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// SPDX-License-Identifier: GPL-2.0
/*
* Amlogic Meson6 SoCs timer handling.
*
* Copyright (C) 2014 Carlo Caione <carlo@caione.org>
*
* Based on code from Amlogic, Inc
*/
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqreturn.h>
#include <linux/sched_clock.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#ifdef CONFIG_ARM
#include <linux/delay.h>
#endif
#define MESON_ISA_TIMER_MUX 0x00
#define MESON_ISA_TIMER_MUX_TIMERD_EN BIT(19)
#define MESON_ISA_TIMER_MUX_TIMERC_EN BIT(18)
#define MESON_ISA_TIMER_MUX_TIMERB_EN BIT(17)
#define MESON_ISA_TIMER_MUX_TIMERA_EN BIT(16)
#define MESON_ISA_TIMER_MUX_TIMERD_MODE BIT(15)
#define MESON_ISA_TIMER_MUX_TIMERC_MODE BIT(14)
#define MESON_ISA_TIMER_MUX_TIMERB_MODE BIT(13)
#define MESON_ISA_TIMER_MUX_TIMERA_MODE BIT(12)
#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_MASK GENMASK(10, 8)
#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_SYSTEM_CLOCK 0x0
#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_1US 0x1
#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_10US 0x2
#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_100US 0x3
#define MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_1MS 0x4
#define MESON_ISA_TIMER_MUX_TIMERD_INPUT_CLOCK_MASK GENMASK(7, 6)
#define MESON_ISA_TIMER_MUX_TIMERC_INPUT_CLOCK_MASK GENMASK(5, 4)
#define MESON_ISA_TIMER_MUX_TIMERB_INPUT_CLOCK_MASK GENMASK(3, 2)
#define MESON_ISA_TIMER_MUX_TIMERA_INPUT_CLOCK_MASK GENMASK(1, 0)
#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_1US 0x0
#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_10US 0x1
#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_100US 0x0
#define MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_1MS 0x3
#define MESON_ISA_TIMERA 0x04
#define MESON_ISA_TIMERB 0x08
#define MESON_ISA_TIMERC 0x0c
#define MESON_ISA_TIMERD 0x10
#define MESON_ISA_TIMERE 0x14
static void __iomem *timer_base;
#ifdef CONFIG_ARM
static unsigned long meson6_read_current_timer(void)
{
return readl_relaxed(timer_base + MESON_ISA_TIMERE);
}
static struct delay_timer meson6_delay_timer = {
.read_current_timer = meson6_read_current_timer,
.freq = 1000 * 1000,
};
#endif
static u64 notrace meson6_timer_sched_read(void)
{
return (u64)readl(timer_base + MESON_ISA_TIMERE);
}
static void meson6_clkevt_time_stop(void)
{
u32 val = readl(timer_base + MESON_ISA_TIMER_MUX);
writel(val & ~MESON_ISA_TIMER_MUX_TIMERA_EN,
timer_base + MESON_ISA_TIMER_MUX);
}
static void meson6_clkevt_time_setup(unsigned long delay)
{
writel(delay, timer_base + MESON_ISA_TIMERA);
}
static void meson6_clkevt_time_start(bool periodic)
{
u32 val = readl(timer_base + MESON_ISA_TIMER_MUX);
if (periodic)
val |= MESON_ISA_TIMER_MUX_TIMERA_MODE;
else
val &= ~MESON_ISA_TIMER_MUX_TIMERA_MODE;
writel(val | MESON_ISA_TIMER_MUX_TIMERA_EN,
timer_base + MESON_ISA_TIMER_MUX);
}
static int meson6_shutdown(struct clock_event_device *evt)
{
meson6_clkevt_time_stop();
return 0;
}
static int meson6_set_oneshot(struct clock_event_device *evt)
{
meson6_clkevt_time_stop();
meson6_clkevt_time_start(false);
return 0;
}
static int meson6_set_periodic(struct clock_event_device *evt)
{
meson6_clkevt_time_stop();
meson6_clkevt_time_setup(USEC_PER_SEC / HZ - 1);
meson6_clkevt_time_start(true);
return 0;
}
static int meson6_clkevt_next_event(unsigned long evt,
struct clock_event_device *unused)
{
meson6_clkevt_time_stop();
meson6_clkevt_time_setup(evt);
meson6_clkevt_time_start(false);
return 0;
}
static struct clock_event_device meson6_clockevent = {
.name = "meson6_tick",
.rating = 400,
.features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT,
.set_state_shutdown = meson6_shutdown,
.set_state_periodic = meson6_set_periodic,
.set_state_oneshot = meson6_set_oneshot,
.tick_resume = meson6_shutdown,
.set_next_event = meson6_clkevt_next_event,
};
static irqreturn_t meson6_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = (struct clock_event_device *)dev_id;
evt->event_handler(evt);
return IRQ_HANDLED;
}
static int __init meson6_timer_init(struct device_node *node)
{
u32 val;
int ret, irq;
timer_base = of_io_request_and_map(node, 0, "meson6-timer");
if (IS_ERR(timer_base)) {
pr_err("Can't map registers\n");
return -ENXIO;
}
irq = irq_of_parse_and_map(node, 0);
if (irq <= 0) {
pr_err("Can't parse IRQ\n");
return -EINVAL;
}
/* Set 1us for timer E */
val = readl(timer_base + MESON_ISA_TIMER_MUX);
val &= ~MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_MASK;
val |= FIELD_PREP(MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_MASK,
MESON_ISA_TIMER_MUX_TIMERE_INPUT_CLOCK_1US);
writel(val, timer_base + MESON_ISA_TIMER_MUX);
sched_clock_register(meson6_timer_sched_read, 32, USEC_PER_SEC);
clocksource_mmio_init(timer_base + MESON_ISA_TIMERE, node->name,
1000 * 1000, 300, 32, clocksource_mmio_readl_up);
/* Timer A base 1us */
val &= ~MESON_ISA_TIMER_MUX_TIMERA_INPUT_CLOCK_MASK;
val |= FIELD_PREP(MESON_ISA_TIMER_MUX_TIMERA_INPUT_CLOCK_MASK,
MESON_ISA_TIMER_MUX_TIMERABCD_INPUT_CLOCK_1US);
writel(val, timer_base + MESON_ISA_TIMER_MUX);
/* Stop the timer A */
meson6_clkevt_time_stop();
ret = request_irq(irq, meson6_timer_interrupt,
IRQF_TIMER | IRQF_IRQPOLL, "meson6_timer",
&meson6_clockevent);
if (ret) {
pr_warn("failed to setup irq %d\n", irq);
return ret;
}
meson6_clockevent.cpumask = cpu_possible_mask;
meson6_clockevent.irq = irq;
clockevents_config_and_register(&meson6_clockevent, USEC_PER_SEC,
1, 0xfffe);
#ifdef CONFIG_ARM
/* Also use MESON_ISA_TIMERE for delays */
register_current_timer_delay(&meson6_delay_timer);
#endif
return 0;
}
TIMER_OF_DECLARE(meson6, "amlogic,meson6-timer",
meson6_timer_init);
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