PPC: e500: msync is 440 only, e500 has real sync
[qemu.git] / hw / ecc.c
1 /*
2 * Calculate Error-correcting Codes. Used by NAND Flash controllers
3 * (not by NAND chips).
4 *
5 * Copyright (c) 2006 Openedhand Ltd.
6 * Written by Andrzej Zaborowski <balrog@zabor.org>
7 *
8 * This code is licensed under the GNU GPL v2.
9 *
10 * Contributions after 2012-01-13 are licensed under the terms of the
11 * GNU GPL, version 2 or (at your option) any later version.
12 */
13
14 #include "hw.h"
15 #include "flash.h"
16
17 /*
18 * Pre-calculated 256-way 1 byte column parity. Table borrowed from Linux.
19 */
20 static const uint8_t nand_ecc_precalc_table[] = {
21 0x00, 0x55, 0x56, 0x03, 0x59, 0x0c, 0x0f, 0x5a,
22 0x5a, 0x0f, 0x0c, 0x59, 0x03, 0x56, 0x55, 0x00,
23 0x65, 0x30, 0x33, 0x66, 0x3c, 0x69, 0x6a, 0x3f,
24 0x3f, 0x6a, 0x69, 0x3c, 0x66, 0x33, 0x30, 0x65,
25 0x66, 0x33, 0x30, 0x65, 0x3f, 0x6a, 0x69, 0x3c,
26 0x3c, 0x69, 0x6a, 0x3f, 0x65, 0x30, 0x33, 0x66,
27 0x03, 0x56, 0x55, 0x00, 0x5a, 0x0f, 0x0c, 0x59,
28 0x59, 0x0c, 0x0f, 0x5a, 0x00, 0x55, 0x56, 0x03,
29 0x69, 0x3c, 0x3f, 0x6a, 0x30, 0x65, 0x66, 0x33,
30 0x33, 0x66, 0x65, 0x30, 0x6a, 0x3f, 0x3c, 0x69,
31 0x0c, 0x59, 0x5a, 0x0f, 0x55, 0x00, 0x03, 0x56,
32 0x56, 0x03, 0x00, 0x55, 0x0f, 0x5a, 0x59, 0x0c,
33 0x0f, 0x5a, 0x59, 0x0c, 0x56, 0x03, 0x00, 0x55,
34 0x55, 0x00, 0x03, 0x56, 0x0c, 0x59, 0x5a, 0x0f,
35 0x6a, 0x3f, 0x3c, 0x69, 0x33, 0x66, 0x65, 0x30,
36 0x30, 0x65, 0x66, 0x33, 0x69, 0x3c, 0x3f, 0x6a,
37 0x6a, 0x3f, 0x3c, 0x69, 0x33, 0x66, 0x65, 0x30,
38 0x30, 0x65, 0x66, 0x33, 0x69, 0x3c, 0x3f, 0x6a,
39 0x0f, 0x5a, 0x59, 0x0c, 0x56, 0x03, 0x00, 0x55,
40 0x55, 0x00, 0x03, 0x56, 0x0c, 0x59, 0x5a, 0x0f,
41 0x0c, 0x59, 0x5a, 0x0f, 0x55, 0x00, 0x03, 0x56,
42 0x56, 0x03, 0x00, 0x55, 0x0f, 0x5a, 0x59, 0x0c,
43 0x69, 0x3c, 0x3f, 0x6a, 0x30, 0x65, 0x66, 0x33,
44 0x33, 0x66, 0x65, 0x30, 0x6a, 0x3f, 0x3c, 0x69,
45 0x03, 0x56, 0x55, 0x00, 0x5a, 0x0f, 0x0c, 0x59,
46 0x59, 0x0c, 0x0f, 0x5a, 0x00, 0x55, 0x56, 0x03,
47 0x66, 0x33, 0x30, 0x65, 0x3f, 0x6a, 0x69, 0x3c,
48 0x3c, 0x69, 0x6a, 0x3f, 0x65, 0x30, 0x33, 0x66,
49 0x65, 0x30, 0x33, 0x66, 0x3c, 0x69, 0x6a, 0x3f,
50 0x3f, 0x6a, 0x69, 0x3c, 0x66, 0x33, 0x30, 0x65,
51 0x00, 0x55, 0x56, 0x03, 0x59, 0x0c, 0x0f, 0x5a,
52 0x5a, 0x0f, 0x0c, 0x59, 0x03, 0x56, 0x55, 0x00,
53 };
54
55 /* Update ECC parity count. */
56 uint8_t ecc_digest(ECCState *s, uint8_t sample)
57 {
58 uint8_t idx = nand_ecc_precalc_table[sample];
59
60 s->cp ^= idx & 0x3f;
61 if (idx & 0x40) {
62 s->lp[0] ^= ~s->count;
63 s->lp[1] ^= s->count;
64 }
65 s->count ++;
66
67 return sample;
68 }
69
70 /* Reinitialise the counters. */
71 void ecc_reset(ECCState *s)
72 {
73 s->lp[0] = 0x0000;
74 s->lp[1] = 0x0000;
75 s->cp = 0x00;
76 s->count = 0;
77 }
78
79 /* Save/restore */
80 VMStateDescription vmstate_ecc_state = {
81 .name = "ecc-state",
82 .version_id = 0,
83 .minimum_version_id = 0,
84 .minimum_version_id_old = 0,
85 .fields = (VMStateField []) {
86 VMSTATE_UINT8(cp, ECCState),
87 VMSTATE_UINT16_ARRAY(lp, ECCState, 2),
88 VMSTATE_UINT16(count, ECCState),
89 VMSTATE_END_OF_LIST(),
90 },
91 };