linux-imx

/*

 * at91sam926x_time.c - Periodic Interval Timer (PIT) for at91sam926x

 *

 * Copyright (C) 2005-2006 M. Amine SAYA, ATMEL Rousset, France

 * Revision  2005 M. Nicolas Diremdjian, ATMEL Rousset, France

 * Converted to ClockSource/ClockEvents by David Brownell.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

​

#define pr_fmt(fmt) "AT91: PIT: " fmt

​

#include <linux/clk.h>

#include <linux/clockchips.h>

#include <linux/interrupt.h>

#include <linux/irq.h>

#include <linux/kernel.h>

#include <linux/of.h>

#include <linux/of_address.h>

#include <linux/of_irq.h>

#include <linux/slab.h>

​

#define AT91_PIT_MR     0x00            /* Mode Register */

#define AT91_PIT_PITIEN         BIT(25)         /* Timer Interrupt Enable */

#define AT91_PIT_PITEN          BIT(24)         /* Timer Enabled */

#define AT91_PIT_PIV            GENMASK(19, 0)      /* Periodic Interval Value */

​

#define AT91_PIT_SR     0x04            /* Status Register */

#define AT91_PIT_PITS           BIT(0)          /* Timer Status */

​

#define AT91_PIT_PIVR       0x08            /* Periodic Interval Value Register */

#define AT91_PIT_PIIR       0x0c            /* Periodic Interval Image Register */

#define AT91_PIT_PICNT          GENMASK(31, 20)     /* Interval Counter */

#define AT91_PIT_CPIV           GENMASK(19, 0)      /* Inverval Value */

​

#define PIT_CPIV(x) ((x) & AT91_PIT_CPIV)

#define PIT_PICNT(x)    (((x) & AT91_PIT_PICNT) >> 20)

​

struct pit_data {

    struct clock_event_device   clkevt;

    struct clocksource      clksrc;

​

    void __iomem    *base;

    u32     cycle;

    u32     cnt;

    unsigned int    irq;

    struct clk  *mck;

};

​

static inline struct pit_data *clksrc_to_pit_data(struct clocksource *clksrc)

{

    return container_of(clksrc, struct pit_data, clksrc);

}

​

static inline struct pit_data *clkevt_to_pit_data(struct clock_event_device *clkevt)

{

    return container_of(clkevt, struct pit_data, clkevt);

}

​

static inline unsigned int pit_read(void __iomem *base, unsigned int reg_offset)

{