diff options
| -rw-r--r-- | Documentation/devicetree/bindings/timer/efm32,timer.txt | 23 | ||||
| -rw-r--r-- | drivers/clocksource/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/clocksource/Makefile | 1 | ||||
| -rw-r--r-- | drivers/clocksource/em_sti.c | 4 | ||||
| -rw-r--r-- | drivers/clocksource/sun4i_timer.c | 12 | ||||
| -rw-r--r-- | drivers/clocksource/time-efm32.c | 275 |
6 files changed, 317 insertions, 7 deletions
diff --git a/Documentation/devicetree/bindings/timer/efm32,timer.txt b/Documentation/devicetree/bindings/timer/efm32,timer.txt new file mode 100644 index 000000000000..97a568f696c9 --- /dev/null +++ b/Documentation/devicetree/bindings/timer/efm32,timer.txt @@ -0,0 +1,23 @@ +* EFM32 timer hardware + +The efm32 Giant Gecko SoCs come with four 16 bit timers. Two counters can be +connected to form a 32 bit counter. Each timer has three Compare/Capture +channels and can be used as PWM or Quadrature Decoder. Available clock sources +are the cpu's HFPERCLK (with a 10-bit prescaler) or an external pin. + +Required properties: +- compatible : Should be efm32,timer +- reg : Address and length of the register set +- clocks : Should contain a reference to the HFPERCLK + +Optional properties: +- interrupts : Reference to the timer interrupt + +Example: + +timer@40010c00 { + compatible = "efm32,timer"; + reg = <0x40010c00 0x400>; + interrupts = <14>; + clocks = <&cmu clk_HFPERCLKTIMER3>; +}; diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 5e940f839a2d..bdb953e15d2a 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -34,6 +34,7 @@ config ORION_TIMER bool config SUN4I_TIMER + select CLKSRC_MMIO bool config VT8500_TIMER @@ -71,6 +72,14 @@ config CLKSRC_DBX500_PRCMU_SCHED_CLOCK help Use the always on PRCMU Timer as sched_clock +config CLKSRC_EFM32 + bool "Clocksource for Energy Micro's EFM32 SoCs" if !ARCH_EFM32 + depends on OF && ARM && (ARCH_EFM32 || COMPILE_TEST) + default ARCH_EFM32 + help + Support to use the timers of EFM32 SoCs as clock source and clock + event device. + config ARM_ARCH_TIMER bool select CLKSRC_OF if OF diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 704d6d342adc..33621efb9148 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_VT8500_TIMER) += vt8500_timer.o obj-$(CONFIG_ARCH_NSPIRE) += zevio-timer.o obj-$(CONFIG_ARCH_BCM) += bcm_kona_timer.o obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence_ttc_timer.o +obj-$(CONFIG_CLKSRC_EFM32) += time-efm32.o obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o diff --git a/drivers/clocksource/em_sti.c b/drivers/clocksource/em_sti.c index 3a5909c12d42..9d170834fcf3 100644 --- a/drivers/clocksource/em_sti.c +++ b/drivers/clocksource/em_sti.c @@ -78,7 +78,7 @@ static int em_sti_enable(struct em_sti_priv *p) int ret; /* enable clock */ - ret = clk_enable(p->clk); + ret = clk_prepare_enable(p->clk); if (ret) { dev_err(&p->pdev->dev, "cannot enable clock\n"); return ret; @@ -107,7 +107,7 @@ static void em_sti_disable(struct em_sti_priv *p) em_sti_write(p, STI_INTENCLR, 3); /* stop clock */ - clk_disable(p->clk); + clk_disable_unprepare(p->clk); } static cycle_t em_sti_count(struct em_sti_priv *p) diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c index 8ead0258740a..2fb4695a28d8 100644 --- a/drivers/clocksource/sun4i_timer.c +++ b/drivers/clocksource/sun4i_timer.c @@ -37,6 +37,8 @@ #define TIMER_INTVAL_REG(val) (0x10 * (val) + 0x14) #define TIMER_CNTVAL_REG(val) (0x10 * (val) + 0x18) +#define TIMER_SYNC_TICKS 3 + static void __iomem *timer_base; static u32 ticks_per_jiffy; @@ -50,7 +52,7 @@ static void sun4i_clkevt_sync(void) { u32 old = readl(timer_base + TIMER_CNTVAL_REG(1)); - while ((old - readl(timer_base + TIMER_CNTVAL_REG(1))) < 3) + while ((old - readl(timer_base + TIMER_CNTVAL_REG(1))) < TIMER_SYNC_TICKS) cpu_relax(); } @@ -104,7 +106,7 @@ static int sun4i_clkevt_next_event(unsigned long evt, struct clock_event_device *unused) { sun4i_clkevt_time_stop(0); - sun4i_clkevt_time_setup(0, evt); + sun4i_clkevt_time_setup(0, evt - TIMER_SYNC_TICKS); sun4i_clkevt_time_start(0, false); return 0; @@ -131,7 +133,7 @@ static irqreturn_t sun4i_timer_interrupt(int irq, void *dev_id) static struct irqaction sun4i_timer_irq = { .name = "sun4i_timer0", - .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, + .flags = IRQF_TIMER | IRQF_IRQPOLL, .handler = sun4i_timer_interrupt, .dev_id = &sun4i_clockevent, }; @@ -187,8 +189,8 @@ static void __init sun4i_timer_init(struct device_node *node) sun4i_clockevent.cpumask = cpumask_of(0); - clockevents_config_and_register(&sun4i_clockevent, rate, 0x1, - 0xffffffff); + clockevents_config_and_register(&sun4i_clockevent, rate, + TIMER_SYNC_TICKS, 0xffffffff); } CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-timer", sun4i_timer_init); diff --git a/drivers/clocksource/time-efm32.c b/drivers/clocksource/time-efm32.c new file mode 100644 index 000000000000..1a6205b7bed3 --- /dev/null +++ b/drivers/clocksource/time-efm32.c @@ -0,0 +1,275 @@ +/* + * Copyright (C) 2013 Pengutronix + * Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> + * + * 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. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/clk.h> + +#define TIMERn_CTRL 0x00 +#define TIMERn_CTRL_PRESC(val) (((val) & 0xf) << 24) +#define TIMERn_CTRL_PRESC_1024 TIMERn_CTRL_PRESC(10) +#define TIMERn_CTRL_CLKSEL(val) (((val) & 0x3) << 16) +#define TIMERn_CTRL_CLKSEL_PRESCHFPERCLK TIMERn_CTRL_CLKSEL(0) +#define TIMERn_CTRL_OSMEN 0x00000010 +#define TIMERn_CTRL_MODE(val) (((val) & 0x3) << 0) +#define TIMERn_CTRL_MODE_UP TIMERn_CTRL_MODE(0) +#define TIMERn_CTRL_MODE_DOWN TIMERn_CTRL_MODE(1) + +#define TIMERn_CMD 0x04 +#define TIMERn_CMD_START 0x00000001 +#define TIMERn_CMD_STOP 0x00000002 + +#define TIMERn_IEN 0x0c +#define TIMERn_IF 0x10 +#define TIMERn_IFS 0x14 +#define TIMERn_IFC 0x18 +#define TIMERn_IRQ_UF 0x00000002 + +#define TIMERn_TOP 0x1c +#define TIMERn_CNT 0x24 + +struct efm32_clock_event_ddata { + struct clock_event_device evtdev; + void __iomem *base; + unsigned periodic_top; +}; + +static void efm32_clock_event_set_mode(enum clock_event_mode mode, + struct clock_event_device *evtdev) +{ + struct efm32_clock_event_ddata *ddata = + container_of(evtdev, struct efm32_clock_event_ddata, evtdev); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); + writel_relaxed(ddata->periodic_top, ddata->base + TIMERn_TOP); + writel_relaxed(TIMERn_CTRL_PRESC_1024 | + TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | + TIMERn_CTRL_MODE_DOWN, + ddata->base + TIMERn_CTRL); + writel_relaxed(TIMERn_CMD_START, ddata->base + TIMERn_CMD); + break; + + case CLOCK_EVT_MODE_ONESHOT: + writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); + writel_relaxed(TIMERn_CTRL_PRESC_1024 | + TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | + TIMERn_CTRL_OSMEN | + TIMERn_CTRL_MODE_DOWN, + ddata->base + TIMERn_CTRL); + break; + + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); + break; + + case CLOCK_EVT_MODE_RESUME: + break; + } +} + +static int efm32_clock_event_set_next_event(unsigned long evt, + struct clock_event_device *evtdev) +{ + struct efm32_clock_event_ddata *ddata = + container_of(evtdev, struct efm32_clock_event_ddata, evtdev); + + writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); + writel_relaxed(evt, ddata->base + TIMERn_CNT); + writel_relaxed(TIMERn_CMD_START, ddata->base + TIMERn_CMD); + + return 0; +} + +static irqreturn_t efm32_clock_event_handler(int irq, void *dev_id) +{ + struct efm32_clock_event_ddata *ddata = dev_id; + + writel_relaxed(TIMERn_IRQ_UF, ddata->base + TIMERn_IFC); + + ddata->evtdev.event_handler(&ddata->evtdev); + + return IRQ_HANDLED; +} + +static struct efm32_clock_event_ddata clock_event_ddata = { + .evtdev = { + .name = "efm32 clockevent", + .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_MODE_PERIODIC, + .set_mode = efm32_clock_event_set_mode, + .set_next_event = efm32_clock_event_set_next_event, + .rating = 200, + }, +}; + +static struct irqaction efm32_clock_event_irq = { + .name = "efm32 clockevent", + .flags = IRQF_TIMER, + .handler = efm32_clock_event_handler, + .dev_id = &clock_event_ddata, +}; + +static int __init efm32_clocksource_init(struct device_node *np) +{ + struct clk *clk; + void __iomem *base; + unsigned long rate; + int ret; + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clocksource (%d)\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable timer clock for clocksource (%d)\n", + ret); + goto err_clk_enable; + } + rate = clk_get_rate(clk); + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map registers for clocksource\n"); + goto err_iomap; + } + + writel_relaxed(TIMERn_CTRL_PRESC_1024 | + TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | + TIMERn_CTRL_MODE_UP, base + TIMERn_CTRL); + writel_relaxed(TIMERn_CMD_START, base + TIMERn_CMD); + + ret = clocksource_mmio_init(base + TIMERn_CNT, "efm32 timer", + DIV_ROUND_CLOSEST(rate, 1024), 200, 16, + clocksource_mmio_readl_up); + if (ret) { + pr_err("failed to init clocksource (%d)\n", ret); + goto err_clocksource_init; + } + + return 0; + +err_clocksource_init: + + iounmap(base); +err_iomap: + + clk_disable_unprepare(clk); +err_clk_enable: + + clk_put(clk); +err_clk_get: + + return ret; +} + +static int __init efm32_clockevent_init(struct device_node *np) +{ + struct clk *clk; + void __iomem *base; + unsigned long rate; + int irq; + int ret; + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) { + ret = PTR_ERR(clk); + pr_err("failed to get clock for clockevent (%d)\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(clk); + if (ret) { + pr_err("failed to enable timer clock for clockevent (%d)\n", + ret); + goto err_clk_enable; + } + rate = clk_get_rate(clk); + + base = of_iomap(np, 0); + if (!base) { + ret = -EADDRNOTAVAIL; + pr_err("failed to map registers for clockevent\n"); + goto err_iomap; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -ENOENT; + pr_err("failed to get irq for clockevent\n"); + goto err_get_irq; + } + + writel_relaxed(TIMERn_IRQ_UF, base + TIMERn_IEN); + + clock_event_ddata.base = base; + clock_event_ddata.periodic_top = DIV_ROUND_CLOSEST(rate, 1024 * HZ); + + setup_irq(irq, &efm32_clock_event_irq); + + clockevents_config_and_register(&clock_event_ddata.evtdev, + DIV_ROUND_CLOSEST(rate, 1024), + 0xf, 0xffff); + + return 0; + +err_get_irq: + + iounmap(base); +err_iomap: + + clk_disable_unprepare(clk); +err_clk_enable: + + clk_put(clk); +err_clk_get: + + return ret; +} + +/* + * This function asserts that we have exactly one clocksource and one + * clock_event_device in the end. + */ +static void __init efm32_timer_init(struct device_node *np) +{ + static int has_clocksource, has_clockevent; + int ret; + + if (!has_clocksource) { + ret = efm32_clocksource_init(np); + if (!ret) { + has_clocksource = 1; + return; + } + } + + if (!has_clockevent) { + ret = efm32_clockevent_init(np); + if (!ret) { + has_clockevent = 1; + return; + } + } +} +CLOCKSOURCE_OF_DECLARE(efm32, "efm32,timer", efm32_timer_init); 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