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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 Free Software Foundation, 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.,    

// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 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   

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// must still be made available in accordance with section (3) of the GNU   

// General Public License v2.                                               

//

// This exception does not invalidate any other reasons why a work based    

// on this file might be covered by the GNU General Public License.         

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

// ####ECOSGPLCOPYRIGHTEND####                                              

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

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

//

// Author(s):    nickg

// Contributors: proven, pjo

// Date:        1999-02-20

// Purpose:     HAL miscellaneous functions

// Description: This file contains miscellaneous functions provided by the

//              HAL.

//

//####DESCRIPTIONEND####

//

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

#include <pkgconf/system.h>

#include <pkgconf/hal.h>

#include <cyg/infra/cyg_type.h>

#include <cyg/infra/cyg_ass.h>

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

#include <cyg/hal/hal_arch.h>

#include <cyg/hal/hal_intr.h>

#include <cyg/hal/hal_if.h>

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

#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;

#if defined(CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS)

externC void* volatile __mem_fault_handler;

#endif

void

cyg_hal_exception_handler(HAL_SavedRegisters *regs)

{

#if defined(CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS)

    // If we caught an exception inside the stubs, see if we were expecting it

    // and if so jump to the saved address

    if (__mem_fault_handler) {

        regs->pc = (CYG_ADDRWORD)__mem_fault_handler;

        return; // Caught an exception inside stubs        

    }

    _hal_registers = regs;

    __handle_exception();

#elif defined(CYGFUN_HAL_COMMON_KERNEL_SUPPORT) && defined(CYGPKG_HAL_EXCEPTIONS)

    // We should decode the vector and pass a more appropriate

    // value as the second argument. For now we simply pass a

    // pointer to the saved registers. We should also divert

    // breakpoint and other debug vectors into the debug stubs.

    cyg_hal_deliver_exception( regs->vector>>8, (CYG_ADDRWORD)regs );

#else

    CYG_FAIL("Exception!!!");

#endif    

    return;

}

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

/* default architecture ISR                                               */

/* The real default ISR is in hal/common/.../src/hal_misc.c               */

externC cyg_uint32 hal_arch_default_isr(CYG_ADDRWORD vector, CYG_ADDRWORD data)

{

    // For some reason I seem to be geting spurious interrupts on

    // interrupt 0x27(39). This is the parallel port. This is masked

    // in the PIC so the exact reason for these is a mystery. They do

    // appear to be real interrupts since they always appear just

    // after a clear of the interrupt flag, and the stack shows a

    // proper interrupt context being pushed by the hardware. This may

    // be some feature of the Celeron CPU I am using. 

    if( vector == 0x27 )

        return 2;

    diag_printf("hal_arch_default_isr: %d (data: %d)\n", vector,data);

    CYG_FAIL("Spurious Interrupt!!!");

    return 0;

}

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

// Profiling support. The timer has to be implemented by the platform

// HAL, but mcount() is generic for all x86 processors. There are three

// complications: the generic profile code assumes that __profile_mcount()

// is called with interrupts disabled; on an SMP system there may be

// concurrent calls to mcount(); and if eCos itself is built with

// -pg then there may be recursive calls to mcount() which we have

// to guard against.

//

// With i386-elf-gcc the call is to _mcount(), not mcount(), and there

// is already a return address in %edx. For now the latter is ignored.

// It would be useful in assembler code, but because we have to worry

// about interrupts and spinlocks a implementation is rather easier.

#ifdef CYGPKG_PROFILE_GPROF

#include <cyg/profile/profile.h>

# ifdef CYGPKG_HAL_SMP_SUPPORT

static HAL_SMP_CPU_TYPE     mcount_cpu  = HAL_SMP_CPU_NONE;

static HAL_SPINLOCK_TYPE    mcount_lock = HAL_SPINLOCK_INIT_CLEAR;

void

_mcount(void)

{

    int                 ints_enabled;

    HAL_SMP_CPU_TYPE    this_cpu;

    HAL_DISABLE_INTERRUPTS(ints_enabled);

    // This cpu is now not going to run any other code. So, did it

    // already own the spinlock?

    this_cpu = HAL_SMP_CPU_THIS();

    if (mcount_cpu != this_cpu) {

        // Nope, so this cannot be a nested call to mcount()

        HAL_SPINLOCK_SPIN(mcount_lock);

        // And no other cpu is executing inside mcount() either

        mcount_cpu  = this_cpu;

        // A possibly-recursive call is now safe.

        __profile_mcount((CYG_ADDRWORD)__builtin_return_address(1),

                         (CYG_ADDRWORD)__builtin_return_address(0));

        // All done.

        mcount_cpu = HAL_SMP_CPU_NONE;

        HAL_SPINLOCK_CLEAR(mcount_lock);

    }

    HAL_RESTORE_INTERRUPTS(ints_enabled);

}

# else   // ! SMP

static int  mcount_nested;

void

_mcount(void)

{

    int ints_enabled;

    HAL_DISABLE_INTERRUPTS(ints_enabled);

    if (! mcount_nested) {

        mcount_nested   = 1;

        __profile_mcount((CYG_ADDRWORD)__builtin_return_address(1),

                         (CYG_ADDRWORD)__builtin_return_address(0));

        mcount_nested   = 0;

    }

    HAL_RESTORE_INTERRUPTS(ints_enabled);

}

# endif // SMP

// The main VSR will update hal_saved_interrupt_state if profiling is

// enabled, on the assumption that the platform-specific

// hal_enable_profile_timer() will somehow make use of timer

// interrupts. The generic HAL will only provide that if GDB break

// support is enabled.

# if !( defined(CYGDBG_HAL_DEBUG_GDB_CTRLC_SUPPORT) || defined(CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT))

struct HAL_SavedRegisters *hal_saved_interrupt_state;

# endif

#endif  // CYGPKG_PROFILE_GPROF

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

// End of hal_misc.c