hal_stub.c

eCos操作系统源码

void 
initHardware (void) 
{
    static int initialized = 0;

    if (initialized)
        return;
    initialized = 1;

    // Get serial port initialized.
    HAL_STUB_PLATFORM_INIT_SERIAL();

#ifdef HAL_STUB_PLATFORM_INIT
    // If the platform defines any initialization code, call it here.
    HAL_STUB_PLATFORM_INIT();
#endif        

#ifndef CYGSEM_HAL_VIRTUAL_VECTOR_SUPPORT // this should go away
#ifdef CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT
    // Get interrupt handler initialized.
    HAL_STUB_PLATFORM_INIT_BREAK_IRQ();
#endif
#endif // !CYGSEM_HAL_VIRTUAL_VECTOR_SUPPORT
}

// Reset the board.
void 
__reset (void)
{
#ifdef CYGSEM_HAL_VIRTUAL_VECTOR_SUPPORT
    __call_if_reset_t *__rom_reset = CYGACC_CALL_IF_RESET_GET();
    if (__rom_reset)
        (*__rom_reset)();
#else
    HAL_PLATFORM_RESET();
#endif
}

//-----------------------------------------------------------------------------
// Breakpoint support.

#ifndef CYGPKG_HAL_ARM
// This function will generate a breakpoint exception.  It is used at
// the beginning of a program to sync up with a debugger and can be
// used otherwise as a quick means to stop program execution and
// "break" into the debugger.
void
breakpoint()
{
    HAL_BREAKPOINT(_breakinst);
}

// This function returns the opcode for a 'trap' instruction.
unsigned long 
__break_opcode ()
{
  return HAL_BREAKINST;
}
#endif

//-----------------------------------------------------------------------------
// Write the 'T' packet in BUFFER. SIGVAL is the signal the program received.
void 
__build_t_packet (int sigval, char *buf)
{
    target_register_t addr;
    char *ptr = buf;
    target_register_t extend_val = 0;

    *ptr++ = 'T';
    *ptr++ = __tohex (sigval >> 4);
    *ptr++ = __tohex (sigval);

#ifdef CYGDBG_HAL_DEBUG_GDB_THREAD_SUPPORT
    // Include thread ID if thread manipulation is required.
    {
        int id = dbg_currthread_id ();

        if (id != 0) {
	    *ptr++ = 't';
	    *ptr++ = 'h';
	    *ptr++ = 'r';
	    *ptr++ = 'e';
	    *ptr++ = 'a';
	    *ptr++ = 'd';
	    *ptr++ = ':';

#if (CYG_BYTEORDER == CYG_LSBFIRST)
	    // FIXME: Temporary workaround for PR 18903. Thread ID must be
	    // big-endian in the T packet.
	    {
		unsigned char* bep = (unsigned char*)&id;
		int be_id;

		be_id = id;
		*bep++ = (be_id >> 24) & 0xff ;
		*bep++ = (be_id >> 16) & 0xff ;
		*bep++ = (be_id >> 8) & 0xff ;
		*bep++ = (be_id & 0xff) ;
	    }
#endif
	    ptr = __mem2hex((char *)&id, ptr, sizeof(id), 0);
	    *ptr++ = ';';
	}
    }
#endif

#ifdef HAL_STUB_HW_WATCHPOINT
    switch(_hw_stop_reason) {
      case HAL_STUB_HW_STOP_WATCH:
      case HAL_STUB_HW_STOP_RWATCH:
      case HAL_STUB_HW_STOP_AWATCH:
#ifdef HAL_STUB_HW_SEND_STOP_REASON_TEXT
        // Not all GDBs understand this.
	strcpy(ptr, _hw_stop_str[_hw_stop_reason]);
	ptr += strlen(_hw_stop_str[_hw_stop_reason]);
#endif
	*ptr++ = ':';
	// Send address MSB first
	ptr += __intToHex(ptr, (target_register_t)_watch_data_addr,
			  sizeof(_watch_data_addr) * 8);
	*ptr++ = ';';
	break;
      default:
	break;
    }
#endif

    *ptr++ = __tohex (PC >> 4);
    *ptr++ = __tohex (PC);
    *ptr++ = ':';
    addr = get_register (PC);
    if (sizeof(addr) < REGSIZE(PC))
    {
        // GDB is expecting REGSIZE(PC) number of bytes.
        // We only have sizeof(addr) number.  Let's fill
        // the appropriate number of bytes intelligently.
#ifdef CYGARC_SIGN_EXTEND_REGISTERS
        {
            unsigned long bits_in_addr = (sizeof(addr) << 3);  // ie Size in bytes * 8
            target_register_t sign_bit_mask = (1 << (bits_in_addr - 1));
            if ((addr & sign_bit_mask) == sign_bit_mask)
                extend_val = ~0;
        }
#endif
    }
#if (CYG_BYTEORDER == CYG_MSBFIRST)
    ptr = __mem2hex((char *)&extend_val, ptr, REGSIZE(PC) - sizeof(addr), 0);
#endif
    ptr = __mem2hex((char *)&addr, ptr, sizeof(addr), 0);
#if (CYG_BYTEORDER == CYG_LSBFIRST)
    ptr = __mem2hex((char *)&extend_val, ptr, REGSIZE(PC) - sizeof(addr), 0);
#endif
    *ptr++ = ';';

    *ptr++ = __tohex (SP >> 4);
    *ptr++ = __tohex (SP);
    *ptr++ = ':';
    addr = (target_register_t) get_register (SP);
    if (sizeof(addr) < REGSIZE(SP))
    {
        // GDB is expecting REGSIZE(SP) number of bytes.
        // We only have sizeof(addr) number.  Let's fill
        // the appropriate number of bytes intelligently.
        extend_val = 0;
#ifdef CYGARC_SIGN_EXTEND_REGISTERS
        {
            unsigned long bits_in_addr = (sizeof(addr) << 3);  // ie Size in bytes * 8
            target_register_t sign_bit_mask = (1 << (bits_in_addr - 1));
            if ((addr & sign_bit_mask) == sign_bit_mask)
                extend_val = ~0;
        }
#endif
        ptr = __mem2hex((char *)&extend_val, ptr, REGSIZE(SP) - sizeof(addr), 0);
    }
    ptr = __mem2hex((char *)&addr, ptr, sizeof(addr), 0);
    *ptr++ = ';';

    HAL_STUB_ARCH_T_PACKET_EXTRAS(ptr);
    
    *ptr++ = 0;
}


//-----------------------------------------------------------------------------
// Cache functions.

// Perform the specified operation on the instruction cache. 
// Returns 1 if the cache is enabled, 0 otherwise.
int 
__instruction_cache (cache_control_t request)
{
    int state = 1;

    switch (request) {
    case CACHE_ENABLE:
        HAL_ICACHE_ENABLE();
        break;
    case CACHE_DISABLE:
        HAL_ICACHE_DISABLE();
        state = 0;
        break;
    case CACHE_FLUSH:
        HAL_ICACHE_SYNC();
        break;
    case CACHE_NOOP:
        /* fall through */
    default:
        break;
    }

#ifdef HAL_ICACHE_IS_ENABLED
    HAL_ICACHE_IS_ENABLED(state);
#endif

    return state;
}

// Perform the specified operation on the data cache. 
// Returns 1 if the cache is enabled, 0 otherwise.
int 
__data_cache (cache_control_t request)
{
    int state = 1;

    switch (request) {
    case CACHE_ENABLE:
        HAL_DCACHE_ENABLE();
        break;
    case CACHE_DISABLE:
        HAL_DCACHE_DISABLE();
        state = 0;
        break;
    case CACHE_FLUSH:
        HAL_DCACHE_SYNC();
        break;
    case CACHE_NOOP:
        /* fall through */
    default:
        break;
    }
#ifdef HAL_DCACHE_IS_ENABLED
    HAL_DCACHE_IS_ENABLED(state);
#endif

    return state;
}

//-----------------------------------------------------------------------------
// Memory accessor functions.

// The __mem_fault_handler pointer is volatile since it is only
// set/cleared by the function below - which does not rely on any
// other functions, so the compiler may decide to not bother updating
// the pointer at all. If any of the memory accesses cause an
// exception, the pointer must be set to ensure the exception handler
// can make use of it.

void* volatile __mem_fault_handler = (void *)0;

/* These are the "arguments" to __do_read_mem and __do_write_mem, 
   which are passed as globals to avoid squeezing them thru
   __set_mem_fault_trap.  */

static volatile target_register_t memCount;

static void
__do_copy_mem (unsigned char* src, unsigned char* dst)
{
    unsigned long *long_dst;
    unsigned long *long_src;
    unsigned short *short_dst;
    unsigned short *short_src;

    // Zero memCount is not really an error, but the goto is necessary to
    // keep some compilers from reordering stuff across the 'err' label.
    if (memCount == 0) goto err;

    __mem_fault = 1;                      /* Defaults to 'fail'. Is cleared */
                                          /* when the copy loop completes.  */
    __mem_fault_handler = &&err;

    // See if it's safe to do multi-byte, aligned operations
    while (memCount) {
        if ((memCount >= sizeof(long)) &&
            (((target_register_t)dst & (sizeof(long)-1)) == 0) &&
            (((target_register_t)src & (sizeof(long)-1)) == 0)) {
        
            long_dst = (unsigned long *)dst;
            long_src = (unsigned long *)src;

            *long_dst++ = *long_src++;
            memCount -= sizeof(long);

            dst = (unsigned char *)long_dst;
            src = (unsigned char *)long_src;
        } else if ((memCount >= sizeof(short)) &&
                   (((target_register_t)dst & (sizeof(short)-1)) == 0) &&
                   (((target_register_t)src & (sizeof(short)-1)) == 0)) {
            
            short_dst = (unsigned short *)dst;
            short_src = (unsigned short *)src;

            *short_dst++ = *short_src++;
            memCount -= sizeof(short);

            dst = (unsigned char *)short_dst;
            src = (unsigned char *)short_src;
        } else {
            *dst++ = *src++;
            memCount--;
        }
    }

    __mem_fault = 0;

 err:
    __mem_fault_handler = (void *)0;
}

/*
 * __read_mem_safe:
 * Get contents of target memory, abort on error.
 */

int
__read_mem_safe (void *dst, void *src, int count)
{
  if( !CYG_HAL_STUB_PERMIT_DATA_READ( src, count ) )
    return 0;

  memCount = count;
  __do_copy_mem((unsigned char*) src, (unsigned char*) dst);
  return count - memCount;      // return number of bytes successfully read
}

/*
 * __write_mem_safe:
 * Set contents of target memory, abort on error.
 */

int
__write_mem_safe (void *src, void *dst, int count)
{
  if( !CYG_HAL_STUB_PERMIT_DATA_READ( dst, count ) )
    return 0;

  memCount = count;
  __do_copy_mem((unsigned char*) src, (unsigned char*) dst);
  return count - memCount;      // return number of bytes successfully written
}

#ifdef TARGET_HAS_HARVARD_MEMORY
static void
__do_copy_from_progmem (unsigned char* src, unsigned char* dst)
{
    unsigned long *long_dst;
    unsigned long *long_src;
    unsigned short *short_dst;
    unsigned short *short_src;

    // Zero memCount is not really an error, but the goto is necessary to
    // keep some compilers from reordering stuff across the 'err' label.
    if (memCount == 0) goto err;

    __mem_fault = 1;                      /* Defaults to 'fail'. Is cleared */
                                          /* when the copy loop completes.  */
    __mem_fault_handler = &&err;

    // See if it's safe to do multi-byte, aligned operations
    while (memCount) {
        if ((memCount >= sizeof(long)) &&
            (((target_register_t)dst & (sizeof(long)-1)) == 0) &&
            (((target_register_t)src & (sizeof(long)-1)) == 0)) {
        
            long_dst = (unsigned long *)dst;
            long_src = (unsigned long *)src;

            *long_dst++ = __read_prog_uint32(long_src++);
            memCount -= sizeof(long);

            dst = (unsigned char *)long_dst;
            src = (unsigned char *)long_src;
        } else if ((memCount >= sizeof(short)) &&
                   (((target_register_t)dst & (sizeof(short)-1)) == 0) &&
                   (((target_register_t)src & (sizeof(short)-1)) == 0)) {
            
            short_dst = (unsigned short *)dst;
            short_src = (unsigned short *)src;

            *short_dst++ = __read_prog_uint16(short_src++);
            memCount -= sizeof(short);

            dst = (unsigned char *)short_dst;
            src = (unsigned char *)short_src;
        } else {
            *dst++ = __read_prog_uint8(src++);
            memCount--;
        }
    }

    __mem_fault = 0;

 err:
    __mem_fault_handler = (void *)0;
}

static void
__do_copy_to_progmem (unsigned char* src, unsigned char* dst)
{
    unsigned long *long_dst;
    unsigned long *long_src;
    unsigned short *short_dst;
    unsigned short *short_src;

    // Zero memCount is not really an error, but the goto is necessary to
    // keep some compilers from reordering stuff across the 'err' label.
    if (memCount == 0)	goto err;

    __mem_fault = 1;                      /* Defaults to 'fail'. Is cleared */
                                          /* when the copy loop completes.  */
    __mem_fault_handler = &&err;

    // See if it's safe to do multi-byte, aligned operations
    while (memCount) {
        if ((memCount >= sizeof(long)) &&
            (((target_register_t)dst & (sizeof(long)-1)) == 0) &&
            (((target_register_t)src & (sizeof(long)-1)) == 0)) {
        
            long_dst = (unsigned long *)dst;
            long_src = (unsigned long *)src;

            __write_prog_uint32(long_dst++, *long_src++);
            memCount -= sizeof(long);

            dst = (unsigned char *)long_dst;
            src = (unsigned char *)long_src;
        } else if ((memCount >= sizeof(short)) &&
                   (((target_register_t)dst & (sizeof(short)-1)) == 0) &&
                   (((target_register_t)src & (sizeof(short)-1)) == 0)) {
            
            short_dst = (unsigned short *)dst;
            short_src = (unsigned short *)src;

            __write_prog_uint16(short_dst++, *short_src++);
            memCount -= sizeof(short);

            dst = (unsigned char *)short_dst;
            src = (unsigned char *)short_src;
        } else {
            __write_prog_uint8(dst++, *src++);
            memCount--;
        }
    }

    __mem_fault = 0;

 err:
    __mem_fault_handler = (void *)0;
}

/*
 * __read_progmem_safe:
 * Get contents of target memory, abort on error.
 */

int
__read_progmem_safe (void *dst, void *src, int count)
{
  if( !CYG_HAL_STUB_PERMIT_CODE_READ( src, count ) )
    return 0;

  memCount = count;
  __do_copy_from_progmem((unsigned char*) src, (unsigned char*) dst);
  return count - memCount;      // return number of bytes successfully read
}

/*
 * __write_progmem_safe:
 * Set contents of target memory, abort on error.
 */

int
__write_progmem_safe (void *src, void *dst, int count)
{
  if( !CYG_HAL_STUB_PERMIT_CODE_WRITE( dst, count ) )
    return 0;

  memCount = count;
  __do_copy_to_progmem((unsigned char*) src, (unsigned char*) dst);
  return count - memCount;      // return number of bytes successfully written
}
#endif

//-----------------------------------------------------------------------------
// Target extras?!
int 
__process_target_query(char * pkt, char * out, int maxOut)
{ return 0 ; }
int 
__process_target_set(char * pkt, char * out, int maxout)
{ return 0 ; }
int 
__process_target_packet(char * pkt, char * out, int maxout)
{ return 0 ; }

// GDB string output, making sure interrupts are disabled.
// This function gets used by some diag output functions.
void 
hal_output_gdb_string(target_register_t str, int string_len)
{
    unsigned long __state;
    HAL_DISABLE_INTERRUPTS(__state);
    __output_gdb_string(str, string_len);
    HAL_RESTORE_INTERRUPTS(__state);
}

#endif // CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS