hal_arch.h

eCos操作系统源码

#ifndef CYGONCE_HAL_ARCH_H
#define CYGONCE_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, hmt
// Contributors: nickg, gthomas, hmt
// Date:         1999-02-20
// Purpose:      Define architecture abstractions
// Usage:        #include <cyg/hal/hal_arch.h>
// 
//####DESCRIPTIONEND####
//
//==========================================================================

#include <pkgconf/hal.h>
#include <pkgconf/hal_sparc.h>

#include <cyg/infra/cyg_type.h>

#include <cyg/hal/hal_intr.h>           // HAL_DISABLE_INTERRUPTS

//--------------------------------------------------------------------------
// Processor saved states:
//
// All these structures must be doubleword (64 bit) aligned.
// The code that creates them on the stack will ensure this is so.

#define HAL_THREAD_CONTEXT_GLOBAL_BASE 0
#define HAL_THREAD_CONTEXT_OUT_BASE    8
#define HAL_THREAD_CONTEXT_LOCAL_BASE 16
#define HAL_THREAD_CONTEXT_IN_BASE    24

typedef struct 
{
    // this is the save structure found at *(stack_ptr) always, note that
    // i[6] is the frame pointer is the previous stack pointer, and
    // o[6] is the stack pointer is the next frame pointer,
    // so they form a linked list back up the call stack.
    cyg_uint32  l[8];                                   /* Locals r16-r23 */
    cyg_uint32  i[8];                                   /* Ins    r24-r31 */
} HAL_SavedWindow;

typedef struct 
{
    // Window save at stack pointer
    HAL_SavedWindow li;
//16
    // This is the rest of the save state:
    //   NOTE: g[0] is used for the CWP, for %g0 == 0.  Also note that the
    //   assembler routines must load/store it in the right order.
    cyg_uint32  g[8] ;                                  /* Globals r0- r7 */
    cyg_uint32  o[8] ;                                  /* Outs    r8-r15 */
//32 words in size

// There is no need to save any other state; for example, condition codes,
// the PC and NextPC, and Y, are preserved in local registers in the trap
// handling window and so preserved in the caller stack frame as viewed
// from an ISR.  Note that the VSR is jumped to with those locals being set
// up (and Y in situ), and it must preserve them itself before calling any
// subsequent handlers (ISRs).

} HAL_SavedRegisters;


typedef struct 
{
    // Window save at stack pointer
    HAL_SavedWindow li;
    cyg_uint32      composite_return_ptr;          /* structure returns */
    cyg_uint32      spill_args[6];                 /* for callee to store */
    cyg_uint32      spare;                         /* keep this 64-bits   */
} HAL_FrameStructure;


//--------------------------------------------------------------------------
// 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
#ifndef CYGPKG_HAL_SPARC_SCAN
/* Most sparc's does not have 'scan' instruction */
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);
#else
#define HAL_LSBIT_INDEX(index, mask)            \
    CYG_MACRO_START                             \
    asm volatile (                              \
        "scan   %1, 0, %%l7;"                   \
        "mov    31, %0;"                        \
        "sub    %0, %%l7, %0"                   \
        : "=r"(index)                           \
        : "r"(mask & ~(mask-1))                 \
        : "l7"                                  \
        );                                      \
CYG_MACRO_END

#define HAL_MSBIT_INDEX(index, mask)            \
    CYG_MACRO_START                             \
    asm volatile (                              \
        "scan   %1, 0, %%l7;"                   \
        "mov    31, %0;"                        \
        "sub    %0, %%l7, %0"                   \
        : "=r"(index)                           \
        : "r"(mask)                             \
        : "l7"                                  \
        );                                      \
CYG_MACRO_END
#endif

//--------------------------------------------------------------------------
// Context Initialization
// 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.

externC CYG_ADDRESS
hal_thread_init_context(  CYG_WORD sparg,
                          CYG_WORD thread,
                          CYG_WORD entry,
                          CYG_WORD id ); 

#define HAL_THREAD_INIT_CONTEXT( _sparg_, _thread_, _entry_, _id_ )         \
CYG_MACRO_START                                                             \
    _sparg_ = hal_thread_init_context( (CYG_WORD)(_sparg_),                 \
                                       (CYG_WORD)(_thread_),                \
                                       (CYG_WORD)(_entry_),                 \
                                       (CYG_WORD)(_id_) );                  \
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.