diff options
Diffstat (limited to 'drivers/clocksource/dw_apb_timer.c')
| -rw-r--r-- | drivers/clocksource/dw_apb_timer.c | 247 |
1 files changed, 118 insertions, 129 deletions
diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c index e54ca1062d8e..3a55ae5fe225 100644 --- a/drivers/clocksource/dw_apb_timer.c +++ b/drivers/clocksource/dw_apb_timer.c @@ -1,13 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * (C) Copyright 2009 Intel Corporation * Author: Jacob Pan (jacob.jun.pan@intel.com) * * Shared with ARM platforms, Jamie Iles, Picochip 2011 * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * * Support for the Synopsys DesignWare APB Timers. */ #include <linux/dw_apb_timer.h> @@ -49,39 +46,31 @@ clocksource_to_dw_apb_clocksource(struct clocksource *cs) return container_of(cs, struct dw_apb_clocksource, cs); } -static unsigned long apbt_readl(struct dw_apb_timer *timer, unsigned long offs) +static inline u32 apbt_readl(struct dw_apb_timer *timer, unsigned long offs) { return readl(timer->base + offs); } -static void apbt_writel(struct dw_apb_timer *timer, unsigned long val, - unsigned long offs) +static inline void apbt_writel(struct dw_apb_timer *timer, u32 val, + unsigned long offs) { writel(val, timer->base + offs); } -static void apbt_disable_int(struct dw_apb_timer *timer) +static inline u32 apbt_readl_relaxed(struct dw_apb_timer *timer, unsigned long offs) { - unsigned long ctrl = apbt_readl(timer, APBTMR_N_CONTROL); - - ctrl |= APBTMR_CONTROL_INT; - apbt_writel(timer, ctrl, APBTMR_N_CONTROL); + return readl_relaxed(timer->base + offs); } -/** - * dw_apb_clockevent_pause() - stop the clock_event_device from running - * - * @dw_ced: The APB clock to stop generating events. - */ -void dw_apb_clockevent_pause(struct dw_apb_clock_event_device *dw_ced) +static inline void apbt_writel_relaxed(struct dw_apb_timer *timer, u32 val, + unsigned long offs) { - disable_irq(dw_ced->timer.irq); - apbt_disable_int(&dw_ced->timer); + writel_relaxed(val, timer->base + offs); } static void apbt_eoi(struct dw_apb_timer *timer) { - apbt_readl(timer, APBTMR_N_EOI); + apbt_readl_relaxed(timer, APBTMR_N_EOI); } static irqreturn_t dw_apb_clockevent_irq(int irq, void *data) @@ -90,7 +79,7 @@ static irqreturn_t dw_apb_clockevent_irq(int irq, void *data) struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt); if (!evt->event_handler) { - pr_info("Spurious APBT timer interrupt %d", irq); + pr_info("Spurious APBT timer interrupt %d\n", irq); return IRQ_NONE; } @@ -103,93 +92,110 @@ static irqreturn_t dw_apb_clockevent_irq(int irq, void *data) static void apbt_enable_int(struct dw_apb_timer *timer) { - unsigned long ctrl = apbt_readl(timer, APBTMR_N_CONTROL); + u32 ctrl = apbt_readl(timer, APBTMR_N_CONTROL); /* clear pending intr */ apbt_readl(timer, APBTMR_N_EOI); ctrl &= ~APBTMR_CONTROL_INT; apbt_writel(timer, ctrl, APBTMR_N_CONTROL); } -static void apbt_set_mode(enum clock_event_mode mode, - struct clock_event_device *evt) +static int apbt_shutdown(struct clock_event_device *evt) { - unsigned long ctrl; - unsigned long period; struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt); + u32 ctrl; - pr_debug("%s CPU %d mode=%d\n", __func__, first_cpu(*evt->cpumask), - mode); - - switch (mode) { - case CLOCK_EVT_MODE_PERIODIC: - period = DIV_ROUND_UP(dw_ced->timer.freq, HZ); - ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); - ctrl |= APBTMR_CONTROL_MODE_PERIODIC; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - /* - * DW APB p. 46, have to disable timer before load counter, - * may cause sync problem. - */ - ctrl &= ~APBTMR_CONTROL_ENABLE; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - udelay(1); - pr_debug("Setting clock period %lu for HZ %d\n", period, HZ); - apbt_writel(&dw_ced->timer, period, APBTMR_N_LOAD_COUNT); - ctrl |= APBTMR_CONTROL_ENABLE; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - break; - - case CLOCK_EVT_MODE_ONESHOT: - ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); - /* - * set free running mode, this mode will let timer reload max - * timeout which will give time (3min on 25MHz clock) to rearm - * the next event, therefore emulate the one-shot mode. - */ - ctrl &= ~APBTMR_CONTROL_ENABLE; - ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC; - - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - /* write again to set free running mode */ - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - - /* - * DW APB p. 46, load counter with all 1s before starting free - * running mode. - */ - apbt_writel(&dw_ced->timer, ~0, APBTMR_N_LOAD_COUNT); - ctrl &= ~APBTMR_CONTROL_INT; - ctrl |= APBTMR_CONTROL_ENABLE; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - break; - - case CLOCK_EVT_MODE_UNUSED: - case CLOCK_EVT_MODE_SHUTDOWN: - ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); - ctrl &= ~APBTMR_CONTROL_ENABLE; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); - break; - - case CLOCK_EVT_MODE_RESUME: - apbt_enable_int(&dw_ced->timer); - break; - } + pr_debug("%s CPU %d state=shutdown\n", __func__, + cpumask_first(evt->cpumask)); + + ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); + ctrl &= ~APBTMR_CONTROL_ENABLE; + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + return 0; +} + +static int apbt_set_oneshot(struct clock_event_device *evt) +{ + struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt); + u32 ctrl; + + pr_debug("%s CPU %d state=oneshot\n", __func__, + cpumask_first(evt->cpumask)); + + ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); + /* + * set free running mode, this mode will let timer reload max + * timeout which will give time (3min on 25MHz clock) to rearm + * the next event, therefore emulate the one-shot mode. + */ + ctrl &= ~APBTMR_CONTROL_ENABLE; + ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC; + + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + /* write again to set free running mode */ + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + + /* + * DW APB p. 46, load counter with all 1s before starting free + * running mode. + */ + apbt_writel(&dw_ced->timer, ~0, APBTMR_N_LOAD_COUNT); + ctrl &= ~APBTMR_CONTROL_INT; + ctrl |= APBTMR_CONTROL_ENABLE; + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + return 0; +} + +static int apbt_set_periodic(struct clock_event_device *evt) +{ + struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt); + unsigned long period = DIV_ROUND_UP(dw_ced->timer.freq, HZ); + u32 ctrl; + + pr_debug("%s CPU %d state=periodic\n", __func__, + cpumask_first(evt->cpumask)); + + ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); + ctrl |= APBTMR_CONTROL_MODE_PERIODIC; + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + /* + * DW APB p. 46, have to disable timer before load counter, + * may cause sync problem. + */ + ctrl &= ~APBTMR_CONTROL_ENABLE; + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + udelay(1); + pr_debug("Setting clock period %lu for HZ %d\n", period, HZ); + apbt_writel(&dw_ced->timer, period, APBTMR_N_LOAD_COUNT); + ctrl |= APBTMR_CONTROL_ENABLE; + apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + return 0; +} + +static int apbt_resume(struct clock_event_device *evt) +{ + struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt); + + pr_debug("%s CPU %d state=resume\n", __func__, + cpumask_first(evt->cpumask)); + + apbt_enable_int(&dw_ced->timer); + return 0; } static int apbt_next_event(unsigned long delta, struct clock_event_device *evt) { - unsigned long ctrl; + u32 ctrl; struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt); /* Disable timer */ - ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL); + ctrl = apbt_readl_relaxed(&dw_ced->timer, APBTMR_N_CONTROL); ctrl &= ~APBTMR_CONTROL_ENABLE; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + apbt_writel_relaxed(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); /* write new count */ - apbt_writel(&dw_ced->timer, delta, APBTMR_N_LOAD_COUNT); + apbt_writel_relaxed(&dw_ced->timer, delta, APBTMR_N_LOAD_COUNT); ctrl |= APBTMR_CONTROL_ENABLE; - apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); + apbt_writel_relaxed(&dw_ced->timer, ctrl, APBTMR_N_CONTROL); return 0; } @@ -197,7 +203,8 @@ static int apbt_next_event(unsigned long delta, /** * dw_apb_clockevent_init() - use an APB timer as a clock_event_device * - * @cpu: The CPU the events will be targeted at. + * @cpu: The CPU the events will be targeted at or -1 if CPU affiliation + * isn't required. * @name: The name used for the timer and the IRQ for it. * @rating: The rating to give the timer. * @base: I/O base for the timer registers. @@ -229,25 +236,26 @@ dw_apb_clockevent_init(int cpu, const char *name, unsigned rating, clockevents_calc_mult_shift(&dw_ced->ced, freq, APBT_MIN_PERIOD); dw_ced->ced.max_delta_ns = clockevent_delta2ns(0x7fffffff, &dw_ced->ced); + dw_ced->ced.max_delta_ticks = 0x7fffffff; dw_ced->ced.min_delta_ns = clockevent_delta2ns(5000, &dw_ced->ced); - dw_ced->ced.cpumask = cpumask_of(cpu); - dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; - dw_ced->ced.set_mode = apbt_set_mode; + dw_ced->ced.min_delta_ticks = 5000; + dw_ced->ced.cpumask = cpu < 0 ? cpu_possible_mask : cpumask_of(cpu); + dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ; + dw_ced->ced.set_state_shutdown = apbt_shutdown; + dw_ced->ced.set_state_periodic = apbt_set_periodic; + dw_ced->ced.set_state_oneshot = apbt_set_oneshot; + dw_ced->ced.set_state_oneshot_stopped = apbt_shutdown; + dw_ced->ced.tick_resume = apbt_resume; dw_ced->ced.set_next_event = apbt_next_event; dw_ced->ced.irq = dw_ced->timer.irq; dw_ced->ced.rating = rating; dw_ced->ced.name = name; - dw_ced->irqaction.name = dw_ced->ced.name; - dw_ced->irqaction.handler = dw_apb_clockevent_irq; - dw_ced->irqaction.dev_id = &dw_ced->ced; - dw_ced->irqaction.irq = irq; - dw_ced->irqaction.flags = IRQF_TIMER | IRQF_IRQPOLL | - IRQF_NOBALANCING | - IRQF_DISABLED; - dw_ced->eoi = apbt_eoi; - err = setup_irq(irq, &dw_ced->irqaction); + err = request_irq(irq, dw_apb_clockevent_irq, + IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING, + dw_ced->ced.name, &dw_ced->ced); if (err) { pr_err("failed to request timer irq\n"); kfree(dw_ced); @@ -258,26 +266,6 @@ dw_apb_clockevent_init(int cpu, const char *name, unsigned rating, } /** - * dw_apb_clockevent_resume() - resume a clock that has been paused. - * - * @dw_ced: The APB clock to resume. - */ -void dw_apb_clockevent_resume(struct dw_apb_clock_event_device *dw_ced) -{ - enable_irq(dw_ced->timer.irq); -} - -/** - * dw_apb_clockevent_stop() - stop the clock_event_device and release the IRQ. - * - * @dw_ced: The APB clock to stop generating the events. - */ -void dw_apb_clockevent_stop(struct dw_apb_clock_event_device *dw_ced) -{ - free_irq(dw_ced->timer.irq, &dw_ced->ced); -} - -/** * dw_apb_clockevent_register() - register the clock with the generic layer * * @dw_ced: The APB clock to register as a clock_event_device. @@ -303,7 +291,7 @@ void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs) * start count down from 0xffff_ffff. this is done by toggling the * enable bit then load initial load count to ~0. */ - unsigned long ctrl = apbt_readl(&dw_cs->timer, APBTMR_N_CONTROL); + u32 ctrl = apbt_readl(&dw_cs->timer, APBTMR_N_CONTROL); ctrl &= ~APBTMR_CONTROL_ENABLE; apbt_writel(&dw_cs->timer, ctrl, APBTMR_N_CONTROL); @@ -316,15 +304,16 @@ void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs) dw_apb_clocksource_read(dw_cs); } -static cycle_t __apbt_read_clocksource(struct clocksource *cs) +static u64 __apbt_read_clocksource(struct clocksource *cs) { - unsigned long current_count; + u32 current_count; struct dw_apb_clocksource *dw_cs = clocksource_to_dw_apb_clocksource(cs); - current_count = apbt_readl(&dw_cs->timer, APBTMR_N_CURRENT_VALUE); + current_count = apbt_readl_relaxed(&dw_cs->timer, + APBTMR_N_CURRENT_VALUE); - return (cycle_t)~current_count; + return (u64)~current_count; } static void apbt_restart_clocksource(struct clocksource *cs) @@ -383,7 +372,7 @@ void dw_apb_clocksource_register(struct dw_apb_clocksource *dw_cs) * * @dw_cs: The clocksource to read. */ -cycle_t dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs) +u64 dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs) { - return (cycle_t)~apbt_readl(&dw_cs->timer, APBTMR_N_CURRENT_VALUE); + return (u64)~apbt_readl(&dw_cs->timer, APBTMR_N_CURRENT_VALUE); } |
