// 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);
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