//==========================================================================////      flash_unlock_block.c////      Flash programming////==========================================================================//####ECOSGPLCOPYRIGHTBEGIN####// -------------------------------------------// This file is part of eCos, the Embedded Configurable Operating System.// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2004 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):    gthomas, hmt// Contributors: gthomas// Date:         2001-02-14// Purpose:      // Description:  //              //####DESCRIPTIONEND####////==========================================================================#include "strata.h"#include <cyg/hal/hal_cache.h>//// CAUTION!  This code must be copied to RAM before execution.  Therefore,// it must not contain any code which might be position dependent!////// The difficulty with this operation is that the hardware does not support// unlocking single blocks.  However, the logical layer would like this to// be the case, so this routine emulates it.  The hardware can clear all of// the locks in the device at once.  This routine will use that approach and// then reset the regions which are known to be locked.//#define MAX_FLASH_BLOCKS 128intflash_unlock_block(volatile flash_t *block, int block_size, int blocks){    volatile flash_t *ROM;    flash_t stat;    int timeout = 5000000;    int cache_on;#ifndef CYGOPT_FLASH_IS_SYNCHRONOUS    int i;    volatile flash_t *bp, *bpv;    unsigned char is_locked[MAX_FLASH_BLOCKS];#endif    HAL_DCACHE_IS_ENABLED(cache_on);    if (cache_on) {        HAL_DCACHE_SYNC();        HAL_DCACHE_DISABLE();    }    // Get base address and map addresses to virtual addresses    ROM = FLASH_P2V( CYGNUM_FLASH_BASE_MASK & (unsigned int)block );    block = FLASH_P2V(block);    // Clear any error conditions    ROM[0] = FLASH_Clear_Status;#ifdef CYGOPT_FLASH_IS_SYNCHRONOUS    // Clear lock bit    block[0] = FLASH_Clear_Locks;    block[0] = FLASH_Clear_Locks_Confirm;  // Confirmation    while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {        if (--timeout == 0) break;    }#else    // Get current block lock state.  This needs to access each block on    // the device so currently locked blocks can be re-locked.    bp = ROM;    for (i = 0;  i < blocks;  i++) {        bpv = FLASH_P2V( bp );        *bpv = FLASH_Read_Query;        if (bpv == block) {            is_locked[i] = 0;        } else {#if 8 == CYGNUM_FLASH_WIDTH            is_locked[i] = bpv[4] & FLASH_Lock_Bit;#else            is_locked[i] = bpv[2] & FLASH_Lock_Bit;# endif        }        bp += block_size / sizeof(*bp);    }    // Clears all lock bits    ROM[0] = FLASH_Clear_Locks;    ROM[0] = FLASH_Clear_Locks_Confirm;  // Confirmation    timeout = 5000000;    while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {        if (--timeout == 0) break;    }    // Restore the lock state    bp = ROM;    for (i = 0;  i < blocks;  i++) {        bpv = FLASH_P2V( bp );        if (is_locked[i]) {            *bpv = FLASH_Set_Lock;            *bpv = FLASH_Set_Lock_Confirm;  // Confirmation            timeout = 5000000;            while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {                if (--timeout == 0) break;            }        }        bp += block_size / sizeof(*bp);    }#endif  // CYGOPT_FLASH_IS_SYNCHRONOUS    // Restore ROM to "normal" mode    ROM[0] = FLASH_Reset;    if (cache_on) {        HAL_DCACHE_ENABLE();    }    return stat;}