diff options
Diffstat (limited to 'drivers/clocksource')
| -rw-r--r-- | drivers/clocksource/Kconfig | 16 | ||||
| -rw-r--r-- | drivers/clocksource/Makefile | 2 | ||||
| -rw-r--r-- | drivers/clocksource/timer-cadence-ttc.c | 4 | ||||
| -rw-r--r-- | drivers/clocksource/timer-clint.c | 243 | ||||
| -rw-r--r-- | drivers/clocksource/timer-riscv.c | 17 | ||||
| -rw-r--r-- | drivers/clocksource/timer-stm32-lp.c | 221 |
6 files changed, 484 insertions, 19 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 2ed8b4361d95..68b087bff59c 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -291,6 +291,10 @@ config CLKSRC_STM32 select CLKSRC_MMIO select TIMER_OF +config CLKSRC_STM32_LP + bool "Low power clocksource for STM32 SoCs" + depends on MFD_STM32_LPTIMER || COMPILE_TEST + config CLKSRC_MPS2 bool "Clocksource for MPS2 SoCs" if COMPILE_TEST depends on GENERIC_SCHED_CLOCK @@ -649,9 +653,8 @@ config ATCPIT100_TIMER This option enables support for the Andestech ATCPIT100 timers. config RISCV_TIMER - bool "Timer for the RISC-V platform" + bool "Timer for the RISC-V platform" if COMPILE_TEST depends on GENERIC_SCHED_CLOCK && RISCV - default y select TIMER_PROBE select TIMER_OF help @@ -659,6 +662,15 @@ config RISCV_TIMER is accessed via both the SBI and the rdcycle instruction. This is required for all RISC-V systems. +config CLINT_TIMER + bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST + depends on GENERIC_SCHED_CLOCK && RISCV + select TIMER_PROBE + select TIMER_OF + help + This option enables the CLINT timer for RISC-V systems. The CLINT + driver is usually used for NoMMU RISC-V systems. + config CSKY_MP_TIMER bool "SMP Timer for the C-SKY platform" if COMPILE_TEST depends on CSKY diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 3994e221e262..1c444cc3bb44 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -45,6 +45,7 @@ obj-$(CONFIG_BCM_KONA_TIMER) += bcm_kona_timer.o obj-$(CONFIG_CADENCE_TTC_TIMER) += timer-cadence-ttc.o obj-$(CONFIG_CLKSRC_EFM32) += timer-efm32.o obj-$(CONFIG_CLKSRC_STM32) += timer-stm32.o +obj-$(CONFIG_CLKSRC_STM32_LP) += timer-stm32-lp.o obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o obj-$(CONFIG_CLKSRC_LPC32XX) += timer-lpc32xx.o obj-$(CONFIG_CLKSRC_MPS2) += mps2-timer.o @@ -88,6 +89,7 @@ obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o obj-$(CONFIG_X86_NUMACHIP) += numachip.o obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o +obj-$(CONFIG_CLINT_TIMER) += timer-clint.o obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o obj-$(CONFIG_HYPERV_TIMER) += hyperv_timer.o diff --git a/drivers/clocksource/timer-cadence-ttc.c b/drivers/clocksource/timer-cadence-ttc.c index 38858e141731..80e960602030 100644 --- a/drivers/clocksource/timer-cadence-ttc.c +++ b/drivers/clocksource/timer-cadence-ttc.c @@ -309,7 +309,7 @@ static int ttc_rate_change_clocksource_cb(struct notifier_block *nb, /* restore original register value */ writel_relaxed(ttccs->scale_clk_ctrl_reg_old, ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET); - /* fall through */ + fallthrough; default: return NOTIFY_DONE; } @@ -392,7 +392,7 @@ static int ttc_rate_change_clockevent_cb(struct notifier_block *nb, clockevents_update_freq(&ttcce->ce, ndata->new_rate / PRESCALE); - /* fall through */ + fallthrough; case PRE_RATE_CHANGE: case ABORT_RATE_CHANGE: default: diff --git a/drivers/clocksource/timer-clint.c b/drivers/clocksource/timer-clint.c new file mode 100644 index 000000000000..d17367dee02c --- /dev/null +++ b/drivers/clocksource/timer-clint.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Western Digital Corporation or its affiliates. + * + * Most of the M-mode (i.e. NoMMU) RISC-V systems usually have a + * CLINT MMIO timer device. + */ + +#define pr_fmt(fmt) "clint: " fmt +#include <linux/bitops.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/cpu.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/sched_clock.h> +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/interrupt.h> +#include <linux/of_irq.h> +#include <linux/smp.h> +#include <linux/timex.h> + +#ifndef CONFIG_RISCV_M_MODE +#include <asm/clint.h> +#endif + +#define CLINT_IPI_OFF 0 +#define CLINT_TIMER_CMP_OFF 0x4000 +#define CLINT_TIMER_VAL_OFF 0xbff8 + +/* CLINT manages IPI and Timer for RISC-V M-mode */ +static u32 __iomem *clint_ipi_base; +static u64 __iomem *clint_timer_cmp; +static u64 __iomem *clint_timer_val; +static unsigned long clint_timer_freq; +static unsigned int clint_timer_irq; + +#ifdef CONFIG_RISCV_M_MODE +u64 __iomem *clint_time_val; +#endif + +static void clint_send_ipi(const struct cpumask *target) +{ + unsigned int cpu; + + for_each_cpu(cpu, target) + writel(1, clint_ipi_base + cpuid_to_hartid_map(cpu)); +} + +static void clint_clear_ipi(void) +{ + writel(0, clint_ipi_base + cpuid_to_hartid_map(smp_processor_id())); +} + +static struct riscv_ipi_ops clint_ipi_ops = { + .ipi_inject = clint_send_ipi, + .ipi_clear = clint_clear_ipi, +}; + +#ifdef CONFIG_64BIT +#define clint_get_cycles() readq_relaxed(clint_timer_val) +#else +#define clint_get_cycles() readl_relaxed(clint_timer_val) +#define clint_get_cycles_hi() readl_relaxed(((u32 *)clint_timer_val) + 1) +#endif + +#ifdef CONFIG_64BIT +static u64 notrace clint_get_cycles64(void) +{ + return clint_get_cycles(); +} +#else /* CONFIG_64BIT */ +static u64 notrace clint_get_cycles64(void) +{ + u32 hi, lo; + + do { + hi = clint_get_cycles_hi(); + lo = clint_get_cycles(); + } while (hi != clint_get_cycles_hi()); + + return ((u64)hi << 32) | lo; +} +#endif /* CONFIG_64BIT */ + +static u64 clint_rdtime(struct clocksource *cs) +{ + return clint_get_cycles64(); +} + +static struct clocksource clint_clocksource = { + .name = "clint_clocksource", + .rating = 300, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .read = clint_rdtime, +}; + +static int clint_clock_next_event(unsigned long delta, + struct clock_event_device *ce) +{ + void __iomem *r = clint_timer_cmp + + cpuid_to_hartid_map(smp_processor_id()); + + csr_set(CSR_IE, IE_TIE); + writeq_relaxed(clint_get_cycles64() + delta, r); + return 0; +} + +static DEFINE_PER_CPU(struct clock_event_device, clint_clock_event) = { + .name = "clint_clockevent", + .features = CLOCK_EVT_FEAT_ONESHOT, + .rating = 100, + .set_next_event = clint_clock_next_event, +}; + +static int clint_timer_starting_cpu(unsigned int cpu) +{ + struct clock_event_device *ce = per_cpu_ptr(&clint_clock_event, cpu); + + ce->cpumask = cpumask_of(cpu); + clockevents_config_and_register(ce, clint_timer_freq, 100, 0x7fffffff); + + enable_percpu_irq(clint_timer_irq, + irq_get_trigger_type(clint_timer_irq)); + return 0; +} + +static int clint_timer_dying_cpu(unsigned int cpu) +{ + disable_percpu_irq(clint_timer_irq); + return 0; +} + +static irqreturn_t clint_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evdev = this_cpu_ptr(&clint_clock_event); + + csr_clear(CSR_IE, IE_TIE); + evdev->event_handler(evdev); + + return IRQ_HANDLED; +} + +static int __init clint_timer_init_dt(struct device_node *np) +{ + int rc; + u32 i, nr_irqs; + void __iomem *base; + struct of_phandle_args oirq; + + /* + * Ensure that CLINT device interrupts are either RV_IRQ_TIMER or + * RV_IRQ_SOFT. If it's anything else then we ignore the device. + */ + nr_irqs = of_irq_count(np); + for (i = 0; i < nr_irqs; i++) { + if (of_irq_parse_one(np, i, &oirq)) { + pr_err("%pOFP: failed to parse irq %d.\n", np, i); + continue; + } + + if ((oirq.args_count != 1) || + (oirq.args[0] != RV_IRQ_TIMER && + oirq.args[0] != RV_IRQ_SOFT)) { + pr_err("%pOFP: invalid irq %d (hwirq %d)\n", + np, i, oirq.args[0]); + return -ENODEV; + } + + /* Find parent irq domain and map timer irq */ + if (!clint_timer_irq && + oirq.args[0] == RV_IRQ_TIMER && + irq_find_host(oirq.np)) + clint_timer_irq = irq_of_parse_and_map(np, i); + } + + /* If CLINT timer irq not found then fail */ + if (!clint_timer_irq) { + pr_err("%pOFP: timer irq not found\n", np); + return -ENODEV; + } + + base = of_iomap(np, 0); + if (!base) { + pr_err("%pOFP: could not map registers\n", np); + return -ENODEV; + } + + clint_ipi_base = base + CLINT_IPI_OFF; + clint_timer_cmp = base + CLINT_TIMER_CMP_OFF; + clint_timer_val = base + CLINT_TIMER_VAL_OFF; + clint_timer_freq = riscv_timebase; + +#ifdef CONFIG_RISCV_M_MODE + /* + * Yes, that's an odd naming scheme. time_val is public, but hopefully + * will die in favor of something cleaner. + */ + clint_time_val = clint_timer_val; +#endif + + pr_info("%pOFP: timer running at %ld Hz\n", np, clint_timer_freq); + + rc = clocksource_register_hz(&clint_clocksource, clint_timer_freq); + if (rc) { + pr_err("%pOFP: clocksource register failed [%d]\n", np, rc); + goto fail_iounmap; + } + + sched_clock_register(clint_get_cycles64, 64, clint_timer_freq); + + rc = request_percpu_irq(clint_timer_irq, clint_timer_interrupt, + "clint-timer", &clint_clock_event); + if (rc) { + pr_err("registering percpu irq failed [%d]\n", rc); + goto fail_iounmap; + } + + rc = cpuhp_setup_state(CPUHP_AP_CLINT_TIMER_STARTING, + "clockevents/clint/timer:starting", + clint_timer_starting_cpu, + clint_timer_dying_cpu); + if (rc) { + pr_err("%pOFP: cpuhp setup state failed [%d]\n", np, rc); + goto fail_free_irq; + } + + riscv_set_ipi_ops(&clint_ipi_ops); + clint_clear_ipi(); + + return 0; + +fail_free_irq: + free_irq(clint_timer_irq, &clint_clock_event); +fail_iounmap: + iounmap(base); + return rc; +} + +TIMER_OF_DECLARE(clint_timer, "riscv,clint0", clint_timer_init_dt); +TIMER_OF_DECLARE(clint_timer1, "sifive,clint0", clint_timer_init_dt); diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c index 9de1dabfb126..c51c5ed15aa7 100644 --- a/drivers/clocksource/timer-riscv.c +++ b/drivers/clocksource/timer-riscv.c @@ -19,26 +19,13 @@ #include <linux/of_irq.h> #include <asm/smp.h> #include <asm/sbi.h> - -u64 __iomem *riscv_time_cmp; -u64 __iomem *riscv_time_val; - -static inline void mmio_set_timer(u64 val) -{ - void __iomem *r; - - r = riscv_time_cmp + cpuid_to_hartid_map(smp_processor_id()); - writeq_relaxed(val, r); -} +#include <asm/timex.h> static int riscv_clock_next_event(unsigned long delta, struct clock_event_device *ce) { csr_set(CSR_IE, IE_TIE); - if (IS_ENABLED(CONFIG_RISCV_SBI)) - sbi_set_timer(get_cycles64() + delta); - else - mmio_set_timer(get_cycles64() + delta); + sbi_set_timer(get_cycles64() + delta); return 0; } diff --git a/drivers/clocksource/timer-stm32-lp.c b/drivers/clocksource/timer-stm32-lp.c new file mode 100644 index 000000000000..db2841d0beb8 --- /dev/null +++ b/drivers/clocksource/timer-stm32-lp.c @@ -0,0 +1,221 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) STMicroelectronics 2019 - All Rights Reserved + * Authors: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics. + * Pascal Paillet <p.paillet@st.com> for STMicroelectronics. + */ + +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/mfd/stm32-lptimer.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/platform_device.h> +#include <linux/pm_wakeirq.h> + +#define CFGR_PSC_OFFSET 9 +#define STM32_LP_RATING 1000 +#define STM32_TARGET_CLKRATE (32000 * HZ) +#define STM32_LP_MAX_PSC 7 + +struct stm32_lp_private { + struct regmap *reg; + struct clock_event_device clkevt; + unsigned long period; + struct device *dev; +}; + +static struct stm32_lp_private* +to_priv(struct clock_event_device *clkevt) +{ + return container_of(clkevt, struct stm32_lp_private, clkevt); +} + +static int stm32_clkevent_lp_shutdown(struct clock_event_device *clkevt) +{ + struct stm32_lp_private *priv = to_priv(clkevt); + + regmap_write(priv->reg, STM32_LPTIM_CR, 0); + regmap_write(priv->reg, STM32_LPTIM_IER, 0); + /* clear pending flags */ + regmap_write(priv->reg, STM32_LPTIM_ICR, STM32_LPTIM_ARRMCF); + + return 0; +} + +static int stm32_clkevent_lp_set_timer(unsigned long evt, + struct clock_event_device *clkevt, + int is_periodic) +{ + struct stm32_lp_private *priv = to_priv(clkevt); + + /* disable LPTIMER to be able to write into IER register*/ + regmap_write(priv->reg, STM32_LPTIM_CR, 0); + /* enable ARR interrupt */ + regmap_write(priv->reg, STM32_LPTIM_IER, STM32_LPTIM_ARRMIE); + /* enable LPTIMER to be able to write into ARR register */ + regmap_write(priv->reg, STM32_LPTIM_CR, STM32_LPTIM_ENABLE); + /* set next event counter */ + regmap_write(priv->reg, STM32_LPTIM_ARR, evt); + + /* start counter */ + if (is_periodic) + regmap_write(priv->reg, STM32_LPTIM_CR, + STM32_LPTIM_CNTSTRT | STM32_LPTIM_ENABLE); + else + regmap_write(priv->reg, STM32_LPTIM_CR, + STM32_LPTIM_SNGSTRT | STM32_LPTIM_ENABLE); + + return 0; +} + +static int stm32_clkevent_lp_set_next_event(unsigned long evt, + struct clock_event_device *clkevt) +{ + return stm32_clkevent_lp_set_timer(evt, clkevt, + clockevent_state_periodic(clkevt)); +} + +static int stm32_clkevent_lp_set_periodic(struct clock_event_device *clkevt) +{ + struct stm32_lp_private *priv = to_priv(clkevt); + + return stm32_clkevent_lp_set_timer(priv->period, clkevt, true); +} + +static int stm32_clkevent_lp_set_oneshot(struct clock_event_device *clkevt) +{ + struct stm32_lp_private *priv = to_priv(clkevt); + + return stm32_clkevent_lp_set_timer(priv->period, clkevt, false); +} + +static irqreturn_t stm32_clkevent_lp_irq_handler(int irq, void *dev_id) +{ + struct clock_event_device *clkevt = (struct clock_event_device *)dev_id; + struct stm32_lp_private *priv = to_priv(clkevt); + + regmap_write(priv->reg, STM32_LPTIM_ICR, STM32_LPTIM_ARRMCF); + + if (clkevt->event_handler) + clkevt->event_handler(clkevt); + + return IRQ_HANDLED; +} + +static void stm32_clkevent_lp_set_prescaler(struct stm32_lp_private *priv, + unsigned long *rate) +{ + int i; + + for (i = 0; i <= STM32_LP_MAX_PSC; i++) { + if (DIV_ROUND_CLOSEST(*rate, 1 << i) < STM32_TARGET_CLKRATE) + break; + } + + regmap_write(priv->reg, STM32_LPTIM_CFGR, i << CFGR_PSC_OFFSET); + + /* Adjust rate and period given the prescaler value */ + *rate = DIV_ROUND_CLOSEST(*rate, (1 << i)); + priv->period = DIV_ROUND_UP(*rate, HZ); +} + +static void stm32_clkevent_lp_init(struct stm32_lp_private *priv, + struct device_node *np, unsigned long rate) +{ + priv->clkevt.name = np->full_name; + priv->clkevt.cpumask = cpu_possible_mask; + priv->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT; + priv->clkevt.set_state_shutdown = stm32_clkevent_lp_shutdown; + priv->clkevt.set_state_periodic = stm32_clkevent_lp_set_periodic; + priv->clkevt.set_state_oneshot = stm32_clkevent_lp_set_oneshot; + priv->clkevt.set_next_event = stm32_clkevent_lp_set_next_event; + priv->clkevt.rating = STM32_LP_RATING; + + clockevents_config_and_register(&priv->clkevt, rate, 0x1, + STM32_LPTIM_MAX_ARR); +} + +static int stm32_clkevent_lp_probe(struct platform_device *pdev) +{ + struct stm32_lptimer *ddata = dev_get_drvdata(pdev->dev.parent); + struct stm32_lp_private *priv; + unsigned long rate; + int ret, irq; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->reg = ddata->regmap; + ret = clk_prepare_enable(ddata->clk); + if (ret) + return -EINVAL; + + rate = clk_get_rate(ddata->clk); + if (!rate) { + ret = -EINVAL; + goto out_clk_disable; + } + + irq = platform_get_irq(to_platform_device(pdev->dev.parent), 0); + if (irq <= 0) { + ret = irq; + goto out_clk_disable; + } + + if (of_property_read_bool(pdev->dev.parent->of_node, "wakeup-source")) { + ret = device_init_wakeup(&pdev->dev, true); + if (ret) + goto out_clk_disable; + + ret = dev_pm_set_wake_irq(&pdev->dev, irq); + if (ret) + goto out_clk_disable; + } + + ret = devm_request_irq(&pdev->dev, irq, stm32_clkevent_lp_irq_handler, + IRQF_TIMER, pdev->name, &priv->clkevt); + if (ret) + goto out_clk_disable; + + stm32_clkevent_lp_set_prescaler(priv, &rate); + + stm32_clkevent_lp_init(priv, pdev->dev.parent->of_node, rate); + + priv->dev = &pdev->dev; + + return 0; + +out_clk_disable: + clk_disable_unprepare(ddata->clk); + return ret; +} + +static int stm32_clkevent_lp_remove(struct platform_device *pdev) +{ + return -EBUSY; /* cannot unregister clockevent */ +} + +static const struct of_device_id stm32_clkevent_lp_of_match[] = { + { .compatible = "st,stm32-lptimer-timer", }, + {}, +}; +MODULE_DEVICE_TABLE(of, stm32_clkevent_lp_of_match); + +static struct platform_driver stm32_clkevent_lp_driver = { + .probe = stm32_clkevent_lp_probe, + .remove = stm32_clkevent_lp_remove, + .driver = { + .name = "stm32-lptimer-timer", + .of_match_table = of_match_ptr(stm32_clkevent_lp_of_match), + }, +}; +module_platform_driver(stm32_clkevent_lp_driver); + +MODULE_ALIAS("platform:stm32-lptimer-timer"); +MODULE_DESCRIPTION("STMicroelectronics STM32 clockevent low power driver"); +MODULE_LICENSE("GPL v2"); |