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

//

//      hal_misc.c

//

//      HAL miscellaneous functions

//

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

//####ECOSGPLCOPYRIGHTBEGIN####

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

// This file is part of eCos, the Embedded Configurable Operating System.

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

//

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// for more details.

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//

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// 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

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//####ECOSGPLCOPYRIGHTEND####

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

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

//

// Author(s):    jskov

// Contributors: jskov, jlarmour, nickg

// Date:         1999-04-03

// 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>

#include <cyg/infra/cyg_trac.h>         // tracing macros

#include <cyg/infra/cyg_ass.h>          // assertion macros

#include <cyg/infra/diag.h>             // diag_printf

#include <cyg/hal/hal_arch.h>           // HAL header

#include <cyg/hal/hal_cache.h>          // HAL cache

#include <cyg/hal/hal_intr.h>           // HAL interrupts/exceptions

#include <cyg/hal/sh_regs.h>            // timer registers

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

// Functions used during initialization.

#ifdef CYGSEM_HAL_STOP_CONSTRUCTORS_ON_FLAG

cyg_bool cyg_hal_stop_constructors;

#endif

typedef void (*pfunc) (void);

extern pfunc __CTOR_LIST__[];

extern pfunc __CTOR_END__[];

void

cyg_hal_invoke_constructors (void)

{

#ifdef CYGSEM_HAL_STOP_CONSTRUCTORS_ON_FLAG

    static pfunc *p = &__CTOR_END__[-1];

    cyg_hal_stop_constructors = 0;

    for (; p >= __CTOR_LIST__; p--) {

        (*p) ();

        if (cyg_hal_stop_constructors) {

            p--;

            break;

        }

    }

#else

    pfunc *p;

    for (p = &__CTOR_END__[-1]; p >= __CTOR_LIST__; p--)

        (*p) ();

#endif

}

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

// First level C exception handler.

externC void __handle_exception (void);

externC HAL_SavedRegisters *_hal_registers;

#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS

externC void* volatile __mem_fault_handler;

#endif

void

cyg_hal_exception_handler(HAL_SavedRegisters *regs)

{

#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS

    if (__mem_fault_handler &&

        ((regs->event >= _CYGNUM_HAL_VECTOR_FIRST_MEM_FAULT) &&

         (regs->event <= _CYGNUM_HAL_VECTOR_LAST_MEM_FAULT))) {

        regs->pc = (unsigned long)__mem_fault_handler;

        return; // Caught an exception inside stubs        

    }

    // Set the pointer to the registers of the current exception

    // context. At entry the GDB stub will expand the

    // HAL_SavedRegisters structure into a (bigger) register array.

    _hal_registers = regs;

    __handle_exception();

#elif defined(CYGFUN_HAL_COMMON_KERNEL_SUPPORT) && \

      defined(CYGPKG_HAL_EXCEPTIONS)

    cyg_hal_deliver_exception( regs->event, (CYG_ADDRWORD)regs );

#else

    CYG_FAIL("Exception!!!");

#endif    

    return;

}

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

// Default ISR

externC cyg_uint32

hal_arch_default_isr(CYG_ADDRWORD vector, CYG_ADDRWORD data)

{

    return 0;

}

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

// Determine the index of the ls bit of the supplied mask.

cyg_uint32

hal_lsbit_index(cyg_uint32 mask)

{

    cyg_uint32 n = mask;

    static const signed char tab[64] =

    { -1, 0, 1, 12, 2, 6, 0, 13, 3, 0, 7, 0, 0, 0, 0, 14, 10,

      4, 0, 0, 8, 0, 0, 25, 0, 0, 0, 0, 0, 21, 27 , 15, 31, 11,

      5, 0, 0, 0, 0, 0, 9, 0, 0, 24, 0, 0 , 20, 26, 30, 0, 0, 0,

      0, 23, 0, 19, 29, 0, 22, 18, 28, 17, 16, 0

    };

    n &= ~(n-1UL);

    n = (n<<16)-n;

    n = (n<<6)+n;

    n = (n<<4)+n;

    return tab[n>>26];

}

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

// Determine the index of the ms bit of the supplied mask.

cyg_uint32

hal_msbit_index(cyg_uint32 mask)

{

    cyg_uint32 x = mask;

    cyg_uint32 w;

    // Phase 1: make word with all ones from that one to the right

    x |= x >> 16;

    x |= x >> 8;

    x |= x >> 4;

    x |= x >> 2;

    x |= x >> 1;

    // Phase 2: calculate number of "1" bits in the word

    w = (x & 0x55555555) + ((x >> 1) & 0x55555555);

    w = (w & 0x33333333) + ((w >> 2) & 0x33333333);

    w = w + (w >> 4);

    w = (w & 0x000F000F) + ((w >> 8) & 0x000F000F);

    return (cyg_uint32)((w + (w >> 16)) & 0xFF) - 1;

}

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

// Idle thread action

void

hal_idle_thread_action( cyg_uint32 count )

{

}

#ifdef CYGHWR_SH_RTC_TIMER_IS_TMU

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

// Low-level delay (in microseconds)

void

hal_delay_us(int usecs)

{

    unsigned char _tstr;  // Current clock control

    volatile unsigned char *tstr = (volatile unsigned char *)CYGARC_REG_TSTR;

    volatile unsigned long *tcnt = (volatile unsigned long *)CYGARC_REG_TCNT1;

    volatile unsigned long *tcor = (volatile unsigned long *)CYGARC_REG_TCOR1;

    unsigned long clocks_per_us = (CYGHWR_HAL_SH_ONCHIP_PERIPHERAL_SPEED+(CYGHWR_HAL_SH_TMU_PRESCALE_0-1))/CYGHWR_HAL_SH_TMU_PRESCALE_0;  // Rounded up

    int diff, diff2;

    cyg_uint32 val1, val2;

    _tstr = *tstr;

    *tstr |= CYGARC_REG_TSTR_STR1;  // Enable channel 1

    while (usecs-- > 0) {

        diff = 0;

        while (diff < clocks_per_us) {

            val1 = *tcnt;

            while ((val2 = *tcnt) == val1) ;

            diff2 = val2 - val1;

            if (diff2 < 0) diff2 += *tcor;

            diff += diff2;

        }

    }

    *tstr = _tstr;                  // Restore timer to previous state

}

#endif

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

// End of hal_misc.c