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#ifndef CYGONCE_HAL_VAR_ARCH_H

#define CYGONCE_HAL_VAR_ARCH_H

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

//

//      var_arch.h

//

//      Per-processor information such as processor save states.

//

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

//####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):   proven

// Contributors:proven, pjo, nickg,bartv

// Date:        1998-10-05

// Purpose:     Define architecture abstractions

// Usage:       #include <cyg/hal/hal_arch.h>

//

//####DESCRIPTIONEND####

//

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

#include <cyg/infra/cyg_type.h>

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

// Processor saved states. This structure is also defined in arch.inc for

// assembly code. Do not change this without changing that (or vice versa).

// Note: there is no need to worry about floating point contexts, see context.S

typedef struct

{

    cyg_uint32  esp;

    cyg_uint32  next_context;           // only used when dropping through...

    cyg_uint32  ebp;                    // ...from switch_ to load_context

    cyg_uint32  ebx;

    cyg_uint32  esi;

    cyg_uint32  edi;

    cyg_bool    interrupts;             // Are interrupts enabled for this thread?

} HAL_SavedRegisters;

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

// Bit manipulation routines. These are provided by the processor variant

// HAL to allow for processor-specific implementations.

#define HAL_LSBIT_INDEX(index, mask)            \

CYG_MACRO_START                                 \

    asm volatile( "bsfl %1,%0\n"                \

                  : "=r" (index)                \

                  : "r" (mask)                  \

                );                              \

CYG_MACRO_END

#define HAL_MSBIT_INDEX(index, mask)            \

CYG_MACRO_START                                 \

    asm volatile( "bsrl %1,%0\n"                \

                  : "=r" (index)                \

                  : "r" (mask)                  \

                );                              \

CYG_MACRO_END

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

// Context Initialization

// Initialize the context of a thread.

// Arguments:

// _sp_ name of variable containing current sp, will be written with new sp

// _thread_ thread object address, passed as argument to entry point

// _entry_ entry point address.

// _id_ bit pattern used in initializing registers, for debugging.

#define HAL_THREAD_INIT_CONTEXT( _sparg_, _thread_, _entry_, _id_ )       \

    CYG_MACRO_START                                                       \

    register CYG_WORD* _sp_ = ((CYG_WORD*)((_sparg_) &~15));              \

    register HAL_SavedRegisters *_regs_;                                  \

                                                                          \

    /* The 'ret' executed at the end of hal_thread_load_context will  */  \

    /* use the last entry on the stack as a return pointer (_entry_). */  \

    /* Cyg_HardwareThread::thread_entry expects one argument at stack */  \

    /* offset 4 (_thread_). The (0xDEADBEEF) entry is the return addr */  \

    /* for thread_entry (which is never used).                        */  \

    *(--_sp_) = (CYG_WORD)(0);                                            \

    *(--_sp_) = (CYG_WORD)(0);                                            \

    *(--_sp_) = (CYG_WORD)(0);                                            \

    *(--_sp_) = (CYG_WORD)(0);                                            \

    *(--_sp_) = (CYG_WORD)(_thread_);                                     \

    *(--_sp_) = (CYG_WORD)(0);                                            \

    *(--_sp_) = (CYG_WORD)(_entry_);                                      \

                                                                          \

    _regs_ = (HAL_SavedRegisters *)                                       \

               ((unsigned long)_sp_ - sizeof(HAL_SavedRegisters));        \

    _regs_->esp    = (CYG_WORD) _sp_;                                     \

    _regs_->ebx    = (CYG_WORD)(_id_);                                    \

    _regs_->ebp    = (CYG_WORD)(_id_);                                    \

    _regs_->esi    = (CYG_WORD)(_id_);                                    \

    _regs_->edi    = (CYG_WORD)(_id_);                                    \

    _regs_->interrupts = true;                                            \

    (_sparg_)      = (CYG_ADDRESS) _regs_;                                \

    CYG_MACRO_END

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

// Context switch macros.

// The arguments are pointers to locations where the stack pointer

// of the current thread is to be stored, and from where the sp of the

// next thread is to be fetched.

externC void hal_thread_switch_context( CYG_ADDRESS _to_, CYG_ADDRESS _from_ );

externC void hal_thread_load_context( CYG_ADDRESS _to_ )

    __attribute__ ((noreturn));

#define HAL_THREAD_SWITCH_CONTEXT(_fspptr_,_tspptr_)                    \

        hal_thread_switch_context((CYG_ADDRESS)_tspptr_,(CYG_ADDRESS)_fspptr_);

#define HAL_THREAD_LOAD_CONTEXT(_tspptr_)                               \

        hal_thread_load_context( (CYG_ADDRESS)_tspptr_ );

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

// HAL setjmp

#define CYGARC_JMP_BUF_SP        0

#define CYGARC_JMP_BUF_EBP       1

#define CYGARC_JMP_BUF_EBX       2

#define CYGARC_JMP_BUF_ESI       3

#define CYGARC_JMP_BUF_EDI       4

#define CYGARC_JMP_BUF_PC        5

#define CYGARC_JMP_BUF_SIZE      6

typedef cyg_uint32 hal_jmp_buf[CYGARC_JMP_BUF_SIZE];

externC int hal_setjmp(hal_jmp_buf env);

externC void hal_longjmp(hal_jmp_buf env, int val);

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

// Minimal and sensible stack sizes: the intention is that applications

// will use these to provide a stack size in the first instance prior to

// proper analysis.  Idle thread stack should be this big.

//    THESE ARE NOT INTENDED TO BE MICROMETRICALLY ACCURATE FIGURES.

//           THEY ARE HOWEVER ENOUGH TO START PROGRAMMING.

// YOU MUST MAKE YOUR STACKS LARGER IF YOU HAVE LARGE "AUTO" VARIABLES!

// This is not a config option because it should not be adjusted except

// under "enough rope" sort of disclaimers.

// Stack frame overhead per call. 3 local registers (edi, esi, ebx) and

// return address.

#define CYGNUM_HAL_STACK_FRAME_SIZE (4 * 4)

// Stack needed for a context switch (i386reg_context_size from i386.inc)

#define CYGNUM_HAL_STACK_CONTEXT_SIZE (4 * 24)

// Interrupt stack size. Interrupts are handled by signals so the relevant

// data is MINSIGSTKSIZE (see man sigaltstack) or 2048. Given the

// multiplier *15 for STACK_SIZE_MINIMUM, this should be adequate.

#define CYGNUM_HAL_STACK_INTERRUPT_SIZE 2048

// We define a minimum stack size as the minimum any thread could ever

// legitimately get away with. We can throw asserts if users ask for less

// than this. Allow enough for three interrupt sources - clock, serial and

// one other

//

// On the synthetic target memory is cheap so comparatively large stacks

// are possible. This avoids stack overflow problems when working with

// the synthetic target, although arguably the problem is now deferred to

// when the application is moved to real hardware where it will be more

// difficult to track down.

#define CYGNUM_HAL_STACK_SIZE_MINIMUM (16 * 1024)

#define CYGNUM_HAL_STACK_SIZE_TYPICAL (32 * 1024)

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

// Macros for switching context between two eCos instances (jump from

// code in ROM to code in RAM or vice versa).

#define CYGARC_HAL_SAVE_GP()

#define CYGARC_HAL_RESTORE_GP()

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

#endif // CYGONCE_HAL_VAR_ARCH_H

// End of var_arch.h