1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Ingenic SoCs TCU IRQ driver
4 * Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net>
5 * Copyright (C) 2020 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
6 */
7
8 #include <linux/bitops.h>
9 #include <linux/clk.h>
10 #include <linux/clockchips.h>
11 #include <linux/clocksource.h>
12 #include <linux/cpuhotplug.h>
13 #include <linux/interrupt.h>
14 #include <linux/mfd/ingenic-tcu.h>
15 #include <linux/mfd/syscon.h>
16 #include <linux/of.h>
17 #include <linux/of_irq.h>
18 #include <linux/overflow.h>
19 #include <linux/platform_device.h>
20 #include <linux/regmap.h>
21 #include <linux/sched_clock.h>
22
23 #include <dt-bindings/clock/ingenic,tcu.h>
24
25 static DEFINE_PER_CPU(call_single_data_t, ingenic_cevt_csd);
26
27 struct ingenic_soc_info {
28 unsigned int num_channels;
29 };
30
31 struct ingenic_tcu_timer {
32 unsigned int cpu;
33 unsigned int channel;
34 struct clock_event_device cevt;
35 struct clk *clk;
36 char name[8];
37 };
38
39 struct ingenic_tcu {
40 struct regmap *map;
41 struct device_node *np;
42 struct clk *cs_clk;
43 unsigned int cs_channel;
44 struct clocksource cs;
45 unsigned long pwm_channels_mask;
46 struct ingenic_tcu_timer timers[];
47 };
48
49 static struct ingenic_tcu *ingenic_tcu;
50
ingenic_tcu_timer_read(void)51 static u64 notrace ingenic_tcu_timer_read(void)
52 {
53 struct ingenic_tcu *tcu = ingenic_tcu;
54 unsigned int count;
55
56 regmap_read(tcu->map, TCU_REG_TCNTc(tcu->cs_channel), &count);
57
58 return count;
59 }
60
ingenic_tcu_timer_cs_read(struct clocksource * cs)61 static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource *cs)
62 {
63 return ingenic_tcu_timer_read();
64 }
65
66 static inline struct ingenic_tcu *
to_ingenic_tcu(struct ingenic_tcu_timer * timer)67 to_ingenic_tcu(struct ingenic_tcu_timer *timer)
68 {
69 return container_of(timer, struct ingenic_tcu, timers[timer->cpu]);
70 }
71
72 static inline struct ingenic_tcu_timer *
to_ingenic_tcu_timer(struct clock_event_device * evt)73 to_ingenic_tcu_timer(struct clock_event_device *evt)
74 {
75 return container_of(evt, struct ingenic_tcu_timer, cevt);
76 }
77
ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device * evt)78 static int ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device *evt)
79 {
80 struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt);
81 struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
82
83 regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel));
84
85 return 0;
86 }
87
ingenic_tcu_cevt_set_next(unsigned long next,struct clock_event_device * evt)88 static int ingenic_tcu_cevt_set_next(unsigned long next,
89 struct clock_event_device *evt)
90 {
91 struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt);
92 struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
93
94 if (next > 0xffff)
95 return -EINVAL;
96
97 regmap_write(tcu->map, TCU_REG_TDFRc(timer->channel), next);
98 regmap_write(tcu->map, TCU_REG_TCNTc(timer->channel), 0);
99 regmap_write(tcu->map, TCU_REG_TESR, BIT(timer->channel));
100
101 return 0;
102 }
103
ingenic_per_cpu_event_handler(void * info)104 static void ingenic_per_cpu_event_handler(void *info)
105 {
106 struct clock_event_device *cevt = (struct clock_event_device *) info;
107
108 cevt->event_handler(cevt);
109 }
110
ingenic_tcu_cevt_cb(int irq,void * dev_id)111 static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id)
112 {
113 struct ingenic_tcu_timer *timer = dev_id;
114 struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
115 call_single_data_t *csd;
116
117 regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel));
118
119 if (timer->cevt.event_handler) {
120 csd = &per_cpu(ingenic_cevt_csd, timer->cpu);
121 csd->info = (void *) &timer->cevt;
122 csd->func = ingenic_per_cpu_event_handler;
123 smp_call_function_single_async(timer->cpu, csd);
124 }
125
126 return IRQ_HANDLED;
127 }
128
ingenic_tcu_get_clock(struct device_node * np,int id)129 static struct clk *ingenic_tcu_get_clock(struct device_node *np, int id)
130 {
131 struct of_phandle_args args;
132
133 args.np = np;
134 args.args_count = 1;
135 args.args[0] = id;
136
137 return of_clk_get_from_provider(&args);
138 }
139
ingenic_tcu_setup_cevt(unsigned int cpu)140 static int ingenic_tcu_setup_cevt(unsigned int cpu)
141 {
142 struct ingenic_tcu *tcu = ingenic_tcu;
143 struct ingenic_tcu_timer *timer = &tcu->timers[cpu];
144 unsigned int timer_virq;
145 struct irq_domain *domain;
146 unsigned long rate;
147 int err;
148
149 timer->clk = ingenic_tcu_get_clock(tcu->np, timer->channel);
150 if (IS_ERR(timer->clk))
151 return PTR_ERR(timer->clk);
152
153 err = clk_prepare_enable(timer->clk);
154 if (err)
155 goto err_clk_put;
156
157 rate = clk_get_rate(timer->clk);
158 if (!rate) {
159 err = -EINVAL;
160 goto err_clk_disable;
161 }
162
163 domain = irq_find_host(tcu->np);
164 if (!domain) {
165 err = -ENODEV;
166 goto err_clk_disable;
167 }
168
169 timer_virq = irq_create_mapping(domain, timer->channel);
170 if (!timer_virq) {
171 err = -EINVAL;
172 goto err_clk_disable;
173 }
174
175 snprintf(timer->name, sizeof(timer->name), "TCU%u", timer->channel);
176
177 err = request_irq(timer_virq, ingenic_tcu_cevt_cb, IRQF_TIMER,
178 timer->name, timer);
179 if (err)
180 goto err_irq_dispose_mapping;
181
182 timer->cpu = smp_processor_id();
183 timer->cevt.cpumask = cpumask_of(smp_processor_id());
184 timer->cevt.features = CLOCK_EVT_FEAT_ONESHOT;
185 timer->cevt.name = timer->name;
186 timer->cevt.rating = 200;
187 timer->cevt.set_state_shutdown = ingenic_tcu_cevt_set_state_shutdown;
188 timer->cevt.set_next_event = ingenic_tcu_cevt_set_next;
189
190 clockevents_config_and_register(&timer->cevt, rate, 10, 0xffff);
191
192 return 0;
193
194 err_irq_dispose_mapping:
195 irq_dispose_mapping(timer_virq);
196 err_clk_disable:
197 clk_disable_unprepare(timer->clk);
198 err_clk_put:
199 clk_put(timer->clk);
200 return err;
201 }
202
ingenic_tcu_clocksource_init(struct device_node * np,struct ingenic_tcu * tcu)203 static int __init ingenic_tcu_clocksource_init(struct device_node *np,
204 struct ingenic_tcu *tcu)
205 {
206 unsigned int channel = tcu->cs_channel;
207 struct clocksource *cs = &tcu->cs;
208 unsigned long rate;
209 int err;
210
211 tcu->cs_clk = ingenic_tcu_get_clock(np, channel);
212 if (IS_ERR(tcu->cs_clk))
213 return PTR_ERR(tcu->cs_clk);
214
215 err = clk_prepare_enable(tcu->cs_clk);
216 if (err)
217 goto err_clk_put;
218
219 rate = clk_get_rate(tcu->cs_clk);
220 if (!rate) {
221 err = -EINVAL;
222 goto err_clk_disable;
223 }
224
225 /* Reset channel */
226 regmap_update_bits(tcu->map, TCU_REG_TCSRc(channel),
227 0xffff & ~TCU_TCSR_RESERVED_BITS, 0);
228
229 /* Reset counter */
230 regmap_write(tcu->map, TCU_REG_TDFRc(channel), 0xffff);
231 regmap_write(tcu->map, TCU_REG_TCNTc(channel), 0);
232
233 /* Enable channel */
234 regmap_write(tcu->map, TCU_REG_TESR, BIT(channel));
235
236 cs->name = "ingenic-timer";
237 cs->rating = 200;
238 cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
239 cs->mask = CLOCKSOURCE_MASK(16);
240 cs->read = ingenic_tcu_timer_cs_read;
241
242 err = clocksource_register_hz(cs, rate);
243 if (err)
244 goto err_clk_disable;
245
246 return 0;
247
248 err_clk_disable:
249 clk_disable_unprepare(tcu->cs_clk);
250 err_clk_put:
251 clk_put(tcu->cs_clk);
252 return err;
253 }
254
255 static const struct ingenic_soc_info jz4740_soc_info = {
256 .num_channels = 8,
257 };
258
259 static const struct ingenic_soc_info jz4725b_soc_info = {
260 .num_channels = 6,
261 };
262
263 static const struct of_device_id ingenic_tcu_of_match[] = {
264 { .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, },
265 { .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, },
266 { .compatible = "ingenic,jz4760-tcu", .data = &jz4740_soc_info, },
267 { .compatible = "ingenic,jz4770-tcu", .data = &jz4740_soc_info, },
268 { .compatible = "ingenic,x1000-tcu", .data = &jz4740_soc_info, },
269 { /* sentinel */ }
270 };
271
ingenic_tcu_init(struct device_node * np)272 static int __init ingenic_tcu_init(struct device_node *np)
273 {
274 const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np);
275 const struct ingenic_soc_info *soc_info = id->data;
276 struct ingenic_tcu_timer *timer;
277 struct ingenic_tcu *tcu;
278 struct regmap *map;
279 unsigned int cpu;
280 int ret, last_bit = -1;
281 long rate;
282
283 of_node_clear_flag(np, OF_POPULATED);
284
285 map = device_node_to_regmap(np);
286 if (IS_ERR(map))
287 return PTR_ERR(map);
288
289 tcu = kzalloc(struct_size(tcu, timers, num_possible_cpus()),
290 GFP_KERNEL);
291 if (!tcu)
292 return -ENOMEM;
293
294 /*
295 * Enable all TCU channels for PWM use by default except channels 0/1,
296 * and channel 2 if target CPU is JZ4780/X2000 and SMP is selected.
297 */
298 tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1,
299 num_possible_cpus() + 1);
300 of_property_read_u32(np, "ingenic,pwm-channels-mask",
301 (u32 *)&tcu->pwm_channels_mask);
302
303 /* Verify that we have at least num_possible_cpus() + 1 free channels */
304 if (hweight8(tcu->pwm_channels_mask) >
305 soc_info->num_channels - num_possible_cpus() + 1) {
306 pr_crit("%s: Invalid PWM channel mask: 0x%02lx\n", __func__,
307 tcu->pwm_channels_mask);
308 ret = -EINVAL;
309 goto err_free_ingenic_tcu;
310 }
311
312 tcu->map = map;
313 tcu->np = np;
314 ingenic_tcu = tcu;
315
316 for (cpu = 0; cpu < num_possible_cpus(); cpu++) {
317 timer = &tcu->timers[cpu];
318
319 timer->cpu = cpu;
320 timer->channel = find_next_zero_bit(&tcu->pwm_channels_mask,
321 soc_info->num_channels,
322 last_bit + 1);
323 last_bit = timer->channel;
324 }
325
326 tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask,
327 soc_info->num_channels,
328 last_bit + 1);
329
330 ret = ingenic_tcu_clocksource_init(np, tcu);
331 if (ret) {
332 pr_crit("%s: Unable to init clocksource: %d\n", __func__, ret);
333 goto err_free_ingenic_tcu;
334 }
335
336 /* Setup clock events on each CPU core */
337 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "Ingenic XBurst: online",
338 ingenic_tcu_setup_cevt, NULL);
339 if (ret < 0) {
340 pr_crit("%s: Unable to start CPU timers: %d\n", __func__, ret);
341 goto err_tcu_clocksource_cleanup;
342 }
343
344 /* Register the sched_clock at the end as there's no way to undo it */
345 rate = clk_get_rate(tcu->cs_clk);
346 sched_clock_register(ingenic_tcu_timer_read, 16, rate);
347
348 return 0;
349
350 err_tcu_clocksource_cleanup:
351 clocksource_unregister(&tcu->cs);
352 clk_disable_unprepare(tcu->cs_clk);
353 clk_put(tcu->cs_clk);
354 err_free_ingenic_tcu:
355 kfree(tcu);
356 return ret;
357 }
358
359 TIMER_OF_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu", ingenic_tcu_init);
360 TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", ingenic_tcu_init);
361 TIMER_OF_DECLARE(jz4760_tcu_intc, "ingenic,jz4760-tcu", ingenic_tcu_init);
362 TIMER_OF_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu", ingenic_tcu_init);
363 TIMER_OF_DECLARE(x1000_tcu_intc, "ingenic,x1000-tcu", ingenic_tcu_init);
364
ingenic_tcu_probe(struct platform_device * pdev)365 static int __init ingenic_tcu_probe(struct platform_device *pdev)
366 {
367 platform_set_drvdata(pdev, ingenic_tcu);
368
369 return 0;
370 }
371
ingenic_tcu_suspend(struct device * dev)372 static int ingenic_tcu_suspend(struct device *dev)
373 {
374 struct ingenic_tcu *tcu = dev_get_drvdata(dev);
375 unsigned int cpu;
376
377 clk_disable(tcu->cs_clk);
378
379 for (cpu = 0; cpu < num_online_cpus(); cpu++)
380 clk_disable(tcu->timers[cpu].clk);
381
382 return 0;
383 }
384
ingenic_tcu_resume(struct device * dev)385 static int ingenic_tcu_resume(struct device *dev)
386 {
387 struct ingenic_tcu *tcu = dev_get_drvdata(dev);
388 unsigned int cpu;
389 int ret;
390
391 for (cpu = 0; cpu < num_online_cpus(); cpu++) {
392 ret = clk_enable(tcu->timers[cpu].clk);
393 if (ret)
394 goto err_timer_clk_disable;
395 }
396
397 ret = clk_enable(tcu->cs_clk);
398 if (ret)
399 goto err_timer_clk_disable;
400
401 return 0;
402
403 err_timer_clk_disable:
404 for (; cpu > 0; cpu--)
405 clk_disable(tcu->timers[cpu - 1].clk);
406 return ret;
407 }
408
409 static const struct dev_pm_ops ingenic_tcu_pm_ops = {
410 /* _noirq: We want the TCU clocks to be gated last / ungated first */
411 .suspend_noirq = ingenic_tcu_suspend,
412 .resume_noirq = ingenic_tcu_resume,
413 };
414
415 static struct platform_driver ingenic_tcu_driver = {
416 .driver = {
417 .name = "ingenic-tcu-timer",
418 .pm = pm_sleep_ptr(&ingenic_tcu_pm_ops),
419 .of_match_table = ingenic_tcu_of_match,
420 },
421 };
422 builtin_platform_driver_probe(ingenic_tcu_driver, ingenic_tcu_probe);
423