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//==========================================================================

//

//      devs/watchdog/arm/at91/watchdog_at91.cxx

//

//      Watchdog implementation for ARM AT91 CPU

//

//==========================================================================

//####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

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// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

//

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//

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// or inline functions from this file, or you compile this file and link it

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//####ECOSGPLCOPYRIGHTEND####

//==========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):    tkoeller

// Contributors: tkoeller

// Date:         2002-05-05

// Purpose:      Watchdog class implementation

// Description:  Contains an implementation of the Watchdog class for use

//               with the ATMEL AT91 watchdog timer.

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include <pkgconf/kernel.h>

#include <pkgconf/infra.h>

#include <pkgconf/kernel.h>

#include <pkgconf/watchdog.h>

#include <pkgconf/devs_watchdog_arm_at91.h>

#include <cyg/infra/cyg_type.h>

#include <cyg/infra/cyg_ass.h>

#include <cyg/infra/cyg_trac.h>

#include <cyg/hal/hal_io.h>

#include <cyg/hal/plf_io.h>

#include <cyg/hal/hal_diag.h>

#include <cyg/io/watchdog.hxx>

#if !defined(CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT)

#include <cyg/hal/hal_platform_ints.h>

#include <cyg/kernel/intr.hxx>

#endif

#define MCLK_FREQUENCY_KHZ  32768

#define MAX_TICKS           0x0000ffff

#define BASE_TICKS          (MCLK_FREQUENCY_KHZ * CYGNUM_DEVS_WATCHDOG_ARM_AT91_DESIRED_TMEOUT_MS)

#if   BASE_TICKS / 8 <= MAX_TICKS

#define DIVIDER 0

#define DIV_FACTOR 8

#elif BASE_TICKS / 32 <= MAX_TICKS

#define DIVIDER 1

#define DIV_FACTOR 32

#elif BASE_TICKS / 128 <= MAX_TICKS

#define DIVIDER 2

#define DIV_FACTOR 128

#elif BASE_TICKS / 1024 <= MAX_TICKS

#define DIVIDER 3

#define DIV_FACTOR 1024

#else

#error Desired resolution beyond hardware capabilities

#endif

#define TICKS       ((BASE_TICKS / DIV_FACTOR) | 0xfff)

#define RESOLUTION  ((cyg_uint64) (TICKS * DIV_FACTOR ) * 1000000 / MCLK_FREQUENCY_KHZ)

#if defined(CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT)

#define OMRVAL  (AT91_WD_OMR_OKEY | AT91_WD_OMR_RSTEN | AT91_WD_OMR_WDEN)

void

Cyg_Watchdog::init_hw(void)

{

  CYG_REPORT_FUNCTION();

  CYG_REPORT_FUNCARGVOID();

  resolution = RESOLUTION;

  CYG_REPORT_RETURN();

}

#else /* defined(CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT) */

#define OMRVAL  (AT91_WD_OMR_OKEY | AT91_WD_OMR_IRQEN | AT91_WD_OMR_WDEN)

#define INT_PRIO    7

static void *

operator new(size_t size)

{

  static cyg_uint8 buf[sizeof (Cyg_Interrupt)];

  CYG_REPORT_FUNCTION();

  CYG_REPORT_FUNCARG1XV(size);

  CYG_ASSERTC(size == sizeof buf);

  CYG_REPORT_RETVAL(buf);

  return buf;

}

static cyg_uint32

isr(cyg_vector vector, CYG_ADDRWORD data)

{

  Cyg_Watchdog &wd = *(Cyg_Watchdog *) data;

  CYG_REPORT_FUNCTION();

  CYG_REPORT_FUNCARG2XV(vector, data);

  wd.trigger();

  Cyg_Interrupt::acknowledge_interrupt(CYGNUM_HAL_INTERRUPT_WATCHDOG);

  CYG_REPORT_RETVAL(Cyg_Interrupt::HANDLED);

  return Cyg_Interrupt::HANDLED;

}

static Cyg_Interrupt * wdint;

void

Cyg_Watchdog::init_hw(void)

{

  CYG_REPORT_FUNCTION();

  CYG_REPORT_FUNCARGVOID();

  resolution = RESOLUTION;

  wdint = new Cyg_Interrupt(

    CYGNUM_HAL_INTERRUPT_WATCHDOG,

    INT_PRIO,

    (CYG_ADDRWORD) this,

    isr,

    NULL

  );

  wdint->configure_interrupt(CYGNUM_HAL_INTERRUPT_WATCHDOG, false, true);

  wdint->attach();

  wdint->acknowledge_interrupt(CYGNUM_HAL_INTERRUPT_WATCHDOG);

  wdint->unmask_interrupt(CYGNUM_HAL_INTERRUPT_WATCHDOG);

  CYG_REPORT_RETURN();

}

#endif  /* defined(CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT) */

/*

 * Reset watchdog timer. This needs to be called regularly to prevent

 * the watchdog from firing.

 */

void

Cyg_Watchdog::reset(void)

{

  CYG_REPORT_FUNCTION();

  CYG_REPORT_FUNCARGVOID();

  /* Write magic code to reset the watchdog. */

  HAL_WRITE_UINT32(AT91_WD + AT91_WD_CR, AT91_WD_CR_RSTKEY);

  CYG_REPORT_RETURN();

}

/*

 * Start watchdog to generate a hardware reset

 * or interrupt when expiring.

 */

void

Cyg_Watchdog::start(void)

{

  CYG_REPORT_FUNCTION();

  CYG_REPORT_FUNCARGVOID();

  HAL_WRITE_UINT32(AT91_WD + AT91_WD_OMR, AT91_WD_OMR_OKEY);

  HAL_WRITE_UINT32(

    AT91_WD + AT91_WD_CMR,

    AT91_WD_CMR_CKEY | ((TICKS >> 10) & AT91_WD_CMR_HPCV) | DIVIDER

  );

  HAL_WRITE_UINT32(AT91_WD + AT91_WD_CR, AT91_WD_CR_RSTKEY);

  HAL_WRITE_UINT32(AT91_WD + AT91_WD_OMR, OMRVAL);

  CYG_REPORT_RETURN();

}