plf_misc.c

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//==========================================================================
//
//      plf_misc.c
//
//      HAL platform miscellaneous functions
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// 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):    ysayo
// Contributors: ysato
// Date:         2002-08-10
// Purpose:      HAL miscellaneous functions
// Description:  This file contains miscellaneous functions provided by the
//               HAL.
//
//####DESCRIPTIONEND####
//
//========================================================================*/

#include <pkgconf/hal.h>

#include <cyg/infra/cyg_type.h>         // Base types

#include <cyg/hal/hal_arch.h>           // architectural definitions
#include <cyg/hal/hal_io.h>
#include <cyg/hal/hal_if.h>
#include <cyg/hal/plf_intr.h>
#include <cyg/hal/var_arch.h>

/*------------------------------------------------------------------------*/

void hal_platform_init(void)
{
    hal_if_init();
}

void h8300h_reset(void)
{
    __asm__ ("ldc #0x80,ccr\n"
             "jmp @@0\n\t");
}

/*------------------------------------------------------------------------*/
/* Control C ISR support                                                  */

#if defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT)

struct Hal_SavedRegisters *hal_saved_interrupt_state;

#endif

/*------------------------------------------------------------------------*/
/* clock support                                                            */

void hal_clock_initialize(cyg_uint32 period)
{
    CYG_BYTE prescale;
#if CYGNUM_HAL_H8300_RTC_PRESCALE == 8
    prescale = 0x01;
#else
#if CYGNUM_HAL_H8300_RTC_PRESCALE == 64
    prescale = 0x02;
#else
#if CYGNUM_HAL_H8300_RTC_PRESCALE == 8192
    prescale = 0x03;
#else
#error illigal RTC prescale setting
#endif
#endif
#endif
    HAL_WRITE_UINT8(CYGARC_TCORA3,period);
    HAL_WRITE_UINT8(CYGARC_8TCNT3,0x00);
    HAL_WRITE_UINT8(CYGARC_8TCR3,0x48 | prescale);
    HAL_WRITE_UINT8(CYGARC_8TCSR3,0x00);
}

void hal_clock_reset(cyg_uint32 vector, cyg_uint32 period)
{
    HAL_WRITE_UINT8(CYGARC_8TCR3,0x00);
    HAL_WRITE_UINT8(CYGARC_8TCSR3,0x00);
    hal_clock_initialize(period);
}

void hal_clock_read(cyg_uint32 *pvalue)
{
    CYG_BYTE val;
    HAL_READ_UINT8(CYGARC_8TCNT3,val);
    *pvalue = val;
}

//---------------------------------------------------------------------------
// Low-level delay (in microseconds)

#if 0
void hal_delay_us(int usecs)
{
    volatile CYG_BYTE *tcr  = (CYG_BYTE *)CYGARC_8TCR2;
    volatile CYG_BYTE *tcnt = (CYG_BYTE *)CYGARC_8TCNT2;
    short clocks_per_us = (CYGHWR_HAL_H8300_PROCESSOR_SPEED/1000000)/8*25;
    //short clocks_per_us = (CYGHWR_HAL_H8300_PROCESSOR_SPEED/1000000)/20;
    unsigned char val1,val2;
    short diff;

    usecs /= 25;

    *tcnt = 0x00;
    *tcr  = 0x01;
    
    diff = 0;
    while (usecs > 0) {
	while (diff < clocks_per_us) {
            val1 = *tcnt;
	    while ((val2 = *tcnt) == val1);
	    if (val2 < val1)
	        diff += val2 + 0x100 - val1;
	    else
		diff += val2 - val1;
	}
	usecs -= diff / clocks_per_us;
	diff -= clocks_per_us;
    }
    *tcr  = 0x00;
}
#endif

/*------------------------------------------------------------------------*/
/* End of plf_misc.c                                                      */