From 56558f38188eded37eb4c0fe099ee5e3fbb364b4 Mon Sep 17 00:00:00 2001 From: Xingyu Wu Date: Tue, 1 Nov 2022 21:45:06 +0800 Subject: [PATCH] clocksource: Add StarFive timer driver Add timer driver for the StarFive JH7110 SoC. Signed-off-by: Xingyu Wu --- drivers/clocksource/Kconfig | 12 ++ drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-starfive.c | 390 +++++++++++++++++++++++++++++++++++ drivers/clocksource/timer-starfive.h | 96 +++++++++ 4 files changed, 499 insertions(+) create mode 100644 drivers/clocksource/timer-starfive.c create mode 100644 drivers/clocksource/timer-starfive.h diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 4469e7f..6341128 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -630,6 +630,18 @@ config RISCV_TIMER is accessed via both the SBI and the rdcycle instruction. This is required for all RISC-V systems. +config STARFIVE_TIMER + bool "Timer for the STARFIVE SoCs" + depends on ARCH_STARFIVE || COMPILE_TEST + select TIMER_OF + select CLKSRC_MMIO + default ARCH_STARFIVE + help + This enables the timer for StarFive SoCs. On RISC-V platform, + the system has started RISCV_TIMER. But you can also use this timer + to do a lot more on StarFive SoCs. This timer can provide high + precision and four channels to use in JH7110 SoC. + config CLINT_TIMER bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST depends on GENERIC_SCHED_CLOCK && RISCV diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 64ab547..276695d 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -80,6 +80,7 @@ obj-$(CONFIG_INGENIC_TIMER) += ingenic-timer.o obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o obj-$(CONFIG_X86_NUMACHIP) += numachip.o obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o +obj-$(CONFIG_STARFIVE_TIMER) += timer-starfive.o obj-$(CONFIG_CLINT_TIMER) += timer-clint.o obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o diff --git a/drivers/clocksource/timer-starfive.c b/drivers/clocksource/timer-starfive.c new file mode 100644 index 0000000..5316394 --- /dev/null +++ b/drivers/clocksource/timer-starfive.c @@ -0,0 +1,390 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Starfive Timer driver + * + * Copyright (C) 2022 StarFive Technology Co., Ltd. + * + * Author: + * Xingyu Wu + * Samin Guo + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "timer-starfive.h" + +static const struct starfive_timer_chan_base starfive_timer_jh7110_base = { + .ctrl = STARFIVE_TIMER_JH7110_CTL, + .load = STARFIVE_TIMER_JH7110_LOAD, + .enable = STARFIVE_TIMER_JH7110_ENABLE, + .reload = STARFIVE_TIMER_JH7110_RELOAD, + .value = STARFIVE_TIMER_JH7110_VALUE, + .intclr = STARFIVE_TIMER_JH7110_INT_CLR, + .intmask = STARFIVE_TIMER_JH7110_INT_MASK, + .channel_num = STARFIVE_TIMER_CH_4, + .channel_base = {STARFIVE_TIMER_CH_BASE(0), STARFIVE_TIMER_CH_BASE(1), + STARFIVE_TIMER_CH_BASE(2), STARFIVE_TIMER_CH_BASE(3)}, +}; + +static inline struct starfive_clkevt *to_starfive_clkevt(struct clock_event_device *evt) +{ + return container_of(evt, struct starfive_clkevt, evt); +} + +/* 0:continuous-run mode, 1:single-run mode */ +static inline void starfive_timer_set_mod(struct starfive_clkevt *clkevt, int mod) +{ + writel(mod, clkevt->ctrl); +} + +/* Interrupt Mask Register, 0:Unmask, 1:Mask */ +static inline void starfive_timer_int_enable(struct starfive_clkevt *clkevt) +{ + writel(STARFIVE_TIMER_INTMASK_DIS, clkevt->intmask); +} + +static inline void starfive_timer_int_disable(struct starfive_clkevt *clkevt) +{ + writel(STARFIVE_TIMER_INTMASK_ENA, clkevt->intmask); +} + +/* + * BIT(0): Read value represent channel intr 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 starfive_timer_int_clear(struct starfive_clkevt *clkevt) +{ + u32 value; + int ret; + + /* waiting interrupt can be to clearing */ + ret = readl_poll_timeout_atomic(clkevt->intclr, value, + !(value & STARFIVE_TIMER_JH7110_INT_CLR_AVA_MASK), + STARFIVE_DELAY_US, STARFIVE_TIMEOUT_US); + if (!ret) + writel(0x1, clkevt->intclr); + + return ret; +} + +/* + * The initial value to be loaded into the + * counter and is also used as the reload value. + * val = clock rate --> 1s + */ +static inline void starfive_timer_set_load(struct starfive_clkevt *clkevt, u32 val) +{ + writel(val, clkevt->load); +} + +static inline u32 starfive_timer_get_val(struct starfive_clkevt *clkevt) +{ + return readl(clkevt->value); +} + +/* + * Write RELOAD register to reload preset value to counter. + * (Write 0 and write 1 are both ok) + */ +static inline void starfive_timer_set_reload(struct starfive_clkevt *clkevt) +{ + writel(0, clkevt->reload); +} + +static inline void starfive_timer_enable(struct starfive_clkevt *clkevt) +{ + writel(STARFIVE_TIMER_ENA, clkevt->enable); +} + +static inline void starfive_timer_disable(struct starfive_clkevt *clkevt) +{ + writel(STARFIVE_TIMER_DIS, clkevt->enable); +} + +static int starfive_timer_int_init_enable(struct starfive_clkevt *clkevt) +{ + int ret; + + starfive_timer_int_disable(clkevt); + ret = starfive_timer_int_clear(clkevt); + if (ret) + return ret; + + starfive_timer_int_enable(clkevt); + starfive_timer_enable(clkevt); + + return 0; +} + +static int starfive_timer_shutdown(struct clock_event_device *evt) +{ + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + starfive_timer_disable(clkevt); + return starfive_timer_int_clear(clkevt); +} + +static void starfive_timer_suspend(struct clock_event_device *evt) +{ + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + clkevt->reload_val = starfive_timer_get_val(clkevt); + starfive_timer_shutdown(evt); +} + +static void starfive_timer_resume(struct clock_event_device *evt) +{ + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + starfive_timer_set_load(clkevt, clkevt->reload_val); + starfive_timer_set_reload(clkevt); + starfive_timer_int_enable(clkevt); + starfive_timer_enable(clkevt); +} + +static int starfive_timer_tick_resume(struct clock_event_device *evt) +{ + starfive_timer_resume(evt); + + return 0; +} + +static int starfive_clocksource_init(struct starfive_clkevt *clkevt) +{ + int ret; + + starfive_timer_set_mod(clkevt, STARFIVE_TIMER_MOD_CONTIN); + starfive_timer_set_load(clkevt, STARFIVE_TIMER_MAX_TICKS); + ret = starfive_timer_int_init_enable(clkevt); + if (ret) + return ret; + + return clocksource_mmio_init(clkevt->value, clkevt->name, clkevt->rate, + STARFIVE_CLOCK_SOURCE_RATING, STARFIVE_VALID_BITS, + clocksource_mmio_readl_down); +} + +/* IRQ handler for the timer */ +static irqreturn_t starfive_timer_interrupt(int irq, void *priv) +{ + struct clock_event_device *evt = (struct clock_event_device *)priv; + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + if (starfive_timer_int_clear(clkevt)) + return IRQ_NONE; + + if (evt->event_handler) + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static int starfive_timer_set_periodic(struct clock_event_device *evt) +{ + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + starfive_timer_disable(clkevt); + starfive_timer_set_mod(clkevt, STARFIVE_TIMER_MOD_CONTIN); + starfive_timer_set_load(clkevt, clkevt->periodic); + + return starfive_timer_int_init_enable(clkevt); +} + +static int starfive_timer_set_oneshot(struct clock_event_device *evt) +{ + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + starfive_timer_disable(clkevt); + starfive_timer_set_mod(clkevt, STARFIVE_TIMER_MOD_SINGLE); + starfive_timer_set_load(clkevt, STARFIVE_TIMER_MAX_TICKS); + + return starfive_timer_int_init_enable(clkevt); +} + +static int starfive_timer_set_next_event(unsigned long next, + struct clock_event_device *evt) +{ + struct starfive_clkevt *clkevt = to_starfive_clkevt(evt); + + starfive_timer_disable(clkevt); + starfive_timer_set_mod(clkevt, STARFIVE_TIMER_MOD_SINGLE); + starfive_timer_set_load(clkevt, next); + starfive_timer_enable(clkevt); + + return 0; +} + +static void starfive_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 = starfive_timer_shutdown; + evt->set_state_periodic = starfive_timer_set_periodic; + evt->set_state_oneshot = starfive_timer_set_oneshot; + evt->set_state_oneshot_stopped = starfive_timer_shutdown; + evt->tick_resume = starfive_timer_tick_resume; + evt->set_next_event = starfive_timer_set_next_event; + evt->suspend = starfive_timer_suspend; + evt->resume = starfive_timer_resume; + evt->rating = STARFIVE_CLOCKEVENT_RATING; +} + +static void starfive_clockevents_register(struct starfive_clkevt *clkevt) +{ + clkevt->rate = clk_get_rate(clkevt->clk); + clkevt->periodic = DIV_ROUND_CLOSEST(clkevt->rate, HZ); + + starfive_set_clockevent(&clkevt->evt); + clkevt->evt.name = clkevt->name; + clkevt->evt.irq = clkevt->irq; + clkevt->evt.cpumask = cpu_possible_mask; + + clockevents_config_and_register(&clkevt->evt, clkevt->rate, + STARFIVE_TIMER_MIN_TICKS, STARFIVE_TIMER_MAX_TICKS); +} + +static void __init starfive_clkevt_base_init(const struct starfive_timer_chan_base *timer, + struct starfive_clkevt *clkevt, + void __iomem *base, int ch) +{ + void __iomem *channel_base; + + channel_base = base + timer->channel_base[ch]; + clkevt->base = channel_base; + clkevt->ctrl = channel_base + timer->ctrl; + clkevt->load = channel_base + timer->load; + clkevt->enable = channel_base + timer->enable; + clkevt->reload = channel_base + timer->reload; + clkevt->value = channel_base + timer->value; + clkevt->intclr = channel_base + timer->intclr; + clkevt->intmask = channel_base + timer->intmask; +} + +static int __init starfive_timer_probe(struct platform_device *pdev) +{ + const struct starfive_timer_chan_base *timer_base = of_device_get_match_data(&pdev->dev); + char name[10]; + struct starfive_timer_priv *priv; + struct starfive_clkevt *clkevt; + struct clk *pclk; + struct reset_control *rst; + int ch; + int ret; + + priv = devm_kzalloc(&pdev->dev, struct_size(priv, clkevt, timer_base->channel_num), + GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return dev_err_probe(&pdev->dev, PTR_ERR(priv->base), + "failed to map registers\n"); + + rst = devm_reset_control_get_exclusive(&pdev->dev, "apb"); + if (IS_ERR(rst)) + return dev_err_probe(&pdev->dev, PTR_ERR(rst), "failed to get apb reset\n"); + + pclk = devm_clk_get_enabled(&pdev->dev, "apb"); + if (IS_ERR(pclk)) + return dev_err_probe(&pdev->dev, PTR_ERR(pclk), + "failed to get & enable apb clock\n"); + + ret = reset_control_deassert(rst); + if (ret) + goto err; + + priv->dev = &pdev->dev; + platform_set_drvdata(pdev, priv); + + for (ch = 0; ch < timer_base->channel_num; ch++) { + clkevt = &priv->clkevt[ch]; + snprintf(name, sizeof(name), "ch%d", ch); + + starfive_clkevt_base_init(timer_base, clkevt, priv->base, ch); + /* Ensure timers are disabled */ + starfive_timer_disable(clkevt); + + rst = devm_reset_control_get_exclusive(&pdev->dev, name); + if (IS_ERR(rst)) { + ret = PTR_ERR(rst); + goto err; + } + + clkevt->clk = devm_clk_get_enabled(&pdev->dev, name); + if (IS_ERR(clkevt->clk)) { + ret = PTR_ERR(clkevt->clk); + goto err; + } + + ret = reset_control_deassert(rst); + if (ret) + goto ch_err; + + clkevt->irq = platform_get_irq(pdev, ch); + if (clkevt->irq < 0) { + ret = clkevt->irq; + goto ch_err; + } + + snprintf(clkevt->name, sizeof(clkevt->name), "%s.ch%d", pdev->name, ch); + starfive_clockevents_register(clkevt); + + ret = devm_request_irq(&pdev->dev, clkevt->irq, starfive_timer_interrupt, + IRQF_TIMER | IRQF_IRQPOLL, + clkevt->name, &clkevt->evt); + if (ret) + goto ch_err; + + ret = starfive_clocksource_init(clkevt); + if (ret) + goto ch_err; + } + + return 0; + +ch_err: + /* Only unregister the failed channel and the rest timer channels continue to work. */ + clk_disable_unprepare(clkevt->clk); +err: + /* If no other channel successfully registers, pclk should be disabled. */ + if (!ch) + clk_disable_unprepare(pclk); + + return ret; +} + +static const struct of_device_id starfive_timer_match[] = { + { .compatible = "starfive,jh7110-timer", .data = &starfive_timer_jh7110_base }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, starfive_timer_match); + +static struct platform_driver starfive_timer_driver = { + .probe = starfive_timer_probe, + .driver = { + .name = "starfive-timer", + .of_match_table = starfive_timer_match, + }, +}; +module_platform_driver(starfive_timer_driver); + +MODULE_AUTHOR("Xingyu Wu "); +MODULE_DESCRIPTION("StarFive timer driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/clocksource/timer-starfive.h b/drivers/clocksource/timer-starfive.h new file mode 100644 index 0000000..62eb630 --- /dev/null +++ b/drivers/clocksource/timer-starfive.h @@ -0,0 +1,96 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022 StarFive Technology Co., Ltd. + */ + +#ifndef __STARFIVE_TIMER_H__ +#define __STARFIVE_TIMER_H__ + +/* Bias: Ch0-0x0, Ch1-0x40, Ch2-0x80, and so on. */ +#define STARFIVE_TIMER_CH_LEN 0x40 +#define STARFIVE_TIMER_CH_BASE(x) ((STARFIVE_TIMER_CH_##x) * STARFIVE_TIMER_CH_LEN) + +#define STARFIVE_CLOCK_SOURCE_RATING 200 +#define STARFIVE_VALID_BITS 32 +#define STARFIVE_DELAY_US 0 +#define STARFIVE_TIMEOUT_US 10000 +#define STARFIVE_CLOCKEVENT_RATING 300 +#define STARFIVE_TIMER_MAX_TICKS 0xffffffff +#define STARFIVE_TIMER_MIN_TICKS 0xf + +#define STARFIVE_TIMER_JH7110_INT_STATUS 0x00 /* RO[0:4]: Interrupt Status for channel0~4 */ +#define STARFIVE_TIMER_JH7110_CTL 0x04 /* RW[0]: 0-continuous run, 1-single run */ +#define STARFIVE_TIMER_JH7110_LOAD 0x08 /* RW: load value to counter */ +#define STARFIVE_TIMER_JH7110_ENABLE 0x10 /* RW[0]: timer enable register */ +#define STARFIVE_TIMER_JH7110_RELOAD 0x14 /* RW: write 1 or 0 both reload counter */ +#define STARFIVE_TIMER_JH7110_VALUE 0x18 /* RO: timer value register */ +#define STARFIVE_TIMER_JH7110_INT_CLR 0x20 /* RW: timer interrupt clear register */ +#define STARFIVE_TIMER_JH7110_INT_MASK 0x24 /* RW[0]: timer interrupt mask register */ +#define STARFIVE_TIMER_JH7110_INT_CLR_AVA_MASK BIT(1) + +enum STARFIVE_TIMER_CH { + STARFIVE_TIMER_CH_0 = 0, + STARFIVE_TIMER_CH_1, + STARFIVE_TIMER_CH_2, + STARFIVE_TIMER_CH_3, + STARFIVE_TIMER_CH_4, + STARFIVE_TIMER_CH_5, + STARFIVE_TIMER_CH_6, + STARFIVE_TIMER_CH_7, + STARFIVE_TIMER_CH_MAX +}; + +enum STARFIVE_TIMER_INTMASK { + STARFIVE_TIMER_INTMASK_DIS = 0, + STARFIVE_TIMER_INTMASK_ENA = 1 +}; + +enum STARFIVE_TIMER_MOD { + STARFIVE_TIMER_MOD_CONTIN = 0, + STARFIVE_TIMER_MOD_SINGLE = 1 +}; + +enum STARFIVE_TIMER_CTL_EN { + STARFIVE_TIMER_DIS = 0, + STARFIVE_TIMER_ENA = 1 +}; + +struct starfive_timer_chan_base { + /* Resgister */ + unsigned int ctrl; + unsigned int load; + unsigned int enable; + unsigned int reload; + unsigned int value; + unsigned int intclr; + unsigned int intmask; + + unsigned int channel_num; /* timer channel numbers */ + unsigned int channel_base[]; +}; + +struct starfive_clkevt { + struct clock_event_device evt; + struct clk *clk; + char name[20]; + int irq; + u32 periodic; + u32 rate; + u32 reload_val; + void __iomem *base; + void __iomem *ctrl; + void __iomem *load; + void __iomem *enable; + void __iomem *reload; + void __iomem *value; + void __iomem *intclr; + void __iomem *intmask; +}; + +struct starfive_timer_priv { + struct device *dev; + void __iomem *base; + struct starfive_clkevt clkevt[]; +}; + +#endif /* __STARFIVE_TIMER_H__ */ -- 2.7.4