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#ifndef CYGONCE_HAL_HAL_ARCH_H

#define CYGONCE_HAL_HAL_ARCH_H

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

//

//      hal_arch.h

//

//      Architecture specific abstractions

//

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

//####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):    nickg,gthomas

// Contributors: nickg,jlarmour

// Date:         2001-03-21

// Purpose:      Define architecture abstractions

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

//              

//####DESCRIPTIONEND####

//

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

#include <pkgconf/hal.h>

#include <cyg/infra/cyg_type.h>

#include <cyg/hal/var_arch.h>

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

// Processor saved states:

#define CYG_HAL_NEC_REG CYG_WORD32

#define CYG_HAL_NEC_REG_SIZE 4

typedef struct

{

    // These are common to all saved states

    CYG_HAL_NEC_REG     d[32];          /* Data regs                    */

    CYG_ADDRWORD        pc;             /* Program Counter              */

    CYG_ADDRWORD        psw;            /* Status Reg                   */

    // These are only saved for exceptions and interrupts

    CYG_ADDRWORD        cause;          /* Exception cause register     */

    CYG_ADDRWORD        vector;         /* Exception/interrupt number   */

} HAL_SavedRegisters;

//

// Processor state register

//

#define CYGARC_PSW_ID   0x20     // Interrupt disable

#define CYGARC_PSW_EP   0x40     // Exception in progress

#define CYGARC_PSW_NP   0x80     // NMI in progress

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

// Exception handling function.

// This function is defined by the kernel according to this prototype. It is

// invoked from the HAL to deal with any CPU exceptions that the HAL does

// not want to deal with itself. It usually invokes the kernel's exception

// delivery mechanism.

externC void cyg_hal_deliver_exception( CYG_WORD code, CYG_ADDRWORD data );

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

// Bit manipulation macros

externC cyg_uint32 hal_lsbit_index(cyg_uint32 mask);

externC cyg_uint32 hal_msbit_index(cyg_uint32 mask);

#define HAL_LSBIT_INDEX(index, mask) index = hal_lsbit_index(mask);

#define HAL_MSBIT_INDEX(index, mask) index = hal_msbit_index(mask);

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

// Context Initialization

#define CYG_HAL_NEC_INIT_PSW  0x00000000

// Initialize the context of a thread.

// Arguments:

// _sparg_ 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_ )                     \

{                                                                                       \

    register CYG_WORD _sp_ = ((CYG_WORD)_sparg_)-56;                                    \

    register HAL_SavedRegisters *_regs_;                                                \

    int _i_;                                                                            \

    _sp_ = _sp_ & 0xFFFFFFF0;                                                           \

    _regs_ = (HAL_SavedRegisters *)(((_sp_) - sizeof(HAL_SavedRegisters))&0xFFFFFFF0);  \

    for( _i_ = 0; _i_ < 32; _i_++ ) (_regs_)->d[_i_] = (_id_)|_i_;                      \

    (_regs_)->d[03] = (CYG_HAL_NEC_REG)(_sp_);       /* SP = top of stack      */      \

    (_regs_)->d[04] = (CYG_HAL_NEC_REG)(_sp_);       /* GP = top of stack      */      \

    (_regs_)->d[29] = (CYG_HAL_NEC_REG)(_sp_);       /* FP = top of stack      */      \

    (_regs_)->d[06] = (CYG_HAL_NEC_REG)(_thread_);   /* R6 = arg1 = thread ptr */      \

    (_regs_)->d[31] = (CYG_HAL_NEC_REG)(_entry_);    /* RA(d[31]) = entry point*/      \

    (_regs_)->pc = (CYG_WORD)(_entry_);              /* PC = entry point       */      \

    (_regs_)->psw = CYG_HAL_NEC_INIT_PSW;                                              \

    _sparg_ = (CYG_ADDRESS)_regs_;                                                      \

}

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

// 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_ );

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

// Execution reorder barrier.

// When optimizing the compiler can reorder code. In multithreaded systems

// where the order of actions is vital, this can sometimes cause problems.

// This macro may be inserted into places where reordering should not happen.

// The "memory" keyword is potentially unnecessary, but it is harmless to

// keep it.

#define HAL_REORDER_BARRIER() asm volatile ( "" : : : "memory" )

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

// Breakpoint support

// HAL_BREAKPOINT() is a code sequence that will cause a breakpoint to

// happen if executed.

// HAL_BREAKINST is the value of the breakpoint instruction and

// HAL_BREAKINST_SIZE is its size in bytes.

#define HAL_BREAKPOINT(_label_)                 \

asm volatile (" .globl  _" #_label_ ";"         \

              "_"#_label_":"                    \

              " br _"#_label_                   \

    );

#define HAL_BREAKINST           0x0585

#define HAL_BREAKINST_SIZE      2

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

// Thread register state manipulation for GDB support.

// Default to a 32 bit register size for GDB register dumps.

#ifndef CYG_HAL_GDB_REG

#define CYG_HAL_GDB_REG CYG_WORD32

#endif

// Translate a stack pointer as saved by the thread context macros above into

// a pointer to a HAL_SavedRegisters structure.

#define HAL_THREAD_GET_SAVED_REGISTERS( _sp_, _regs_ )          \

        (_regs_) = (HAL_SavedRegisters *)(_sp_)

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

// HAL setjmp

typedef struct {

    cyg_uint32 sp;

    cyg_uint32 gp;

    cyg_uint32 tp;

    cyg_uint32 r1,r2,r4,r5;

    cyg_uint32 r20, r21, r22, r23;

    cyg_uint32 r24, r25, r26, r27, r28;

    cyg_uint32 fp;

    cyg_uint32 ep;

    cyg_uint32 lp;

} hal_jmp_buf_t;

#define CYGARC_JMP_BUF_SIZE      (sizeof(hal_jmp_buf_t) / sizeof(cyg_uint32))

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);

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

// Idle thread code.

// This macro is called in the idle thread loop, and gives the HAL the

// chance to insert code. Typical idle thread behaviour might be to halt the

// processor.

externC void hal_idle_thread_action(cyg_uint32 loop_count);

#define HAL_IDLE_THREAD_ACTION(_count_) hal_idle_thread_action(_count_)

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

// Hardware specific test exit code.  This is defined here simply to make

// setting a breakpoint on this function viable.

//

#define CYGHWR_TEST_PROGRAM_EXIT()              \

{                                               \

    static volatile int ctr;                    \

    while (1) ctr++;                            \

}

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

// 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.

// Typical case stack frame size: return link + 4 pushed registers + some locals.

#define CYGNUM_HAL_STACK_FRAME_SIZE (48)

// Stack needed for a context switch:

#define CYGNUM_HAL_STACK_CONTEXT_SIZE (((32+12)*CYG_HAL_NEC_REG_SIZE)+(32*4))

// Interrupt + call to ISR, interrupt_end() and the DSR

#define CYGNUM_HAL_STACK_INTERRUPT_SIZE (4+2*CYGNUM_HAL_STACK_CONTEXT_SIZE) 

#ifdef CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK

// An interrupt stack which is large enough for all possible interrupt

// conditions (and only used for that purpose) exists.  "User" stacks

// can be much smaller

#define CYGNUM_HAL_STACK_SIZE_MINIMUM (CYGNUM_HAL_STACK_CONTEXT_SIZE+      \

                                       CYGNUM_HAL_STACK_INTERRUPT_SIZE*2+  \

                                       CYGNUM_HAL_STACK_FRAME_SIZE*8)

#define CYGNUM_HAL_STACK_SIZE_TYPICAL (CYGNUM_HAL_STACK_SIZE_MINIMUM+1024)

#else // CYGIMP_HAL_COMMON_INTERRUPTS_USE_INTERRUPT_STACK 

// No separate interrupt stack exists.  Make sure all threads contain

// a stack sufficiently large.

#define CYGNUM_HAL_STACK_SIZE_MINIMUM (4096)

#define CYGNUM_HAL_STACK_SIZE_TYPICAL (4096)

#endif

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

// 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_HAL_ARCH_H

// End of hal_arch.h