| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Copyright (C) 2010 Google, Inc. |
| * |
| * Author: |
| * Colin Cross <ccross@google.com> |
| */ |
| |
| #include <linux/clk.h> |
| #include <linux/clockchips.h> |
| #include <linux/cpu.h> |
| #include <linux/cpumask.h> |
| #include <linux/delay.h> |
| #include <linux/err.h> |
| #include <linux/interrupt.h> |
| #include <linux/of_address.h> |
| #include <linux/of_irq.h> |
| #include <linux/percpu.h> |
| #include <linux/sched_clock.h> |
| #include <linux/time.h> |
| |
| #include "timer-of.h" |
| |
| #ifdef CONFIG_ARM |
| #include <asm/mach/time.h> |
| #endif |
| |
| #define RTC_SECONDS 0x08 |
| #define RTC_SHADOW_SECONDS 0x0c |
| #define RTC_MILLISECONDS 0x10 |
| |
| #define TIMERUS_CNTR_1US 0x10 |
| #define TIMERUS_USEC_CFG 0x14 |
| #define TIMERUS_CNTR_FREEZE 0x4c |
| |
| #define TIMER_PTV 0x0 |
| #define TIMER_PTV_EN BIT(31) |
| #define TIMER_PTV_PER BIT(30) |
| #define TIMER_PCR 0x4 |
| #define TIMER_PCR_INTR_CLR BIT(30) |
| |
| #ifdef CONFIG_ARM |
| #define TIMER_CPU0 0x50 /* TIMER3 */ |
| #else |
| #define TIMER_CPU0 0x90 /* TIMER10 */ |
| #define TIMER10_IRQ_IDX 10 |
| #define IRQ_IDX_FOR_CPU(cpu) (TIMER10_IRQ_IDX + cpu) |
| #endif |
| #define TIMER_BASE_FOR_CPU(cpu) (TIMER_CPU0 + (cpu) * 8) |
| |
| static u32 usec_config; |
| static void __iomem *timer_reg_base; |
| #ifdef CONFIG_ARM |
| static struct delay_timer tegra_delay_timer; |
| #endif |
| |
| static int tegra_timer_set_next_event(unsigned long cycles, |
| struct clock_event_device *evt) |
| { |
| void __iomem *reg_base = timer_of_base(to_timer_of(evt)); |
| |
| writel(TIMER_PTV_EN | |
| ((cycles > 1) ? (cycles - 1) : 0), /* n+1 scheme */ |
| reg_base + TIMER_PTV); |
| |
| return 0; |
| } |
| |
| static int tegra_timer_shutdown(struct clock_event_device *evt) |
| { |
| void __iomem *reg_base = timer_of_base(to_timer_of(evt)); |
| |
| writel(0, reg_base + TIMER_PTV); |
| |
| return 0; |
| } |
| |
| static int tegra_timer_set_periodic(struct clock_event_device *evt) |
| { |
| void __iomem *reg_base = timer_of_base(to_timer_of(evt)); |
| |
| writel(TIMER_PTV_EN | TIMER_PTV_PER | |
| ((timer_of_rate(to_timer_of(evt)) / HZ) - 1), |
| reg_base + TIMER_PTV); |
| |
| return 0; |
| } |
| |
| static irqreturn_t tegra_timer_isr(int irq, void *dev_id) |
| { |
| struct clock_event_device *evt = (struct clock_event_device *)dev_id; |
| void __iomem *reg_base = timer_of_base(to_timer_of(evt)); |
| |
| writel(TIMER_PCR_INTR_CLR, reg_base + TIMER_PCR); |
| evt->event_handler(evt); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void tegra_timer_suspend(struct clock_event_device *evt) |
| { |
| void __iomem *reg_base = timer_of_base(to_timer_of(evt)); |
| |
| writel(TIMER_PCR_INTR_CLR, reg_base + TIMER_PCR); |
| } |
| |
| static void tegra_timer_resume(struct clock_event_device *evt) |
| { |
| writel(usec_config, timer_reg_base + TIMERUS_USEC_CFG); |
| } |
| |
| #ifdef CONFIG_ARM64 |
| static DEFINE_PER_CPU(struct timer_of, tegra_to) = { |
| .flags = TIMER_OF_CLOCK | TIMER_OF_BASE, |
| |
| .clkevt = { |
| .name = "tegra_timer", |
| .rating = 460, |
| .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, |
| .set_next_event = tegra_timer_set_next_event, |
| .set_state_shutdown = tegra_timer_shutdown, |
| .set_state_periodic = tegra_timer_set_periodic, |
| .set_state_oneshot = tegra_timer_shutdown, |
| .tick_resume = tegra_timer_shutdown, |
| .suspend = tegra_timer_suspend, |
| .resume = tegra_timer_resume, |
| }, |
| }; |
| |
| static int tegra_timer_setup(unsigned int cpu) |
| { |
| struct timer_of *to = per_cpu_ptr(&tegra_to, cpu); |
| |
| irq_force_affinity(to->clkevt.irq, cpumask_of(cpu)); |
| enable_irq(to->clkevt.irq); |
| |
| clockevents_config_and_register(&to->clkevt, timer_of_rate(to), |
| 1, /* min */ |
| 0x1fffffff); /* 29 bits */ |
| |
| return 0; |
| } |
| |
| static int tegra_timer_stop(unsigned int cpu) |
| { |
| struct timer_of *to = per_cpu_ptr(&tegra_to, cpu); |
| |
| to->clkevt.set_state_shutdown(&to->clkevt); |
| disable_irq_nosync(to->clkevt.irq); |
| |
| return 0; |
| } |
| #else /* CONFIG_ARM */ |
| static struct timer_of tegra_to = { |
| .flags = TIMER_OF_CLOCK | TIMER_OF_BASE | TIMER_OF_IRQ, |
| |
| .clkevt = { |
| .name = "tegra_timer", |
| .rating = 300, |
| .features = CLOCK_EVT_FEAT_ONESHOT | |
| CLOCK_EVT_FEAT_PERIODIC | |
| CLOCK_EVT_FEAT_DYNIRQ, |
| .set_next_event = tegra_timer_set_next_event, |
| .set_state_shutdown = tegra_timer_shutdown, |
| .set_state_periodic = tegra_timer_set_periodic, |
| .set_state_oneshot = tegra_timer_shutdown, |
| .tick_resume = tegra_timer_shutdown, |
| .suspend = tegra_timer_suspend, |
| .resume = tegra_timer_resume, |
| .cpumask = cpu_possible_mask, |
| }, |
| |
| .of_irq = { |
| .index = 2, |
| .flags = IRQF_TIMER | IRQF_TRIGGER_HIGH, |
| .handler = tegra_timer_isr, |
| }, |
| }; |
| |
| static u64 notrace tegra_read_sched_clock(void) |
| { |
| return readl(timer_reg_base + TIMERUS_CNTR_1US); |
| } |
| |
| static unsigned long tegra_delay_timer_read_counter_long(void) |
| { |
| return readl(timer_reg_base + TIMERUS_CNTR_1US); |
| } |
| |
| static struct timer_of suspend_rtc_to = { |
| .flags = TIMER_OF_BASE | TIMER_OF_CLOCK, |
| }; |
| |
| /* |
| * tegra_rtc_read - Reads the Tegra RTC registers |
| * Care must be taken that this funciton is not called while the |
| * tegra_rtc driver could be executing to avoid race conditions |
| * on the RTC shadow register |
| */ |
| static u64 tegra_rtc_read_ms(struct clocksource *cs) |
| { |
| u32 ms = readl(timer_of_base(&suspend_rtc_to) + RTC_MILLISECONDS); |
| u32 s = readl(timer_of_base(&suspend_rtc_to) + RTC_SHADOW_SECONDS); |
| return (u64)s * MSEC_PER_SEC + ms; |
| } |
| |
| static struct clocksource suspend_rtc_clocksource = { |
| .name = "tegra_suspend_timer", |
| .rating = 200, |
| .read = tegra_rtc_read_ms, |
| .mask = CLOCKSOURCE_MASK(32), |
| .flags = CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP, |
| }; |
| #endif |
| |
| static int tegra_timer_common_init(struct device_node *np, struct timer_of *to) |
| { |
| int ret = 0; |
| |
| ret = timer_of_init(np, to); |
| if (ret < 0) |
| goto out; |
| |
| timer_reg_base = timer_of_base(to); |
| |
| /* |
| * Configure microsecond timers to have 1MHz clock |
| * Config register is 0xqqww, where qq is "dividend", ww is "divisor" |
| * Uses n+1 scheme |
| */ |
| switch (timer_of_rate(to)) { |
| case 12000000: |
| usec_config = 0x000b; /* (11+1)/(0+1) */ |
| break; |
| case 12800000: |
| usec_config = 0x043f; /* (63+1)/(4+1) */ |
| break; |
| case 13000000: |
| usec_config = 0x000c; /* (12+1)/(0+1) */ |
| break; |
| case 16800000: |
| usec_config = 0x0453; /* (83+1)/(4+1) */ |
| break; |
| case 19200000: |
| usec_config = 0x045f; /* (95+1)/(4+1) */ |
| break; |
| case 26000000: |
| usec_config = 0x0019; /* (25+1)/(0+1) */ |
| break; |
| case 38400000: |
| usec_config = 0x04bf; /* (191+1)/(4+1) */ |
| break; |
| case 48000000: |
| usec_config = 0x002f; /* (47+1)/(0+1) */ |
| break; |
| default: |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| writel(usec_config, timer_of_base(to) + TIMERUS_USEC_CFG); |
| |
| out: |
| return ret; |
| } |
| |
| #ifdef CONFIG_ARM64 |
| static int __init tegra_init_timer(struct device_node *np) |
| { |
| int cpu, ret = 0; |
| struct timer_of *to; |
| |
| to = this_cpu_ptr(&tegra_to); |
| ret = tegra_timer_common_init(np, to); |
| if (ret < 0) |
| goto out; |
| |
| for_each_possible_cpu(cpu) { |
| struct timer_of *cpu_to; |
| |
| cpu_to = per_cpu_ptr(&tegra_to, cpu); |
| cpu_to->of_base.base = timer_reg_base + TIMER_BASE_FOR_CPU(cpu); |
| cpu_to->of_clk.rate = timer_of_rate(to); |
| cpu_to->clkevt.cpumask = cpumask_of(cpu); |
| cpu_to->clkevt.irq = |
| irq_of_parse_and_map(np, IRQ_IDX_FOR_CPU(cpu)); |
| if (!cpu_to->clkevt.irq) { |
| pr_err("%s: can't map IRQ for CPU%d\n", |
| __func__, cpu); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| irq_set_status_flags(cpu_to->clkevt.irq, IRQ_NOAUTOEN); |
| ret = request_irq(cpu_to->clkevt.irq, tegra_timer_isr, |
| IRQF_TIMER | IRQF_NOBALANCING, |
| cpu_to->clkevt.name, &cpu_to->clkevt); |
| if (ret) { |
| pr_err("%s: cannot setup irq %d for CPU%d\n", |
| __func__, cpu_to->clkevt.irq, cpu); |
| ret = -EINVAL; |
| goto out_irq; |
| } |
| } |
| |
| cpuhp_setup_state(CPUHP_AP_TEGRA_TIMER_STARTING, |
| "AP_TEGRA_TIMER_STARTING", tegra_timer_setup, |
| tegra_timer_stop); |
| |
| return ret; |
| out_irq: |
| for_each_possible_cpu(cpu) { |
| struct timer_of *cpu_to; |
| |
| cpu_to = per_cpu_ptr(&tegra_to, cpu); |
| if (cpu_to->clkevt.irq) { |
| free_irq(cpu_to->clkevt.irq, &cpu_to->clkevt); |
| irq_dispose_mapping(cpu_to->clkevt.irq); |
| } |
| } |
| out: |
| timer_of_cleanup(to); |
| return ret; |
| } |
| #else /* CONFIG_ARM */ |
| static int __init tegra_init_timer(struct device_node *np) |
| { |
| int ret = 0; |
| |
| ret = tegra_timer_common_init(np, &tegra_to); |
| if (ret < 0) |
| goto out; |
| |
| tegra_to.of_base.base = timer_reg_base + TIMER_BASE_FOR_CPU(0); |
| tegra_to.of_clk.rate = 1000000; /* microsecond timer */ |
| |
| sched_clock_register(tegra_read_sched_clock, 32, |
| timer_of_rate(&tegra_to)); |
| ret = clocksource_mmio_init(timer_reg_base + TIMERUS_CNTR_1US, |
| "timer_us", timer_of_rate(&tegra_to), |
| 300, 32, clocksource_mmio_readl_up); |
| if (ret) { |
| pr_err("Failed to register clocksource\n"); |
| goto out; |
| } |
| |
| tegra_delay_timer.read_current_timer = |
| tegra_delay_timer_read_counter_long; |
| tegra_delay_timer.freq = timer_of_rate(&tegra_to); |
| register_current_timer_delay(&tegra_delay_timer); |
| |
| clockevents_config_and_register(&tegra_to.clkevt, |
| timer_of_rate(&tegra_to), |
| 0x1, |
| 0x1fffffff); |
| |
| return ret; |
| out: |
| timer_of_cleanup(&tegra_to); |
| |
| return ret; |
| } |
| |
| static int __init tegra20_init_rtc(struct device_node *np) |
| { |
| int ret; |
| |
| ret = timer_of_init(np, &suspend_rtc_to); |
| if (ret) |
| return ret; |
| |
| clocksource_register_hz(&suspend_rtc_clocksource, 1000); |
| |
| return 0; |
| } |
| TIMER_OF_DECLARE(tegra20_rtc, "nvidia,tegra20-rtc", tegra20_init_rtc); |
| #endif |
| TIMER_OF_DECLARE(tegra210_timer, "nvidia,tegra210-timer", tegra_init_timer); |
| TIMER_OF_DECLARE(tegra20_timer, "nvidia,tegra20-timer", tegra_init_timer); |