root/include/linux/atmel_tc.h

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/*
 * Timer/Counter Unit (TC) registers.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#ifndef ATMEL_TC_H
#define ATMEL_TC_H

#include <linux/compiler.h>
#include <linux/list.h>

/*
 * Many 32-bit Atmel SOCs include one or more TC blocks, each of which holds
 * three general-purpose 16-bit timers.  These timers share one register bank.
 * Depending on the SOC, each timer may have its own clock and IRQ, or those
 * may be shared by the whole TC block.
 *
 * These TC blocks may have up to nine external pins:  TCLK0..2 signals for
 * clocks or clock gates, and per-timer TIOA and TIOB signals used for PWM
 * or triggering.  Those pins need to be set up for use with the TC block,
 * else they will be used as GPIOs or for a different controller.
 *
 * Although we expect each TC block to have a platform_device node, those
 * nodes are not what drivers bind to.  Instead, they ask for a specific
 * TC block, by number ... which is a common approach on systems with many
 * timers.  Then they use clk_get() and platform_get_irq() to get clock and
 * IRQ resources.
 */

struct clk;

/**
 * struct atmel_tcb_config - SoC data for a Timer/Counter Block
 * @counter_width: size in bits of a timer counter register
 */
struct atmel_tcb_config {
        size_t  counter_width;
};

/**
 * struct atmel_tc - information about a Timer/Counter Block
 * @pdev: physical device
 * @regs: mapping through which the I/O registers can be accessed
 * @id: block id
 * @tcb_config: configuration data from SoC
 * @irq: irq for each of the three channels
 * @clk: internal clock source for each of the three channels
 * @node: list node, for tclib internal use
 * @allocated: if already used, for tclib internal use
 *
 * On some platforms, each TC channel has its own clocks and IRQs,
 * while on others, all TC channels share the same clock and IRQ.
 * Drivers should clk_enable() all the clocks they need even though
 * all the entries in @clk may point to the same physical clock.
 * Likewise, drivers should request irqs independently for each
 * channel, but they must use IRQF_SHARED in case some of the entries
 * in @irq are actually the same IRQ.
 */
struct atmel_tc {
        struct platform_device  *pdev;
        void __iomem            *regs;
        int                     id;
        const struct atmel_tcb_config *tcb_config;
        int                     irq[3];
        struct clk              *clk[3];
        struct list_head        node;
        bool                    allocated;
};

extern struct atmel_tc *atmel_tc_alloc(unsigned block);
extern void atmel_tc_free(struct atmel_tc *tc);

/* platform-specific ATMEL_TC_TIMER_CLOCKx divisors (0 means 32KiHz) */
extern const u8 atmel_tc_divisors[5];


/*
 * Two registers have block-wide controls.  These are: configuring the three
 * "external" clocks (or event sources) used by the timer channels; and
 * synchronizing the timers by resetting them all at once.
 *
 * "External" can mean "external to chip" using the TCLK0, TCLK1, or TCLK2
 * signals.  Or, it can mean "external to timer", using the TIOA output from
 * one of the other two timers that's being run in waveform mode.
 */

#define ATMEL_TC_BCR    0xc0            /* TC Block Control Register */
#define     ATMEL_TC_SYNC       (1 << 0)        /* synchronize timers */

#define ATMEL_TC_BMR    0xc4            /* TC Block Mode Register */
#define     ATMEL_TC_TC0XC0S    (3 << 0)        /* external clock 0 source */
#define        ATMEL_TC_TC0XC0S_TCLK0   (0 << 0)
#define        ATMEL_TC_TC0XC0S_NONE    (1 << 0)
#define        ATMEL_TC_TC0XC0S_TIOA1   (2 << 0)
#define        ATMEL_TC_TC0XC0S_TIOA2   (3 << 0)
#define     ATMEL_TC_TC1XC1S    (3 << 2)        /* external clock 1 source */
#define        ATMEL_TC_TC1XC1S_TCLK1   (0 << 2)
#define        ATMEL_TC_TC1XC1S_NONE    (1 << 2)
#define        ATMEL_TC_TC1XC1S_TIOA0   (2 << 2)
#define        ATMEL_TC_TC1XC1S_TIOA2   (3 << 2)
#define     ATMEL_TC_TC2XC2S    (3 << 4)        /* external clock 2 source */
#define        ATMEL_TC_TC2XC2S_TCLK2   (0 << 4)
#define        ATMEL_TC_TC2XC2S_NONE    (1 << 4)
#define        ATMEL_TC_TC2XC2S_TIOA0   (2 << 4)
#define        ATMEL_TC_TC2XC2S_TIOA1   (3 << 4)


/*
 * Each TC block has three "channels", each with one counter and controls.
 *
 * Note that the semantics of ATMEL_TC_TIMER_CLOCKx (input clock selection
 * when it's not "external") is silicon-specific.  AT91 platforms use one
 * set of definitions; AVR32 platforms use a different set.  Don't hard-wire
 * such knowledge into your code, use the global "atmel_tc_divisors" ...
 * where index N is the divisor for clock N+1, else zero to indicate it uses
 * the 32 KiHz clock.
 *
 * The timers can be chained in various ways, and operated in "waveform"
 * generation mode (including PWM) or "capture" mode (to time events).  In
 * both modes, behavior can be configured in many ways.
 *
 * Each timer has two I/O pins, TIOA and TIOB.  Waveform mode uses TIOA as a
 * PWM output, and TIOB as either another PWM or as a trigger.  Capture mode
 * uses them only as inputs.
 */
#define ATMEL_TC_CHAN(idx)      ((idx)*0x40)
#define ATMEL_TC_REG(idx, reg)  (ATMEL_TC_CHAN(idx) + ATMEL_TC_ ## reg)

#define ATMEL_TC_CCR    0x00            /* Channel Control Register */
#define     ATMEL_TC_CLKEN      (1 << 0)        /* clock enable */
#define     ATMEL_TC_CLKDIS     (1 << 1)        /* clock disable */
#define     ATMEL_TC_SWTRG      (1 << 2)        /* software trigger */

#define ATMEL_TC_CMR    0x04            /* Channel Mode Register */

/* Both modes share some CMR bits */
#define     ATMEL_TC_TCCLKS     (7 << 0)        /* clock source */
#define        ATMEL_TC_TIMER_CLOCK1    (0 << 0)
#define        ATMEL_TC_TIMER_CLOCK2    (1 << 0)
#define        ATMEL_TC_TIMER_CLOCK3    (2 << 0)
#define        ATMEL_TC_TIMER_CLOCK4    (3 << 0)
#define        ATMEL_TC_TIMER_CLOCK5    (4 << 0)
#define        ATMEL_TC_XC0             (5 << 0)
#define        ATMEL_TC_XC1             (6 << 0)
#define        ATMEL_TC_XC2             (7 << 0)
#define     ATMEL_TC_CLKI       (1 << 3)        /* clock invert */
#define     ATMEL_TC_BURST      (3 << 4)        /* clock gating */
#define        ATMEL_TC_GATE_NONE       (0 << 4)
#define        ATMEL_TC_GATE_XC0        (1 << 4)
#define        ATMEL_TC_GATE_XC1        (2 << 4)
#define        ATMEL_TC_GATE_XC2        (3 << 4)
#define     ATMEL_TC_WAVE       (1 << 15)       /* true = Waveform mode */

/* CAPTURE mode CMR bits */
#define     ATMEL_TC_LDBSTOP    (1 << 6)        /* counter stops on RB load */
#define     ATMEL_TC_LDBDIS     (1 << 7)        /* counter disable on RB load */
#define     ATMEL_TC_ETRGEDG    (3 << 8)        /* external trigger edge */
#define        ATMEL_TC_ETRGEDG_NONE    (0 << 8)
#define        ATMEL_TC_ETRGEDG_RISING  (1 << 8)
#define        ATMEL_TC_ETRGEDG_FALLING (2 << 8)
#define        ATMEL_TC_ETRGEDG_BOTH    (3 << 8)
#define     ATMEL_TC_ABETRG     (1 << 10)       /* external trigger is TIOA? */
#define     ATMEL_TC_CPCTRG     (1 << 14)       /* RC compare trigger enable */
#define     ATMEL_TC_LDRA       (3 << 16)       /* RA loading edge (of TIOA) */
#define        ATMEL_TC_LDRA_NONE       (0 << 16)
#define        ATMEL_TC_LDRA_RISING     (1 << 16)
#define        ATMEL_TC_LDRA_FALLING    (2 << 16)
#define        ATMEL_TC_LDRA_BOTH       (3 << 16)
#define     ATMEL_TC_LDRB       (3 << 18)       /* RB loading edge (of TIOA) */
#define        ATMEL_TC_LDRB_NONE       (0 << 18)
#define        ATMEL_TC_LDRB_RISING     (1 << 18)
#define        ATMEL_TC_LDRB_FALLING    (2 << 18)
#define        ATMEL_TC_LDRB_BOTH       (3 << 18)

/* WAVEFORM mode CMR bits */
#define     ATMEL_TC_CPCSTOP    (1 <<  6)       /* RC compare stops counter */
#define     ATMEL_TC_CPCDIS     (1 <<  7)       /* RC compare disables counter */
#define     ATMEL_TC_EEVTEDG    (3 <<  8)       /* external event edge */
#define        ATMEL_TC_EEVTEDG_NONE    (0 << 8)
#define        ATMEL_TC_EEVTEDG_RISING  (1 << 8)
#define        ATMEL_TC_EEVTEDG_FALLING (2 << 8)
#define        ATMEL_TC_EEVTEDG_BOTH    (3 << 8)
#define     ATMEL_TC_EEVT       (3 << 10)       /* external event source */
#define        ATMEL_TC_EEVT_TIOB       (0 << 10)
#define        ATMEL_TC_EEVT_XC0        (1 << 10)
#define        ATMEL_TC_EEVT_XC1        (2 << 10)
#define        ATMEL_TC_EEVT_XC2        (3 << 10)
#define     ATMEL_TC_ENETRG     (1 << 12)       /* external event is trigger */
#define     ATMEL_TC_WAVESEL    (3 << 13)       /* waveform type */
#define        ATMEL_TC_WAVESEL_UP      (0 << 13)
#define        ATMEL_TC_WAVESEL_UPDOWN  (1 << 13)
#define        ATMEL_TC_WAVESEL_UP_AUTO (2 << 13)
#define        ATMEL_TC_WAVESEL_UPDOWN_AUTO (3 << 13)
#define     ATMEL_TC_ACPA       (3 << 16)       /* RA compare changes TIOA */
#define        ATMEL_TC_ACPA_NONE       (0 << 16)
#define        ATMEL_TC_ACPA_SET        (1 << 16)
#define        ATMEL_TC_ACPA_CLEAR      (2 << 16)
#define        ATMEL_TC_ACPA_TOGGLE     (3 << 16)
#define     ATMEL_TC_ACPC       (3 << 18)       /* RC compare changes TIOA */
#define        ATMEL_TC_ACPC_NONE       (0 << 18)
#define        ATMEL_TC_ACPC_SET        (1 << 18)
#define        ATMEL_TC_ACPC_CLEAR      (2 << 18)
#define        ATMEL_TC_ACPC_TOGGLE     (3 << 18)
#define     ATMEL_TC_AEEVT      (3 << 20)       /* external event changes TIOA */
#define        ATMEL_TC_AEEVT_NONE      (0 << 20)
#define        ATMEL_TC_AEEVT_SET       (1 << 20)
#define        ATMEL_TC_AEEVT_CLEAR     (2 << 20)
#define        ATMEL_TC_AEEVT_TOGGLE    (3 << 20)
#define     ATMEL_TC_ASWTRG     (3 << 22)       /* software trigger changes TIOA */
#define        ATMEL_TC_ASWTRG_NONE     (0 << 22)
#define        ATMEL_TC_ASWTRG_SET      (1 << 22)
#define        ATMEL_TC_ASWTRG_CLEAR    (2 << 22)
#define        ATMEL_TC_ASWTRG_TOGGLE   (3 << 22)
#define     ATMEL_TC_BCPB       (3 << 24)       /* RB compare changes TIOB */
#define        ATMEL_TC_BCPB_NONE       (0 << 24)
#define        ATMEL_TC_BCPB_SET        (1 << 24)
#define        ATMEL_TC_BCPB_CLEAR      (2 << 24)
#define        ATMEL_TC_BCPB_TOGGLE     (3 << 24)
#define     ATMEL_TC_BCPC       (3 << 26)       /* RC compare changes TIOB */
#define        ATMEL_TC_BCPC_NONE       (0 << 26)
#define        ATMEL_TC_BCPC_SET        (1 << 26)
#define        ATMEL_TC_BCPC_CLEAR      (2 << 26)
#define        ATMEL_TC_BCPC_TOGGLE     (3 << 26)
#define     ATMEL_TC_BEEVT      (3 << 28)       /* external event changes TIOB */
#define        ATMEL_TC_BEEVT_NONE      (0 << 28)
#define        ATMEL_TC_BEEVT_SET       (1 << 28)
#define        ATMEL_TC_BEEVT_CLEAR     (2 << 28)
#define        ATMEL_TC_BEEVT_TOGGLE    (3 << 28)
#define     ATMEL_TC_BSWTRG     (3 << 30)       /* software trigger changes TIOB */
#define        ATMEL_TC_BSWTRG_NONE     (0 << 30)
#define        ATMEL_TC_BSWTRG_SET      (1 << 30)
#define        ATMEL_TC_BSWTRG_CLEAR    (2 << 30)
#define        ATMEL_TC_BSWTRG_TOGGLE   (3 << 30)

#define ATMEL_TC_CV     0x10            /* counter Value */
#define ATMEL_TC_RA     0x14            /* register A */
#define ATMEL_TC_RB     0x18            /* register B */
#define ATMEL_TC_RC     0x1c            /* register C */

#define ATMEL_TC_SR     0x20            /* status (read-only) */
/* Status-only flags */
#define     ATMEL_TC_CLKSTA     (1 << 16)       /* clock enabled */
#define     ATMEL_TC_MTIOA      (1 << 17)       /* TIOA mirror */
#define     ATMEL_TC_MTIOB      (1 << 18)       /* TIOB mirror */

#define ATMEL_TC_IER    0x24            /* interrupt enable (write-only) */
#define ATMEL_TC_IDR    0x28            /* interrupt disable (write-only) */
#define ATMEL_TC_IMR    0x2c            /* interrupt mask (read-only) */

/* Status and IRQ flags */
#define     ATMEL_TC_COVFS      (1 <<  0)       /* counter overflow */
#define     ATMEL_TC_LOVRS      (1 <<  1)       /* load overrun */
#define     ATMEL_TC_CPAS       (1 <<  2)       /* RA compare */
#define     ATMEL_TC_CPBS       (1 <<  3)       /* RB compare */
#define     ATMEL_TC_CPCS       (1 <<  4)       /* RC compare */
#define     ATMEL_TC_LDRAS      (1 <<  5)       /* RA loading */
#define     ATMEL_TC_LDRBS      (1 <<  6)       /* RB loading */
#define     ATMEL_TC_ETRGS      (1 <<  7)       /* external trigger */
#define     ATMEL_TC_ALL_IRQ    (ATMEL_TC_COVFS | ATMEL_TC_LOVRS | \
                                 ATMEL_TC_CPAS | ATMEL_TC_CPBS | \
                                 ATMEL_TC_CPCS | ATMEL_TC_LDRAS | \
                                 ATMEL_TC_LDRBS | ATMEL_TC_ETRGS) \
                                 /* all IRQs */

#endif

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