| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Mediatek SoCs General-Purpose Timer handling. |
| * |
| * Copyright (C) 2014 Matthias Brugger |
| * |
| * Matthias Brugger <matthias.bgg@gmail.com> |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/clockchips.h> |
| #include <linux/clocksource.h> |
| #include <linux/interrupt.h> |
| #include <linux/irqreturn.h> |
| #include <linux/sched_clock.h> |
| #include <linux/slab.h> |
| #include "timer-of.h" |
| |
| #define TIMER_CLK_EVT (1) |
| #define TIMER_CLK_SRC (2) |
| |
| #define TIMER_SYNC_TICKS (3) |
| |
| /* gpt */ |
| #define GPT_IRQ_EN_REG 0x00 |
| #define GPT_IRQ_ENABLE(val) BIT((val) - 1) |
| #define GPT_IRQ_ACK_REG 0x08 |
| #define GPT_IRQ_ACK(val) BIT((val) - 1) |
| |
| #define GPT_CTRL_REG(val) (0x10 * (val)) |
| #define GPT_CTRL_OP(val) (((val) & 0x3) << 4) |
| #define GPT_CTRL_OP_ONESHOT (0) |
| #define GPT_CTRL_OP_REPEAT (1) |
| #define GPT_CTRL_OP_FREERUN (3) |
| #define GPT_CTRL_CLEAR (2) |
| #define GPT_CTRL_ENABLE (1) |
| #define GPT_CTRL_DISABLE (0) |
| |
| #define GPT_CLK_REG(val) (0x04 + (0x10 * (val))) |
| #define GPT_CLK_SRC(val) (((val) & 0x1) << 4) |
| #define GPT_CLK_SRC_SYS13M (0) |
| #define GPT_CLK_SRC_RTC32K (1) |
| #define GPT_CLK_DIV1 (0x0) |
| #define GPT_CLK_DIV2 (0x1) |
| |
| #define GPT_CNT_REG(val) (0x08 + (0x10 * (val))) |
| #define GPT_CMP_REG(val) (0x0C + (0x10 * (val))) |
| |
| /* system timer */ |
| #define SYST_BASE (0x40) |
| |
| #define SYST_CON (SYST_BASE + 0x0) |
| #define SYST_VAL (SYST_BASE + 0x4) |
| |
| #define SYST_CON_REG(to) (timer_of_base(to) + SYST_CON) |
| #define SYST_VAL_REG(to) (timer_of_base(to) + SYST_VAL) |
| |
| /* |
| * SYST_CON_EN: Clock enable. Shall be set to |
| * - Start timer countdown. |
| * - Allow timeout ticks being updated. |
| * - Allow changing interrupt functions. |
| * |
| * SYST_CON_IRQ_EN: Set to allow interrupt. |
| * |
| * SYST_CON_IRQ_CLR: Set to clear interrupt. |
| */ |
| #define SYST_CON_EN BIT(0) |
| #define SYST_CON_IRQ_EN BIT(1) |
| #define SYST_CON_IRQ_CLR BIT(4) |
| |
| static void __iomem *gpt_sched_reg __read_mostly; |
| |
| static void mtk_syst_ack_irq(struct timer_of *to) |
| { |
| /* Clear and disable interrupt */ |
| writel(SYST_CON_EN, SYST_CON_REG(to)); |
| writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to)); |
| } |
| |
| static irqreturn_t mtk_syst_handler(int irq, void *dev_id) |
| { |
| struct clock_event_device *clkevt = dev_id; |
| struct timer_of *to = to_timer_of(clkevt); |
| |
| mtk_syst_ack_irq(to); |
| clkevt->event_handler(clkevt); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int mtk_syst_clkevt_next_event(unsigned long ticks, |
| struct clock_event_device *clkevt) |
| { |
| struct timer_of *to = to_timer_of(clkevt); |
| |
| /* Enable clock to allow timeout tick update later */ |
| writel(SYST_CON_EN, SYST_CON_REG(to)); |
| |
| /* |
| * Write new timeout ticks. Timer shall start countdown |
| * after timeout ticks are updated. |
| */ |
| writel(ticks, SYST_VAL_REG(to)); |
| |
| /* Enable interrupt */ |
| writel(SYST_CON_EN | SYST_CON_IRQ_EN, SYST_CON_REG(to)); |
| |
| return 0; |
| } |
| |
| static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt) |
| { |
| /* Clear any irq */ |
| mtk_syst_ack_irq(to_timer_of(clkevt)); |
| |
| /* Disable timer */ |
| writel(0, SYST_CON_REG(to_timer_of(clkevt))); |
| |
| return 0; |
| } |
| |
| static int mtk_syst_clkevt_resume(struct clock_event_device *clkevt) |
| { |
| return mtk_syst_clkevt_shutdown(clkevt); |
| } |
| |
| static int mtk_syst_clkevt_oneshot(struct clock_event_device *clkevt) |
| { |
| return 0; |
| } |
| |
| static u64 notrace mtk_gpt_read_sched_clock(void) |
| { |
| return readl_relaxed(gpt_sched_reg); |
| } |
| |
| static void mtk_gpt_clkevt_time_stop(struct timer_of *to, u8 timer) |
| { |
| u32 val; |
| |
| val = readl(timer_of_base(to) + GPT_CTRL_REG(timer)); |
| writel(val & ~GPT_CTRL_ENABLE, timer_of_base(to) + |
| GPT_CTRL_REG(timer)); |
| } |
| |
| static void mtk_gpt_clkevt_time_setup(struct timer_of *to, |
| unsigned long delay, u8 timer) |
| { |
| writel(delay, timer_of_base(to) + GPT_CMP_REG(timer)); |
| } |
| |
| static void mtk_gpt_clkevt_time_start(struct timer_of *to, |
| bool periodic, u8 timer) |
| { |
| u32 val; |
| |
| /* Acknowledge interrupt */ |
| writel(GPT_IRQ_ACK(timer), timer_of_base(to) + GPT_IRQ_ACK_REG); |
| |
| val = readl(timer_of_base(to) + GPT_CTRL_REG(timer)); |
| |
| /* Clear 2 bit timer operation mode field */ |
| val &= ~GPT_CTRL_OP(0x3); |
| |
| if (periodic) |
| val |= GPT_CTRL_OP(GPT_CTRL_OP_REPEAT); |
| else |
| val |= GPT_CTRL_OP(GPT_CTRL_OP_ONESHOT); |
| |
| writel(val | GPT_CTRL_ENABLE | GPT_CTRL_CLEAR, |
| timer_of_base(to) + GPT_CTRL_REG(timer)); |
| } |
| |
| static int mtk_gpt_clkevt_shutdown(struct clock_event_device *clk) |
| { |
| mtk_gpt_clkevt_time_stop(to_timer_of(clk), TIMER_CLK_EVT); |
| |
| return 0; |
| } |
| |
| static int mtk_gpt_clkevt_set_periodic(struct clock_event_device *clk) |
| { |
| struct timer_of *to = to_timer_of(clk); |
| |
| mtk_gpt_clkevt_time_stop(to, TIMER_CLK_EVT); |
| mtk_gpt_clkevt_time_setup(to, to->of_clk.period, TIMER_CLK_EVT); |
| mtk_gpt_clkevt_time_start(to, true, TIMER_CLK_EVT); |
| |
| return 0; |
| } |
| |
| static int mtk_gpt_clkevt_next_event(unsigned long event, |
| struct clock_event_device *clk) |
| { |
| struct timer_of *to = to_timer_of(clk); |
| |
| mtk_gpt_clkevt_time_stop(to, TIMER_CLK_EVT); |
| mtk_gpt_clkevt_time_setup(to, event, TIMER_CLK_EVT); |
| mtk_gpt_clkevt_time_start(to, false, TIMER_CLK_EVT); |
| |
| return 0; |
| } |
| |
| static irqreturn_t mtk_gpt_interrupt(int irq, void *dev_id) |
| { |
| struct clock_event_device *clkevt = (struct clock_event_device *)dev_id; |
| struct timer_of *to = to_timer_of(clkevt); |
| |
| /* Acknowledge timer0 irq */ |
| writel(GPT_IRQ_ACK(TIMER_CLK_EVT), timer_of_base(to) + GPT_IRQ_ACK_REG); |
| clkevt->event_handler(clkevt); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void |
| __init mtk_gpt_setup(struct timer_of *to, u8 timer, u8 option) |
| { |
| writel(GPT_CTRL_CLEAR | GPT_CTRL_DISABLE, |
| timer_of_base(to) + GPT_CTRL_REG(timer)); |
| |
| writel(GPT_CLK_SRC(GPT_CLK_SRC_SYS13M) | GPT_CLK_DIV1, |
| timer_of_base(to) + GPT_CLK_REG(timer)); |
| |
| writel(0x0, timer_of_base(to) + GPT_CMP_REG(timer)); |
| |
| writel(GPT_CTRL_OP(option) | GPT_CTRL_ENABLE, |
| timer_of_base(to) + GPT_CTRL_REG(timer)); |
| } |
| |
| static void mtk_gpt_enable_irq(struct timer_of *to, u8 timer) |
| { |
| u32 val; |
| |
| /* Disable all interrupts */ |
| writel(0x0, timer_of_base(to) + GPT_IRQ_EN_REG); |
| |
| /* Acknowledge all spurious pending interrupts */ |
| writel(0x3f, timer_of_base(to) + GPT_IRQ_ACK_REG); |
| |
| val = readl(timer_of_base(to) + GPT_IRQ_EN_REG); |
| writel(val | GPT_IRQ_ENABLE(timer), |
| timer_of_base(to) + GPT_IRQ_EN_REG); |
| } |
| |
| static struct timer_of to = { |
| .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK, |
| |
| .clkevt = { |
| .name = "mtk-clkevt", |
| .rating = 300, |
| .cpumask = cpu_possible_mask, |
| }, |
| |
| .of_irq = { |
| .flags = IRQF_TIMER | IRQF_IRQPOLL, |
| }, |
| }; |
| |
| static int __init mtk_syst_init(struct device_node *node) |
| { |
| int ret; |
| |
| to.clkevt.features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT; |
| to.clkevt.set_state_shutdown = mtk_syst_clkevt_shutdown; |
| to.clkevt.set_state_oneshot = mtk_syst_clkevt_oneshot; |
| to.clkevt.tick_resume = mtk_syst_clkevt_resume; |
| to.clkevt.set_next_event = mtk_syst_clkevt_next_event; |
| to.of_irq.handler = mtk_syst_handler; |
| |
| ret = timer_of_init(node, &to); |
| if (ret) |
| return ret; |
| |
| clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), |
| TIMER_SYNC_TICKS, 0xffffffff); |
| |
| return 0; |
| } |
| |
| static int __init mtk_gpt_init(struct device_node *node) |
| { |
| int ret; |
| |
| to.clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; |
| to.clkevt.set_state_shutdown = mtk_gpt_clkevt_shutdown; |
| to.clkevt.set_state_periodic = mtk_gpt_clkevt_set_periodic; |
| to.clkevt.set_state_oneshot = mtk_gpt_clkevt_shutdown; |
| to.clkevt.tick_resume = mtk_gpt_clkevt_shutdown; |
| to.clkevt.set_next_event = mtk_gpt_clkevt_next_event; |
| to.of_irq.handler = mtk_gpt_interrupt; |
| |
| ret = timer_of_init(node, &to); |
| if (ret) |
| return ret; |
| |
| /* Configure clock source */ |
| mtk_gpt_setup(&to, TIMER_CLK_SRC, GPT_CTRL_OP_FREERUN); |
| clocksource_mmio_init(timer_of_base(&to) + GPT_CNT_REG(TIMER_CLK_SRC), |
| node->name, timer_of_rate(&to), 300, 32, |
| clocksource_mmio_readl_up); |
| gpt_sched_reg = timer_of_base(&to) + GPT_CNT_REG(TIMER_CLK_SRC); |
| sched_clock_register(mtk_gpt_read_sched_clock, 32, timer_of_rate(&to)); |
| |
| /* Configure clock event */ |
| mtk_gpt_setup(&to, TIMER_CLK_EVT, GPT_CTRL_OP_REPEAT); |
| clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), |
| TIMER_SYNC_TICKS, 0xffffffff); |
| |
| mtk_gpt_enable_irq(&to, TIMER_CLK_EVT); |
| |
| return 0; |
| } |
| TIMER_OF_DECLARE(mtk_mt6577, "mediatek,mt6577-timer", mtk_gpt_init); |
| TIMER_OF_DECLARE(mtk_mt6765, "mediatek,mt6765-timer", mtk_syst_init); |