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
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19 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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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####
43 // Author(s): gthomas, hmt
44 // Contributors: gthomas
49 //####DESCRIPTIONEND####
51 //==========================================================================
57 // The difficulty with this operation is that the hardware does not support
58 // unlocking single blocks. However, the logical layer would like this to
59 // be the case, so this routine emulates it. The hardware can clear all of
60 // the locks in the device at once. This routine will use that approach and
61 // then reset the regions which are known to be locked.
64 #define FLASH_LOCK_MASK 0x1 // which bit of the read query has the lock bit
67 flash_unlock_block(volatile flash_t *block, int block_size, int blocks)
68 __attribute__ ((section (".2ram.flash_unlock_block")));
70 flash_unlock_block(volatile flash_t *block, int block_size, int blocks)
72 volatile flash_t *ROM;
74 int timeout = 5000000;
75 #ifndef CYGOPT_FLASH_IS_SYNCHRONOUS
77 volatile flash_t *bp, *bpv;
78 unsigned char is_locked[CYGNUM_DEVS_FLASH_STRATA_MAX_BLOCKS];
81 // Get base address and map addresses to virtual addresses
82 ROM = FLASH_P2V( CYGNUM_FLASH_BASE_MASK & (unsigned int)block );
83 block = FLASH_P2V(block);
85 // Clear any error conditions
86 ROM[0] = FLASH_Clear_Status;
88 #ifdef CYGOPT_FLASH_IS_SYNCHRONOUS
90 block[0] = FLASH_Clear_Locks;
91 block[0] = FLASH_Clear_Locks_Confirm; // Confirmation
92 while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {
93 if (--timeout == 0) break;
96 // Get current block lock state. This needs to access each block on
97 // the device so currently locked blocks can be re-locked.
99 for (i = 0; i < blocks; i++) {
100 bpv = FLASH_P2V( bp );
101 *bpv = FLASH_Read_Query;
105 #if 8 == CYGNUM_FLASH_WIDTH
106 is_locked[i] = bpv[4] & FLASH_LOCK_MASK;
108 is_locked[i] = bpv[2] & FLASH_LOCK_MASK;
111 bp += block_size / sizeof(*bp);
114 // Clears all lock bits
115 ROM[0] = FLASH_Clear_Locks;
116 ROM[0] = FLASH_Clear_Locks_Confirm; // Confirmation
118 while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {
119 if (--timeout == 0) break;
122 // Restore the lock state
124 for (i = 0; i < blocks; i++) {
125 bpv = FLASH_P2V( bp );
127 *bpv = FLASH_Set_Lock;
128 *bpv = FLASH_Set_Lock_Confirm; // Confirmation
130 while(((stat = ROM[0]) & FLASH_Status_Ready) != FLASH_Status_Ready) {
131 if (--timeout == 0) break;
134 bp += block_size / sizeof(*bp);
136 #endif // CYGOPT_FLASH_IS_SYNCHRONOUS
138 // Restore ROM to "normal" mode
139 ROM[0] = FLASH_Reset;