/* * SuperH Timer Support - CMT * * Copyright (C) 2008 Magnus Damm * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct sh_cmt_device; /* * The CMT comes in 5 different identified flavours, depending not only on the * SoC but also on the particular instance. The following table lists the main * characteristics of those flavours. * * 16B 32B 32B-F 48B R-Car Gen2 * ----------------------------------------------------------------------------- * Channels 2 1/4 1 6 2/8 * Control Width 16 16 16 16 32 * Counter Width 16 32 32 32/48 32/48 * Shared Start/Stop Y Y Y Y N * * The r8a73a4 / R-Car Gen2 version has a per-channel start/stop register * located in the channel registers block. All other versions have a shared * start/stop register located in the global space. * * Channels are indexed from 0 to N-1 in the documentation. The channel index * infers the start/stop bit position in the control register and the channel * registers block address. Some CMT instances have a subset of channels * available, in which case the index in the documentation doesn't match the * "real" index as implemented in hardware. This is for instance the case with * CMT0 on r8a7740, which is a 32-bit variant with a single channel numbered 0 * in the documentation but using start/stop bit 5 and having its registers * block at 0x60. * * Similarly CMT0 on r8a73a4, r8a7790 and r8a7791, while implementing 32-bit * channels only, is a 48-bit gen2 CMT with the 48-bit channels unavailable. */ enum sh_cmt_model { SH_CMT_16BIT, SH_CMT_32BIT, SH_CMT_48BIT, SH_CMT0_RCAR_GEN2, SH_CMT1_RCAR_GEN2, }; struct sh_cmt_info { enum sh_cmt_model model; unsigned int channels_mask; unsigned long width; /* 16 or 32 bit version of hardware block */ unsigned long overflow_bit; unsigned long clear_bits; /* callbacks for CMSTR and CMCSR access */ unsigned long (*read_control)(void __iomem *base, unsigned long offs); void (*write_control)(void __iomem *base, unsigned long offs, unsigned long value); /* callbacks for CMCNT and CMCOR access */ unsigned long (*read_count)(void __iomem *base, unsigned long offs); void (*write_count)(void __iomem *base, unsigned long offs, unsigned long value); }; struct sh_cmt_channel { struct sh_cmt_device *cmt; unsigned int index; /* Index in the documentation */ unsigned int hwidx; /* Real hardware index */ void __iomem *iostart; void __iomem *ioctrl; unsigned int timer_bit; unsigned long flags; unsigned long match_value; unsigned long next_match_value; unsigned long max_match_value; raw_spinlock_t lock; struct clock_event_device ced; struct clocksource cs; unsigned long total_cycles; bool cs_enabled; }; struct sh_cmt_device { struct platform_device *pdev; const struct sh_cmt_info *info; void __iomem *mapbase; struct clk *clk; unsigned long rate; raw_spinlock_t lock; /* Protect the shared start/stop register */ struct sh_cmt_channel *channels; unsigned int num_channels; unsigned int hw_channels; bool has_clockevent; bool has_clocksource; }; #define SH_CMT16_CMCSR_CMF (1 << 7) #define SH_CMT16_CMCSR_CMIE (1 << 6) #define SH_CMT16_CMCSR_CKS8 (0 << 0) #define SH_CMT16_CMCSR_CKS32 (1 << 0) #define SH_CMT16_CMCSR_CKS128 (2 << 0) #define SH_CMT16_CMCSR_CKS512 (3 << 0) #define SH_CMT16_CMCSR_CKS_MASK (3 << 0) #define SH_CMT32_CMCSR_CMF (1 << 15) #define SH_CMT32_CMCSR_OVF (1 << 14) #define SH_CMT32_CMCSR_WRFLG (1 << 13) #define SH_CMT32_CMCSR_STTF (1 << 12) #define SH_CMT32_CMCSR_STPF (1 << 11) #define SH_CMT32_CMCSR_SSIE (1 << 10) #define SH_CMT32_CMCSR_CMS (1 << 9) #define SH_CMT32_CMCSR_CMM (1 << 8) #define SH_CMT32_CMCSR_CMTOUT_IE (1 << 7) #define SH_CMT32_CMCSR_CMR_NONE (0 << 4) #define SH_CMT32_CMCSR_CMR_DMA (1 << 4) #define SH_CMT32_CMCSR_CMR_IRQ (2 << 4) #define SH_CMT32_CMCSR_CMR_MASK (3 << 4) #define SH_CMT32_CMCSR_DBGIVD (1 << 3) #define SH_CMT32_CMCSR_CKS_RCLK8 (4 << 0) #define SH_CMT32_CMCSR_CKS_RCLK32 (5 << 0) #define SH_CMT32_CMCSR_CKS_RCLK128 (6 << 0) #define SH_CMT32_CMCSR_CKS_RCLK1 (7 << 0) #define SH_CMT32_CMCSR_CKS_MASK (7 << 0) static unsigned long sh_cmt_read16(void __iomem *base, unsigned long offs) { return ioread16(base + (offs << 1)); } static unsigned long sh_cmt_read32(void __iomem *base, unsigned long offs) { return ioread32(base + (offs << 2)); } static void sh_cmt_write16(void __iomem *base, unsigned long offs, unsigned long value) { iowrite16(value, base + (offs << 1)); } static void sh_cmt_write32(void __iomem *base, unsigned long offs, unsigned long value) { iowrite32(value, base + (offs << 2)); } static const struct sh_cmt_info sh_cmt_info[] = { [SH_CMT_16BIT] = { .model = SH_CMT_16BIT, .width = 16, .overflow_bit = SH_CMT16_CMCSR_CMF, .clear_bits = ~SH_CMT16_CMCSR_CMF, .read_control = sh_cmt_read16, .write_control = sh_cmt_write16, .read_count = sh_cmt_read16, .write_count = sh_cmt_write16, }, [SH_CMT_32BIT] = { .model = SH_CMT_32BIT, .width = 32, .overflow_bit = SH_CMT32_CMCSR_CMF, .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF), .read_control = sh_cmt_read16, .write_control = sh_cmt_write16, .read_count = sh_cmt_read32, .write_count = sh_cmt_write32, }, [SH_CMT_48BIT] = { .model = SH_CMT_48BIT, .channels_mask = 0x3f, .width = 32, .overflow_bit = SH_CMT32_CMCSR_CMF, .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF), .read_control = sh_cmt_read32, .write_control = sh_cmt_write32, .read_count = sh_cmt_read32, .write_count = sh_cmt_write32, }, [SH_CMT0_RCAR_GEN2] = { .model = SH_CMT0_RCAR_GEN2, .channels_mask = 0x60, .width = 32, .overflow_bit = SH_CMT32_CMCSR_CMF, .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF), .read_control = sh_cmt_read32, .write_control = sh_cmt_write32, .read_count = sh_cmt_read32, .write_count = sh_cmt_write32, }, [SH_CMT1_RCAR_GEN2] = { .model = SH_CMT1_RCAR_GEN2, .channels_mask = 0xff, .width = 32, .overflow_bit = SH_CMT32_CMCSR_CMF, .clear_bits = ~(SH_CMT32_CMCSR_CMF | SH_CMT32_CMCSR_OVF), .read_control = sh_cmt_read32, .write_control = sh_cmt_write32, .read_count = sh_cmt_read32, .write_count = sh_cmt_write32, }, }; #define CMCSR 0 /* channel register */ #define CMCNT 1 /* channel register */ #define CMCOR 2 /* channel register */ static inline unsigned long sh_cmt_read_cmstr(struct sh_cmt_channel *ch) { if (ch->iostart) return ch->cmt->info->read_control(ch->iostart, 0); else return ch->cmt->info->read_control(ch->cmt->mapbase, 0); } static inline void sh_cmt_write_cmstr(struct sh_cmt_channel *ch, unsigned long value) { if (ch->iostart) ch->cmt->info->write_control(ch->iostart, 0, value); else ch->cmt->info->write_control(ch->cmt->mapbase, 0, value); } static inline unsigned long sh_cmt_read_cmcsr(struct sh_cmt_channel *ch) { return ch->cmt->info->read_control(ch->ioctrl, CMCSR); } static inline void sh_cmt_write_cmcsr(struct sh_cmt_channel *ch, unsigned long value) { ch->cmt->info->write_control(ch->ioctrl, CMCSR, value); } static inline unsigned long sh_cmt_read_cmcnt(struct sh_cmt_channel *ch) { return ch->cmt->info->read_count(ch->ioctrl, CMCNT); } static inline void sh_cmt_write_cmcnt(struct sh_cmt_channel *ch, unsigned long value) { ch->cmt->info->write_count(ch->ioctrl, CMCNT, value); } static inline void sh_cmt_write_cmcor(struct sh_cmt_channel *ch, unsigned long value) { ch->cmt->info->write_count(ch->ioctrl, CMCOR, value); } static unsigned long sh_cmt_get_counter(struct sh_cmt_channel *ch, int *has_wrapped) { unsigned long v1, v2, v3; int o1, o2; o1 = sh_cmt_read_cmcsr(ch) & ch->cmt->info->overflow_bit; /* Make sure the timer value is stable. Stolen from acpi_pm.c */ do { o2 = o1; v1 = sh_cmt_read_cmcnt(ch); v2 = sh_cmt_read_cmcnt(ch); v3 = sh_cmt_read_cmcnt(ch); o1 = sh_cmt_read_cmcsr(ch) & ch->cmt->info->overflow_bit; } while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2))); *has_wrapped = o1; return v2; } static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start) { unsigned long flags, value; /* start stop register shared by multiple timer channels */ raw_spin_lock_irqsave(&ch->cmt->lock, flags); value = sh_cmt_read_cmstr(ch); if (start) value |= 1 << ch->timer_bit; else value &= ~(1 << ch->timer_bit); sh_cmt_write_cmstr(ch, value); raw_spin_unlock_irqrestore(&ch->cmt->lock, flags); } static int sh_cmt_enable(struct sh_cmt_channel *ch) { int k, ret; pm_runtime_get_sync(&ch->cmt->pdev->dev); dev_pm_syscore_device(&ch->cmt->pdev->dev, true); /* enable clock */ ret = clk_enable(ch->cmt->clk); if (ret) { dev_err(&ch->cmt->pdev->dev, "ch%u: cannot enable clock\n", ch->index); goto err0; } /* make sure channel is disabled */ sh_cmt_start_stop_ch(ch, 0); /* configure channel, periodic mode and maximum timeout */ if (ch->cmt->info->width == 16) { sh_cmt_write_cmcsr(ch, SH_CMT16_CMCSR_CMIE | SH_CMT16_CMCSR_CKS512); } else { sh_cmt_write_cmcsr(ch, SH_CMT32_CMCSR_CMM | SH_CMT32_CMCSR_CMTOUT_IE | SH_CMT32_CMCSR_CMR_IRQ | SH_CMT32_CMCSR_CKS_RCLK8); } sh_cmt_write_cmcor(ch, 0xffffffff); sh_cmt_write_cmcnt(ch, 0); /* * According to the sh73a0 user's manual, as CMCNT can be operated * only by the RCLK (Pseudo 32 KHz), there's one restriction on * modifying CMCNT register; two RCLK cycles are necessary before * this register is either read or any modification of the value * it holds is reflected in the LSI's actual operation. * * While at it, we're supposed to clear out the CMCNT as of this * moment, so make sure it's processed properly here. This will * take RCLKx2 at maximum. */ for (k = 0; k < 100; k++) { if (!sh_cmt_read_cmcnt(ch)) break; udelay(1); } if (sh_cmt_read_cmcnt(ch)) { dev_err(&ch->cmt->pdev->dev, "ch%u: cannot clear CMCNT\n", ch->index); ret = -ETIMEDOUT; goto err1; } /* enable channel */ sh_cmt_start_stop_ch(ch, 1); return 0; err1: /* stop clock */ clk_disable(ch->cmt->clk); err0: return ret; } static void sh_cmt_disable(struct sh_cmt_channel *ch) { /* disable channel */ sh_cmt_start_stop_ch(ch, 0); /* disable interrupts in CMT block */ sh_cmt_write_cmcsr(ch, 0); /* stop clock */ clk_disable(ch->cmt->clk); dev_pm_syscore_device(&ch->cmt->pdev->dev, false); pm_runtime_put(&ch->cmt->pdev->dev); } /* private flags */ #define FLAG_CLOCKEVENT (1 << 0) #define FLAG_CLOCKSOURCE (1 << 1) #define FLAG_REPROGRAM (1 << 2) #define FLAG_SKIPEVENT (1 << 3) #define FLAG_IRQCONTEXT (1 << 4) static void sh_cmt_clock_event_program_verify(struct sh_cmt_channel *ch, int absolute) { unsigned long new_match; unsigned long value = ch->next_match_value; unsigned long delay = 0; unsigned long now = 0; int has_wrapped; now = sh_cmt_get_counter(ch, &has_wrapped); ch->flags |= FLAG_REPROGRAM; /* force reprogram */ if (has_wrapped) { /* we're competing with the interrupt handler. * -> let the interrupt handler reprogram the timer. * -> interrupt number two handles the event. */ ch->flags |= FLAG_SKIPEVENT; return; } if (absolute) now = 0; do { /* reprogram the timer hardware, * but don't save the new match value yet. */ new_match = now + value + delay; if (new_match > ch->max_match_value) new_match = ch->max_match_value; sh_cmt_write_cmcor(ch, new_match); now = sh_cmt_get_counter(ch, &has_wrapped); if (has_wrapped && (new_match > ch->match_value)) { /* we are changing to a greater match value, * so this wrap must be caused by the counter * matching the old value. * -> first interrupt reprograms the timer. * -> interrupt number two handles the event. */ ch->flags |= FLAG_SKIPEVENT; break; } if (has_wrapped) { /* we are changing to a smaller match value, * so the wrap must be caused by the counter * matching the new value. * -> save programmed match value. * -> let isr handle the event. */ ch->match_value = new_match; break; } /* be safe: verify hardware settings */ if (now < new_match) { /* timer value is below match value, all good. * this makes sure we won't miss any match events. * -> save programmed match value. * -> let isr handle the event. */ ch->match_value = new_match; break; } /* the counter has reached a value greater * than our new match value. and since the * has_wrapped flag isn't set we must have * programmed a too close event. * -> increase delay and retry. */ if (delay) delay <<= 1; else delay = 1; if (!delay) dev_warn(&ch->cmt->pdev->dev, "ch%u: too long delay\n", ch->index); } while (delay); } static void __sh_cmt_set_next(struct sh_cmt_channel *ch, unsigned long delta) { if (delta > ch->max_match_value) dev_warn(&ch->cmt->pdev->dev, "ch%u: delta out of range\n", ch->index); ch->next_match_value = delta; sh_cmt_clock_event_program_verify(ch, 0); } static void sh_cmt_set_next(struct sh_cmt_channel *ch, unsigned long delta) { unsigned long flags; raw_spin_lock_irqsave(&ch->lock, flags); __sh_cmt_set_next(ch, delta); raw_spin_unlock_irqrestore(&ch->lock, flags); } static irqreturn_t sh_cmt_interrupt(int irq, void *dev_id) { struct sh_cmt_channel *ch = dev_id; /* clear flags */ sh_cmt_write_cmcsr(ch, sh_cmt_read_cmcsr(ch) & ch->cmt->info->clear_bits); /* update clock source counter to begin with if enabled * the wrap flag should be cleared by the timer specific * isr before we end up here. */ if (ch->flags & FLAG_CLOCKSOURCE) ch->total_cycles += ch->match_value + 1; if (!(ch->flags & FLAG_REPROGRAM)) ch->next_match_value = ch->max_match_value; ch->flags |= FLAG_IRQCONTEXT; if (ch->flags & FLAG_CLOCKEVENT) { if (!(ch->flags & FLAG_SKIPEVENT)) { if (clockevent_state_oneshot(&ch->ced)) { ch->next_match_value = ch->max_match_value; ch->flags |= FLAG_REPROGRAM; } ch->ced.event_handler(&ch->ced); } } ch->flags &= ~FLAG_SKIPEVENT; if (ch->flags & FLAG_REPROGRAM) { ch->flags &= ~FLAG_REPROGRAM; sh_cmt_clock_event_program_verify(ch, 1); if (ch->flags & FLAG_CLOCKEVENT) if ((clockevent_state_shutdown(&ch->ced)) || (ch->match_value == ch->next_match_value)) ch->flags &= ~FLAG_REPROGRAM; } ch->flags &= ~FLAG_IRQCONTEXT; return IRQ_HANDLED; } static int sh_cmt_start(struct sh_cmt_channel *ch, unsigned long flag) { int ret = 0; unsigned long flags; raw_spin_lock_irqsave(&ch->lock, flags); if (!(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE))) ret = sh_cmt_enable(ch); if (ret) goto out; ch->flags |= flag; /* setup timeout if no clockevent */ if ((flag == FLAG_CLOCKSOURCE) && (!(ch->flags & FLAG_CLOCKEVENT))) __sh_cmt_set_next(ch, ch->max_match_value); out: raw_spin_unlock_irqrestore(&ch->lock, flags); return ret; } static void sh_cmt_stop(struct sh_cmt_channel *ch, unsigned long flag) { unsigned long flags; unsigned long f; raw_spin_lock_irqsave(&ch->lock, flags); f = ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE); ch->flags &= ~flag; if (f && !(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE))) sh_cmt_disable(ch); /* adjust the timeout to maximum if only clocksource left */ if ((flag == FLAG_CLOCKEVENT) && (ch->flags & FLAG_CLOCKSOURCE)) __sh_cmt_set_next(ch, ch->max_match_value); raw_spin_unlock_irqrestore(&ch->lock, flags); } static struct sh_cmt_channel *cs_to_sh_cmt(struct clocksource *cs) { return container_of(cs, struct sh_cmt_channel, cs); } static u64 sh_cmt_clocksource_read(struct clocksource *cs) { struct sh_cmt_channel *ch = cs_to_sh_cmt(cs); unsigned long flags, raw; unsigned long value; int has_wrapped; raw_spin_lock_irqsave(&ch->lock, flags); value = ch->total_cycles; raw = sh_cmt_get_counter(ch, &has_wrapped); if (unlikely(has_wrapped)) raw += ch->match_value + 1; raw_spin_unlock_irqrestore(&ch->lock, flags); return value + raw; } static int sh_cmt_clocksource_enable(struct clocksource *cs) { int ret; struct sh_cmt_channel *ch = cs_to_sh_cmt(cs); WARN_ON(ch->cs_enabled); ch->total_cycles = 0; ret = sh_cmt_start(ch, FLAG_CLOCKSOURCE); if (!ret) ch->cs_enabled = true; return ret; } static void sh_cmt_clocksource_disable(struct clocksource *cs) { struct sh_cmt_channel *ch = cs_to_sh_cmt(cs); WARN_ON(!ch->cs_enabled); sh_cmt_stop(ch, FLAG_CLOCKSOURCE); ch->cs_enabled = false; } static void sh_cmt_clocksource_suspend(struct clocksource *cs) { struct sh_cmt_channel *ch = cs_to_sh_cmt(cs); if (!ch->cs_enabled) return; sh_cmt_stop(ch, FLAG_CLOCKSOURCE); pm_genpd_syscore_poweroff(&ch->cmt->pdev->dev); } static void sh_cmt_clocksource_resume(struct clocksource *cs) { struct sh_cmt_channel *ch = cs_to_sh_cmt(cs); if (!ch->cs_enabled) return; pm_genpd_syscore_poweron(&ch->cmt->pdev->dev); sh_cmt_start(ch, FLAG_CLOCKSOURCE); } static int sh_cmt_register_clocksource(struct sh_cmt_channel *ch, const char *name) { struct clocksource *cs = &ch->cs; cs->name = name; cs->rating = 125; cs->read = sh_cmt_clocksource_read; cs->enable = sh_cmt_clocksource_enable; cs->disable = sh_cmt_clocksource_disable; cs->suspend = sh_cmt_clocksource_suspend; cs->resume = sh_cmt_clocksource_resume; cs->mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8); cs->flags = CLOCK_SOURCE_IS_CONTINUOUS; dev_info(&ch->cmt->pdev->dev, "ch%u: used as clock source\n", ch->index); clocksource_register_hz(cs, ch->cmt->rate); return 0; } static struct sh_cmt_channel *ced_to_sh_cmt(struct clock_event_device *ced) { return container_of(ced, struct sh_cmt_channel, ced); } static void sh_cmt_clock_event_start(struct sh_cmt_channel *ch, int periodic) { sh_cmt_start(ch, FLAG_CLOCKEVENT); if (periodic) sh_cmt_set_next(ch, ((ch->cmt->rate + HZ/2) / HZ) - 1); else sh_cmt_set_next(ch, ch->max_match_value); } static int sh_cmt_clock_event_shutdown(struct clock_event_device *ced) { struct sh_cmt_channel *ch = ced_to_sh_cmt(ced); sh_cmt_stop(ch, FLAG_CLOCKEVENT); return 0; } static int sh_cmt_clock_event_set_state(struct clock_event_device *ced, int periodic) { struct sh_cmt_channel *ch = ced_to_sh_cmt(ced); /* deal with old setting first */ if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced)) sh_cmt_stop(ch, FLAG_CLOCKEVENT); dev_info(&ch->cmt->pdev->dev, "ch%u: used for %s clock events\n", ch->index, periodic ? "periodic" : "oneshot"); sh_cmt_clock_event_start(ch, periodic); return 0; } static int sh_cmt_clock_event_set_oneshot(struct clock_event_device *ced) { return sh_cmt_clock_event_set_state(ced, 0); } static int sh_cmt_clock_event_set_periodic(struct clock_event_device *ced) { return sh_cmt_clock_event_set_state(ced, 1); } static int sh_cmt_clock_event_next(unsigned long delta, struct clock_event_device *ced) { struct sh_cmt_channel *ch = ced_to_sh_cmt(ced); BUG_ON(!clockevent_state_oneshot(ced)); if (likely(ch->flags & FLAG_IRQCONTEXT)) ch->next_match_value = delta - 1; else sh_cmt_set_next(ch, delta - 1); return 0; } static void sh_cmt_clock_event_suspend(struct clock_event_device *ced) { struct sh_cmt_channel *ch = ced_to_sh_cmt(ced); pm_genpd_syscore_poweroff(&ch->cmt->pdev->dev); clk_unprepare(ch->cmt->clk); } static void sh_cmt_clock_event_resume(struct clock_event_device *ced) { struct sh_cmt_channel *ch = ced_to_sh_cmt(ced); clk_prepare(ch->cmt->clk); pm_genpd_syscore_poweron(&ch->cmt->pdev->dev); } static int sh_cmt_register_clockevent(struct sh_cmt_channel *ch, const char *name) { struct clock_event_device *ced = &ch->ced; int irq; int ret; irq = platform_get_irq(ch->cmt->pdev, ch->index); if (irq < 0) { dev_err(&ch->cmt->pdev->dev, "ch%u: failed to get irq\n", ch->index); return irq; } ret = request_irq(irq, sh_cmt_interrupt, IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING, dev_name(&ch->cmt->pdev->dev), ch); if (ret) { dev_err(&ch->cmt->pdev->dev, "ch%u: failed to request irq %d\n", ch->index, irq); return ret; } ced->name = name; ced->features = CLOCK_EVT_FEAT_PERIODIC; ced->features |= CLOCK_EVT_FEAT_ONESHOT; ced->rating = 125; ced->cpumask = cpu_possible_mask; ced->set_next_event = sh_cmt_clock_event_next; ced->set_state_shutdown = sh_cmt_clock_event_shutdown; ced->set_state_periodic = sh_cmt_clock_event_set_periodic; ced->set_state_oneshot = sh_cmt_clock_event_set_oneshot; ced->suspend = sh_cmt_clock_event_suspend; ced->resume = sh_cmt_clock_event_resume; /* TODO: calculate good shift from rate and counter bit width */ ced->shift = 32; ced->mult = div_sc(ch->cmt->rate, NSEC_PER_SEC, ced->shift); ced->max_delta_ns = clockevent_delta2ns(ch->max_match_value, ced); ced->max_delta_ticks = ch->max_match_value; ced->min_delta_ns = clockevent_delta2ns(0x1f, ced); ced->min_delta_ticks = 0x1f; dev_info(&ch->cmt->pdev->dev, "ch%u: used for clock events\n", ch->index); clockevents_register_device(ced); return 0; } static int sh_cmt_register(struct sh_cmt_channel *ch, const char *name, bool clockevent, bool clocksource) { int ret; if (clockevent) { ch->cmt->has_clockevent = true; ret = sh_cmt_register_clockevent(ch, name); if (ret < 0) return ret; } if (clocksource) { ch->cmt->has_clocksource = true; sh_cmt_register_clocksource(ch, name); } return 0; } static int sh_cmt_setup_channel(struct sh_cmt_channel *ch, unsigned int index, unsigned int hwidx, bool clockevent, bool clocksource, struct sh_cmt_device *cmt) { int ret; /* Skip unused channels. */ if (!clockevent && !clocksource) return 0; ch->cmt = cmt; ch->index = index; ch->hwidx = hwidx; ch->timer_bit = hwidx; /* * Compute the address of the channel control register block. For the * timers with a per-channel start/stop register, compute its address * as well. */ switch (cmt->info->model) { case SH_CMT_16BIT: ch->ioctrl = cmt->mapbase + 2 + ch->hwidx * 6; break; case SH_CMT_32BIT: case SH_CMT_48BIT: ch->ioctrl = cmt->mapbase + 0x10 + ch->hwidx * 0x10; break; case SH_CMT0_RCAR_GEN2: case SH_CMT1_RCAR_GEN2: ch->iostart = cmt->mapbase + ch->hwidx * 0x100; ch->ioctrl = ch->iostart + 0x10; ch->timer_bit = 0; break; } if (cmt->info->width == (sizeof(ch->max_match_value) * 8)) ch->max_match_value = ~0; else ch->max_match_value = (1 << cmt->info->width) - 1; ch->match_value = ch->max_match_value; raw_spin_lock_init(&ch->lock); ret = sh_cmt_register(ch, dev_name(&cmt->pdev->dev), clockevent, clocksource); if (ret) { dev_err(&cmt->pdev->dev, "ch%u: registration failed\n", ch->index); return ret; } ch->cs_enabled = false; return 0; } static int sh_cmt_map_memory(struct sh_cmt_device *cmt) { struct resource *mem; mem = platform_get_resource(cmt->pdev, IORESOURCE_MEM, 0); if (!mem) { dev_err(&cmt->pdev->dev, "failed to get I/O memory\n"); return -ENXIO; } cmt->mapbase = ioremap_nocache(mem->start, resource_size(mem)); if (cmt->mapbase == NULL) { dev_err(&cmt->pdev->dev, "failed to remap I/O memory\n"); return -ENXIO; } return 0; } static const struct platform_device_id sh_cmt_id_table[] = { { "sh-cmt-16", (kernel_ulong_t)&sh_cmt_info[SH_CMT_16BIT] }, { "sh-cmt-32", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT] }, { } }; MODULE_DEVICE_TABLE(platform, sh_cmt_id_table); static const struct of_device_id sh_cmt_of_table[] __maybe_unused = { { .compatible = "renesas,cmt-48", .data = &sh_cmt_info[SH_CMT_48BIT] }, { .compatible = "renesas,cmt-48-gen2", .data = &sh_cmt_info[SH_CMT0_RCAR_GEN2] }, { .compatible = "renesas,rcar-gen2-cmt0", .data = &sh_cmt_info[SH_CMT0_RCAR_GEN2] }, { .compatible = "renesas,rcar-gen2-cmt1", .data = &sh_cmt_info[SH_CMT1_RCAR_GEN2] }, { } }; MODULE_DEVICE_TABLE(of, sh_cmt_of_table); static int sh_cmt_parse_dt(struct sh_cmt_device *cmt) { struct device_node *np = cmt->pdev->dev.of_node; return of_property_read_u32(np, "renesas,channels-mask", &cmt->hw_channels); } static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev) { unsigned int mask; unsigned int i; int ret; cmt->pdev = pdev; raw_spin_lock_init(&cmt->lock); if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) { const struct of_device_id *id; id = of_match_node(sh_cmt_of_table, pdev->dev.of_node); cmt->info = id->data; /* prefer in-driver channel configuration over DT */ if (cmt->info->channels_mask) { cmt->hw_channels = cmt->info->channels_mask; } else { ret = sh_cmt_parse_dt(cmt); if (ret < 0) return ret; } } else if (pdev->dev.platform_data) { struct sh_timer_config *cfg = pdev->dev.platform_data; const struct platform_device_id *id = pdev->id_entry; cmt->info = (const struct sh_cmt_info *)id->driver_data; cmt->hw_channels = cfg->channels_mask; } else { dev_err(&cmt->pdev->dev, "missing platform data\n"); return -ENXIO; } /* Get hold of clock. */ cmt->clk = clk_get(&cmt->pdev->dev, "fck"); if (IS_ERR(cmt->clk)) { dev_err(&cmt->pdev->dev, "cannot get clock\n"); return PTR_ERR(cmt->clk); } ret = clk_prepare(cmt->clk); if (ret < 0) goto err_clk_put; /* Determine clock rate. */ ret = clk_enable(cmt->clk); if (ret < 0) goto err_clk_unprepare; if (cmt->info->width == 16) cmt->rate = clk_get_rate(cmt->clk) / 512; else cmt->rate = clk_get_rate(cmt->clk) / 8; clk_disable(cmt->clk); /* Map the memory resource(s). */ ret = sh_cmt_map_memory(cmt); if (ret < 0) goto err_clk_unprepare; /* Allocate and setup the channels. */ cmt->num_channels = hweight8(cmt->hw_channels); cmt->channels = kzalloc(cmt->num_channels * sizeof(*cmt->channels), GFP_KERNEL); if (cmt->channels == NULL) { ret = -ENOMEM; goto err_unmap; } /* * Use the first channel as a clock event device and the second channel * as a clock source. If only one channel is available use it for both. */ for (i = 0, mask = cmt->hw_channels; i < cmt->num_channels; ++i) { unsigned int hwidx = ffs(mask) - 1; bool clocksource = i == 1 || cmt->num_channels == 1; bool clockevent = i == 0; ret = sh_cmt_setup_channel(&cmt->channels[i], i, hwidx, clockevent, clocksource, cmt); if (ret < 0) goto err_unmap; mask &= ~(1 << hwidx); } platform_set_drvdata(pdev, cmt); return 0; err_unmap: kfree(cmt->channels); iounmap(cmt->mapbase); err_clk_unprepare: clk_unprepare(cmt->clk); err_clk_put: clk_put(cmt->clk); return ret; } static int sh_cmt_probe(struct platform_device *pdev) { struct sh_cmt_device *cmt = platform_get_drvdata(pdev); int ret; if (!is_early_platform_device(pdev)) { pm_runtime_set_active(&pdev->dev); pm_runtime_enable(&pdev->dev); } if (cmt) { dev_info(&pdev->dev, "kept as earlytimer\n"); goto out; } cmt = kzalloc(sizeof(*cmt), GFP_KERNEL); if (cmt == NULL) return -ENOMEM; ret = sh_cmt_setup(cmt, pdev); if (ret) { kfree(cmt); pm_runtime_idle(&pdev->dev); return ret; } if (is_early_platform_device(pdev)) return 0; out: if (cmt->has_clockevent || cmt->has_clocksource) pm_runtime_irq_safe(&pdev->dev); else pm_runtime_idle(&pdev->dev); return 0; } static int sh_cmt_remove(struct platform_device *pdev) { return -EBUSY; /* cannot unregister clockevent and clocksource */ } static struct platform_driver sh_cmt_device_driver = { .probe = sh_cmt_probe, .remove = sh_cmt_remove, .driver = { .name = "sh_cmt", .of_match_table = of_match_ptr(sh_cmt_of_table), }, .id_table = sh_cmt_id_table, }; static int __init sh_cmt_init(void) { return platform_driver_register(&sh_cmt_device_driver); } static void __exit sh_cmt_exit(void) { platform_driver_unregister(&sh_cmt_device_driver); } early_platform_init("earlytimer", &sh_cmt_device_driver); subsys_initcall(sh_cmt_init); module_exit(sh_cmt_exit); MODULE_AUTHOR("Magnus Damm"); MODULE_DESCRIPTION("SuperH CMT Timer Driver"); MODULE_LICENSE("GPL v2");