1 // SPDX-License-Identifier: GPL-2.0
3 * SuperH Timer Support - CMT
5 * Copyright (C) 2008 Magnus Damm
9 #include <linux/clockchips.h>
10 #include <linux/clocksource.h>
11 #include <linux/delay.h>
12 #include <linux/err.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
16 #include <linux/iopoll.h>
17 #include <linux/ioport.h>
18 #include <linux/irq.h>
19 #include <linux/module.h>
21 #include <linux/of_device.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_domain.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/sh_timer.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
30 #include <asm/platform_early.h>
36 * The CMT comes in 5 different identified flavours, depending not only on the
37 * SoC but also on the particular instance. The following table lists the main
38 * characteristics of those flavours.
40 * 16B 32B 32B-F 48B R-Car Gen2
41 * -----------------------------------------------------------------------------
42 * Channels 2 1/4 1 6 2/8
43 * Control Width 16 16 16 16 32
44 * Counter Width 16 32 32 32/48 32/48
45 * Shared Start/Stop Y Y Y Y N
47 * The r8a73a4 / R-Car Gen2 version has a per-channel start/stop register
48 * located in the channel registers block. All other versions have a shared
49 * start/stop register located in the global space.
51 * Channels are indexed from 0 to N-1 in the documentation. The channel index
52 * infers the start/stop bit position in the control register and the channel
53 * registers block address. Some CMT instances have a subset of channels
54 * available, in which case the index in the documentation doesn't match the
55 * "real" index as implemented in hardware. This is for instance the case with
56 * CMT0 on r8a7740, which is a 32-bit variant with a single channel numbered 0
57 * in the documentation but using start/stop bit 5 and having its registers
60 * Similarly CMT0 on r8a73a4, r8a7790 and r8a7791, while implementing 32-bit
61 * channels only, is a 48-bit gen2 CMT with the 48-bit channels unavailable.
73 enum sh_cmt_model model;
75 unsigned int channels_mask;
77 unsigned long width; /* 16 or 32 bit version of hardware block */
81 /* callbacks for CMSTR and CMCSR access */
82 u32 (*read_control)(void __iomem *base, unsigned long offs);
83 void (*write_control)(void __iomem *base, unsigned long offs,
86 /* callbacks for CMCNT and CMCOR access */
87 u32 (*read_count)(void __iomem *base, unsigned long offs);
88 void (*write_count)(void __iomem *base, unsigned long offs, u32 value);
91 struct sh_cmt_channel {
92 struct sh_cmt_device *cmt;
94 unsigned int index; /* Index in the documentation */
95 unsigned int hwidx; /* Real hardware index */
97 void __iomem *iostart;
100 unsigned int timer_bit;
103 u32 next_match_value;
106 struct clock_event_device ced;
107 struct clocksource cs;
112 struct sh_cmt_device {
113 struct platform_device *pdev;
115 const struct sh_cmt_info *info;
117 void __iomem *mapbase;
120 unsigned int reg_delay;
122 raw_spinlock_t lock; /* Protect the shared start/stop register */
124 struct sh_cmt_channel *channels;
125 unsigned int num_channels;
126 unsigned int hw_channels;
129 bool has_clocksource;
132 #define SH_CMT16_CMCSR_CMF (1 << 7)
133 #define SH_CMT16_CMCSR_CMIE (1 << 6)
134 #define SH_CMT16_CMCSR_CKS8 (0 << 0)
135 #define SH_CMT16_CMCSR_CKS32 (1 << 0)
136 #define SH_CMT16_CMCSR_CKS128 (2 << 0)
137 #define SH_CMT16_CMCSR_CKS512 (3 << 0)
138 #define SH_CMT16_CMCSR_CKS_MASK (3 << 0)
140 #define SH_CMT32_CMCSR_CMF (1 << 15)
141 #define SH_CMT32_CMCSR_OVF (1 << 14)
142 #define SH_CMT32_CMCSR_WRFLG (1 << 13)
143 #define SH_CMT32_CMCSR_STTF (1 << 12)
144 #define SH_CMT32_CMCSR_STPF (1 << 11)
145 #define SH_CMT32_CMCSR_SSIE (1 << 10)
146 #define SH_CMT32_CMCSR_CMS (1 << 9)
147 #define SH_CMT32_CMCSR_CMM (1 << 8)
148 #define SH_CMT32_CMCSR_CMTOUT_IE (1 << 7)
149 #define SH_CMT32_CMCSR_CMR_NONE (0 << 4)
150 #define SH_CMT32_CMCSR_CMR_DMA (1 << 4)
151 #define SH_CMT32_CMCSR_CMR_IRQ (2 << 4)
152 #define SH_CMT32_CMCSR_CMR_MASK (3 << 4)
153 #define SH_CMT32_CMCSR_DBGIVD (1 << 3)
154 #define SH_CMT32_CMCSR_CKS_RCLK8 (4 << 0)
155 #define SH_CMT32_CMCSR_CKS_RCLK32 (5 << 0)
156 #define SH_CMT32_CMCSR_CKS_RCLK128 (6 << 0)
157 #define SH_CMT32_CMCSR_CKS_RCLK1 (7 << 0)
158 #define SH_CMT32_CMCSR_CKS_MASK (7 << 0)
160 static u32 sh_cmt_read16(void __iomem *base, unsigned long offs)
162 return ioread16(base + (offs << 1));
165 static u32 sh_cmt_read32(void __iomem *base, unsigned long offs)
167 return ioread32(base + (offs << 2));
170 static void sh_cmt_write16(void __iomem *base, unsigned long offs, u32 value)
172 iowrite16(value, base + (offs << 1));
175 static void sh_cmt_write32(void __iomem *base, unsigned long offs, u32 value)
177 iowrite32(value, base + (offs << 2));
180 static const struct sh_cmt_info sh_cmt_info[] = {
182 .model = SH_CMT_16BIT,
184 .overflow_bit = SH_CMT16_CMCSR_CMF,
185 .clear_bits = ~SH_CMT16_CMCSR_CMF,
186 .read_control = sh_cmt_read16,
187 .write_control = sh_cmt_write16,
188 .read_count = sh_cmt_read16,
189 .write_count = sh_cmt_write16,
192 .model = SH_CMT_32BIT,
194 .overflow_bit = SH_CMT32_CMCSR_CMF,
195 .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF),
196 .read_control = sh_cmt_read16,
197 .write_control = sh_cmt_write16,
198 .read_count = sh_cmt_read32,
199 .write_count = sh_cmt_write32,
202 .model = SH_CMT_48BIT,
203 .channels_mask = 0x3f,
205 .overflow_bit = SH_CMT32_CMCSR_CMF,
206 .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF),
207 .read_control = sh_cmt_read32,
208 .write_control = sh_cmt_write32,
209 .read_count = sh_cmt_read32,
210 .write_count = sh_cmt_write32,
212 [SH_CMT0_RCAR_GEN2] = {
213 .model = SH_CMT0_RCAR_GEN2,
214 .channels_mask = 0x60,
216 .overflow_bit = SH_CMT32_CMCSR_CMF,
217 .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF),
218 .read_control = sh_cmt_read32,
219 .write_control = sh_cmt_write32,
220 .read_count = sh_cmt_read32,
221 .write_count = sh_cmt_write32,
223 [SH_CMT1_RCAR_GEN2] = {
224 .model = SH_CMT1_RCAR_GEN2,
225 .channels_mask = 0xff,
227 .overflow_bit = SH_CMT32_CMCSR_CMF,
228 .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF),
229 .read_control = sh_cmt_read32,
230 .write_control = sh_cmt_write32,
231 .read_count = sh_cmt_read32,
232 .write_count = sh_cmt_write32,
236 #define CMCSR 0 /* channel register */
237 #define CMCNT 1 /* channel register */
238 #define CMCOR 2 /* channel register */
240 #define CMCLKE 0x1000 /* CLK Enable Register (R-Car Gen2) */
242 static inline u32 sh_cmt_read_cmstr(struct sh_cmt_channel *ch)
245 return ch->cmt->info->read_control(ch->iostart, 0);
247 return ch->cmt->info->read_control(ch->cmt->mapbase, 0);
250 static inline void sh_cmt_write_cmstr(struct sh_cmt_channel *ch, u32 value)
252 u32 old_value = sh_cmt_read_cmstr(ch);
254 if (value != old_value) {
256 ch->cmt->info->write_control(ch->iostart, 0, value);
257 udelay(ch->cmt->reg_delay);
259 ch->cmt->info->write_control(ch->cmt->mapbase, 0, value);
260 udelay(ch->cmt->reg_delay);
265 static inline u32 sh_cmt_read_cmcsr(struct sh_cmt_channel *ch)
267 return ch->cmt->info->read_control(ch->ioctrl, CMCSR);
270 static inline void sh_cmt_write_cmcsr(struct sh_cmt_channel *ch, u32 value)
272 u32 old_value = sh_cmt_read_cmcsr(ch);
274 if (value != old_value) {
275 ch->cmt->info->write_control(ch->ioctrl, CMCSR, value);
276 udelay(ch->cmt->reg_delay);
280 static inline u32 sh_cmt_read_cmcnt(struct sh_cmt_channel *ch)
282 return ch->cmt->info->read_count(ch->ioctrl, CMCNT);
285 static inline int sh_cmt_write_cmcnt(struct sh_cmt_channel *ch, u32 value)
287 /* Tests showed that we need to wait 3 clocks here */
288 unsigned int cmcnt_delay = DIV_ROUND_UP(3 * ch->cmt->reg_delay, 2);
291 if (ch->cmt->info->model > SH_CMT_16BIT) {
292 int ret = read_poll_timeout_atomic(sh_cmt_read_cmcsr, reg,
293 !(reg & SH_CMT32_CMCSR_WRFLG),
294 1, cmcnt_delay, false, ch);
299 ch->cmt->info->write_count(ch->ioctrl, CMCNT, value);
304 static inline void sh_cmt_write_cmcor(struct sh_cmt_channel *ch, u32 value)
306 u32 old_value = ch->cmt->info->read_count(ch->ioctrl, CMCOR);
308 if (value != old_value) {
309 ch->cmt->info->write_count(ch->ioctrl, CMCOR, value);
310 udelay(ch->cmt->reg_delay);
314 static u32 sh_cmt_get_counter(struct sh_cmt_channel *ch, u32 *has_wrapped)
319 o1 = sh_cmt_read_cmcsr(ch) & ch->cmt->info->overflow_bit;
321 /* Make sure the timer value is stable. Stolen from acpi_pm.c */
324 v1 = sh_cmt_read_cmcnt(ch);
325 v2 = sh_cmt_read_cmcnt(ch);
326 v3 = sh_cmt_read_cmcnt(ch);
327 o1 = sh_cmt_read_cmcsr(ch) & ch->cmt->info->overflow_bit;
328 } while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3)
329 || (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2)));
335 static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start)
340 /* start stop register shared by multiple timer channels */
341 raw_spin_lock_irqsave(&ch->cmt->lock, flags);
342 value = sh_cmt_read_cmstr(ch);
345 value |= 1 << ch->timer_bit;
347 value &= ~(1 << ch->timer_bit);
349 sh_cmt_write_cmstr(ch, value);
350 raw_spin_unlock_irqrestore(&ch->cmt->lock, flags);
353 static int sh_cmt_enable(struct sh_cmt_channel *ch)
357 pm_runtime_get_sync(&ch->cmt->pdev->dev);
358 dev_pm_syscore_device(&ch->cmt->pdev->dev, true);
361 ret = clk_enable(ch->cmt->clk);
363 dev_err(&ch->cmt->pdev->dev, "ch%u: cannot enable clock\n",
368 /* make sure channel is disabled */
369 sh_cmt_start_stop_ch(ch, 0);
371 /* configure channel, periodic mode and maximum timeout */
372 if (ch->cmt->info->width == 16) {
373 sh_cmt_write_cmcsr(ch, SH_CMT16_CMCSR_CMIE |
374 SH_CMT16_CMCSR_CKS512);
376 sh_cmt_write_cmcsr(ch, SH_CMT32_CMCSR_CMM |
377 SH_CMT32_CMCSR_CMTOUT_IE |
378 SH_CMT32_CMCSR_CMR_IRQ |
379 SH_CMT32_CMCSR_CKS_RCLK8);
382 sh_cmt_write_cmcor(ch, 0xffffffff);
383 ret = sh_cmt_write_cmcnt(ch, 0);
385 if (ret || sh_cmt_read_cmcnt(ch)) {
386 dev_err(&ch->cmt->pdev->dev, "ch%u: cannot clear CMCNT\n",
393 sh_cmt_start_stop_ch(ch, 1);
397 clk_disable(ch->cmt->clk);
403 static void sh_cmt_disable(struct sh_cmt_channel *ch)
405 /* disable channel */
406 sh_cmt_start_stop_ch(ch, 0);
408 /* disable interrupts in CMT block */
409 sh_cmt_write_cmcsr(ch, 0);
412 clk_disable(ch->cmt->clk);
414 dev_pm_syscore_device(&ch->cmt->pdev->dev, false);
415 pm_runtime_put(&ch->cmt->pdev->dev);
419 #define FLAG_CLOCKEVENT (1 << 0)
420 #define FLAG_CLOCKSOURCE (1 << 1)
421 #define FLAG_REPROGRAM (1 << 2)
422 #define FLAG_SKIPEVENT (1 << 3)
423 #define FLAG_IRQCONTEXT (1 << 4)
425 static void sh_cmt_clock_event_program_verify(struct sh_cmt_channel *ch,
428 u32 value = ch->next_match_value;
434 now = sh_cmt_get_counter(ch, &has_wrapped);
435 ch->flags |= FLAG_REPROGRAM; /* force reprogram */
438 /* we're competing with the interrupt handler.
439 * -> let the interrupt handler reprogram the timer.
440 * -> interrupt number two handles the event.
442 ch->flags |= FLAG_SKIPEVENT;
450 /* reprogram the timer hardware,
451 * but don't save the new match value yet.
453 new_match = now + value + delay;
454 if (new_match > ch->max_match_value)
455 new_match = ch->max_match_value;
457 sh_cmt_write_cmcor(ch, new_match);
459 now = sh_cmt_get_counter(ch, &has_wrapped);
460 if (has_wrapped && (new_match > ch->match_value)) {
461 /* we are changing to a greater match value,
462 * so this wrap must be caused by the counter
463 * matching the old value.
464 * -> first interrupt reprograms the timer.
465 * -> interrupt number two handles the event.
467 ch->flags |= FLAG_SKIPEVENT;
472 /* we are changing to a smaller match value,
473 * so the wrap must be caused by the counter
474 * matching the new value.
475 * -> save programmed match value.
476 * -> let isr handle the event.
478 ch->match_value = new_match;
482 /* be safe: verify hardware settings */
483 if (now < new_match) {
484 /* timer value is below match value, all good.
485 * this makes sure we won't miss any match events.
486 * -> save programmed match value.
487 * -> let isr handle the event.
489 ch->match_value = new_match;
493 /* the counter has reached a value greater
494 * than our new match value. and since the
495 * has_wrapped flag isn't set we must have
496 * programmed a too close event.
497 * -> increase delay and retry.
505 dev_warn(&ch->cmt->pdev->dev, "ch%u: too long delay\n",
511 static void __sh_cmt_set_next(struct sh_cmt_channel *ch, unsigned long delta)
513 if (delta > ch->max_match_value)
514 dev_warn(&ch->cmt->pdev->dev, "ch%u: delta out of range\n",
517 ch->next_match_value = delta;
518 sh_cmt_clock_event_program_verify(ch, 0);
521 static void sh_cmt_set_next(struct sh_cmt_channel *ch, unsigned long delta)
525 raw_spin_lock_irqsave(&ch->lock, flags);
526 __sh_cmt_set_next(ch, delta);
527 raw_spin_unlock_irqrestore(&ch->lock, flags);
530 static irqreturn_t sh_cmt_interrupt(int irq, void *dev_id)
532 struct sh_cmt_channel *ch = dev_id;
535 sh_cmt_write_cmcsr(ch, sh_cmt_read_cmcsr(ch) &
536 ch->cmt->info->clear_bits);
538 /* update clock source counter to begin with if enabled
539 * the wrap flag should be cleared by the timer specific
540 * isr before we end up here.
542 if (ch->flags & FLAG_CLOCKSOURCE)
543 ch->total_cycles += ch->match_value + 1;
545 if (!(ch->flags & FLAG_REPROGRAM))
546 ch->next_match_value = ch->max_match_value;
548 ch->flags |= FLAG_IRQCONTEXT;
550 if (ch->flags & FLAG_CLOCKEVENT) {
551 if (!(ch->flags & FLAG_SKIPEVENT)) {
552 if (clockevent_state_oneshot(&ch->ced)) {
553 ch->next_match_value = ch->max_match_value;
554 ch->flags |= FLAG_REPROGRAM;
557 ch->ced.event_handler(&ch->ced);
561 ch->flags &= ~FLAG_SKIPEVENT;
563 if (ch->flags & FLAG_REPROGRAM) {
564 ch->flags &= ~FLAG_REPROGRAM;
565 sh_cmt_clock_event_program_verify(ch, 1);
567 if (ch->flags & FLAG_CLOCKEVENT)
568 if ((clockevent_state_shutdown(&ch->ced))
569 || (ch->match_value == ch->next_match_value))
570 ch->flags &= ~FLAG_REPROGRAM;
573 ch->flags &= ~FLAG_IRQCONTEXT;
578 static int sh_cmt_start(struct sh_cmt_channel *ch, unsigned long flag)
583 raw_spin_lock_irqsave(&ch->lock, flags);
585 if (!(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE)))
586 ret = sh_cmt_enable(ch);
592 /* setup timeout if no clockevent */
593 if (ch->cmt->num_channels == 1 &&
594 flag == FLAG_CLOCKSOURCE && (!(ch->flags & FLAG_CLOCKEVENT)))
595 __sh_cmt_set_next(ch, ch->max_match_value);
597 raw_spin_unlock_irqrestore(&ch->lock, flags);
602 static void sh_cmt_stop(struct sh_cmt_channel *ch, unsigned long flag)
607 raw_spin_lock_irqsave(&ch->lock, flags);
609 f = ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE);
612 if (f && !(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE)))
615 /* adjust the timeout to maximum if only clocksource left */
616 if ((flag == FLAG_CLOCKEVENT) && (ch->flags & FLAG_CLOCKSOURCE))
617 __sh_cmt_set_next(ch, ch->max_match_value);
619 raw_spin_unlock_irqrestore(&ch->lock, flags);
622 static struct sh_cmt_channel *cs_to_sh_cmt(struct clocksource *cs)
624 return container_of(cs, struct sh_cmt_channel, cs);
627 static u64 sh_cmt_clocksource_read(struct clocksource *cs)
629 struct sh_cmt_channel *ch = cs_to_sh_cmt(cs);
632 if (ch->cmt->num_channels == 1) {
637 raw_spin_lock_irqsave(&ch->lock, flags);
638 value = ch->total_cycles;
639 raw = sh_cmt_get_counter(ch, &has_wrapped);
641 if (unlikely(has_wrapped))
642 raw += ch->match_value + 1;
643 raw_spin_unlock_irqrestore(&ch->lock, flags);
648 return sh_cmt_get_counter(ch, &has_wrapped);
651 static int sh_cmt_clocksource_enable(struct clocksource *cs)
654 struct sh_cmt_channel *ch = cs_to_sh_cmt(cs);
656 WARN_ON(ch->cs_enabled);
658 ch->total_cycles = 0;
660 ret = sh_cmt_start(ch, FLAG_CLOCKSOURCE);
662 ch->cs_enabled = true;
667 static void sh_cmt_clocksource_disable(struct clocksource *cs)
669 struct sh_cmt_channel *ch = cs_to_sh_cmt(cs);
671 WARN_ON(!ch->cs_enabled);
673 sh_cmt_stop(ch, FLAG_CLOCKSOURCE);
674 ch->cs_enabled = false;
677 static void sh_cmt_clocksource_suspend(struct clocksource *cs)
679 struct sh_cmt_channel *ch = cs_to_sh_cmt(cs);
684 sh_cmt_stop(ch, FLAG_CLOCKSOURCE);
685 pm_genpd_syscore_poweroff(&ch->cmt->pdev->dev);
688 static void sh_cmt_clocksource_resume(struct clocksource *cs)
690 struct sh_cmt_channel *ch = cs_to_sh_cmt(cs);
695 pm_genpd_syscore_poweron(&ch->cmt->pdev->dev);
696 sh_cmt_start(ch, FLAG_CLOCKSOURCE);
699 static int sh_cmt_register_clocksource(struct sh_cmt_channel *ch,
702 struct clocksource *cs = &ch->cs;
706 cs->read = sh_cmt_clocksource_read;
707 cs->enable = sh_cmt_clocksource_enable;
708 cs->disable = sh_cmt_clocksource_disable;
709 cs->suspend = sh_cmt_clocksource_suspend;
710 cs->resume = sh_cmt_clocksource_resume;
711 cs->mask = CLOCKSOURCE_MASK(ch->cmt->info->width);
712 cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
714 dev_info(&ch->cmt->pdev->dev, "ch%u: used as clock source\n",
717 clocksource_register_hz(cs, ch->cmt->rate);
721 static struct sh_cmt_channel *ced_to_sh_cmt(struct clock_event_device *ced)
723 return container_of(ced, struct sh_cmt_channel, ced);
726 static void sh_cmt_clock_event_start(struct sh_cmt_channel *ch, int periodic)
728 sh_cmt_start(ch, FLAG_CLOCKEVENT);
731 sh_cmt_set_next(ch, ((ch->cmt->rate + HZ/2) / HZ) - 1);
733 sh_cmt_set_next(ch, ch->max_match_value);
736 static int sh_cmt_clock_event_shutdown(struct clock_event_device *ced)
738 struct sh_cmt_channel *ch = ced_to_sh_cmt(ced);
740 sh_cmt_stop(ch, FLAG_CLOCKEVENT);
744 static int sh_cmt_clock_event_set_state(struct clock_event_device *ced,
747 struct sh_cmt_channel *ch = ced_to_sh_cmt(ced);
749 /* deal with old setting first */
750 if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced))
751 sh_cmt_stop(ch, FLAG_CLOCKEVENT);
753 dev_info(&ch->cmt->pdev->dev, "ch%u: used for %s clock events\n",
754 ch->index, periodic ? "periodic" : "oneshot");
755 sh_cmt_clock_event_start(ch, periodic);
759 static int sh_cmt_clock_event_set_oneshot(struct clock_event_device *ced)
761 return sh_cmt_clock_event_set_state(ced, 0);
764 static int sh_cmt_clock_event_set_periodic(struct clock_event_device *ced)
766 return sh_cmt_clock_event_set_state(ced, 1);
769 static int sh_cmt_clock_event_next(unsigned long delta,
770 struct clock_event_device *ced)
772 struct sh_cmt_channel *ch = ced_to_sh_cmt(ced);
774 BUG_ON(!clockevent_state_oneshot(ced));
775 if (likely(ch->flags & FLAG_IRQCONTEXT))
776 ch->next_match_value = delta - 1;
778 sh_cmt_set_next(ch, delta - 1);
783 static void sh_cmt_clock_event_suspend(struct clock_event_device *ced)
785 struct sh_cmt_channel *ch = ced_to_sh_cmt(ced);
787 pm_genpd_syscore_poweroff(&ch->cmt->pdev->dev);
788 clk_unprepare(ch->cmt->clk);
791 static void sh_cmt_clock_event_resume(struct clock_event_device *ced)
793 struct sh_cmt_channel *ch = ced_to_sh_cmt(ced);
795 clk_prepare(ch->cmt->clk);
796 pm_genpd_syscore_poweron(&ch->cmt->pdev->dev);
799 static int sh_cmt_register_clockevent(struct sh_cmt_channel *ch,
802 struct clock_event_device *ced = &ch->ced;
806 irq = platform_get_irq(ch->cmt->pdev, ch->index);
810 ret = request_irq(irq, sh_cmt_interrupt,
811 IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
812 dev_name(&ch->cmt->pdev->dev), ch);
814 dev_err(&ch->cmt->pdev->dev, "ch%u: failed to request irq %d\n",
820 ced->features = CLOCK_EVT_FEAT_PERIODIC;
821 ced->features |= CLOCK_EVT_FEAT_ONESHOT;
823 ced->cpumask = cpu_possible_mask;
824 ced->set_next_event = sh_cmt_clock_event_next;
825 ced->set_state_shutdown = sh_cmt_clock_event_shutdown;
826 ced->set_state_periodic = sh_cmt_clock_event_set_periodic;
827 ced->set_state_oneshot = sh_cmt_clock_event_set_oneshot;
828 ced->suspend = sh_cmt_clock_event_suspend;
829 ced->resume = sh_cmt_clock_event_resume;
831 /* TODO: calculate good shift from rate and counter bit width */
833 ced->mult = div_sc(ch->cmt->rate, NSEC_PER_SEC, ced->shift);
834 ced->max_delta_ns = clockevent_delta2ns(ch->max_match_value, ced);
835 ced->max_delta_ticks = ch->max_match_value;
836 ced->min_delta_ns = clockevent_delta2ns(0x1f, ced);
837 ced->min_delta_ticks = 0x1f;
839 dev_info(&ch->cmt->pdev->dev, "ch%u: used for clock events\n",
841 clockevents_register_device(ced);
846 static int sh_cmt_register(struct sh_cmt_channel *ch, const char *name,
847 bool clockevent, bool clocksource)
852 ch->cmt->has_clockevent = true;
853 ret = sh_cmt_register_clockevent(ch, name);
859 ch->cmt->has_clocksource = true;
860 sh_cmt_register_clocksource(ch, name);
866 static int sh_cmt_setup_channel(struct sh_cmt_channel *ch, unsigned int index,
867 unsigned int hwidx, bool clockevent,
868 bool clocksource, struct sh_cmt_device *cmt)
873 /* Skip unused channels. */
874 if (!clockevent && !clocksource)
880 ch->timer_bit = hwidx;
883 * Compute the address of the channel control register block. For the
884 * timers with a per-channel start/stop register, compute its address
887 switch (cmt->info->model) {
889 ch->ioctrl = cmt->mapbase + 2 + ch->hwidx * 6;
893 ch->ioctrl = cmt->mapbase + 0x10 + ch->hwidx * 0x10;
895 case SH_CMT0_RCAR_GEN2:
896 case SH_CMT1_RCAR_GEN2:
897 ch->iostart = cmt->mapbase + ch->hwidx * 0x100;
898 ch->ioctrl = ch->iostart + 0x10;
901 /* Enable the clock supply to the channel */
902 value = ioread32(cmt->mapbase + CMCLKE);
904 iowrite32(value, cmt->mapbase + CMCLKE);
908 if (cmt->info->width == (sizeof(ch->max_match_value) * 8))
909 ch->max_match_value = ~0;
911 ch->max_match_value = (1 << cmt->info->width) - 1;
913 ch->match_value = ch->max_match_value;
914 raw_spin_lock_init(&ch->lock);
916 ret = sh_cmt_register(ch, dev_name(&cmt->pdev->dev),
917 clockevent, clocksource);
919 dev_err(&cmt->pdev->dev, "ch%u: registration failed\n",
923 ch->cs_enabled = false;
928 static int sh_cmt_map_memory(struct sh_cmt_device *cmt)
930 struct resource *mem;
932 mem = platform_get_resource(cmt->pdev, IORESOURCE_MEM, 0);
934 dev_err(&cmt->pdev->dev, "failed to get I/O memory\n");
938 cmt->mapbase = ioremap(mem->start, resource_size(mem));
939 if (cmt->mapbase == NULL) {
940 dev_err(&cmt->pdev->dev, "failed to remap I/O memory\n");
947 static const struct platform_device_id sh_cmt_id_table[] = {
948 { "sh-cmt-16", (kernel_ulong_t)&sh_cmt_info[SH_CMT_16BIT] },
949 { "sh-cmt-32", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT] },
952 MODULE_DEVICE_TABLE(platform, sh_cmt_id_table);
954 static const struct of_device_id sh_cmt_of_table[] __maybe_unused = {
956 /* deprecated, preserved for backward compatibility */
957 .compatible = "renesas,cmt-48",
958 .data = &sh_cmt_info[SH_CMT_48BIT]
961 /* deprecated, preserved for backward compatibility */
962 .compatible = "renesas,cmt-48-gen2",
963 .data = &sh_cmt_info[SH_CMT0_RCAR_GEN2]
966 .compatible = "renesas,r8a7740-cmt1",
967 .data = &sh_cmt_info[SH_CMT_48BIT]
970 .compatible = "renesas,sh73a0-cmt1",
971 .data = &sh_cmt_info[SH_CMT_48BIT]
974 .compatible = "renesas,rcar-gen2-cmt0",
975 .data = &sh_cmt_info[SH_CMT0_RCAR_GEN2]
978 .compatible = "renesas,rcar-gen2-cmt1",
979 .data = &sh_cmt_info[SH_CMT1_RCAR_GEN2]
982 .compatible = "renesas,rcar-gen3-cmt0",
983 .data = &sh_cmt_info[SH_CMT0_RCAR_GEN2]
986 .compatible = "renesas,rcar-gen3-cmt1",
987 .data = &sh_cmt_info[SH_CMT1_RCAR_GEN2]
991 MODULE_DEVICE_TABLE(of, sh_cmt_of_table);
993 static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
995 unsigned int mask, i;
1000 raw_spin_lock_init(&cmt->lock);
1002 if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
1003 cmt->info = of_device_get_match_data(&pdev->dev);
1004 cmt->hw_channels = cmt->info->channels_mask;
1005 } else if (pdev->dev.platform_data) {
1006 struct sh_timer_config *cfg = pdev->dev.platform_data;
1007 const struct platform_device_id *id = pdev->id_entry;
1009 cmt->info = (const struct sh_cmt_info *)id->driver_data;
1010 cmt->hw_channels = cfg->channels_mask;
1012 dev_err(&cmt->pdev->dev, "missing platform data\n");
1016 /* Get hold of clock. */
1017 cmt->clk = clk_get(&cmt->pdev->dev, "fck");
1018 if (IS_ERR(cmt->clk)) {
1019 dev_err(&cmt->pdev->dev, "cannot get clock\n");
1020 return PTR_ERR(cmt->clk);
1023 ret = clk_prepare(cmt->clk);
1027 /* Determine clock rate. */
1028 ret = clk_enable(cmt->clk);
1030 goto err_clk_unprepare;
1032 rate = clk_get_rate(cmt->clk);
1035 goto err_clk_disable;
1038 /* We shall wait 2 input clks after register writes */
1039 if (cmt->info->model >= SH_CMT_48BIT)
1040 cmt->reg_delay = DIV_ROUND_UP(2UL * USEC_PER_SEC, rate);
1041 cmt->rate = rate / (cmt->info->width == 16 ? 512 : 8);
1043 /* Map the memory resource(s). */
1044 ret = sh_cmt_map_memory(cmt);
1046 goto err_clk_disable;
1048 /* Allocate and setup the channels. */
1049 cmt->num_channels = hweight8(cmt->hw_channels);
1050 cmt->channels = kcalloc(cmt->num_channels, sizeof(*cmt->channels),
1052 if (cmt->channels == NULL) {
1058 * Use the first channel as a clock event device and the second channel
1059 * as a clock source. If only one channel is available use it for both.
1061 for (i = 0, mask = cmt->hw_channels; i < cmt->num_channels; ++i) {
1062 unsigned int hwidx = ffs(mask) - 1;
1063 bool clocksource = i == 1 || cmt->num_channels == 1;
1064 bool clockevent = i == 0;
1066 ret = sh_cmt_setup_channel(&cmt->channels[i], i, hwidx,
1067 clockevent, clocksource, cmt);
1071 mask &= ~(1 << hwidx);
1074 clk_disable(cmt->clk);
1076 platform_set_drvdata(pdev, cmt);
1081 kfree(cmt->channels);
1082 iounmap(cmt->mapbase);
1084 clk_disable(cmt->clk);
1086 clk_unprepare(cmt->clk);
1092 static int sh_cmt_probe(struct platform_device *pdev)
1094 struct sh_cmt_device *cmt = platform_get_drvdata(pdev);
1097 if (!is_sh_early_platform_device(pdev)) {
1098 pm_runtime_set_active(&pdev->dev);
1099 pm_runtime_enable(&pdev->dev);
1103 dev_info(&pdev->dev, "kept as earlytimer\n");
1107 cmt = kzalloc(sizeof(*cmt), GFP_KERNEL);
1111 ret = sh_cmt_setup(cmt, pdev);
1114 pm_runtime_idle(&pdev->dev);
1117 if (is_sh_early_platform_device(pdev))
1121 if (cmt->has_clockevent || cmt->has_clocksource)
1122 pm_runtime_irq_safe(&pdev->dev);
1124 pm_runtime_idle(&pdev->dev);
1129 static int sh_cmt_remove(struct platform_device *pdev)
1131 return -EBUSY; /* cannot unregister clockevent and clocksource */
1134 static struct platform_driver sh_cmt_device_driver = {
1135 .probe = sh_cmt_probe,
1136 .remove = sh_cmt_remove,
1139 .of_match_table = of_match_ptr(sh_cmt_of_table),
1141 .id_table = sh_cmt_id_table,
1144 static int __init sh_cmt_init(void)
1146 return platform_driver_register(&sh_cmt_device_driver);
1149 static void __exit sh_cmt_exit(void)
1151 platform_driver_unregister(&sh_cmt_device_driver);
1154 #ifdef CONFIG_SUPERH
1155 sh_early_platform_init("earlytimer", &sh_cmt_device_driver);
1158 subsys_initcall(sh_cmt_init);
1159 module_exit(sh_cmt_exit);
1161 MODULE_AUTHOR("Magnus Damm");
1162 MODULE_DESCRIPTION("SuperH CMT Timer Driver");
1163 MODULE_LICENSE("GPL v2");