1 // SPDX-License-Identifier: GPL-2.0-only
2 /* linux/arch/arm/mach-exynos4/mct.c
3  *
4  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
5  *		http://www.samsung.com
6  *
7  * Exynos4 MCT(Multi-Core Timer) support
8 */
9 
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/err.h>
13 #include <linux/clk.h>
14 #include <linux/clockchips.h>
15 #include <linux/cpu.h>
16 #include <linux/delay.h>
17 #include <linux/percpu.h>
18 #include <linux/of.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_address.h>
21 #include <linux/clocksource.h>
22 #include <linux/sched_clock.h>
23 
24 #define EXYNOS4_MCTREG(x)		(x)
25 #define EXYNOS4_MCT_G_CNT_L		EXYNOS4_MCTREG(0x100)
26 #define EXYNOS4_MCT_G_CNT_U		EXYNOS4_MCTREG(0x104)
27 #define EXYNOS4_MCT_G_CNT_WSTAT		EXYNOS4_MCTREG(0x110)
28 #define EXYNOS4_MCT_G_COMP0_L		EXYNOS4_MCTREG(0x200)
29 #define EXYNOS4_MCT_G_COMP0_U		EXYNOS4_MCTREG(0x204)
30 #define EXYNOS4_MCT_G_COMP0_ADD_INCR	EXYNOS4_MCTREG(0x208)
31 #define EXYNOS4_MCT_G_TCON		EXYNOS4_MCTREG(0x240)
32 #define EXYNOS4_MCT_G_INT_CSTAT		EXYNOS4_MCTREG(0x244)
33 #define EXYNOS4_MCT_G_INT_ENB		EXYNOS4_MCTREG(0x248)
34 #define EXYNOS4_MCT_G_WSTAT		EXYNOS4_MCTREG(0x24C)
35 #define _EXYNOS4_MCT_L_BASE		EXYNOS4_MCTREG(0x300)
36 #define EXYNOS4_MCT_L_BASE(x)		(_EXYNOS4_MCT_L_BASE + (0x100 * x))
37 #define EXYNOS4_MCT_L_MASK		(0xffffff00)
38 
39 #define MCT_L_TCNTB_OFFSET		(0x00)
40 #define MCT_L_ICNTB_OFFSET		(0x08)
41 #define MCT_L_TCON_OFFSET		(0x20)
42 #define MCT_L_INT_CSTAT_OFFSET		(0x30)
43 #define MCT_L_INT_ENB_OFFSET		(0x34)
44 #define MCT_L_WSTAT_OFFSET		(0x40)
45 #define MCT_G_TCON_START		(1 << 8)
46 #define MCT_G_TCON_COMP0_AUTO_INC	(1 << 1)
47 #define MCT_G_TCON_COMP0_ENABLE		(1 << 0)
48 #define MCT_L_TCON_INTERVAL_MODE	(1 << 2)
49 #define MCT_L_TCON_INT_START		(1 << 1)
50 #define MCT_L_TCON_TIMER_START		(1 << 0)
51 
52 #define TICK_BASE_CNT	1
53 
54 enum {
55 	MCT_INT_SPI,
56 	MCT_INT_PPI
57 };
58 
59 enum {
60 	MCT_G0_IRQ,
61 	MCT_G1_IRQ,
62 	MCT_G2_IRQ,
63 	MCT_G3_IRQ,
64 	MCT_L0_IRQ,
65 	MCT_L1_IRQ,
66 	MCT_L2_IRQ,
67 	MCT_L3_IRQ,
68 	MCT_L4_IRQ,
69 	MCT_L5_IRQ,
70 	MCT_L6_IRQ,
71 	MCT_L7_IRQ,
72 	MCT_NR_IRQS,
73 };
74 
75 static void __iomem *reg_base;
76 static unsigned long clk_rate;
77 static unsigned int mct_int_type;
78 static int mct_irqs[MCT_NR_IRQS];
79 
80 struct mct_clock_event_device {
81 	struct clock_event_device evt;
82 	unsigned long base;
83 	char name[10];
84 };
85 
exynos4_mct_write(unsigned int value,unsigned long offset)86 static void exynos4_mct_write(unsigned int value, unsigned long offset)
87 {
88 	unsigned long stat_addr;
89 	u32 mask;
90 	u32 i;
91 
92 	writel_relaxed(value, reg_base + offset);
93 
94 	if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) {
95 		stat_addr = (offset & EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET;
96 		switch (offset & ~EXYNOS4_MCT_L_MASK) {
97 		case MCT_L_TCON_OFFSET:
98 			mask = 1 << 3;		/* L_TCON write status */
99 			break;
100 		case MCT_L_ICNTB_OFFSET:
101 			mask = 1 << 1;		/* L_ICNTB write status */
102 			break;
103 		case MCT_L_TCNTB_OFFSET:
104 			mask = 1 << 0;		/* L_TCNTB write status */
105 			break;
106 		default:
107 			return;
108 		}
109 	} else {
110 		switch (offset) {
111 		case EXYNOS4_MCT_G_TCON:
112 			stat_addr = EXYNOS4_MCT_G_WSTAT;
113 			mask = 1 << 16;		/* G_TCON write status */
114 			break;
115 		case EXYNOS4_MCT_G_COMP0_L:
116 			stat_addr = EXYNOS4_MCT_G_WSTAT;
117 			mask = 1 << 0;		/* G_COMP0_L write status */
118 			break;
119 		case EXYNOS4_MCT_G_COMP0_U:
120 			stat_addr = EXYNOS4_MCT_G_WSTAT;
121 			mask = 1 << 1;		/* G_COMP0_U write status */
122 			break;
123 		case EXYNOS4_MCT_G_COMP0_ADD_INCR:
124 			stat_addr = EXYNOS4_MCT_G_WSTAT;
125 			mask = 1 << 2;		/* G_COMP0_ADD_INCR w status */
126 			break;
127 		case EXYNOS4_MCT_G_CNT_L:
128 			stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
129 			mask = 1 << 0;		/* G_CNT_L write status */
130 			break;
131 		case EXYNOS4_MCT_G_CNT_U:
132 			stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
133 			mask = 1 << 1;		/* G_CNT_U write status */
134 			break;
135 		default:
136 			return;
137 		}
138 	}
139 
140 	/* Wait maximum 1 ms until written values are applied */
141 	for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++)
142 		if (readl_relaxed(reg_base + stat_addr) & mask) {
143 			writel_relaxed(mask, reg_base + stat_addr);
144 			return;
145 		}
146 
147 	panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset);
148 }
149 
150 /* Clocksource handling */
exynos4_mct_frc_start(void)151 static void exynos4_mct_frc_start(void)
152 {
153 	u32 reg;
154 
155 	reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
156 	reg |= MCT_G_TCON_START;
157 	exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
158 }
159 
160 /**
161  * exynos4_read_count_64 - Read all 64-bits of the global counter
162  *
163  * This will read all 64-bits of the global counter taking care to make sure
164  * that the upper and lower half match.  Note that reading the MCT can be quite
165  * slow (hundreds of nanoseconds) so you should use the 32-bit (lower half
166  * only) version when possible.
167  *
168  * Returns the number of cycles in the global counter.
169  */
exynos4_read_count_64(void)170 static u64 exynos4_read_count_64(void)
171 {
172 	unsigned int lo, hi;
173 	u32 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
174 
175 	do {
176 		hi = hi2;
177 		lo = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
178 		hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
179 	} while (hi != hi2);
180 
181 	return ((u64)hi << 32) | lo;
182 }
183 
184 /**
185  * exynos4_read_count_32 - Read the lower 32-bits of the global counter
186  *
187  * This will read just the lower 32-bits of the global counter.  This is marked
188  * as notrace so it can be used by the scheduler clock.
189  *
190  * Returns the number of cycles in the global counter (lower 32 bits).
191  */
exynos4_read_count_32(void)192 static u32 notrace exynos4_read_count_32(void)
193 {
194 	return readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
195 }
196 
exynos4_frc_read(struct clocksource * cs)197 static u64 exynos4_frc_read(struct clocksource *cs)
198 {
199 	return exynos4_read_count_32();
200 }
201 
exynos4_frc_resume(struct clocksource * cs)202 static void exynos4_frc_resume(struct clocksource *cs)
203 {
204 	exynos4_mct_frc_start();
205 }
206 
207 static struct clocksource mct_frc = {
208 	.name		= "mct-frc",
209 	.rating		= 450,	/* use value higher than ARM arch timer */
210 	.read		= exynos4_frc_read,
211 	.mask		= CLOCKSOURCE_MASK(32),
212 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
213 	.resume		= exynos4_frc_resume,
214 };
215 
exynos4_read_sched_clock(void)216 static u64 notrace exynos4_read_sched_clock(void)
217 {
218 	return exynos4_read_count_32();
219 }
220 
221 #if defined(CONFIG_ARM)
222 static struct delay_timer exynos4_delay_timer;
223 
exynos4_read_current_timer(void)224 static cycles_t exynos4_read_current_timer(void)
225 {
226 	BUILD_BUG_ON_MSG(sizeof(cycles_t) != sizeof(u32),
227 			 "cycles_t needs to move to 32-bit for ARM64 usage");
228 	return exynos4_read_count_32();
229 }
230 #endif
231 
exynos4_clocksource_init(void)232 static int __init exynos4_clocksource_init(void)
233 {
234 	exynos4_mct_frc_start();
235 
236 #if defined(CONFIG_ARM)
237 	exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer;
238 	exynos4_delay_timer.freq = clk_rate;
239 	register_current_timer_delay(&exynos4_delay_timer);
240 #endif
241 
242 	if (clocksource_register_hz(&mct_frc, clk_rate))
243 		panic("%s: can't register clocksource\n", mct_frc.name);
244 
245 	sched_clock_register(exynos4_read_sched_clock, 32, clk_rate);
246 
247 	return 0;
248 }
249 
exynos4_mct_comp0_stop(void)250 static void exynos4_mct_comp0_stop(void)
251 {
252 	unsigned int tcon;
253 
254 	tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
255 	tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC);
256 
257 	exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON);
258 	exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB);
259 }
260 
exynos4_mct_comp0_start(bool periodic,unsigned long cycles)261 static void exynos4_mct_comp0_start(bool periodic, unsigned long cycles)
262 {
263 	unsigned int tcon;
264 	u64 comp_cycle;
265 
266 	tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
267 
268 	if (periodic) {
269 		tcon |= MCT_G_TCON_COMP0_AUTO_INC;
270 		exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
271 	}
272 
273 	comp_cycle = exynos4_read_count_64() + cycles;
274 	exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L);
275 	exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U);
276 
277 	exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB);
278 
279 	tcon |= MCT_G_TCON_COMP0_ENABLE;
280 	exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON);
281 }
282 
exynos4_comp_set_next_event(unsigned long cycles,struct clock_event_device * evt)283 static int exynos4_comp_set_next_event(unsigned long cycles,
284 				       struct clock_event_device *evt)
285 {
286 	exynos4_mct_comp0_start(false, cycles);
287 
288 	return 0;
289 }
290 
mct_set_state_shutdown(struct clock_event_device * evt)291 static int mct_set_state_shutdown(struct clock_event_device *evt)
292 {
293 	exynos4_mct_comp0_stop();
294 	return 0;
295 }
296 
mct_set_state_periodic(struct clock_event_device * evt)297 static int mct_set_state_periodic(struct clock_event_device *evt)
298 {
299 	unsigned long cycles_per_jiffy;
300 
301 	cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
302 			    >> evt->shift);
303 	exynos4_mct_comp0_stop();
304 	exynos4_mct_comp0_start(true, cycles_per_jiffy);
305 	return 0;
306 }
307 
308 static struct clock_event_device mct_comp_device = {
309 	.name			= "mct-comp",
310 	.features		= CLOCK_EVT_FEAT_PERIODIC |
311 				  CLOCK_EVT_FEAT_ONESHOT,
312 	.rating			= 250,
313 	.set_next_event		= exynos4_comp_set_next_event,
314 	.set_state_periodic	= mct_set_state_periodic,
315 	.set_state_shutdown	= mct_set_state_shutdown,
316 	.set_state_oneshot	= mct_set_state_shutdown,
317 	.set_state_oneshot_stopped = mct_set_state_shutdown,
318 	.tick_resume		= mct_set_state_shutdown,
319 };
320 
exynos4_mct_comp_isr(int irq,void * dev_id)321 static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id)
322 {
323 	struct clock_event_device *evt = dev_id;
324 
325 	exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT);
326 
327 	evt->event_handler(evt);
328 
329 	return IRQ_HANDLED;
330 }
331 
exynos4_clockevent_init(void)332 static int exynos4_clockevent_init(void)
333 {
334 	mct_comp_device.cpumask = cpumask_of(0);
335 	clockevents_config_and_register(&mct_comp_device, clk_rate,
336 					0xf, 0xffffffff);
337 	if (request_irq(mct_irqs[MCT_G0_IRQ], exynos4_mct_comp_isr,
338 			IRQF_TIMER | IRQF_IRQPOLL, "mct_comp_irq",
339 			&mct_comp_device))
340 		pr_err("%s: request_irq() failed\n", "mct_comp_irq");
341 
342 	return 0;
343 }
344 
345 static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick);
346 
347 /* Clock event handling */
exynos4_mct_tick_stop(struct mct_clock_event_device * mevt)348 static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt)
349 {
350 	unsigned long tmp;
351 	unsigned long mask = MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START;
352 	unsigned long offset = mevt->base + MCT_L_TCON_OFFSET;
353 
354 	tmp = readl_relaxed(reg_base + offset);
355 	if (tmp & mask) {
356 		tmp &= ~mask;
357 		exynos4_mct_write(tmp, offset);
358 	}
359 }
360 
exynos4_mct_tick_start(unsigned long cycles,struct mct_clock_event_device * mevt)361 static void exynos4_mct_tick_start(unsigned long cycles,
362 				   struct mct_clock_event_device *mevt)
363 {
364 	unsigned long tmp;
365 
366 	exynos4_mct_tick_stop(mevt);
367 
368 	tmp = (1 << 31) | cycles;	/* MCT_L_UPDATE_ICNTB */
369 
370 	/* update interrupt count buffer */
371 	exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET);
372 
373 	/* enable MCT tick interrupt */
374 	exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET);
375 
376 	tmp = readl_relaxed(reg_base + mevt->base + MCT_L_TCON_OFFSET);
377 	tmp |= MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START |
378 	       MCT_L_TCON_INTERVAL_MODE;
379 	exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET);
380 }
381 
exynos4_mct_tick_clear(struct mct_clock_event_device * mevt)382 static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
383 {
384 	/* Clear the MCT tick interrupt */
385 	if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
386 		exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
387 }
388 
exynos4_tick_set_next_event(unsigned long cycles,struct clock_event_device * evt)389 static int exynos4_tick_set_next_event(unsigned long cycles,
390 				       struct clock_event_device *evt)
391 {
392 	struct mct_clock_event_device *mevt;
393 
394 	mevt = container_of(evt, struct mct_clock_event_device, evt);
395 	exynos4_mct_tick_start(cycles, mevt);
396 	return 0;
397 }
398 
set_state_shutdown(struct clock_event_device * evt)399 static int set_state_shutdown(struct clock_event_device *evt)
400 {
401 	struct mct_clock_event_device *mevt;
402 
403 	mevt = container_of(evt, struct mct_clock_event_device, evt);
404 	exynos4_mct_tick_stop(mevt);
405 	exynos4_mct_tick_clear(mevt);
406 	return 0;
407 }
408 
set_state_periodic(struct clock_event_device * evt)409 static int set_state_periodic(struct clock_event_device *evt)
410 {
411 	struct mct_clock_event_device *mevt;
412 	unsigned long cycles_per_jiffy;
413 
414 	mevt = container_of(evt, struct mct_clock_event_device, evt);
415 	cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
416 			    >> evt->shift);
417 	exynos4_mct_tick_stop(mevt);
418 	exynos4_mct_tick_start(cycles_per_jiffy, mevt);
419 	return 0;
420 }
421 
exynos4_mct_tick_isr(int irq,void * dev_id)422 static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
423 {
424 	struct mct_clock_event_device *mevt = dev_id;
425 	struct clock_event_device *evt = &mevt->evt;
426 
427 	/*
428 	 * This is for supporting oneshot mode.
429 	 * Mct would generate interrupt periodically
430 	 * without explicit stopping.
431 	 */
432 	if (!clockevent_state_periodic(&mevt->evt))
433 		exynos4_mct_tick_stop(mevt);
434 
435 	exynos4_mct_tick_clear(mevt);
436 
437 	evt->event_handler(evt);
438 
439 	return IRQ_HANDLED;
440 }
441 
exynos4_mct_starting_cpu(unsigned int cpu)442 static int exynos4_mct_starting_cpu(unsigned int cpu)
443 {
444 	struct mct_clock_event_device *mevt =
445 		per_cpu_ptr(&percpu_mct_tick, cpu);
446 	struct clock_event_device *evt = &mevt->evt;
447 
448 	mevt->base = EXYNOS4_MCT_L_BASE(cpu);
449 	snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);
450 
451 	evt->name = mevt->name;
452 	evt->cpumask = cpumask_of(cpu);
453 	evt->set_next_event = exynos4_tick_set_next_event;
454 	evt->set_state_periodic = set_state_periodic;
455 	evt->set_state_shutdown = set_state_shutdown;
456 	evt->set_state_oneshot = set_state_shutdown;
457 	evt->set_state_oneshot_stopped = set_state_shutdown;
458 	evt->tick_resume = set_state_shutdown;
459 	evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
460 	evt->rating = 500;	/* use value higher than ARM arch timer */
461 
462 	exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
463 
464 	if (mct_int_type == MCT_INT_SPI) {
465 
466 		if (evt->irq == -1)
467 			return -EIO;
468 
469 		irq_force_affinity(evt->irq, cpumask_of(cpu));
470 		enable_irq(evt->irq);
471 	} else {
472 		enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
473 	}
474 	clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
475 					0xf, 0x7fffffff);
476 
477 	return 0;
478 }
479 
exynos4_mct_dying_cpu(unsigned int cpu)480 static int exynos4_mct_dying_cpu(unsigned int cpu)
481 {
482 	struct mct_clock_event_device *mevt =
483 		per_cpu_ptr(&percpu_mct_tick, cpu);
484 	struct clock_event_device *evt = &mevt->evt;
485 
486 	evt->set_state_shutdown(evt);
487 	if (mct_int_type == MCT_INT_SPI) {
488 		if (evt->irq != -1)
489 			disable_irq_nosync(evt->irq);
490 		exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
491 	} else {
492 		disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
493 	}
494 	return 0;
495 }
496 
exynos4_timer_resources(struct device_node * np,void __iomem * base)497 static int __init exynos4_timer_resources(struct device_node *np, void __iomem *base)
498 {
499 	int err, cpu;
500 	struct clk *mct_clk, *tick_clk;
501 
502 	tick_clk = of_clk_get_by_name(np, "fin_pll");
503 	if (IS_ERR(tick_clk))
504 		panic("%s: unable to determine tick clock rate\n", __func__);
505 	clk_rate = clk_get_rate(tick_clk);
506 
507 	mct_clk = of_clk_get_by_name(np, "mct");
508 	if (IS_ERR(mct_clk))
509 		panic("%s: unable to retrieve mct clock instance\n", __func__);
510 	clk_prepare_enable(mct_clk);
511 
512 	reg_base = base;
513 	if (!reg_base)
514 		panic("%s: unable to ioremap mct address space\n", __func__);
515 
516 	if (mct_int_type == MCT_INT_PPI) {
517 
518 		err = request_percpu_irq(mct_irqs[MCT_L0_IRQ],
519 					 exynos4_mct_tick_isr, "MCT",
520 					 &percpu_mct_tick);
521 		WARN(err, "MCT: can't request IRQ %d (%d)\n",
522 		     mct_irqs[MCT_L0_IRQ], err);
523 	} else {
524 		for_each_possible_cpu(cpu) {
525 			int mct_irq = mct_irqs[MCT_L0_IRQ + cpu];
526 			struct mct_clock_event_device *pcpu_mevt =
527 				per_cpu_ptr(&percpu_mct_tick, cpu);
528 
529 			pcpu_mevt->evt.irq = -1;
530 
531 			irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);
532 			if (request_irq(mct_irq,
533 					exynos4_mct_tick_isr,
534 					IRQF_TIMER | IRQF_NOBALANCING,
535 					pcpu_mevt->name, pcpu_mevt)) {
536 				pr_err("exynos-mct: cannot register IRQ (cpu%d)\n",
537 									cpu);
538 
539 				continue;
540 			}
541 			pcpu_mevt->evt.irq = mct_irq;
542 		}
543 	}
544 
545 	/* Install hotplug callbacks which configure the timer on this CPU */
546 	err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
547 				"clockevents/exynos4/mct_timer:starting",
548 				exynos4_mct_starting_cpu,
549 				exynos4_mct_dying_cpu);
550 	if (err)
551 		goto out_irq;
552 
553 	return 0;
554 
555 out_irq:
556 	if (mct_int_type == MCT_INT_PPI) {
557 		free_percpu_irq(mct_irqs[MCT_L0_IRQ], &percpu_mct_tick);
558 	} else {
559 		for_each_possible_cpu(cpu) {
560 			struct mct_clock_event_device *pcpu_mevt =
561 				per_cpu_ptr(&percpu_mct_tick, cpu);
562 
563 			if (pcpu_mevt->evt.irq != -1) {
564 				free_irq(pcpu_mevt->evt.irq, pcpu_mevt);
565 				pcpu_mevt->evt.irq = -1;
566 			}
567 		}
568 	}
569 	return err;
570 }
571 
mct_init_dt(struct device_node * np,unsigned int int_type)572 static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
573 {
574 	u32 nr_irqs, i;
575 	int ret;
576 
577 	mct_int_type = int_type;
578 
579 	/* This driver uses only one global timer interrupt */
580 	mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
581 
582 	/*
583 	 * Find out the number of local irqs specified. The local
584 	 * timer irqs are specified after the four global timer
585 	 * irqs are specified.
586 	 */
587 	nr_irqs = of_irq_count(np);
588 	for (i = MCT_L0_IRQ; i < nr_irqs; i++)
589 		mct_irqs[i] = irq_of_parse_and_map(np, i);
590 
591 	ret = exynos4_timer_resources(np, of_iomap(np, 0));
592 	if (ret)
593 		return ret;
594 
595 	ret = exynos4_clocksource_init();
596 	if (ret)
597 		return ret;
598 
599 	return exynos4_clockevent_init();
600 }
601 
602 
mct_init_spi(struct device_node * np)603 static int __init mct_init_spi(struct device_node *np)
604 {
605 	return mct_init_dt(np, MCT_INT_SPI);
606 }
607 
mct_init_ppi(struct device_node * np)608 static int __init mct_init_ppi(struct device_node *np)
609 {
610 	return mct_init_dt(np, MCT_INT_PPI);
611 }
612 TIMER_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi);
613 TIMER_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi);
614