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| 1 | 3e3d5815 | balrog | /*
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| 2 | 3e3d5815 | balrog | * Calculate Error-correcting Codes. Used by NAND Flash controllers
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| 3 | 3e3d5815 | balrog | * (not by NAND chips).
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| 4 | 3e3d5815 | balrog | *
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| 5 | 3e3d5815 | balrog | * Copyright (c) 2006 Openedhand Ltd.
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| 6 | 3e3d5815 | balrog | * Written by Andrzej Zaborowski <balrog@zabor.org>
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| 7 | 3e3d5815 | balrog | *
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| 8 | 3e3d5815 | balrog | * This code is licensed under the GNU GPL v2.
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| 9 | 3e3d5815 | balrog | */
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| 10 | 3e3d5815 | balrog | |
| 11 | 9ff6755b | balrog | #include "vl.h" |
| 12 | 3e3d5815 | balrog | |
| 13 | 3e3d5815 | balrog | /*
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| 14 | 3e3d5815 | balrog | * Pre-calculated 256-way 1 byte column parity. Table borrowed from Linux.
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| 15 | 3e3d5815 | balrog | */
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| 16 | 3e3d5815 | balrog | static const uint8_t nand_ecc_precalc_table[] = { |
| 17 | 3e3d5815 | balrog | 0x00, 0x55, 0x56, 0x03, 0x59, 0x0c, 0x0f, 0x5a, |
| 18 | 3e3d5815 | balrog | 0x5a, 0x0f, 0x0c, 0x59, 0x03, 0x56, 0x55, 0x00, |
| 19 | 3e3d5815 | balrog | 0x65, 0x30, 0x33, 0x66, 0x3c, 0x69, 0x6a, 0x3f, |
| 20 | 3e3d5815 | balrog | 0x3f, 0x6a, 0x69, 0x3c, 0x66, 0x33, 0x30, 0x65, |
| 21 | 3e3d5815 | balrog | 0x66, 0x33, 0x30, 0x65, 0x3f, 0x6a, 0x69, 0x3c, |
| 22 | 3e3d5815 | balrog | 0x3c, 0x69, 0x6a, 0x3f, 0x65, 0x30, 0x33, 0x66, |
| 23 | 3e3d5815 | balrog | 0x03, 0x56, 0x55, 0x00, 0x5a, 0x0f, 0x0c, 0x59, |
| 24 | 3e3d5815 | balrog | 0x59, 0x0c, 0x0f, 0x5a, 0x00, 0x55, 0x56, 0x03, |
| 25 | 3e3d5815 | balrog | 0x69, 0x3c, 0x3f, 0x6a, 0x30, 0x65, 0x66, 0x33, |
| 26 | 3e3d5815 | balrog | 0x33, 0x66, 0x65, 0x30, 0x6a, 0x3f, 0x3c, 0x69, |
| 27 | 3e3d5815 | balrog | 0x0c, 0x59, 0x5a, 0x0f, 0x55, 0x00, 0x03, 0x56, |
| 28 | 3e3d5815 | balrog | 0x56, 0x03, 0x00, 0x55, 0x0f, 0x5a, 0x59, 0x0c, |
| 29 | 3e3d5815 | balrog | 0x0f, 0x5a, 0x59, 0x0c, 0x56, 0x03, 0x00, 0x55, |
| 30 | 3e3d5815 | balrog | 0x55, 0x00, 0x03, 0x56, 0x0c, 0x59, 0x5a, 0x0f, |
| 31 | 3e3d5815 | balrog | 0x6a, 0x3f, 0x3c, 0x69, 0x33, 0x66, 0x65, 0x30, |
| 32 | 3e3d5815 | balrog | 0x30, 0x65, 0x66, 0x33, 0x69, 0x3c, 0x3f, 0x6a, |
| 33 | 3e3d5815 | balrog | 0x6a, 0x3f, 0x3c, 0x69, 0x33, 0x66, 0x65, 0x30, |
| 34 | 3e3d5815 | balrog | 0x30, 0x65, 0x66, 0x33, 0x69, 0x3c, 0x3f, 0x6a, |
| 35 | 3e3d5815 | balrog | 0x0f, 0x5a, 0x59, 0x0c, 0x56, 0x03, 0x00, 0x55, |
| 36 | 3e3d5815 | balrog | 0x55, 0x00, 0x03, 0x56, 0x0c, 0x59, 0x5a, 0x0f, |
| 37 | 3e3d5815 | balrog | 0x0c, 0x59, 0x5a, 0x0f, 0x55, 0x00, 0x03, 0x56, |
| 38 | 3e3d5815 | balrog | 0x56, 0x03, 0x00, 0x55, 0x0f, 0x5a, 0x59, 0x0c, |
| 39 | 3e3d5815 | balrog | 0x69, 0x3c, 0x3f, 0x6a, 0x30, 0x65, 0x66, 0x33, |
| 40 | 3e3d5815 | balrog | 0x33, 0x66, 0x65, 0x30, 0x6a, 0x3f, 0x3c, 0x69, |
| 41 | 3e3d5815 | balrog | 0x03, 0x56, 0x55, 0x00, 0x5a, 0x0f, 0x0c, 0x59, |
| 42 | 3e3d5815 | balrog | 0x59, 0x0c, 0x0f, 0x5a, 0x00, 0x55, 0x56, 0x03, |
| 43 | 3e3d5815 | balrog | 0x66, 0x33, 0x30, 0x65, 0x3f, 0x6a, 0x69, 0x3c, |
| 44 | 3e3d5815 | balrog | 0x3c, 0x69, 0x6a, 0x3f, 0x65, 0x30, 0x33, 0x66, |
| 45 | 3e3d5815 | balrog | 0x65, 0x30, 0x33, 0x66, 0x3c, 0x69, 0x6a, 0x3f, |
| 46 | 3e3d5815 | balrog | 0x3f, 0x6a, 0x69, 0x3c, 0x66, 0x33, 0x30, 0x65, |
| 47 | 3e3d5815 | balrog | 0x00, 0x55, 0x56, 0x03, 0x59, 0x0c, 0x0f, 0x5a, |
| 48 | 3e3d5815 | balrog | 0x5a, 0x0f, 0x0c, 0x59, 0x03, 0x56, 0x55, 0x00, |
| 49 | 3e3d5815 | balrog | }; |
| 50 | 3e3d5815 | balrog | |
| 51 | 3e3d5815 | balrog | /* Update ECC parity count. */
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| 52 | 9ff6755b | balrog | uint8_t ecc_digest(struct ecc_state_s *s, uint8_t sample)
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| 53 | 3e3d5815 | balrog | {
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| 54 | 3e3d5815 | balrog | uint8_t idx = nand_ecc_precalc_table[sample]; |
| 55 | 3e3d5815 | balrog | |
| 56 | 3e3d5815 | balrog | s->cp ^= idx & 0x3f;
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| 57 | 3e3d5815 | balrog | if (idx & 0x40) { |
| 58 | 3e3d5815 | balrog | s->lp[0] ^= ~s->count;
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| 59 | 3e3d5815 | balrog | s->lp[1] ^= s->count;
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| 60 | 3e3d5815 | balrog | } |
| 61 | 3e3d5815 | balrog | s->count ++; |
| 62 | 3e3d5815 | balrog | |
| 63 | 3e3d5815 | balrog | return sample;
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| 64 | 3e3d5815 | balrog | } |
| 65 | 3e3d5815 | balrog | |
| 66 | 3e3d5815 | balrog | /* Reinitialise the counters. */
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| 67 | 9ff6755b | balrog | void ecc_reset(struct ecc_state_s *s) |
| 68 | 3e3d5815 | balrog | {
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| 69 | 3e3d5815 | balrog | s->lp[0] = 0x0000; |
| 70 | 3e3d5815 | balrog | s->lp[1] = 0x0000; |
| 71 | 3e3d5815 | balrog | s->cp = 0x00;
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| 72 | 3e3d5815 | balrog | s->count = 0;
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| 73 | 3e3d5815 | balrog | } |
| 74 | aa941b94 | balrog | |
| 75 | aa941b94 | balrog | /* Save/restore */
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| 76 | 9ff6755b | balrog | void ecc_put(QEMUFile *f, struct ecc_state_s *s) |
| 77 | aa941b94 | balrog | {
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| 78 | aa941b94 | balrog | qemu_put_8s(f, &s->cp); |
| 79 | aa941b94 | balrog | qemu_put_be16s(f, &s->lp[0]);
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| 80 | aa941b94 | balrog | qemu_put_be16s(f, &s->lp[1]);
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| 81 | aa941b94 | balrog | qemu_put_be16s(f, &s->count); |
| 82 | aa941b94 | balrog | } |
| 83 | aa941b94 | balrog | |
| 84 | 9ff6755b | balrog | void ecc_get(QEMUFile *f, struct ecc_state_s *s) |
| 85 | aa941b94 | balrog | {
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| 86 | aa941b94 | balrog | qemu_get_8s(f, &s->cp); |
| 87 | aa941b94 | balrog | qemu_get_be16s(f, &s->lp[0]);
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| 88 | aa941b94 | balrog | qemu_get_be16s(f, &s->lp[1]);
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| 89 | aa941b94 | balrog | qemu_get_be16s(f, &s->count); |
| 90 | aa941b94 | balrog | } |