From 7cb47848f8a10aed6e050c0ea483b4bb5eaa62a4 Mon Sep 17 00:00:00 2001 From: Xingyu Wu Date: Thu, 19 Oct 2023 13:35:00 +0800 Subject: [PATCH 003/116] clocksource: Add JH7110 timer driver Add timer driver for the StarFive JH7110 SoC. Signed-off-by: Xingyu Wu --- drivers/clocksource/Kconfig | 11 + drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-jh7110.c | 380 +++++++++++++++++++++++++++++ 3 files changed, 392 insertions(+) create mode 100644 drivers/clocksource/timer-jh7110.c --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -642,6 +642,17 @@ config RISCV_TIMER is accessed via both the SBI and the rdcycle instruction. This is required for all RISC-V systems. +config STARFIVE_JH7110_TIMER + bool "Timer for the STARFIVE JH7110 SoC" + depends on ARCH_STARFIVE || COMPILE_TEST + select TIMER_OF + select CLKSRC_MMIO + default ARCH_STARFIVE + help + This enables the timer for StarFive JH7110 SoC. On RISC-V platform, + the system has started RISCV_TIMER, but you can also use this timer + which can provide four channels to do a lot more things on JH7110 SoC. + config CLINT_TIMER bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST depends on GENERIC_SCHED_CLOCK && RISCV --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -80,6 +80,7 @@ obj-$(CONFIG_INGENIC_TIMER) += ingenic- obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o obj-$(CONFIG_X86_NUMACHIP) += numachip.o obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o +obj-$(CONFIG_STARFIVE_JH7110_TIMER) += timer-jh7110.o obj-$(CONFIG_CLINT_TIMER) += timer-clint.o obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o --- /dev/null +++ b/drivers/clocksource/timer-jh7110.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Starfive JH7110 Timer driver + * + * Copyright (C) 2022-2023 StarFive Technology Co., Ltd. + * + * Author: + * Xingyu Wu + * Samin Guo + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* Bias: Ch0-0x0, Ch1-0x40, Ch2-0x80, and so on. */ +#define JH7110_TIMER_CH_LEN 0x40 +#define JH7110_TIMER_CH_BASE(x) ((x) * JH7110_TIMER_CH_LEN) +#define JH7110_TIMER_CH_MAX 4 + +#define JH7110_CLOCK_SOURCE_RATING 200 +#define JH7110_VALID_BITS 32 +#define JH7110_DELAY_US 0 +#define JH7110_TIMEOUT_US 10000 +#define JH7110_CLOCKEVENT_RATING 300 +#define JH7110_TIMER_MAX_TICKS 0xffffffff +#define JH7110_TIMER_MIN_TICKS 0xf +#define JH7110_TIMER_RELOAD_VALUE 0 + +#define JH7110_TIMER_INT_STATUS 0x00 /* RO[0:4]: Interrupt Status for channel0~4 */ +#define JH7110_TIMER_CTL 0x04 /* RW[0]: 0-continuous run, 1-single run */ +#define JH7110_TIMER_LOAD 0x08 /* RW: load value to counter */ +#define JH7110_TIMER_ENABLE 0x10 /* RW[0]: timer enable register */ +#define JH7110_TIMER_RELOAD 0x14 /* RW: write 1 or 0 both reload counter */ +#define JH7110_TIMER_VALUE 0x18 /* RO: timer value register */ +#define JH7110_TIMER_INT_CLR 0x20 /* RW: timer interrupt clear register */ +#define JH7110_TIMER_INT_MASK 0x24 /* RW[0]: timer interrupt mask register */ + +#define JH7110_TIMER_INT_CLR_ENA BIT(0) +#define JH7110_TIMER_INT_CLR_AVA_MASK BIT(1) + +struct jh7110_clkevt { + struct clock_event_device evt; + struct clocksource cs; + bool cs_is_valid; + struct clk *clk; + struct reset_control *rst; + u32 rate; + u32 reload_val; + void __iomem *base; + char name[sizeof("jh7110-timer.chX")]; +}; + +struct jh7110_timer_priv { + struct clk *pclk; + struct reset_control *prst; + struct jh7110_clkevt clkevt[JH7110_TIMER_CH_MAX]; +}; + +/* 0:continuous-run mode, 1:single-run mode */ +enum jh7110_timer_mode { + JH7110_TIMER_MODE_CONTIN, + JH7110_TIMER_MODE_SINGLE, +}; + +/* Interrupt Mask, 0:Unmask, 1:Mask */ +enum jh7110_timer_int_mask { + JH7110_TIMER_INT_ENA, + JH7110_TIMER_INT_DIS, +}; + +enum jh7110_timer_enable { + JH7110_TIMER_DIS, + JH7110_TIMER_ENA, +}; + +static inline struct jh7110_clkevt *to_jh7110_clkevt(struct clock_event_device *evt) +{ + return container_of(evt, struct jh7110_clkevt, evt); +} + +/* + * BIT(0): Read value represent channel int status. + * Write 1 to this bit to clear interrupt. Write 0 has no effects. + * BIT(1): "1" means that it is clearing interrupt. BIT(0) can not be written. + */ +static inline int jh7110_timer_int_clear(struct jh7110_clkevt *clkevt) +{ + u32 value; + int ret; + + /* Waiting interrupt can be cleared */ + ret = readl_poll_timeout_atomic(clkevt->base + JH7110_TIMER_INT_CLR, value, + !(value & JH7110_TIMER_INT_CLR_AVA_MASK), + JH7110_DELAY_US, JH7110_TIMEOUT_US); + if (!ret) + writel(JH7110_TIMER_INT_CLR_ENA, clkevt->base + JH7110_TIMER_INT_CLR); + + return ret; +} + +static int jh7110_timer_start(struct jh7110_clkevt *clkevt) +{ + int ret; + + /* Disable and clear interrupt first */ + writel(JH7110_TIMER_INT_DIS, clkevt->base + JH7110_TIMER_INT_MASK); + ret = jh7110_timer_int_clear(clkevt); + if (ret) + return ret; + + writel(JH7110_TIMER_INT_ENA, clkevt->base + JH7110_TIMER_INT_MASK); + writel(JH7110_TIMER_ENA, clkevt->base + JH7110_TIMER_ENABLE); + + return 0; +} + +static int jh7110_timer_shutdown(struct clock_event_device *evt) +{ + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + + writel(JH7110_TIMER_DIS, clkevt->base + JH7110_TIMER_ENABLE); + return jh7110_timer_int_clear(clkevt); +} + +static void jh7110_timer_suspend(struct clock_event_device *evt) +{ + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + + clkevt->reload_val = readl(clkevt->base + JH7110_TIMER_LOAD); + jh7110_timer_shutdown(evt); +} + +static void jh7110_timer_resume(struct clock_event_device *evt) +{ + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + + writel(clkevt->reload_val, clkevt->base + JH7110_TIMER_LOAD); + writel(JH7110_TIMER_RELOAD_VALUE, clkevt->base + JH7110_TIMER_RELOAD); + jh7110_timer_start(clkevt); +} + +static int jh7110_timer_tick_resume(struct clock_event_device *evt) +{ + jh7110_timer_resume(evt); + + return 0; +} + +/* IRQ handler for the timer */ +static irqreturn_t jh7110_timer_interrupt(int irq, void *priv) +{ + struct clock_event_device *evt = (struct clock_event_device *)priv; + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + + if (jh7110_timer_int_clear(clkevt)) + return IRQ_NONE; + + if (evt->event_handler) + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static int jh7110_timer_set_periodic(struct clock_event_device *evt) +{ + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + u32 periodic = DIV_ROUND_CLOSEST(clkevt->rate, HZ); + + writel(JH7110_TIMER_MODE_CONTIN, clkevt->base + JH7110_TIMER_CTL); + writel(periodic, clkevt->base + JH7110_TIMER_LOAD); + + return jh7110_timer_start(clkevt); +} + +static int jh7110_timer_set_oneshot(struct clock_event_device *evt) +{ + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + + writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL); + writel(JH7110_TIMER_MAX_TICKS, clkevt->base + JH7110_TIMER_LOAD); + + return jh7110_timer_start(clkevt); +} + +static int jh7110_timer_set_next_event(unsigned long next, + struct clock_event_device *evt) +{ + struct jh7110_clkevt *clkevt = to_jh7110_clkevt(evt); + + writel(JH7110_TIMER_MODE_SINGLE, clkevt->base + JH7110_TIMER_CTL); + writel(next, clkevt->base + JH7110_TIMER_LOAD); + + return jh7110_timer_start(clkevt); +} + +static void jh7110_set_clockevent(struct clock_event_device *evt) +{ + evt->features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT | + CLOCK_EVT_FEAT_DYNIRQ; + evt->set_state_shutdown = jh7110_timer_shutdown; + evt->set_state_periodic = jh7110_timer_set_periodic; + evt->set_state_oneshot = jh7110_timer_set_oneshot; + evt->set_state_oneshot_stopped = jh7110_timer_shutdown; + evt->tick_resume = jh7110_timer_tick_resume; + evt->set_next_event = jh7110_timer_set_next_event; + evt->suspend = jh7110_timer_suspend; + evt->resume = jh7110_timer_resume; + evt->rating = JH7110_CLOCKEVENT_RATING; +} + +static u64 jh7110_timer_clocksource_read(struct clocksource *cs) +{ + struct jh7110_clkevt *clkevt = container_of(cs, struct jh7110_clkevt, cs); + + return (u64)readl(clkevt->base + JH7110_TIMER_VALUE); +} + +static int jh7110_clocksource_init(struct jh7110_clkevt *clkevt) +{ + int ret; + + clkevt->cs.name = clkevt->name; + clkevt->cs.rating = JH7110_CLOCK_SOURCE_RATING; + clkevt->cs.read = jh7110_timer_clocksource_read; + clkevt->cs.mask = CLOCKSOURCE_MASK(JH7110_VALID_BITS); + clkevt->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS; + + ret = clocksource_register_hz(&clkevt->cs, clkevt->rate); + if (ret) + return ret; + + clkevt->cs_is_valid = true; /* clocksource register done */ + writel(JH7110_TIMER_MODE_CONTIN, clkevt->base + JH7110_TIMER_CTL); + writel(JH7110_TIMER_MAX_TICKS, clkevt->base + JH7110_TIMER_LOAD); + + return jh7110_timer_start(clkevt); +} + +static void jh7110_clockevents_register(struct jh7110_clkevt *clkevt) +{ + clkevt->rate = clk_get_rate(clkevt->clk); + + jh7110_set_clockevent(&clkevt->evt); + clkevt->evt.name = clkevt->name; + clkevt->evt.cpumask = cpu_possible_mask; + + clockevents_config_and_register(&clkevt->evt, clkevt->rate, + JH7110_TIMER_MIN_TICKS, JH7110_TIMER_MAX_TICKS); +} + +static void jh7110_timer_release(void *data) +{ + struct jh7110_timer_priv *priv = data; + int i; + + for (i = 0; i < JH7110_TIMER_CH_MAX; i++) { + /* Disable each channel of timer */ + if (priv->clkevt[i].base) + writel(JH7110_TIMER_DIS, priv->clkevt[i].base + JH7110_TIMER_ENABLE); + + /* Avoid no initialization in the loop of the probe */ + if (!IS_ERR_OR_NULL(priv->clkevt[i].rst)) + reset_control_assert(priv->clkevt[i].rst); + + if (priv->clkevt[i].cs_is_valid) + clocksource_unregister(&priv->clkevt[i].cs); + } + + reset_control_assert(priv->prst); +} + +static int jh7110_timer_probe(struct platform_device *pdev) +{ + struct jh7110_timer_priv *priv; + struct jh7110_clkevt *clkevt; + char name[sizeof("chX")]; + int ch; + int ret; + void __iomem *base; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return dev_err_probe(&pdev->dev, PTR_ERR(base), + "failed to map registers\n"); + + priv->prst = devm_reset_control_get_exclusive(&pdev->dev, "apb"); + if (IS_ERR(priv->prst)) + return dev_err_probe(&pdev->dev, PTR_ERR(priv->prst), + "failed to get apb reset\n"); + + priv->pclk = devm_clk_get_enabled(&pdev->dev, "apb"); + if (IS_ERR(priv->pclk)) + return dev_err_probe(&pdev->dev, PTR_ERR(priv->pclk), + "failed to get & enable apb clock\n"); + + ret = reset_control_deassert(priv->prst); + if (ret) + return dev_err_probe(&pdev->dev, ret, "failed to deassert apb reset\n"); + + ret = devm_add_action_or_reset(&pdev->dev, jh7110_timer_release, priv); + if (ret) + return ret; + + for (ch = 0; ch < JH7110_TIMER_CH_MAX; ch++) { + clkevt = &priv->clkevt[ch]; + snprintf(name, sizeof(name), "ch%d", ch); + + clkevt->base = base + JH7110_TIMER_CH_BASE(ch); + /* Ensure timer is disabled */ + writel(JH7110_TIMER_DIS, clkevt->base + JH7110_TIMER_ENABLE); + + clkevt->rst = devm_reset_control_get_exclusive(&pdev->dev, name); + if (IS_ERR(clkevt->rst)) + return PTR_ERR(clkevt->rst); + + clkevt->clk = devm_clk_get_enabled(&pdev->dev, name); + if (IS_ERR(clkevt->clk)) + return PTR_ERR(clkevt->clk); + + ret = reset_control_deassert(clkevt->rst); + if (ret) + return ret; + + clkevt->evt.irq = platform_get_irq(pdev, ch); + if (clkevt->evt.irq < 0) + return clkevt->evt.irq; + + snprintf(clkevt->name, sizeof(clkevt->name), "jh7110-timer.ch%d", ch); + jh7110_clockevents_register(clkevt); + + ret = devm_request_irq(&pdev->dev, clkevt->evt.irq, jh7110_timer_interrupt, + IRQF_TIMER | IRQF_IRQPOLL, + clkevt->name, &clkevt->evt); + if (ret) + return ret; + + ret = jh7110_clocksource_init(clkevt); + if (ret) + return ret; + } + + return 0; +} + +static const struct of_device_id jh7110_timer_match[] = { + { .compatible = "starfive,jh7110-timer", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, jh7110_timer_match); + +static struct platform_driver jh7110_timer_driver = { + .probe = jh7110_timer_probe, + .driver = { + .name = "jh7110-timer", + .of_match_table = jh7110_timer_match, + }, +}; +module_platform_driver(jh7110_timer_driver); + +MODULE_AUTHOR("Xingyu Wu "); +MODULE_DESCRIPTION("StarFive JH7110 timer driver"); +MODULE_LICENSE("GPL");