diff options
Diffstat (limited to 'drivers/clocksource/timer-milbeaut.c')
| -rw-r--r-- | drivers/clocksource/timer-milbeaut.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-milbeaut.c b/drivers/clocksource/timer-milbeaut.c new file mode 100644 index 000000000..fa9fb4eac --- /dev/null +++ b/drivers/clocksource/timer-milbeaut.c @@ -0,0 +1,189 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Socionext Inc. + */ + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqreturn.h> +#include <linux/sched_clock.h> +#include "timer-of.h" + +#define MLB_TMR_TMCSR_OFS 0x0 +#define MLB_TMR_TMR_OFS 0x4 +#define MLB_TMR_TMRLR1_OFS 0x8 +#define MLB_TMR_TMRLR2_OFS 0xc +#define MLB_TMR_REGSZPCH 0x10 + +#define MLB_TMR_TMCSR_OUTL BIT(5) +#define MLB_TMR_TMCSR_RELD BIT(4) +#define MLB_TMR_TMCSR_INTE BIT(3) +#define MLB_TMR_TMCSR_UF BIT(2) +#define MLB_TMR_TMCSR_CNTE BIT(1) +#define MLB_TMR_TMCSR_TRG BIT(0) + +#define MLB_TMR_TMCSR_CSL_DIV2 0 +#define MLB_TMR_DIV_CNT 2 + +#define MLB_TMR_SRC_CH 1 +#define MLB_TMR_EVT_CH 0 + +#define MLB_TMR_SRC_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_SRC_CH) +#define MLB_TMR_EVT_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_EVT_CH) + +#define MLB_TMR_SRC_TMCSR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMCSR_OFS) +#define MLB_TMR_SRC_TMR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMR_OFS) +#define MLB_TMR_SRC_TMRLR1_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR1_OFS) +#define MLB_TMR_SRC_TMRLR2_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR2_OFS) + +#define MLB_TMR_EVT_TMCSR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMCSR_OFS) +#define MLB_TMR_EVT_TMR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMR_OFS) +#define MLB_TMR_EVT_TMRLR1_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR1_OFS) +#define MLB_TMR_EVT_TMRLR2_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR2_OFS) + +#define MLB_TIMER_RATING 500 +#define MLB_TIMER_ONESHOT 0 +#define MLB_TIMER_PERIODIC 1 + +static irqreturn_t mlb_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *clk = dev_id; + struct timer_of *to = to_timer_of(clk); + u32 val; + + val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); + val &= ~MLB_TMR_TMCSR_UF; + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); + + clk->event_handler(clk); + + return IRQ_HANDLED; +} + +static void mlb_evt_timer_start(struct timer_of *to, bool periodic) +{ + u32 val = MLB_TMR_TMCSR_CSL_DIV2; + + val |= MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_TRG | MLB_TMR_TMCSR_INTE; + if (periodic) + val |= MLB_TMR_TMCSR_RELD; + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); +} + +static void mlb_evt_timer_stop(struct timer_of *to) +{ + u32 val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); + + val &= ~MLB_TMR_TMCSR_CNTE; + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); +} + +static void mlb_evt_timer_register_count(struct timer_of *to, unsigned long cnt) +{ + writel_relaxed(cnt, timer_of_base(to) + MLB_TMR_EVT_TMRLR1_OFS); +} + +static int mlb_set_state_periodic(struct clock_event_device *clk) +{ + struct timer_of *to = to_timer_of(clk); + + mlb_evt_timer_stop(to); + mlb_evt_timer_register_count(to, to->of_clk.period); + mlb_evt_timer_start(to, MLB_TIMER_PERIODIC); + return 0; +} + +static int mlb_set_state_oneshot(struct clock_event_device *clk) +{ + struct timer_of *to = to_timer_of(clk); + + mlb_evt_timer_stop(to); + mlb_evt_timer_start(to, MLB_TIMER_ONESHOT); + return 0; +} + +static int mlb_set_state_shutdown(struct clock_event_device *clk) +{ + struct timer_of *to = to_timer_of(clk); + + mlb_evt_timer_stop(to); + return 0; +} + +static int mlb_clkevt_next_event(unsigned long event, + struct clock_event_device *clk) +{ + struct timer_of *to = to_timer_of(clk); + + mlb_evt_timer_stop(to); + mlb_evt_timer_register_count(to, event); + mlb_evt_timer_start(to, MLB_TIMER_ONESHOT); + return 0; +} + +static int mlb_config_clock_source(struct timer_of *to) +{ + u32 val = MLB_TMR_TMCSR_CSL_DIV2; + + writel_relaxed(val, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS); + writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR1_OFS); + writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR2_OFS); + val |= MLB_TMR_TMCSR_RELD | MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_TRG; + writel_relaxed(val, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS); + return 0; +} + +static int mlb_config_clock_event(struct timer_of *to) +{ + writel_relaxed(0, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS); + return 0; +} + +static struct timer_of to = { + .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK, + + .clkevt = { + .name = "mlb-clkevt", + .rating = MLB_TIMER_RATING, + .cpumask = cpu_possible_mask, + .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT, + .set_state_oneshot = mlb_set_state_oneshot, + .set_state_periodic = mlb_set_state_periodic, + .set_state_shutdown = mlb_set_state_shutdown, + .set_next_event = mlb_clkevt_next_event, + }, + + .of_irq = { + .flags = IRQF_TIMER | IRQF_IRQPOLL, + .handler = mlb_timer_interrupt, + }, +}; + +static u64 notrace mlb_timer_sched_read(void) +{ + return ~readl_relaxed(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS); +} + +static int __init mlb_timer_init(struct device_node *node) +{ + int ret; + unsigned long rate; + + ret = timer_of_init(node, &to); + if (ret) + return ret; + + rate = timer_of_rate(&to) / MLB_TMR_DIV_CNT; + mlb_config_clock_source(&to); + clocksource_mmio_init(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS, + node->name, rate, MLB_TIMER_RATING, 32, + clocksource_mmio_readl_down); + sched_clock_register(mlb_timer_sched_read, 32, rate); + mlb_config_clock_event(&to); + clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), 15, + 0xffffffff); + return 0; +} +TIMER_OF_DECLARE(mlb_peritimer, "socionext,milbeaut-timer", + mlb_timer_init); |