1 //==========================================================================
3 // flash_unlock_block.c
7 //==========================================================================
8 //####ECOSGPLCOPYRIGHTBEGIN####
9 // -------------------------------------------
10 // This file is part of eCos, the Embedded Configurable Operating System.
11 // Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
13 // eCos is free software; you can redistribute it and/or modify it under
14 // the terms of the GNU General Public License as published by the Free
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18 // WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 // You should have received a copy of the GNU General Public License along
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24 // 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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27 // or inline functions from this file, or you compile this file and link it
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30 // License. However the source code for this file must still be made available
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37 // at http://sources.redhat.com/ecos/ecos-license/
38 // -------------------------------------------
39 //####ECOSGPLCOPYRIGHTEND####
40 //==========================================================================
41 //#####DESCRIPTIONBEGIN####
44 // Contributors: gthomas, msalter
49 //####DESCRIPTIONEND####
51 //==========================================================================
58 // The difficulty with this operation is that the hardware does not support
59 // unlocking single blocks. However, the logical layer would like this to
60 // be the case, so this routine emulates it. The hardware can clear all of
61 // the locks in the device at once. This routine will use that approach and
62 // then reset the regions which are known to be locked.
65 #define MAX_FLASH_BLOCKS 128
68 flash_unlock_block(volatile unsigned char *block, int block_size, int blocks)
69 __attribute__ ((section (".2ram.flash_unlock_block")));
71 flash_unlock_block(volatile unsigned char *block, int block_size, int blocks)
73 volatile unsigned short *ROM, *bp;
75 int timeout = 5000000;
76 unsigned short is_locked[MAX_FLASH_BLOCKS];
79 ROM = (unsigned short *) FLASH_P2V((unsigned long)block & 0xFF800000);
81 // Clear any error conditions
82 ROM[0] = FLASH_Clear_Status;
84 // Get current block lock state. This needs to access each block on
85 // the device so currently locked blocks can be re-locked.
86 bp = (unsigned short *)((unsigned long)block & 0xFF800000);
87 for (i = 0; i < blocks; i++) {
88 if (bp == (unsigned short *) block) {
91 *(volatile unsigned short *)FLASH_P2V(bp) = FLASH_Read_Query;
92 is_locked[i] = ((volatile unsigned short *)FLASH_P2V(bp))[2];
94 bp += block_size / sizeof(*bp);
97 // Clears all lock bits
98 FLASH_P2V(block)[0] = FLASH_Clear_Locks;
99 FLASH_P2V(block)[0] = FLASH_Clear_Locks_Confirm; // Confirmation
101 while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {
102 if (--timeout == 0) goto done;
105 // Restore the lock state
106 bp = (unsigned short *)((unsigned long)block & 0xFF800000);
107 for (i = 0; i < blocks; i++) {
109 *FLASH_P2V(bp) = FLASH_Set_Lock;
110 *FLASH_P2V(bp) = FLASH_Set_Lock_Confirm; // Confirmation
112 while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {
113 if (--timeout == 0) goto done;
116 bp += block_size / sizeof(*bp);
120 // Restore ROM to "normal" mode
121 ROM[0] = FLASH_Reset;