1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PRU-ICSS INTC IRQChip driver for various TI SoCs
4 *
5 * Copyright (C) 2016-2020 Texas Instruments Incorporated - http://www.ti.com/
6 *
7 * Author(s):
8 * Andrew F. Davis <afd@ti.com>
9 * Suman Anna <s-anna@ti.com>
10 * Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org> for Texas Instruments
11 *
12 * Copyright (C) 2019 David Lechner <david@lechnology.com>
13 */
14
15#include <linux/interrupt.h>
16#include <linux/irq.h>
17#include <linux/irqchip/chained_irq.h>
18#include <linux/irqdomain.h>
19#include <linux/module.h>
20#include <linux/of.h>
21#include <linux/platform_device.h>
22
23/*
24 * Number of host interrupts reaching the main MPU sub-system. Note that this
25 * is not the same as the total number of host interrupts supported by the PRUSS
26 * INTC instance
27 */
28#define MAX_NUM_HOST_IRQS 8
29
30/* minimum starting host interrupt number for MPU */
31#define FIRST_PRU_HOST_INT 2
32
33/* PRU_ICSS_INTC registers */
34#define PRU_INTC_REVID 0x0000
35#define PRU_INTC_CR 0x0004
36#define PRU_INTC_GER 0x0010
37#define PRU_INTC_GNLR 0x001c
38#define PRU_INTC_SISR 0x0020
39#define PRU_INTC_SICR 0x0024
40#define PRU_INTC_EISR 0x0028
41#define PRU_INTC_EICR 0x002c
42#define PRU_INTC_HIEISR 0x0034
43#define PRU_INTC_HIDISR 0x0038
44#define PRU_INTC_GPIR 0x0080
45#define PRU_INTC_SRSR(x) (0x0200 + (x) * 4)
46#define PRU_INTC_SECR(x) (0x0280 + (x) * 4)
47#define PRU_INTC_ESR(x) (0x0300 + (x) * 4)
48#define PRU_INTC_ECR(x) (0x0380 + (x) * 4)
49#define PRU_INTC_CMR(x) (0x0400 + (x) * 4)
50#define PRU_INTC_HMR(x) (0x0800 + (x) * 4)
51#define PRU_INTC_HIPIR(x) (0x0900 + (x) * 4)
52#define PRU_INTC_SIPR(x) (0x0d00 + (x) * 4)
53#define PRU_INTC_SITR(x) (0x0d80 + (x) * 4)
54#define PRU_INTC_HINLR(x) (0x1100 + (x) * 4)
55#define PRU_INTC_HIER 0x1500
56
57/* CMR register bit-field macros */
58#define CMR_EVT_MAP_MASK 0xf
59#define CMR_EVT_MAP_BITS 8
60#define CMR_EVT_PER_REG 4
61
62/* HMR register bit-field macros */
63#define HMR_CH_MAP_MASK 0xf
64#define HMR_CH_MAP_BITS 8
65#define HMR_CH_PER_REG 4
66
67/* HIPIR register bit-fields */
68#define INTC_HIPIR_NONE_HINT 0x80000000
69
70#define MAX_PRU_SYS_EVENTS 160
71#define MAX_PRU_CHANNELS 20
72
73/**
74 * struct pruss_intc_map_record - keeps track of actual mapping state
75 * @value: The currently mapped value (channel or host)
76 * @ref_count: Keeps track of number of current users of this resource
77 */
78struct pruss_intc_map_record {
79 u8 value;
80 u8 ref_count;
81};
82
83/**
84 * struct pruss_intc_match_data - match data to handle SoC variations
85 * @num_system_events: number of input system events handled by the PRUSS INTC
86 * @num_host_events: number of host events (which is equal to number of
87 * channels) supported by the PRUSS INTC
88 */
89struct pruss_intc_match_data {
90 u8 num_system_events;
91 u8 num_host_events;
92};
93
94/**
95 * struct pruss_intc - PRUSS interrupt controller structure
96 * @event_channel: current state of system event to channel mappings
97 * @channel_host: current state of channel to host mappings
98 * @irqs: kernel irq numbers corresponding to PRUSS host interrupts
99 * @base: base virtual address of INTC register space
100 * @domain: irq domain for this interrupt controller
101 * @soc_config: cached PRUSS INTC IP configuration data
102 * @dev: PRUSS INTC device pointer
103 * @lock: mutex to serialize interrupts mapping
104 */
105struct pruss_intc {
106 struct pruss_intc_map_record event_channel[MAX_PRU_SYS_EVENTS];
107 struct pruss_intc_map_record channel_host[MAX_PRU_CHANNELS];
108 unsigned int irqs[MAX_NUM_HOST_IRQS];
109 void __iomem *base;
110 struct irq_domain *domain;
111 const struct pruss_intc_match_data *soc_config;
112 struct device *dev;
113 struct mutex lock; /* PRUSS INTC lock */
114};
115
116/**
117 * struct pruss_host_irq_data - PRUSS host irq data structure
118 * @intc: PRUSS interrupt controller pointer
119 * @host_irq: host irq number
120 */
121struct pruss_host_irq_data {
122 struct pruss_intc *intc;
123 u8 host_irq;
124};
125
126static inline u32 pruss_intc_read_reg(struct pruss_intc *intc, unsigned int reg)
127{
128 return readl_relaxed(intc->base + reg);
129}
130
131static inline void pruss_intc_write_reg(struct pruss_intc *intc,
132 unsigned int reg, u32 val)
133{
134 writel_relaxed(val, intc->base + reg);
135}
136
137static void pruss_intc_update_cmr(struct pruss_intc *intc, unsigned int evt,
138 u8 ch)
139{
140 u32 idx, offset, val;
141
142 idx = evt / CMR_EVT_PER_REG;
143 offset = (evt % CMR_EVT_PER_REG) * CMR_EVT_MAP_BITS;
144
145 val = pruss_intc_read_reg(intc, PRU_INTC_CMR(idx));
146 val &= ~(CMR_EVT_MAP_MASK << offset);
147 val |= ch << offset;
148 pruss_intc_write_reg(intc, PRU_INTC_CMR(idx), val);
149
150 dev_dbg(intc->dev, "SYSEV%u -> CH%d (CMR%d 0x%08x)\n", evt, ch,
151 idx, pruss_intc_read_reg(intc, PRU_INTC_CMR(idx)));
152}
153
154static void pruss_intc_update_hmr(struct pruss_intc *intc, u8 ch, u8 host)
155{
156 u32 idx, offset, val;
157
158 idx = ch / HMR_CH_PER_REG;
159 offset = (ch % HMR_CH_PER_REG) * HMR_CH_MAP_BITS;
160
161 val = pruss_intc_read_reg(intc, PRU_INTC_HMR(idx));
162 val &= ~(HMR_CH_MAP_MASK << offset);
163 val |= host << offset;
164 pruss_intc_write_reg(intc, PRU_INTC_HMR(idx), val);
165
166 dev_dbg(intc->dev, "CH%d -> HOST%d (HMR%d 0x%08x)\n", ch, host, idx,
167 pruss_intc_read_reg(intc, PRU_INTC_HMR(idx)));
168}
169
170/**
171 * pruss_intc_map() - configure the PRUSS INTC
172 * @intc: PRUSS interrupt controller pointer
173 * @hwirq: the system event number
174 *
175 * Configures the PRUSS INTC with the provided configuration from the one parsed
176 * in the xlate function.
177 */
178static void pruss_intc_map(struct pruss_intc *intc, unsigned long hwirq)
179{
180 struct device *dev = intc->dev;
181 u8 ch, host, reg_idx;
182 u32 val;
183
184 mutex_lock(&intc->lock);
185
186 intc->event_channel[hwirq].ref_count++;
187
188 ch = intc->event_channel[hwirq].value;
189 host = intc->channel_host[ch].value;
190
191 pruss_intc_update_cmr(intc, evt: hwirq, ch);
192
193 reg_idx = hwirq / 32;
194 val = BIT(hwirq % 32);
195
196 /* clear and enable system event */
197 pruss_intc_write_reg(intc, PRU_INTC_ESR(reg_idx), val);
198 pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val);
199
200 if (++intc->channel_host[ch].ref_count == 1) {
201 pruss_intc_update_hmr(intc, ch, host);
202
203 /* enable host interrupts */
204 pruss_intc_write_reg(intc, PRU_INTC_HIEISR, val: host);
205 }
206
207 dev_dbg(dev, "mapped system_event = %lu channel = %d host = %d",
208 hwirq, ch, host);
209
210 mutex_unlock(lock: &intc->lock);
211}
212
213/**
214 * pruss_intc_unmap() - unconfigure the PRUSS INTC
215 * @intc: PRUSS interrupt controller pointer
216 * @hwirq: the system event number
217 *
218 * Undo whatever was done in pruss_intc_map() for a PRU core.
219 * Mappings are reference counted, so resources are only disabled when there
220 * are no longer any users.
221 */
222static void pruss_intc_unmap(struct pruss_intc *intc, unsigned long hwirq)
223{
224 u8 ch, host, reg_idx;
225 u32 val;
226
227 mutex_lock(&intc->lock);
228
229 ch = intc->event_channel[hwirq].value;
230 host = intc->channel_host[ch].value;
231
232 if (--intc->channel_host[ch].ref_count == 0) {
233 /* disable host interrupts */
234 pruss_intc_write_reg(intc, PRU_INTC_HIDISR, val: host);
235
236 /* clear the map using reset value 0 */
237 pruss_intc_update_hmr(intc, ch, host: 0);
238 }
239
240 intc->event_channel[hwirq].ref_count--;
241 reg_idx = hwirq / 32;
242 val = BIT(hwirq % 32);
243
244 /* disable system events */
245 pruss_intc_write_reg(intc, PRU_INTC_ECR(reg_idx), val);
246 /* clear any pending status */
247 pruss_intc_write_reg(intc, PRU_INTC_SECR(reg_idx), val);
248
249 /* clear the map using reset value 0 */
250 pruss_intc_update_cmr(intc, evt: hwirq, ch: 0);
251
252 dev_dbg(intc->dev, "unmapped system_event = %lu channel = %d host = %d\n",
253 hwirq, ch, host);
254
255 mutex_unlock(lock: &intc->lock);
256}
257
258static void pruss_intc_init(struct pruss_intc *intc)
259{
260 const struct pruss_intc_match_data *soc_config = intc->soc_config;
261 int num_chnl_map_regs, num_host_intr_regs, num_event_type_regs, i;
262
263 num_chnl_map_regs = DIV_ROUND_UP(soc_config->num_system_events,
264 CMR_EVT_PER_REG);
265 num_host_intr_regs = DIV_ROUND_UP(soc_config->num_host_events,
266 HMR_CH_PER_REG);
267 num_event_type_regs = DIV_ROUND_UP(soc_config->num_system_events, 32);
268
269 /*
270 * configure polarity (SIPR register) to active high and
271 * type (SITR register) to level interrupt for all system events
272 */
273 for (i = 0; i < num_event_type_regs; i++) {
274 pruss_intc_write_reg(intc, PRU_INTC_SIPR(i), val: 0xffffffff);
275 pruss_intc_write_reg(intc, PRU_INTC_SITR(i), val: 0);
276 }
277
278 /* clear all interrupt channel map registers, 4 events per register */
279 for (i = 0; i < num_chnl_map_regs; i++)
280 pruss_intc_write_reg(intc, PRU_INTC_CMR(i), val: 0);
281
282 /* clear all host interrupt map registers, 4 channels per register */
283 for (i = 0; i < num_host_intr_regs; i++)
284 pruss_intc_write_reg(intc, PRU_INTC_HMR(i), val: 0);
285
286 /* global interrupt enable */
287 pruss_intc_write_reg(intc, PRU_INTC_GER, val: 1);
288}
289
290static void pruss_intc_irq_ack(struct irq_data *data)
291{
292 struct pruss_intc *intc = irq_data_get_irq_chip_data(d: data);
293 unsigned int hwirq = data->hwirq;
294
295 pruss_intc_write_reg(intc, PRU_INTC_SICR, val: hwirq);
296}
297
298static void pruss_intc_irq_mask(struct irq_data *data)
299{
300 struct pruss_intc *intc = irq_data_get_irq_chip_data(d: data);
301 unsigned int hwirq = data->hwirq;
302
303 pruss_intc_write_reg(intc, PRU_INTC_EICR, val: hwirq);
304}
305
306static void pruss_intc_irq_unmask(struct irq_data *data)
307{
308 struct pruss_intc *intc = irq_data_get_irq_chip_data(d: data);
309 unsigned int hwirq = data->hwirq;
310
311 pruss_intc_write_reg(intc, PRU_INTC_EISR, val: hwirq);
312}
313
314static int pruss_intc_irq_reqres(struct irq_data *data)
315{
316 if (!try_module_get(THIS_MODULE))
317 return -ENODEV;
318
319 return 0;
320}
321
322static void pruss_intc_irq_relres(struct irq_data *data)
323{
324 module_put(THIS_MODULE);
325}
326
327static int pruss_intc_irq_get_irqchip_state(struct irq_data *data,
328 enum irqchip_irq_state which,
329 bool *state)
330{
331 struct pruss_intc *intc = irq_data_get_irq_chip_data(d: data);
332 u32 reg, mask, srsr;
333
334 if (which != IRQCHIP_STATE_PENDING)
335 return -EINVAL;
336
337 reg = PRU_INTC_SRSR(data->hwirq / 32);
338 mask = BIT(data->hwirq % 32);
339
340 srsr = pruss_intc_read_reg(intc, reg);
341
342 *state = !!(srsr & mask);
343
344 return 0;
345}
346
347static int pruss_intc_irq_set_irqchip_state(struct irq_data *data,
348 enum irqchip_irq_state which,
349 bool state)
350{
351 struct pruss_intc *intc = irq_data_get_irq_chip_data(d: data);
352
353 if (which != IRQCHIP_STATE_PENDING)
354 return -EINVAL;
355
356 if (state)
357 pruss_intc_write_reg(intc, PRU_INTC_SISR, val: data->hwirq);
358 else
359 pruss_intc_write_reg(intc, PRU_INTC_SICR, val: data->hwirq);
360
361 return 0;
362}
363
364static struct irq_chip pruss_irqchip = {
365 .name = "pruss-intc",
366 .irq_ack = pruss_intc_irq_ack,
367 .irq_mask = pruss_intc_irq_mask,
368 .irq_unmask = pruss_intc_irq_unmask,
369 .irq_request_resources = pruss_intc_irq_reqres,
370 .irq_release_resources = pruss_intc_irq_relres,
371 .irq_get_irqchip_state = pruss_intc_irq_get_irqchip_state,
372 .irq_set_irqchip_state = pruss_intc_irq_set_irqchip_state,
373};
374
375static int pruss_intc_validate_mapping(struct pruss_intc *intc, int event,
376 int channel, int host)
377{
378 struct device *dev = intc->dev;
379 int ret = 0;
380
381 mutex_lock(&intc->lock);
382
383 /* check if sysevent already assigned */
384 if (intc->event_channel[event].ref_count > 0 &&
385 intc->event_channel[event].value != channel) {
386 dev_err(dev, "event %d (req. ch %d) already assigned to channel %d\n",
387 event, channel, intc->event_channel[event].value);
388 ret = -EBUSY;
389 goto unlock;
390 }
391
392 /* check if channel already assigned */
393 if (intc->channel_host[channel].ref_count > 0 &&
394 intc->channel_host[channel].value != host) {
395 dev_err(dev, "channel %d (req. host %d) already assigned to host %d\n",
396 channel, host, intc->channel_host[channel].value);
397 ret = -EBUSY;
398 goto unlock;
399 }
400
401 intc->event_channel[event].value = channel;
402 intc->channel_host[channel].value = host;
403
404unlock:
405 mutex_unlock(lock: &intc->lock);
406 return ret;
407}
408
409static int
410pruss_intc_irq_domain_xlate(struct irq_domain *d, struct device_node *node,
411 const u32 *intspec, unsigned int intsize,
412 unsigned long *out_hwirq, unsigned int *out_type)
413{
414 struct pruss_intc *intc = d->host_data;
415 struct device *dev = intc->dev;
416 int ret, sys_event, channel, host;
417
418 if (intsize < 3)
419 return -EINVAL;
420
421 sys_event = intspec[0];
422 if (sys_event < 0 || sys_event >= intc->soc_config->num_system_events) {
423 dev_err(dev, "%d is not valid event number\n", sys_event);
424 return -EINVAL;
425 }
426
427 channel = intspec[1];
428 if (channel < 0 || channel >= intc->soc_config->num_host_events) {
429 dev_err(dev, "%d is not valid channel number", channel);
430 return -EINVAL;
431 }
432
433 host = intspec[2];
434 if (host < 0 || host >= intc->soc_config->num_host_events) {
435 dev_err(dev, "%d is not valid host irq number\n", host);
436 return -EINVAL;
437 }
438
439 /* check if requested sys_event was already mapped, if so validate it */
440 ret = pruss_intc_validate_mapping(intc, event: sys_event, channel, host);
441 if (ret)
442 return ret;
443
444 *out_hwirq = sys_event;
445 *out_type = IRQ_TYPE_LEVEL_HIGH;
446
447 return 0;
448}
449
450static int pruss_intc_irq_domain_map(struct irq_domain *d, unsigned int virq,
451 irq_hw_number_t hw)
452{
453 struct pruss_intc *intc = d->host_data;
454
455 pruss_intc_map(intc, hwirq: hw);
456
457 irq_set_chip_data(irq: virq, data: intc);
458 irq_set_chip_and_handler(irq: virq, chip: &pruss_irqchip, handle: handle_level_irq);
459
460 return 0;
461}
462
463static void pruss_intc_irq_domain_unmap(struct irq_domain *d, unsigned int virq)
464{
465 struct pruss_intc *intc = d->host_data;
466 unsigned long hwirq = irqd_to_hwirq(d: irq_get_irq_data(irq: virq));
467
468 irq_set_chip_and_handler(irq: virq, NULL, NULL);
469 irq_set_chip_data(irq: virq, NULL);
470 pruss_intc_unmap(intc, hwirq);
471}
472
473static const struct irq_domain_ops pruss_intc_irq_domain_ops = {
474 .xlate = pruss_intc_irq_domain_xlate,
475 .map = pruss_intc_irq_domain_map,
476 .unmap = pruss_intc_irq_domain_unmap,
477};
478
479static void pruss_intc_irq_handler(struct irq_desc *desc)
480{
481 unsigned int irq = irq_desc_get_irq(desc);
482 struct irq_chip *chip = irq_desc_get_chip(desc);
483 struct pruss_host_irq_data *host_irq_data = irq_get_handler_data(irq);
484 struct pruss_intc *intc = host_irq_data->intc;
485 u8 host_irq = host_irq_data->host_irq + FIRST_PRU_HOST_INT;
486
487 chained_irq_enter(chip, desc);
488
489 while (true) {
490 u32 hipir;
491 int hwirq, err;
492
493 /* get highest priority pending PRUSS system event */
494 hipir = pruss_intc_read_reg(intc, PRU_INTC_HIPIR(host_irq));
495 if (hipir & INTC_HIPIR_NONE_HINT)
496 break;
497
498 hwirq = hipir & GENMASK(9, 0);
499 err = generic_handle_domain_irq(domain: intc->domain, hwirq);
500
501 /*
502 * NOTE: manually ACK any system events that do not have a
503 * handler mapped yet
504 */
505 if (WARN_ON_ONCE(err))
506 pruss_intc_write_reg(intc, PRU_INTC_SICR, val: hwirq);
507 }
508
509 chained_irq_exit(chip, desc);
510}
511
512static const char * const irq_names[MAX_NUM_HOST_IRQS] = {
513 "host_intr0", "host_intr1", "host_intr2", "host_intr3",
514 "host_intr4", "host_intr5", "host_intr6", "host_intr7",
515};
516
517static int pruss_intc_probe(struct platform_device *pdev)
518{
519 const struct pruss_intc_match_data *data;
520 struct device *dev = &pdev->dev;
521 struct pruss_intc *intc;
522 struct pruss_host_irq_data *host_data;
523 int i, irq, ret;
524 u8 max_system_events, irqs_reserved = 0;
525
526 data = of_device_get_match_data(dev);
527 if (!data)
528 return -ENODEV;
529
530 max_system_events = data->num_system_events;
531
532 intc = devm_kzalloc(dev, size: sizeof(*intc), GFP_KERNEL);
533 if (!intc)
534 return -ENOMEM;
535
536 intc->soc_config = data;
537 intc->dev = dev;
538 platform_set_drvdata(pdev, data: intc);
539
540 intc->base = devm_platform_ioremap_resource(pdev, index: 0);
541 if (IS_ERR(ptr: intc->base))
542 return PTR_ERR(ptr: intc->base);
543
544 ret = of_property_read_u8(np: dev->of_node, propname: "ti,irqs-reserved",
545 out_value: &irqs_reserved);
546
547 /*
548 * The irqs-reserved is used only for some SoC's therefore not having
549 * this property is still valid
550 */
551 if (ret < 0 && ret != -EINVAL)
552 return ret;
553
554 pruss_intc_init(intc);
555
556 mutex_init(&intc->lock);
557
558 intc->domain = irq_domain_add_linear(of_node: dev->of_node, size: max_system_events,
559 ops: &pruss_intc_irq_domain_ops, host_data: intc);
560 if (!intc->domain)
561 return -ENOMEM;
562
563 for (i = 0; i < MAX_NUM_HOST_IRQS; i++) {
564 if (irqs_reserved & BIT(i))
565 continue;
566
567 irq = platform_get_irq_byname(pdev, irq_names[i]);
568 if (irq < 0) {
569 ret = irq;
570 goto fail_irq;
571 }
572
573 intc->irqs[i] = irq;
574
575 host_data = devm_kzalloc(dev, size: sizeof(*host_data), GFP_KERNEL);
576 if (!host_data) {
577 ret = -ENOMEM;
578 goto fail_irq;
579 }
580
581 host_data->intc = intc;
582 host_data->host_irq = i;
583
584 irq_set_handler_data(irq, data: host_data);
585 irq_set_chained_handler(irq, handle: pruss_intc_irq_handler);
586 }
587
588 return 0;
589
590fail_irq:
591 while (--i >= 0) {
592 if (intc->irqs[i])
593 irq_set_chained_handler_and_data(irq: intc->irqs[i], NULL,
594 NULL);
595 }
596
597 irq_domain_remove(host: intc->domain);
598
599 return ret;
600}
601
602static void pruss_intc_remove(struct platform_device *pdev)
603{
604 struct pruss_intc *intc = platform_get_drvdata(pdev);
605 u8 max_system_events = intc->soc_config->num_system_events;
606 unsigned int hwirq;
607 int i;
608
609 for (i = 0; i < MAX_NUM_HOST_IRQS; i++) {
610 if (intc->irqs[i])
611 irq_set_chained_handler_and_data(irq: intc->irqs[i], NULL,
612 NULL);
613 }
614
615 for (hwirq = 0; hwirq < max_system_events; hwirq++)
616 irq_dispose_mapping(virq: irq_find_mapping(domain: intc->domain, hwirq));
617
618 irq_domain_remove(host: intc->domain);
619}
620
621static const struct pruss_intc_match_data pruss_intc_data = {
622 .num_system_events = 64,
623 .num_host_events = 10,
624};
625
626static const struct pruss_intc_match_data icssg_intc_data = {
627 .num_system_events = 160,
628 .num_host_events = 20,
629};
630
631static const struct of_device_id pruss_intc_of_match[] = {
632 {
633 .compatible = "ti,pruss-intc",
634 .data = &pruss_intc_data,
635 },
636 {
637 .compatible = "ti,icssg-intc",
638 .data = &icssg_intc_data,
639 },
640 { /* sentinel */ },
641};
642MODULE_DEVICE_TABLE(of, pruss_intc_of_match);
643
644static struct platform_driver pruss_intc_driver = {
645 .driver = {
646 .name = "pruss-intc",
647 .of_match_table = pruss_intc_of_match,
648 .suppress_bind_attrs = true,
649 },
650 .probe = pruss_intc_probe,
651 .remove_new = pruss_intc_remove,
652};
653module_platform_driver(pruss_intc_driver);
654
655MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
656MODULE_AUTHOR("Suman Anna <s-anna@ti.com>");
657MODULE_AUTHOR("Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>");
658MODULE_DESCRIPTION("TI PRU-ICSS INTC Driver");
659MODULE_LICENSE("GPL v2");
660

source code of linux/drivers/irqchip/irq-pruss-intc.c