drivers/clocksource/timer-milbeaut.c

Source file repositories/reference/linux-study-clean/drivers/clocksource/timer-milbeaut.c

File Facts

System
Linux kernel
Corpus path
drivers/clocksource/timer-milbeaut.c
Extension
.c
Size
5220 bytes
Lines
190
Domain
Driver Families
Bucket
drivers/clocksource
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// 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);

Annotation

Implementation Notes