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Release 4.11 drivers/clocksource/sh_cmt.c

/*
 * 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 <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/sh_timer.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

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     48B-2
 * -----------------------------------------------------------------------------
 * 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 48-bit 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_32BIT_FAST,
	
SH_CMT_48BIT,
	
SH_CMT_48BIT_GEN2,
};


struct sh_cmt_info {
	
enum sh_cmt_model model;

	
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;
	
unsigned long rate;
	
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;

	
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)); }

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static unsigned long sh_cmt_read32(void __iomem *base, unsigned long offs) { return ioread32(base + (offs << 2)); }

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static void sh_cmt_write16(void __iomem *base, unsigned long offs, unsigned long value) { iowrite16(value, base + (offs << 1)); }

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static void sh_cmt_write32(void __iomem *base, unsigned long offs, unsigned long value) { iowrite32(value, base + (offs << 2)); }

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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_32BIT_FAST] = { .model = SH_CMT_32BIT_FAST, .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, .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_CMT_48BIT_GEN2] = { .model = SH_CMT_48BIT_GEN2, .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); }

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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); }

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static inline unsigned long sh_cmt_read_cmcsr(struct sh_cmt_channel *ch) { return ch->cmt->info->read_control(ch->ioctrl, CMCSR); }

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static inline void sh_cmt_write_cmcsr(struct sh_cmt_channel *ch, unsigned long value) { ch->cmt->info->write_control(ch->ioctrl, CMCSR, value); }

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static inline unsigned long sh_cmt_read_cmcnt(struct sh_cmt_channel *ch) { return ch->cmt->info->read_count(ch->ioctrl, CMCNT); }

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static inline void sh_cmt_write_cmcnt(struct sh_cmt_channel *ch, unsigned long value) { ch->cmt->info->write_count(ch->ioctrl, CMCNT, value); }

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static inline void sh_cmt_write_cmcor(struct sh_cmt_channel *ch, unsigned long value) { ch->cmt->info->write_count(ch->ioctrl, CMCOR, value); }

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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; }

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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); }

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static int sh_cmt_enable(struct sh_cmt_channel *ch, unsigned long *rate) { 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) { *rate = clk_get_rate(ch->cmt->clk) / 512; sh_cmt_write_cmcsr(ch, SH_CMT16_CMCSR_CMIE | SH_CMT16_CMCSR_CKS512); } else { *rate = clk_get_rate(ch->cmt->clk) / 8; 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; }

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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); }

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/* 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); }

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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); }

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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); }

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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; }

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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, &ch->rate); 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; }

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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); }

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static struct sh_cmt_channel *cs_to_sh_cmt(struct clocksource *cs) { return container_of(cs, struct sh_cmt_channel, cs); }

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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; }

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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) { __clocksource_update_freq_hz(cs, ch->rate); ch->cs_enabled = true; } return ret; }

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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; }

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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); }

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Laurent Pinchart612.50%133.33%
Total48100.00%3100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm1939.58%125.00%
Rafael J. Wysocki1531.25%125.00%
Geert Uytterhoeven816.67%125.00%
Laurent Pinchart612.50%125.00%
Total48100.00%4100.00%


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); /* Register with dummy 1 Hz value, gets updated in ->enable() */ clocksource_register_hz(cs, 1); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm9883.05%333.33%
Laurent Pinchart1311.02%444.44%
Paul Mundt65.08%111.11%
Rafael J. Wysocki10.85%111.11%
Total118100.00%9100.00%


static struct sh_cmt_channel *ced_to_sh_cmt(struct clock_event_device *ced) { return container_of(ced, struct sh_cmt_channel, ced); }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm2291.67%150.00%
Laurent Pinchart28.33%150.00%
Total24100.00%2100.00%


static void sh_cmt_clock_event_start(struct sh_cmt_channel *ch, int periodic) { struct clock_event_device *ced = &ch->ced; sh_cmt_start(ch, FLAG_CLOCKEVENT); /* TODO: calculate good shift from rate and counter bit width */ ced->shift = 32; ced->mult = div_sc(ch->rate, NSEC_PER_SEC, ced->shift); ced->max_delta_ns = clockevent_delta2ns(ch->max_match_value, ced); ced->min_delta_ns = clockevent_delta2ns(0x1f, ced); if (periodic) sh_cmt_set_next(ch, ((ch->rate + HZ/2) / HZ) - 1); else sh_cmt_set_next(ch, ch->max_match_value); }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm10491.23%266.67%
Laurent Pinchart108.77%133.33%
Total114100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm2374.19%133.33%
Viresh Kumar516.13%133.33%
Laurent Pinchart39.68%133.33%
Total31100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Viresh Kumar4760.26%120.00%
Magnus Damm1519.23%120.00%
Laurent Pinchart1012.82%240.00%
Paul Mundt67.69%120.00%
Total78100.00%5100.00%


static int sh_cmt_clock_event_set_oneshot(struct clock_event_device *ced) { return sh_cmt_clock_event_set_state(ced, 0); }

Contributors

PersonTokensPropCommitsCommitProp
Viresh Kumar1578.95%150.00%
Magnus Damm421.05%150.00%
Total19100.00%2100.00%


static int sh_cmt_clock_event_set_periodic(struct clock_event_device *ced) { return sh_cmt_clock_event_set_state(ced, 1); }

Contributors

PersonTokensPropCommitsCommitProp
Viresh Kumar1894.74%150.00%
Magnus Damm15.26%150.00%
Total19100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm5786.36%250.00%
Laurent Pinchart57.58%125.00%
Viresh Kumar46.06%125.00%
Total66100.00%4100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Rafael J. Wysocki2150.00%133.33%
Laurent Pinchart2150.00%266.67%
Total42100.00%3100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Laurent Pinchart2150.00%266.67%
Rafael J. Wysocki2150.00%133.33%
Total42100.00%3100.00%


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; dev_info(&ch->cmt->pdev->dev, "ch%u: used for clock events\n", ch->index); clockevents_register_device(ced); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Laurent Pinchart12655.75%660.00%
Magnus Damm6830.09%110.00%
Viresh Kumar146.19%110.00%
Rafael J. Wysocki125.31%110.00%
Paul Mundt62.65%110.00%
Total226100.00%10100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Laurent Pinchart4555.56%666.67%
Magnus Damm3543.21%222.22%
Paul Mundt11.23%111.11%
Total81100.00%9100.00%


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; /* * 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_CMT_32BIT_FAST: /* * The 32-bit "fast" timer has a single channel at hwidx 5 but * is located at offset 0x40 instead of 0x60 for some reason. */ ch->ioctrl = cmt->mapbase + 0x40; break; case SH_CMT_48BIT_GEN2: ch->iostart = cmt->mapbase + ch->hwidx * 0x100; ch->ioctrl = ch->iostart + 0x10; 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); ch->timer_bit = cmt->info->model == SH_CMT_48BIT_GEN2 ? 0 : ch->hwidx; 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; }

Contributors

PersonTokensPropCommitsCommitProp
Laurent Pinchart292100.00%6100.00%
Total292100.00%6100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm5253.61%133.33%
Laurent Pinchart4546.39%266.67%
Total97100.00%3100.00%

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-32", .data = &sh_cmt_info[SH_CMT_32BIT] }, { .compatible = "renesas,cmt-32-fast", .data = &sh_cmt_info[SH_CMT_32BIT_FAST] }, { .compatible = "renesas,cmt-48", .data = &sh_cmt_info[SH_CMT_48BIT] }, { .compatible = "renesas,cmt-48-gen2", .data = &sh_cmt_info[SH_CMT_48BIT_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); }

Contributors

PersonTokensPropCommitsCommitProp
Laurent Pinchart37100.00%2100.00%
Total37100.00%2100.00%


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; 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; /* 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; }

Contributors

PersonTokensPropCommitsCommitProp
Laurent Pinchart37282.85%952.94%
Magnus Damm5011.14%529.41%
Paul Mundt276.01%317.65%
Total449100.00%17100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Rafael J. Wysocki7646.06%333.33%
Magnus Damm7042.42%222.22%
Laurent Pinchart137.88%333.33%
Paul Mundt63.64%111.11%
Total165100.00%9100.00%


static int sh_cmt_remove(struct platform_device *pdev) { return -EBUSY; /* cannot unregister clockevent and clocksource */ }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm16100.00%1100.00%
Total16100.00%1100.00%

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); }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm16100.00%1100.00%
Total16100.00%1100.00%


static void __exit sh_cmt_exit(void) { platform_driver_unregister(&sh_cmt_device_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm15100.00%1100.00%
Total15100.00%1100.00%

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");

Overall Contributors

PersonTokensPropCommitsCommitProp
Magnus Damm225346.23%1729.82%
Laurent Pinchart211043.30%2340.35%
Rafael J. Wysocki2585.29%35.26%
Viresh Kumar1112.28%11.75%
Paul Mundt851.74%610.53%
Takashi Yoshii330.68%11.75%
Geert Uytterhoeven160.33%11.75%
Paul Gortmaker20.04%11.75%
Tejun Heo20.04%11.75%
John Stultz10.02%11.75%
Simon Horman10.02%11.75%
Thomas Gleixner10.02%11.75%
Total4873100.00%57100.00%
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