diff options
Diffstat (limited to 'drivers/clocksource/ingenic-timer.c')
-rw-r--r-- | drivers/clocksource/ingenic-timer.c | 423 |
1 files changed, 423 insertions, 0 deletions
diff --git a/drivers/clocksource/ingenic-timer.c b/drivers/clocksource/ingenic-timer.c new file mode 100644 index 000000000..905fd6b16 --- /dev/null +++ b/drivers/clocksource/ingenic-timer.c @@ -0,0 +1,423 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Ingenic SoCs TCU IRQ driver + * Copyright (C) 2019 Paul Cercueil <paul@crapouillou.net> + * Copyright (C) 2020 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/interrupt.h> +#include <linux/mfd/ingenic-tcu.h> +#include <linux/mfd/syscon.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/overflow.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/sched_clock.h> + +#include <dt-bindings/clock/ingenic,tcu.h> + +static DEFINE_PER_CPU(call_single_data_t, ingenic_cevt_csd); + +struct ingenic_soc_info { + unsigned int num_channels; +}; + +struct ingenic_tcu_timer { + unsigned int cpu; + unsigned int channel; + struct clock_event_device cevt; + struct clk *clk; + char name[8]; +}; + +struct ingenic_tcu { + struct regmap *map; + struct device_node *np; + struct clk *cs_clk; + unsigned int cs_channel; + struct clocksource cs; + unsigned long pwm_channels_mask; + struct ingenic_tcu_timer timers[]; +}; + +static struct ingenic_tcu *ingenic_tcu; + +static u64 notrace ingenic_tcu_timer_read(void) +{ + struct ingenic_tcu *tcu = ingenic_tcu; + unsigned int count; + + regmap_read(tcu->map, TCU_REG_TCNTc(tcu->cs_channel), &count); + + return count; +} + +static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource *cs) +{ + return ingenic_tcu_timer_read(); +} + +static inline struct ingenic_tcu * +to_ingenic_tcu(struct ingenic_tcu_timer *timer) +{ + return container_of(timer, struct ingenic_tcu, timers[timer->cpu]); +} + +static inline struct ingenic_tcu_timer * +to_ingenic_tcu_timer(struct clock_event_device *evt) +{ + return container_of(evt, struct ingenic_tcu_timer, cevt); +} + +static int ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device *evt) +{ + struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt); + struct ingenic_tcu *tcu = to_ingenic_tcu(timer); + + regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel)); + + return 0; +} + +static int ingenic_tcu_cevt_set_next(unsigned long next, + struct clock_event_device *evt) +{ + struct ingenic_tcu_timer *timer = to_ingenic_tcu_timer(evt); + struct ingenic_tcu *tcu = to_ingenic_tcu(timer); + + if (next > 0xffff) + return -EINVAL; + + regmap_write(tcu->map, TCU_REG_TDFRc(timer->channel), next); + regmap_write(tcu->map, TCU_REG_TCNTc(timer->channel), 0); + regmap_write(tcu->map, TCU_REG_TESR, BIT(timer->channel)); + + return 0; +} + +static void ingenic_per_cpu_event_handler(void *info) +{ + struct clock_event_device *cevt = (struct clock_event_device *) info; + + cevt->event_handler(cevt); +} + +static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id) +{ + struct ingenic_tcu_timer *timer = dev_id; + struct ingenic_tcu *tcu = to_ingenic_tcu(timer); + call_single_data_t *csd; + + regmap_write(tcu->map, TCU_REG_TECR, BIT(timer->channel)); + + if (timer->cevt.event_handler) { + csd = &per_cpu(ingenic_cevt_csd, timer->cpu); + csd->info = (void *) &timer->cevt; + csd->func = ingenic_per_cpu_event_handler; + smp_call_function_single_async(timer->cpu, csd); + } + + return IRQ_HANDLED; +} + +static struct clk *ingenic_tcu_get_clock(struct device_node *np, int id) +{ + struct of_phandle_args args; + + args.np = np; + args.args_count = 1; + args.args[0] = id; + + return of_clk_get_from_provider(&args); +} + +static int ingenic_tcu_setup_cevt(unsigned int cpu) +{ + struct ingenic_tcu *tcu = ingenic_tcu; + struct ingenic_tcu_timer *timer = &tcu->timers[cpu]; + unsigned int timer_virq; + struct irq_domain *domain; + unsigned long rate; + int err; + + timer->clk = ingenic_tcu_get_clock(tcu->np, timer->channel); + if (IS_ERR(timer->clk)) + return PTR_ERR(timer->clk); + + err = clk_prepare_enable(timer->clk); + if (err) + goto err_clk_put; + + rate = clk_get_rate(timer->clk); + if (!rate) { + err = -EINVAL; + goto err_clk_disable; + } + + domain = irq_find_host(tcu->np); + if (!domain) { + err = -ENODEV; + goto err_clk_disable; + } + + timer_virq = irq_create_mapping(domain, timer->channel); + if (!timer_virq) { + err = -EINVAL; + goto err_clk_disable; + } + + snprintf(timer->name, sizeof(timer->name), "TCU%u", timer->channel); + + err = request_irq(timer_virq, ingenic_tcu_cevt_cb, IRQF_TIMER, + timer->name, timer); + if (err) + goto err_irq_dispose_mapping; + + timer->cpu = smp_processor_id(); + timer->cevt.cpumask = cpumask_of(smp_processor_id()); + timer->cevt.features = CLOCK_EVT_FEAT_ONESHOT; + timer->cevt.name = timer->name; + timer->cevt.rating = 200; + timer->cevt.set_state_shutdown = ingenic_tcu_cevt_set_state_shutdown; + timer->cevt.set_next_event = ingenic_tcu_cevt_set_next; + + clockevents_config_and_register(&timer->cevt, rate, 10, 0xffff); + + return 0; + +err_irq_dispose_mapping: + irq_dispose_mapping(timer_virq); +err_clk_disable: + clk_disable_unprepare(timer->clk); +err_clk_put: + clk_put(timer->clk); + return err; +} + +static int __init ingenic_tcu_clocksource_init(struct device_node *np, + struct ingenic_tcu *tcu) +{ + unsigned int channel = tcu->cs_channel; + struct clocksource *cs = &tcu->cs; + unsigned long rate; + int err; + + tcu->cs_clk = ingenic_tcu_get_clock(np, channel); + if (IS_ERR(tcu->cs_clk)) + return PTR_ERR(tcu->cs_clk); + + err = clk_prepare_enable(tcu->cs_clk); + if (err) + goto err_clk_put; + + rate = clk_get_rate(tcu->cs_clk); + if (!rate) { + err = -EINVAL; + goto err_clk_disable; + } + + /* Reset channel */ + regmap_update_bits(tcu->map, TCU_REG_TCSRc(channel), + 0xffff & ~TCU_TCSR_RESERVED_BITS, 0); + + /* Reset counter */ + regmap_write(tcu->map, TCU_REG_TDFRc(channel), 0xffff); + regmap_write(tcu->map, TCU_REG_TCNTc(channel), 0); + + /* Enable channel */ + regmap_write(tcu->map, TCU_REG_TESR, BIT(channel)); + + cs->name = "ingenic-timer"; + cs->rating = 200; + cs->flags = CLOCK_SOURCE_IS_CONTINUOUS; + cs->mask = CLOCKSOURCE_MASK(16); + cs->read = ingenic_tcu_timer_cs_read; + + err = clocksource_register_hz(cs, rate); + if (err) + goto err_clk_disable; + + return 0; + +err_clk_disable: + clk_disable_unprepare(tcu->cs_clk); +err_clk_put: + clk_put(tcu->cs_clk); + return err; +} + +static const struct ingenic_soc_info jz4740_soc_info = { + .num_channels = 8, +}; + +static const struct ingenic_soc_info jz4725b_soc_info = { + .num_channels = 6, +}; + +static const struct of_device_id ingenic_tcu_of_match[] = { + { .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, }, + { .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, }, + { .compatible = "ingenic,jz4770-tcu", .data = &jz4740_soc_info, }, + { .compatible = "ingenic,x1000-tcu", .data = &jz4740_soc_info, }, + { /* sentinel */ } +}; + +static int __init ingenic_tcu_init(struct device_node *np) +{ + const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np); + const struct ingenic_soc_info *soc_info = id->data; + struct ingenic_tcu_timer *timer; + struct ingenic_tcu *tcu; + struct regmap *map; + unsigned int cpu; + int ret, last_bit = -1; + long rate; + + of_node_clear_flag(np, OF_POPULATED); + + map = device_node_to_regmap(np); + if (IS_ERR(map)) + return PTR_ERR(map); + + tcu = kzalloc(struct_size(tcu, timers, num_possible_cpus()), + GFP_KERNEL); + if (!tcu) + return -ENOMEM; + + /* + * Enable all TCU channels for PWM use by default except channels 0/1, + * and channel 2 if target CPU is JZ4780/X2000 and SMP is selected. + */ + tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1, + num_possible_cpus() + 1); + of_property_read_u32(np, "ingenic,pwm-channels-mask", + (u32 *)&tcu->pwm_channels_mask); + + /* Verify that we have at least num_possible_cpus() + 1 free channels */ + if (hweight8(tcu->pwm_channels_mask) > + soc_info->num_channels - num_possible_cpus() + 1) { + pr_crit("%s: Invalid PWM channel mask: 0x%02lx\n", __func__, + tcu->pwm_channels_mask); + ret = -EINVAL; + goto err_free_ingenic_tcu; + } + + tcu->map = map; + tcu->np = np; + ingenic_tcu = tcu; + + for (cpu = 0; cpu < num_possible_cpus(); cpu++) { + timer = &tcu->timers[cpu]; + + timer->cpu = cpu; + timer->channel = find_next_zero_bit(&tcu->pwm_channels_mask, + soc_info->num_channels, + last_bit + 1); + last_bit = timer->channel; + } + + tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask, + soc_info->num_channels, + last_bit + 1); + + ret = ingenic_tcu_clocksource_init(np, tcu); + if (ret) { + pr_crit("%s: Unable to init clocksource: %d\n", __func__, ret); + goto err_free_ingenic_tcu; + } + + /* Setup clock events on each CPU core */ + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "Ingenic XBurst: online", + ingenic_tcu_setup_cevt, NULL); + if (ret < 0) { + pr_crit("%s: Unable to start CPU timers: %d\n", __func__, ret); + goto err_tcu_clocksource_cleanup; + } + + /* Register the sched_clock at the end as there's no way to undo it */ + rate = clk_get_rate(tcu->cs_clk); + sched_clock_register(ingenic_tcu_timer_read, 16, rate); + + return 0; + +err_tcu_clocksource_cleanup: + clocksource_unregister(&tcu->cs); + clk_disable_unprepare(tcu->cs_clk); + clk_put(tcu->cs_clk); +err_free_ingenic_tcu: + kfree(tcu); + return ret; +} + +TIMER_OF_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu", ingenic_tcu_init); +TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", ingenic_tcu_init); +TIMER_OF_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu", ingenic_tcu_init); +TIMER_OF_DECLARE(x1000_tcu_intc, "ingenic,x1000-tcu", ingenic_tcu_init); + +static int __init ingenic_tcu_probe(struct platform_device *pdev) +{ + platform_set_drvdata(pdev, ingenic_tcu); + + return 0; +} + +static int __maybe_unused ingenic_tcu_suspend(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + unsigned int cpu; + + clk_disable(tcu->cs_clk); + + for (cpu = 0; cpu < num_online_cpus(); cpu++) + clk_disable(tcu->timers[cpu].clk); + + return 0; +} + +static int __maybe_unused ingenic_tcu_resume(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + unsigned int cpu; + int ret; + + for (cpu = 0; cpu < num_online_cpus(); cpu++) { + ret = clk_enable(tcu->timers[cpu].clk); + if (ret) + goto err_timer_clk_disable; + } + + ret = clk_enable(tcu->cs_clk); + if (ret) + goto err_timer_clk_disable; + + return 0; + +err_timer_clk_disable: + for (; cpu > 0; cpu--) + clk_disable(tcu->timers[cpu - 1].clk); + return ret; +} + +static const struct dev_pm_ops __maybe_unused ingenic_tcu_pm_ops = { + /* _noirq: We want the TCU clocks to be gated last / ungated first */ + .suspend_noirq = ingenic_tcu_suspend, + .resume_noirq = ingenic_tcu_resume, +}; + +static struct platform_driver ingenic_tcu_driver = { + .driver = { + .name = "ingenic-tcu-timer", +#ifdef CONFIG_PM_SLEEP + .pm = &ingenic_tcu_pm_ops, +#endif + .of_match_table = ingenic_tcu_of_match, + }, +}; +builtin_platform_driver_probe(ingenic_tcu_driver, ingenic_tcu_probe); |