dm thin metadata: fix __udivdi3 undefined on 32-bit
[linux/fpc-iii.git] / drivers / clocksource / exynos_mct.c
blob47f8aafe33441a6dbf5c34cd9e3a853833cef5dc
1 /* linux/arch/arm/mach-exynos4/mct.c
3 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4 * http://www.samsung.com
6 * EXYNOS4 MCT(Multi-Core Timer) support
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/sched.h>
14 #include <linux/interrupt.h>
15 #include <linux/irq.h>
16 #include <linux/err.h>
17 #include <linux/clk.h>
18 #include <linux/clockchips.h>
19 #include <linux/cpu.h>
20 #include <linux/platform_device.h>
21 #include <linux/delay.h>
22 #include <linux/percpu.h>
23 #include <linux/of.h>
24 #include <linux/of_irq.h>
25 #include <linux/of_address.h>
26 #include <linux/clocksource.h>
27 #include <linux/sched_clock.h>
29 #define EXYNOS4_MCTREG(x) (x)
30 #define EXYNOS4_MCT_G_CNT_L EXYNOS4_MCTREG(0x100)
31 #define EXYNOS4_MCT_G_CNT_U EXYNOS4_MCTREG(0x104)
32 #define EXYNOS4_MCT_G_CNT_WSTAT EXYNOS4_MCTREG(0x110)
33 #define EXYNOS4_MCT_G_COMP0_L EXYNOS4_MCTREG(0x200)
34 #define EXYNOS4_MCT_G_COMP0_U EXYNOS4_MCTREG(0x204)
35 #define EXYNOS4_MCT_G_COMP0_ADD_INCR EXYNOS4_MCTREG(0x208)
36 #define EXYNOS4_MCT_G_TCON EXYNOS4_MCTREG(0x240)
37 #define EXYNOS4_MCT_G_INT_CSTAT EXYNOS4_MCTREG(0x244)
38 #define EXYNOS4_MCT_G_INT_ENB EXYNOS4_MCTREG(0x248)
39 #define EXYNOS4_MCT_G_WSTAT EXYNOS4_MCTREG(0x24C)
40 #define _EXYNOS4_MCT_L_BASE EXYNOS4_MCTREG(0x300)
41 #define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * x))
42 #define EXYNOS4_MCT_L_MASK (0xffffff00)
44 #define MCT_L_TCNTB_OFFSET (0x00)
45 #define MCT_L_ICNTB_OFFSET (0x08)
46 #define MCT_L_TCON_OFFSET (0x20)
47 #define MCT_L_INT_CSTAT_OFFSET (0x30)
48 #define MCT_L_INT_ENB_OFFSET (0x34)
49 #define MCT_L_WSTAT_OFFSET (0x40)
50 #define MCT_G_TCON_START (1 << 8)
51 #define MCT_G_TCON_COMP0_AUTO_INC (1 << 1)
52 #define MCT_G_TCON_COMP0_ENABLE (1 << 0)
53 #define MCT_L_TCON_INTERVAL_MODE (1 << 2)
54 #define MCT_L_TCON_INT_START (1 << 1)
55 #define MCT_L_TCON_TIMER_START (1 << 0)
57 #define TICK_BASE_CNT 1
59 enum {
60 MCT_INT_SPI,
61 MCT_INT_PPI
64 enum {
65 MCT_G0_IRQ,
66 MCT_G1_IRQ,
67 MCT_G2_IRQ,
68 MCT_G3_IRQ,
69 MCT_L0_IRQ,
70 MCT_L1_IRQ,
71 MCT_L2_IRQ,
72 MCT_L3_IRQ,
73 MCT_L4_IRQ,
74 MCT_L5_IRQ,
75 MCT_L6_IRQ,
76 MCT_L7_IRQ,
77 MCT_NR_IRQS,
80 static void __iomem *reg_base;
81 static unsigned long clk_rate;
82 static unsigned int mct_int_type;
83 static int mct_irqs[MCT_NR_IRQS];
85 struct mct_clock_event_device {
86 struct clock_event_device evt;
87 unsigned long base;
88 char name[10];
91 static void exynos4_mct_write(unsigned int value, unsigned long offset)
93 unsigned long stat_addr;
94 u32 mask;
95 u32 i;
97 writel_relaxed(value, reg_base + offset);
99 if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) {
100 stat_addr = (offset & EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET;
101 switch (offset & ~EXYNOS4_MCT_L_MASK) {
102 case MCT_L_TCON_OFFSET:
103 mask = 1 << 3; /* L_TCON write status */
104 break;
105 case MCT_L_ICNTB_OFFSET:
106 mask = 1 << 1; /* L_ICNTB write status */
107 break;
108 case MCT_L_TCNTB_OFFSET:
109 mask = 1 << 0; /* L_TCNTB write status */
110 break;
111 default:
112 return;
114 } else {
115 switch (offset) {
116 case EXYNOS4_MCT_G_TCON:
117 stat_addr = EXYNOS4_MCT_G_WSTAT;
118 mask = 1 << 16; /* G_TCON write status */
119 break;
120 case EXYNOS4_MCT_G_COMP0_L:
121 stat_addr = EXYNOS4_MCT_G_WSTAT;
122 mask = 1 << 0; /* G_COMP0_L write status */
123 break;
124 case EXYNOS4_MCT_G_COMP0_U:
125 stat_addr = EXYNOS4_MCT_G_WSTAT;
126 mask = 1 << 1; /* G_COMP0_U write status */
127 break;
128 case EXYNOS4_MCT_G_COMP0_ADD_INCR:
129 stat_addr = EXYNOS4_MCT_G_WSTAT;
130 mask = 1 << 2; /* G_COMP0_ADD_INCR w status */
131 break;
132 case EXYNOS4_MCT_G_CNT_L:
133 stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
134 mask = 1 << 0; /* G_CNT_L write status */
135 break;
136 case EXYNOS4_MCT_G_CNT_U:
137 stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
138 mask = 1 << 1; /* G_CNT_U write status */
139 break;
140 default:
141 return;
145 /* Wait maximum 1 ms until written values are applied */
146 for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++)
147 if (readl_relaxed(reg_base + stat_addr) & mask) {
148 writel_relaxed(mask, reg_base + stat_addr);
149 return;
152 panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset);
155 /* Clocksource handling */
156 static void exynos4_mct_frc_start(void)
158 u32 reg;
160 reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
161 reg |= MCT_G_TCON_START;
162 exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
166 * exynos4_read_count_64 - Read all 64-bits of the global counter
168 * This will read all 64-bits of the global counter taking care to make sure
169 * that the upper and lower half match. Note that reading the MCT can be quite
170 * slow (hundreds of nanoseconds) so you should use the 32-bit (lower half
171 * only) version when possible.
173 * Returns the number of cycles in the global counter.
175 static u64 exynos4_read_count_64(void)
177 unsigned int lo, hi;
178 u32 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
180 do {
181 hi = hi2;
182 lo = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
183 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
184 } while (hi != hi2);
186 return ((cycle_t)hi << 32) | lo;
190 * exynos4_read_count_32 - Read the lower 32-bits of the global counter
192 * This will read just the lower 32-bits of the global counter. This is marked
193 * as notrace so it can be used by the scheduler clock.
195 * Returns the number of cycles in the global counter (lower 32 bits).
197 static u32 notrace exynos4_read_count_32(void)
199 return readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
202 static cycle_t exynos4_frc_read(struct clocksource *cs)
204 return exynos4_read_count_32();
207 static void exynos4_frc_resume(struct clocksource *cs)
209 exynos4_mct_frc_start();
212 static struct clocksource mct_frc = {
213 .name = "mct-frc",
214 .rating = 400,
215 .read = exynos4_frc_read,
216 .mask = CLOCKSOURCE_MASK(32),
217 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
218 .resume = exynos4_frc_resume,
221 static u64 notrace exynos4_read_sched_clock(void)
223 return exynos4_read_count_32();
226 static struct delay_timer exynos4_delay_timer;
228 static cycles_t exynos4_read_current_timer(void)
230 BUILD_BUG_ON_MSG(sizeof(cycles_t) != sizeof(u32),
231 "cycles_t needs to move to 32-bit for ARM64 usage");
232 return exynos4_read_count_32();
235 static void __init exynos4_clocksource_init(void)
237 exynos4_mct_frc_start();
239 exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer;
240 exynos4_delay_timer.freq = clk_rate;
241 register_current_timer_delay(&exynos4_delay_timer);
243 if (clocksource_register_hz(&mct_frc, clk_rate))
244 panic("%s: can't register clocksource\n", mct_frc.name);
246 sched_clock_register(exynos4_read_sched_clock, 32, clk_rate);
249 static void exynos4_mct_comp0_stop(void)
251 unsigned int tcon;
253 tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
254 tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC);
256 exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON);
257 exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB);
260 static void exynos4_mct_comp0_start(bool periodic, unsigned long cycles)
262 unsigned int tcon;
263 cycle_t comp_cycle;
265 tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
267 if (periodic) {
268 tcon |= MCT_G_TCON_COMP0_AUTO_INC;
269 exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
272 comp_cycle = exynos4_read_count_64() + cycles;
273 exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L);
274 exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U);
276 exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB);
278 tcon |= MCT_G_TCON_COMP0_ENABLE;
279 exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON);
282 static int exynos4_comp_set_next_event(unsigned long cycles,
283 struct clock_event_device *evt)
285 exynos4_mct_comp0_start(false, cycles);
287 return 0;
290 static int mct_set_state_shutdown(struct clock_event_device *evt)
292 exynos4_mct_comp0_stop();
293 return 0;
296 static int mct_set_state_periodic(struct clock_event_device *evt)
298 unsigned long cycles_per_jiffy;
300 cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
301 >> evt->shift);
302 exynos4_mct_comp0_stop();
303 exynos4_mct_comp0_start(true, cycles_per_jiffy);
304 return 0;
307 static struct clock_event_device mct_comp_device = {
308 .name = "mct-comp",
309 .features = CLOCK_EVT_FEAT_PERIODIC |
310 CLOCK_EVT_FEAT_ONESHOT,
311 .rating = 250,
312 .set_next_event = exynos4_comp_set_next_event,
313 .set_state_periodic = mct_set_state_periodic,
314 .set_state_shutdown = mct_set_state_shutdown,
315 .set_state_oneshot = mct_set_state_shutdown,
316 .tick_resume = mct_set_state_shutdown,
319 static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id)
321 struct clock_event_device *evt = dev_id;
323 exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT);
325 evt->event_handler(evt);
327 return IRQ_HANDLED;
330 static struct irqaction mct_comp_event_irq = {
331 .name = "mct_comp_irq",
332 .flags = IRQF_TIMER | IRQF_IRQPOLL,
333 .handler = exynos4_mct_comp_isr,
334 .dev_id = &mct_comp_device,
337 static void exynos4_clockevent_init(void)
339 mct_comp_device.cpumask = cpumask_of(0);
340 clockevents_config_and_register(&mct_comp_device, clk_rate,
341 0xf, 0xffffffff);
342 setup_irq(mct_irqs[MCT_G0_IRQ], &mct_comp_event_irq);
345 static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick);
347 /* Clock event handling */
348 static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt)
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;
354 tmp = readl_relaxed(reg_base + offset);
355 if (tmp & mask) {
356 tmp &= ~mask;
357 exynos4_mct_write(tmp, offset);
361 static void exynos4_mct_tick_start(unsigned long cycles,
362 struct mct_clock_event_device *mevt)
364 unsigned long tmp;
366 exynos4_mct_tick_stop(mevt);
368 tmp = (1 << 31) | cycles; /* MCT_L_UPDATE_ICNTB */
370 /* update interrupt count buffer */
371 exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET);
373 /* enable MCT tick interrupt */
374 exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET);
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);
382 static int exynos4_tick_set_next_event(unsigned long cycles,
383 struct clock_event_device *evt)
385 struct mct_clock_event_device *mevt;
387 mevt = container_of(evt, struct mct_clock_event_device, evt);
388 exynos4_mct_tick_start(cycles, mevt);
389 return 0;
392 static int set_state_shutdown(struct clock_event_device *evt)
394 struct mct_clock_event_device *mevt;
396 mevt = container_of(evt, struct mct_clock_event_device, evt);
397 exynos4_mct_tick_stop(mevt);
398 return 0;
401 static int set_state_periodic(struct clock_event_device *evt)
403 struct mct_clock_event_device *mevt;
404 unsigned long cycles_per_jiffy;
406 mevt = container_of(evt, struct mct_clock_event_device, evt);
407 cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
408 >> evt->shift);
409 exynos4_mct_tick_stop(mevt);
410 exynos4_mct_tick_start(cycles_per_jiffy, mevt);
411 return 0;
414 static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
417 * This is for supporting oneshot mode.
418 * Mct would generate interrupt periodically
419 * without explicit stopping.
421 if (!clockevent_state_periodic(&mevt->evt))
422 exynos4_mct_tick_stop(mevt);
424 /* Clear the MCT tick interrupt */
425 if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
426 exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
429 static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
431 struct mct_clock_event_device *mevt = dev_id;
432 struct clock_event_device *evt = &mevt->evt;
434 exynos4_mct_tick_clear(mevt);
436 evt->event_handler(evt);
438 return IRQ_HANDLED;
441 static int exynos4_local_timer_setup(struct mct_clock_event_device *mevt)
443 struct clock_event_device *evt = &mevt->evt;
444 unsigned int cpu = smp_processor_id();
446 mevt->base = EXYNOS4_MCT_L_BASE(cpu);
447 snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);
449 evt->name = mevt->name;
450 evt->cpumask = cpumask_of(cpu);
451 evt->set_next_event = exynos4_tick_set_next_event;
452 evt->set_state_periodic = set_state_periodic;
453 evt->set_state_shutdown = set_state_shutdown;
454 evt->set_state_oneshot = set_state_shutdown;
455 evt->tick_resume = set_state_shutdown;
456 evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
457 evt->rating = 450;
459 exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
461 if (mct_int_type == MCT_INT_SPI) {
463 if (evt->irq == -1)
464 return -EIO;
466 irq_force_affinity(evt->irq, cpumask_of(cpu));
467 enable_irq(evt->irq);
468 } else {
469 enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
471 clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
472 0xf, 0x7fffffff);
474 return 0;
477 static void exynos4_local_timer_stop(struct mct_clock_event_device *mevt)
479 struct clock_event_device *evt = &mevt->evt;
481 evt->set_state_shutdown(evt);
482 if (mct_int_type == MCT_INT_SPI) {
483 if (evt->irq != -1)
484 disable_irq_nosync(evt->irq);
485 exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
486 } else {
487 disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
491 static int exynos4_mct_cpu_notify(struct notifier_block *self,
492 unsigned long action, void *hcpu)
494 struct mct_clock_event_device *mevt;
497 * Grab cpu pointer in each case to avoid spurious
498 * preemptible warnings
500 switch (action & ~CPU_TASKS_FROZEN) {
501 case CPU_STARTING:
502 mevt = this_cpu_ptr(&percpu_mct_tick);
503 exynos4_local_timer_setup(mevt);
504 break;
505 case CPU_DYING:
506 mevt = this_cpu_ptr(&percpu_mct_tick);
507 exynos4_local_timer_stop(mevt);
508 break;
511 return NOTIFY_OK;
514 static struct notifier_block exynos4_mct_cpu_nb = {
515 .notifier_call = exynos4_mct_cpu_notify,
518 static void __init exynos4_timer_resources(struct device_node *np, void __iomem *base)
520 int err, cpu;
521 struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
522 struct clk *mct_clk, *tick_clk;
524 tick_clk = np ? of_clk_get_by_name(np, "fin_pll") :
525 clk_get(NULL, "fin_pll");
526 if (IS_ERR(tick_clk))
527 panic("%s: unable to determine tick clock rate\n", __func__);
528 clk_rate = clk_get_rate(tick_clk);
530 mct_clk = np ? of_clk_get_by_name(np, "mct") : clk_get(NULL, "mct");
531 if (IS_ERR(mct_clk))
532 panic("%s: unable to retrieve mct clock instance\n", __func__);
533 clk_prepare_enable(mct_clk);
535 reg_base = base;
536 if (!reg_base)
537 panic("%s: unable to ioremap mct address space\n", __func__);
539 if (mct_int_type == MCT_INT_PPI) {
541 err = request_percpu_irq(mct_irqs[MCT_L0_IRQ],
542 exynos4_mct_tick_isr, "MCT",
543 &percpu_mct_tick);
544 WARN(err, "MCT: can't request IRQ %d (%d)\n",
545 mct_irqs[MCT_L0_IRQ], err);
546 } else {
547 for_each_possible_cpu(cpu) {
548 int mct_irq = mct_irqs[MCT_L0_IRQ + cpu];
549 struct mct_clock_event_device *pcpu_mevt =
550 per_cpu_ptr(&percpu_mct_tick, cpu);
552 pcpu_mevt->evt.irq = -1;
554 irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);
555 if (request_irq(mct_irq,
556 exynos4_mct_tick_isr,
557 IRQF_TIMER | IRQF_NOBALANCING,
558 pcpu_mevt->name, pcpu_mevt)) {
559 pr_err("exynos-mct: cannot register IRQ (cpu%d)\n",
560 cpu);
562 continue;
564 pcpu_mevt->evt.irq = mct_irq;
568 err = register_cpu_notifier(&exynos4_mct_cpu_nb);
569 if (err)
570 goto out_irq;
572 /* Immediately configure the timer on the boot CPU */
573 exynos4_local_timer_setup(mevt);
574 return;
576 out_irq:
577 free_percpu_irq(mct_irqs[MCT_L0_IRQ], &percpu_mct_tick);
580 static void __init mct_init_dt(struct device_node *np, unsigned int int_type)
582 u32 nr_irqs, i;
584 mct_int_type = int_type;
586 /* This driver uses only one global timer interrupt */
587 mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
590 * Find out the number of local irqs specified. The local
591 * timer irqs are specified after the four global timer
592 * irqs are specified.
594 #ifdef CONFIG_OF
595 nr_irqs = of_irq_count(np);
596 #else
597 nr_irqs = 0;
598 #endif
599 for (i = MCT_L0_IRQ; i < nr_irqs; i++)
600 mct_irqs[i] = irq_of_parse_and_map(np, i);
602 exynos4_timer_resources(np, of_iomap(np, 0));
603 exynos4_clocksource_init();
604 exynos4_clockevent_init();
608 static void __init mct_init_spi(struct device_node *np)
610 return mct_init_dt(np, MCT_INT_SPI);
613 static void __init mct_init_ppi(struct device_node *np)
615 return mct_init_dt(np, MCT_INT_PPI);
617 CLOCKSOURCE_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi);
618 CLOCKSOURCE_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi);