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/interrupt.h>
13 #include <linux/mfd/ingenic-tcu.h>
14 #include <linux/mfd/syscon.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_platform.h>
19 #include <linux/overflow.h>
20 #include <linux/platform_device.h>
21 #include <linux/regmap.h>
22 #include <linux/sched_clock.h>
23
24 #include <dt-bindings/clock/ingenic,tcu.h>
25
26 static DEFINE_PER_CPU(call_single_data_t, ingenic_cevt_csd);
27
28 struct ingenic_soc_info {
29 unsigned int num_channels;
30 };
31
32 struct ingenic_tcu_timer {
33 unsigned int cpu;
34 unsigned int channel;
35 struct clock_event_device cevt;
36 struct clk *clk;
37 char name[8];
38 };
39
40 struct ingenic_tcu {
41 struct regmap *map;
42 struct device_node *np;
43 struct clk *cs_clk;
44 unsigned int cs_channel;
45 struct clocksource cs;
46 unsigned long pwm_channels_mask;
47 struct ingenic_tcu_timer timers[];
48 };
49
50 static struct ingenic_tcu *ingenic_tcu;
51
ingenic_tcu_timer_read(void)52 static u64 notrace ingenic_tcu_timer_read(void)
53 {
54 struct ingenic_tcu *tcu = ingenic_tcu;
55 unsigned int count;
56
57 regmap_read(tcu->map, TCU_REG_TCNTc(tcu->cs_channel), &count);
58
59 return count;
60 }
61
ingenic_tcu_timer_cs_read(struct clocksource * cs)62 static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource *cs)
63 {
64 return ingenic_tcu_timer_read();
65 }
66
67 static inline struct ingenic_tcu *
to_ingenic_tcu(struct ingenic_tcu_timer * timer)68 to_ingenic_tcu(struct ingenic_tcu_timer *timer)
69 {
70 return container_of(timer, struct ingenic_tcu, timers[timer->cpu]);
71 }
72
73 static inline struct ingenic_tcu_timer *
to_ingenic_tcu_timer(struct clock_event_device * evt)74 to_ingenic_tcu_timer(struct clock_event_device *evt)
75 {
76 return container_of(evt, struct ingenic_tcu_timer, cevt);
77 }
78
ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device * evt)79 static int ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device *evt)
80 {
81 struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt);
82 struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
83
84 regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel));
85
86 return 0;
87 }
88
ingenic_tcu_cevt_set_next(unsigned long next,struct clock_event_device * evt)89 static int ingenic_tcu_cevt_set_next(unsigned long next,
90 struct clock_event_device *evt)
91 {
92 struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt);
93 struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
94
95 if (next > 0xffff)
96 return -EINVAL;
97
98 regmap_write(tcu->map, TCU_REG_TDFRc(timer->channel), next);
99 regmap_write(tcu->map, TCU_REG_TCNTc(timer->channel), 0);
100 regmap_write(tcu->map, TCU_REG_TESR, BIT(timer->channel));
101
102 return 0;
103 }
104
ingenic_per_cpu_event_handler(void * info)105 static void ingenic_per_cpu_event_handler(void *info)
106 {
107 struct clock_event_device *cevt = (struct clock_event_device *) info;
108
109 cevt->event_handler(cevt);
110 }
111
ingenic_tcu_cevt_cb(int irq,void * dev_id)112 static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id)
113 {
114 struct ingenic_tcu_timer *timer = dev_id;
115 struct ingenic_tcu *tcu = to_ingenic_tcu(timer);
116 call_single_data_t *csd;
117
118 regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel));
119
120 if (timer->cevt.event_handler) {
121 csd = &per_cpu(ingenic_cevt_csd, timer->cpu);
122 csd->info = (void *) &timer->cevt;
123 csd->func = ingenic_per_cpu_event_handler;
124 smp_call_function_single_async(timer->cpu, csd);
125 }
126
127 return IRQ_HANDLED;
128 }
129
ingenic_tcu_get_clock(struct device_node * np,int id)130 static struct clk *ingenic_tcu_get_clock(struct device_node *np, int id)
131 {
132 struct of_phandle_args args;
133
134 args.np = np;
135 args.args_count = 1;
136 args.args[0] = id;
137
138 return of_clk_get_from_provider(&args);
139 }
140
ingenic_tcu_setup_cevt(unsigned int cpu)141 static int ingenic_tcu_setup_cevt(unsigned int cpu)
142 {
143 struct ingenic_tcu *tcu = ingenic_tcu;
144 struct ingenic_tcu_timer *timer = &tcu->timers[cpu];
145 unsigned int timer_virq;
146 struct irq_domain *domain;
147 unsigned long rate;
148 int err;
149
150 timer->clk = ingenic_tcu_get_clock(tcu->np, timer->channel);
151 if (IS_ERR(timer->clk))
152 return PTR_ERR(timer->clk);
153
154 err = clk_prepare_enable(timer->clk);
155 if (err)
156 goto err_clk_put;
157
158 rate = clk_get_rate(timer->clk);
159 if (!rate) {
160 err = -EINVAL;
161 goto err_clk_disable;
162 }
163
164 domain = irq_find_host(tcu->np);
165 if (!domain) {
166 err = -ENODEV;
167 goto err_clk_disable;
168 }
169
170 timer_virq = irq_create_mapping(domain, timer->channel);
171 if (!timer_virq) {
172 err = -EINVAL;
173 goto err_clk_disable;
174 }
175
176 snprintf(timer->name, sizeof(timer->name), "TCU%u", timer->channel);
177
178 err = request_irq(timer_virq, ingenic_tcu_cevt_cb, IRQF_TIMER,
179 timer->name, timer);
180 if (err)
181 goto err_irq_dispose_mapping;
182
183 timer->cpu = smp_processor_id();
184 timer->cevt.cpumask = cpumask_of(smp_processor_id());
185 timer->cevt.features = CLOCK_EVT_FEAT_ONESHOT;
186 timer->cevt.name = timer->name;
187 timer->cevt.rating = 200;
188 timer->cevt.set_state_shutdown = ingenic_tcu_cevt_set_state_shutdown;
189 timer->cevt.set_next_event = ingenic_tcu_cevt_set_next;
190
191 clockevents_config_and_register(&timer->cevt, rate, 10, 0xffff);
192
193 return 0;
194
195 err_irq_dispose_mapping:
196 irq_dispose_mapping(timer_virq);
197 err_clk_disable:
198 clk_disable_unprepare(timer->clk);
199 err_clk_put:
200 clk_put(timer->clk);
201 return err;
202 }
203
ingenic_tcu_clocksource_init(struct device_node * np,struct ingenic_tcu * tcu)204 static int __init ingenic_tcu_clocksource_init(struct device_node *np,
205 struct ingenic_tcu *tcu)
206 {
207 unsigned int channel = tcu->cs_channel;
208 struct clocksource *cs = &tcu->cs;
209 unsigned long rate;
210 int err;
211
212 tcu->cs_clk = ingenic_tcu_get_clock(np, channel);
213 if (IS_ERR(tcu->cs_clk))
214 return PTR_ERR(tcu->cs_clk);
215
216 err = clk_prepare_enable(tcu->cs_clk);
217 if (err)
218 goto err_clk_put;
219
220 rate = clk_get_rate(tcu->cs_clk);
221 if (!rate) {
222 err = -EINVAL;
223 goto err_clk_disable;
224 }
225
226 /* Reset channel */
227 regmap_update_bits(tcu->map, TCU_REG_TCSRc(channel),
228 0xffff & ~TCU_TCSR_RESERVED_BITS, 0);
229
230 /* Reset counter */
231 regmap_write(tcu->map, TCU_REG_TDFRc(channel), 0xffff);
232 regmap_write(tcu->map, TCU_REG_TCNTc(channel), 0);
233
234 /* Enable channel */
235 regmap_write(tcu->map, TCU_REG_TESR, BIT(channel));
236
237 cs->name = "ingenic-timer";
238 cs->rating = 200;
239 cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
240 cs->mask = CLOCKSOURCE_MASK(16);
241 cs->read = ingenic_tcu_timer_cs_read;
242
243 err = clocksource_register_hz(cs, rate);
244 if (err)
245 goto err_clk_disable;
246
247 return 0;
248
249 err_clk_disable:
250 clk_disable_unprepare(tcu->cs_clk);
251 err_clk_put:
252 clk_put(tcu->cs_clk);
253 return err;
254 }
255
256 static const struct ingenic_soc_info jz4740_soc_info = {
257 .num_channels = 8,
258 };
259
260 static const struct ingenic_soc_info jz4725b_soc_info = {
261 .num_channels = 6,
262 };
263
264 static const struct of_device_id ingenic_tcu_of_match[] = {
265 { .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, },
266 { .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, },
267 { .compatible = "ingenic,jz4760-tcu", .data = &jz4740_soc_info, },
268 { .compatible = "ingenic,jz4770-tcu", .data = &jz4740_soc_info, },
269 { .compatible = "ingenic,x1000-tcu", .data = &jz4740_soc_info, },
270 { /* sentinel */ }
271 };
272
ingenic_tcu_init(struct device_node * np)273 static int __init ingenic_tcu_init(struct device_node *np)
274 {
275 const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np);
276 const struct ingenic_soc_info *soc_info = id->data;
277 struct ingenic_tcu_timer *timer;
278 struct ingenic_tcu *tcu;
279 struct regmap *map;
280 unsigned int cpu;
281 int ret, last_bit = -1;
282 long rate;
283
284 of_node_clear_flag(np, OF_POPULATED);
285
286 map = device_node_to_regmap(np);
287 if (IS_ERR(map))
288 return PTR_ERR(map);
289
290 tcu = kzalloc(struct_size(tcu, timers, num_possible_cpus()),
291 GFP_KERNEL);
292 if (!tcu)
293 return -ENOMEM;
294
295 /*
296 * Enable all TCU channels for PWM use by default except channels 0/1,
297 * and channel 2 if target CPU is JZ4780/X2000 and SMP is selected.
298 */
299 tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1,
300 num_possible_cpus() + 1);
301 of_property_read_u32(np, "ingenic,pwm-channels-mask",
302 (u32 *)&tcu->pwm_channels_mask);
303
304 /* Verify that we have at least num_possible_cpus() + 1 free channels */
305 if (hweight8(tcu->pwm_channels_mask) >
306 soc_info->num_channels - num_possible_cpus() + 1) {
307 pr_crit("%s: Invalid PWM channel mask: 0x%02lx\n", __func__,
308 tcu->pwm_channels_mask);
309 ret = -EINVAL;
310 goto err_free_ingenic_tcu;
311 }
312
313 tcu->map = map;
314 tcu->np = np;
315 ingenic_tcu = tcu;
316
317 for (cpu = 0; cpu < num_possible_cpus(); cpu++) {
318 timer = &tcu->timers[cpu];
319
320 timer->cpu = cpu;
321 timer->channel = find_next_zero_bit(&tcu->pwm_channels_mask,
322 soc_info->num_channels,
323 last_bit + 1);
324 last_bit = timer->channel;
325 }
326
327 tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask,
328 soc_info->num_channels,
329 last_bit + 1);
330
331 ret = ingenic_tcu_clocksource_init(np, tcu);
332 if (ret) {
333 pr_crit("%s: Unable to init clocksource: %d\n", __func__, ret);
334 goto err_free_ingenic_tcu;
335 }
336
337 /* Setup clock events on each CPU core */
338 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "Ingenic XBurst: online",
339 ingenic_tcu_setup_cevt, NULL);
340 if (ret < 0) {
341 pr_crit("%s: Unable to start CPU timers: %d\n", __func__, ret);
342 goto err_tcu_clocksource_cleanup;
343 }
344
345 /* Register the sched_clock at the end as there's no way to undo it */
346 rate = clk_get_rate(tcu->cs_clk);
347 sched_clock_register(ingenic_tcu_timer_read, 16, rate);
348
349 return 0;
350
351 err_tcu_clocksource_cleanup:
352 clocksource_unregister(&tcu->cs);
353 clk_disable_unprepare(tcu->cs_clk);
354 clk_put(tcu->cs_clk);
355 err_free_ingenic_tcu:
356 kfree(tcu);
357 return ret;
358 }
359
360 TIMER_OF_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu", ingenic_tcu_init);
361 TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", ingenic_tcu_init);
362 TIMER_OF_DECLARE(jz4760_tcu_intc, "ingenic,jz4760-tcu", ingenic_tcu_init);
363 TIMER_OF_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu", ingenic_tcu_init);
364 TIMER_OF_DECLARE(x1000_tcu_intc, "ingenic,x1000-tcu", ingenic_tcu_init);
365
ingenic_tcu_probe(struct platform_device * pdev)366 static int __init ingenic_tcu_probe(struct platform_device *pdev)
367 {
368 platform_set_drvdata(pdev, ingenic_tcu);
369
370 return 0;
371 }
372
ingenic_tcu_suspend(struct device * dev)373 static int __maybe_unused ingenic_tcu_suspend(struct device *dev)
374 {
375 struct ingenic_tcu *tcu = dev_get_drvdata(dev);
376 unsigned int cpu;
377
378 clk_disable(tcu->cs_clk);
379
380 for (cpu = 0; cpu < num_online_cpus(); cpu++)
381 clk_disable(tcu->timers[cpu].clk);
382
383 return 0;
384 }
385
ingenic_tcu_resume(struct device * dev)386 static int __maybe_unused ingenic_tcu_resume(struct device *dev)
387 {
388 struct ingenic_tcu *tcu = dev_get_drvdata(dev);
389 unsigned int cpu;
390 int ret;
391
392 for (cpu = 0; cpu < num_online_cpus(); cpu++) {
393 ret = clk_enable(tcu->timers[cpu].clk);
394 if (ret)
395 goto err_timer_clk_disable;
396 }
397
398 ret = clk_enable(tcu->cs_clk);
399 if (ret)
400 goto err_timer_clk_disable;
401
402 return 0;
403
404 err_timer_clk_disable:
405 for (; cpu > 0; cpu--)
406 clk_disable(tcu->timers[cpu - 1].clk);
407 return ret;
408 }
409
410 static const struct dev_pm_ops __maybe_unused ingenic_tcu_pm_ops = {
411 /* _noirq: We want the TCU clocks to be gated last / ungated first */
412 .suspend_noirq = ingenic_tcu_suspend,
413 .resume_noirq = ingenic_tcu_resume,
414 };
415
416 static struct platform_driver ingenic_tcu_driver = {
417 .driver = {
418 .name = "ingenic-tcu-timer",
419 #ifdef CONFIG_PM_SLEEP
420 .pm = &ingenic_tcu_pm_ops,
421 #endif
422 .of_match_table = ingenic_tcu_of_match,
423 },
424 };
425 builtin_platform_driver_probe(ingenic_tcu_driver, ingenic_tcu_probe);
426