, stm32_bank->rtsr_ofst);
182 irq_reg_writel(gc, ftsr, stm32_bank->ftsr_ofst);
183
184 unlock:
185 irq_gc_unlock(gc);
186
187 return err;
188 }
189
stm32_chip_suspend(struct stm32_exti_chip_data * chip_data,u32 wake_active)190 static void stm32_chip_suspend(struct stm32_exti_chip_data *chip_data,
191 u32 wake_active)
192 {
193 const struct stm32_exti_bank *stm32_bank = chip_data->reg_bank;
194 void __iomem *base = chip_data->host_data->base;
195
196 /* save rtsr, ftsr registers */
197 chip_data->rtsr_cache = readl_relaxed(base + stm32_bank->rtsr_ofst);
198 chip_data->ftsr_cache = readl_relaxed(base + stm32_bank->ftsr_ofst);
199
200 writel_relaxed(wake_active, base + stm32_bank->imr_ofst);
201 }
202
stm32_chip_resume(struct stm32_exti_chip_data * chip_data,u32 mask_cache)203 static void stm32_chip_resume(struct stm32_exti_chip_data *chip_data,
204 u32 mask_cache)
205 {
206 const struct stm32_exti_bank *stm32_bank = chip_data->reg_bank;
207 void __iomem *base = chip_data->host_data->base;
208
209 /* restore rtsr, ftsr, registers */
210 writel_relaxed(chip_data->rtsr_cache, base + stm32_bank->rtsr_ofst);
211 writel_relaxed(chip_data->ftsr_cache, base + stm32_bank->ftsr_ofst);
212
213 writel_relaxed(mask_cache, base + stm32_bank->imr_ofst);
214 }
215
stm32_irq_suspend(struct irq_chip_generic * gc)216 static void stm32_irq_suspend(struct irq_chip_generic *gc)
217 {
218 struct stm32_exti_chip_data *chip_data = gc->private;
219
220 irq_gc_lock(gc);
221 stm32_chip_suspend(chip_data, gc->wake_active);
222 irq_gc_unlock(gc);
223 }
224
stm32_irq_resume(struct irq_chip_generic * gc)225 static void stm32_irq_resume(struct irq_chip_generic *gc)
226 {
227 struct stm32_exti_chip_data *chip_data = gc->private;
228
229 irq_gc_lock(gc);
230 stm32_chip_resume(chip_data, gc->mask_cache);
231 irq_gc_unlock(gc);
232 }
233
stm32_exti_alloc(struct irq_domain * d,unsigned int virq,unsigned int nr_irqs,void * data)234 static int stm32_exti_alloc(struct irq_domain *d, unsigned int virq,
235 unsigned int nr_irqs, void *data)
236 {
237 struct irq_fwspec *fwspec = data;
238 irq_hw_number_t hwirq;
239
240 hwirq = fwspec->param[0];
241
242 irq_map_generic_chip(d, virq, hwirq);
243
244 return 0;
245 }
246
stm32_exti_free(struct irq_domain * d,unsigned int virq,unsigned int nr_irqs)247 static void stm32_exti_free(struct irq_domain *d, unsigned int virq,
248 unsigned int nr_irqs)
249 {
250 struct irq_data *data = irq_domain_get_irq_data(d, virq);
251
252 irq_domain_reset_irq_data(data);
253 }
254
255 static const struct irq_domain_ops irq_exti_domain_ops = {
256 .map = irq_map_generic_chip,
257 .alloc = stm32_exti_alloc,
258 .free = stm32_exti_free,
259 .xlate = irq_domain_xlate_twocell,
260 };
261
stm32_irq_ack(struct irq_data * d)262 static void stm32_irq_ack(struct irq_data *d)
263 {
264 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
265 struct stm32_exti_chip_data *chip_data = gc->private;
266 const struct stm32_exti_bank *stm32_bank = chip_data->reg_bank;
267
268 irq_gc_lock(gc);
269
270 irq_reg_writel(gc, d->mask, stm32_bank->rpr_ofst);
271
272 irq_gc_unlock(gc);
273 }
274
275 static struct
stm32_exti_host_init(const struct stm32_exti_drv_data * dd,struct device_node * node)276 stm32_exti_host_data *stm32_exti_host_init(const struct stm32_exti_drv_data *dd,
277 struct device_node *node)
278 {
279 struct stm32_exti_host_data *host_data;
280
281 host_data = kzalloc(sizeof(*host_data), GFP_KERNEL);
282 if (!host_data)
283 return NULL;
284
285 host_data->drv_data = dd;
286 host_data->chips_data = kcalloc(dd->bank_nr,
287 sizeof(struct stm32_exti_chip_data),
288 GFP_KERNEL);
289 if (!host_data->chips_data)
290 goto free_host_data;
291
292 host_data->base = of_iomap(node, 0);
293 if (!host_data->base) {
294 pr_err("%pOF: Unable to map registers\n", node);
295 goto free_chips_data;
296 }
297
298 return host_data;
299
300 free_chips_data:
301 kfree(host_data->chips_data);
302 free_host_data:
303 kfree(host_data);
304
305 return NULL;
306 }
307
308 static struct
stm32_exti_chip_init(struct stm32_exti_host_data * h_data,u32 bank_idx,struct device_node * node)309 stm32_exti_chip_data *stm32_exti_chip_init(struct stm32_exti_host_data *h_data,
310 u32 bank_idx,
311 struct device_node *node)
312 {
313 const struct stm32_exti_bank *stm32_bank;
314 struct stm32_exti_chip_data *chip_data;
315 void __iomem *base = h_data->base;
316
317 stm32_bank = h_data->drv_data->exti_banks[bank_idx];
318 chip_data = &h_data->chips_data[bank_idx];
319 chip_data->host_data = h_data;
320 chip_data->reg_bank = stm32_bank;
321
322 /*
323 * This IP has no reset, so after hot reboot we should
324 * clear registers to avoid residue
325 */
326 writel_relaxed(0, base + stm32_bank->imr_ofst);
327 writel_relaxed(0, base + stm32_bank->emr_ofst);
328
329 pr_info("%pOF: bank%d\n", node, bank_idx);
330
331 return chip_data;
332 }
333
stm32_exti_init(const struct stm32_exti_drv_data * drv_data,struct device_node * node)334 static int __init stm32_exti_init(const struct stm32_exti_drv_data *drv_data,
335 struct device_node *node)
336 {
337 struct stm32_exti_host_data *host_data;
338 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
339 int nr_irqs, ret, i;
340 struct irq_chip_generic *gc;
341 struct irq_domain *domain;
342
343 host_data = stm32_exti_host_init(drv_data, node);
344 if (!host_data)
345 return -ENOMEM;
346
347 domain = irq_domain_add_linear(node, drv_data->bank_nr * IRQS_PER_BANK,
348 &irq_exti_domain_ops, NULL);
349 if (!domain) {
350 pr_err("%pOFn: Could not register interrupt domain.\n",
351 node);
352 ret = -ENOMEM;
353 goto out_unmap;
354 }
355
356 ret = irq_alloc_domain_generic_chips(domain, IRQS_PER_BANK, 1, "exti",
357 handle_edge_irq, clr, 0, 0);
358 if (ret) {
359 pr_err("%pOF: Could not allocate generic interrupt chip.\n",
360 node);
361 goto out_free_domain;
362 }
363
364 for (i = 0; i < drv_data->bank_nr; i++) {
365 const struct stm32_exti_bank *stm32_bank;
366 struct stm32_exti_chip_data *chip_data;
367
368 stm32_bank = drv_data->exti_banks[i];
369 chip_data = stm32_exti_chip_init(host_data, i, node);
370
371 gc = irq_get_domain_generic_chip(domain, i * IRQS_PER_BANK);
372
373 gc->reg_base = host_data->base;
374 gc->chip_types->type = IRQ_TYPE_EDGE_BOTH;
375 gc->chip_types->chip.irq_ack = stm32_irq_ack;
376 gc->chip_types->chip.irq_mask = irq_gc_mask_clr_bit;
377 gc->chip_types->chip.irq_unmask = irq_gc_mask_set_bit;
378 gc->chip_types->chip.irq_set_type = stm32_irq_set_type;
379 gc->chip_types->chip.irq_set_wake = irq_gc_set_wake;
380 gc->suspend = stm32_irq_suspend;
381 gc->resume = stm32_irq_resume;
382 gc->wake_enabled = IRQ_MSK(IRQS_PER_BANK);
383
384 gc->chip_types->regs.mask = stm32_bank->imr_ofst;
385 gc->private = (void *)chip_data;
386 }
387
388 nr_irqs = of_irq_count(node);
389 for (i = 0; i < nr_irqs; i++) {
390 unsigned int irq = irq_of_parse_and_map(node, i);
391
392 irq_set_handler_data(irq, domain);
393 irq_set_chained_handler(irq, stm32_irq_handler);
394 }
395
396 return 0;
397
398 out_free_domain:
399 irq_domain_remove(domain);
400 out_unmap:
401 iounmap(host_data->base);
402 kfree(host_data->chips_data);
403 kfree(host_data);
404 return ret;
405 }
406
stm32f4_exti_of_init(struct device_node * np,struct device_node * parent)407 static int __init stm32f4_exti_of_init(struct device_node *np,
408 struct device_node *parent)
409 {
410 return stm32_exti_init(&stm32f4xx_drv_data, np);
411 }
412
413 IRQCHIP_DECLARE(stm32f4_exti, "st,stm32-exti", stm32f4_exti_of_init);
414
stm32h7_exti_of_init(struct device_node * np,struct device_node * parent)415 static int __init stm32h7_exti_of_init(struct device_node *np,
416 struct device_node *parent)
417 {
418 return stm32_exti_init(&stm32h7xx_drv_data, np);
419 }
420
421 IRQCHIP_DECLARE(stm32h7_exti, "st,stm32h7-exti", stm32h7_exti_of_init);
422