ds1672.cxx

ecos移植到R8H系列的源码。源码包来自http://www.cetoni.de/develop/develop_ecosh8s_en.html

//==========================================================================
//
//      devs/wallclock/ds1672.inl
//
//      Wallclock implementation for Dallas 1672
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
// Copyright (C) 2003 Gary Thomas
//
// eCos 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 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):     gthomas
// Contributors:  uwe kindler
// Date:          2003-11-26
// Purpose:       Wallclock driver for Dallas 1672
//
//####DESCRIPTIONEND####
//
//==========================================================================


//==========================================================================
//                               INCLUDES
//==========================================================================
#include <pkgconf/hal.h>                  // Platform specific configury
#include <pkgconf/wallclock.h>            // Wallclock device config

#include <cyg/hal/hal_io.h>               // IO macros
#include <cyg/hal/hal_intr.h>             // interrupt enable/disable
#include <cyg/infra/cyg_type.h>           // Common type definitions and support

#include <cyg/io/wallclock.hxx>           // The WallClock API
#include <cyg/io/ds1672.h>                // our header file

#include <cyg/infra/diag.h>



//
// This particular chip is always accessed via I2C (2-wire protocol)
// The platform needs to provide simple I2C access functions
//
// void DS_GET(cyg_uint8 *regs)
//    Reads the entire set of registers (8 bytes) into *regs
// void DS_PUT(cyg_uint8 *regs)
//    Updated the entire set of registers (8 bytes) from *regs
//
// Using this method, the data in the registers is guaranteed to be
// stable (if the access function manipulates the registers in an
// single operation)
//

// 
// Platform details
//
#include CYGDAT_DEVS_WALLCLOCK_DALLAS_1672_INL

//-----------------------------------------------------------------------------
// Accessor functions
//

//===========================================================================
//                      INITIALIZE DS1672 HARDWARE
// DESCRIPTTION:
//     Initialize the DS1672 hardware
//===========================================================================
static inline void init_ds_hwclock(void)
{
    cyg_uint8 regs[DS_REGS_SIZE];
    
    
    //
    // fetch the current state
    //
    DS_GET(regs);
    //
    // if oscillator is disabled in backup mode then enable osc
    //
    if (regs[DS_REG_CTRL] & DS_REG_CTRL_OSC_DIS)
    {
        regs[DS_REG_CTRL] = DS_REG_CTRL_OSC_EN;
    }
    //
    // update the current state
    //
    DS_PUT(regs);
}


//===========================================================================
//                        STORE TIME INTO DS1672  
// DESCRIPTION:
//     Set new time value
//
// ARGUMENTS:
//     'secs'   New seconds value to be set
//===========================================================================
static inline void set_ds_hwclock(cyg_uint32 secs)
{
    cyg_uint8  regs[DS_REGS_SIZE];
    
    
    //
    // fetch the current state
    //
    DS_GET(regs);
    regs[DS_REG_CNT_BYTE_1] = (cyg_uint8)(secs & 0xff);
    secs >>= 8;
    regs[DS_REG_CNT_BYTE_2] = (cyg_uint8)(secs & 0xff);
    secs >>= 8;
    regs[DS_REG_CNT_BYTE_3] = (cyg_uint8)(secs & 0xff);
    secs >>= 8;
    regs[DS_REG_CNT_BYTE_4] = (cyg_uint8)(secs & 0xff);
    //
    // update current state
    //
    DS_PUT(regs);
}


//===========================================================================
//                        GET TIMESTAMP FROM DS1672  
// DESCRIPTTION:
//     Returns the counted seconds
//
// RETURNS:
//     Number of counted seconds
//===========================================================================
static inline cyg_uint32 get_ds_hwclock(void)
{
    cyg_uint32 secs;
    cyg_uint8  regs[DS_REGS_SIZE];
    
    
    //
    // fetch the current state - reads lsb first
    //
    DS_GET(regs);
    secs =   regs[DS_REG_CNT_BYTE_4];
    secs <<= 8;
    secs +=  regs[DS_REG_CNT_BYTE_3];
    secs <<= 8;
    secs +=  regs[DS_REG_CNT_BYTE_2];
    secs <<= 8;
    secs +=  regs[DS_REG_CNT_BYTE_1];
    
    return secs;    
}


//===========================================================================
//                             GET SECONDS FROM HW
// DESCRIPTTION:
//     Returns the number of seconds elapsed since 1970-01-01 00:00:00.
//
// RETURNS:
//     Number of counted seconds
//===========================================================================
cyg_uint32 Cyg_WallClock::get_hw_seconds(void)
{
    return get_ds_hwclock();
}


#ifdef CYGSEM_WALLCLOCK_SET_GET_MODE
//===========================================================================
//                            STORE SECONDS INTO HW
// DESCRIPTTION:
//     Sets the clock.
//
// ARGUMENT:
//     'secs'   Seconds elapsed since 1970-01-01 00:00:00.
//===========================================================================
void Cyg_WallClock::set_hw_seconds(cyg_uint32 secs)
{
    set_ds_hwclock(secs);
}
#endif // CYGSEM_WALLCLOCK_SET_GET_MODE


//===========================================================================
//                            STORE SECONDS INTO HW
// DESCRIPTTION:
//     Sets the clock.
//
// ARGUMENT:
//     'secs'   Seconds elapsed since 1970-01-01 00:00:00.
//===========================================================================
void Cyg_WallClock::init_hw_seconds(void)
{
#ifdef CYGSEM_WALLCLOCK_SET_GET_MODE
    init_ds_hwclock();
#else
    // This is our base: 1970-01-01 00:00:00
    // Set the HW clock - if for nothing else, just to be sure it's in a
    // legal range. Any arbitrary base could be used.
    // After this the hardware clock is only read.
    set_ds_hwclock(0);
#endif
}

//-----------------------------------------------------------------------------
// End of devs/wallclock/ds1672.inl