| 1 | /* |
| 2 | * ========== Copyright Header Begin ========================================== |
| 3 | * |
| 4 | * OpenSPARC T2 Processor File: BL_Hsiao_256_10_Synd.h |
| 5 | * Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. |
| 6 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES. |
| 7 | * |
| 8 | * The above named program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public |
| 10 | * License version 2 as published by the Free Software Foundation. |
| 11 | * |
| 12 | * The above named program is distributed in the hope that it will be |
| 13 | * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public |
| 18 | * License along with this work; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. |
| 20 | * |
| 21 | * ========== Copyright Header End ============================================ |
| 22 | */ |
| 23 | /************************************************************************ |
| 24 | ** |
| 25 | ** Copyright (C) 2006, Sun Microsystems, Inc. |
| 26 | ** |
| 27 | ** Sun considers its source code as an unpublished, proprietary |
| 28 | ** trade secret and it is available only under strict license provisions. |
| 29 | ** This copyright notice is placed here only to protect Sun in the event |
| 30 | ** the source is deemed a published work. Disassembly, decompilation, |
| 31 | ** or other means of reducing the object code to human readable form |
| 32 | ** is prohibited by the license agreement under which this code is |
| 33 | ** provided to the user or company in possession of this copy. |
| 34 | ** |
| 35 | *************************************************************************/ |
| 36 | #ifndef __BL_Hsiao_256_10_Synd_h__ |
| 37 | #define __BL_Hsiao_256_10_Synd_h__ |
| 38 | #include "BL_Utils.h" |
| 39 | #include "BL_BaseSynd.h" |
| 40 | #include "BL_HsiaoEcc.h" |
| 41 | |
| 42 | class BL_Hsiao_256_10_Synd : public BL_BaseSynd |
| 43 | { |
| 44 | public: |
| 45 | |
| 46 | BL_Hsiao_256_10_Synd(uint32_t syndrome) : BL_BaseSynd(syndrome) |
| 47 | { |
| 48 | if (syndrome > 0x3ff) |
| 49 | { |
| 50 | fprintf(stderr,"ERROR: Bad Syndrome: 0x%x", syndrome); |
| 51 | exit(-1); |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | BL_Hsiao_256_10_Synd(BL_Uint256 data, BL_EccBits ecc) : |
| 56 | BL_BaseSynd(BL_Hsiao_256_10_Synd::calc_check_bits(data).get() ^ ecc.get()) |
| 57 | {} |
| 58 | |
| 59 | |
| 60 | ~BL_Hsiao_256_10_Synd() {} |
| 61 | |
| 62 | bool isDoubleBitError() const |
| 63 | { |
| 64 | return (syndrome_ != 0) && !isSingleBitError(); |
| 65 | } |
| 66 | |
| 67 | bool isSingleBitError() const |
| 68 | { |
| 69 | if (syndrome_ == 0) |
| 70 | return false; |
| 71 | switch (nr_bits_set()) |
| 72 | { |
| 73 | case 1: |
| 74 | case 3: |
| 75 | return true; |
| 76 | case 5: |
| 77 | return find_syndrome_ndx() != -1; |
| 78 | default: |
| 79 | return false; |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | bool isDataBitError() const |
| 84 | { |
| 85 | return (isSingleBitError() && nr_bits_set() > 1); |
| 86 | } |
| 87 | |
| 88 | // This method works because the check bits are at powers of 2 |
| 89 | // (after substracting 0x80) so the data bits break up into |
| 90 | // large ranges. |
| 91 | uint32_t getDataBit() const |
| 92 | { |
| 93 | if (!isDataBitError()) |
| 94 | { |
| 95 | fprintf(stderr,"ERROR: Not data bit error!"); |
| 96 | exit(-1); |
| 97 | } |
| 98 | |
| 99 | return find_syndrome_ndx(); |
| 100 | } |
| 101 | |
| 102 | bool isCheckBitError() const |
| 103 | { |
| 104 | return (isSingleBitError() && is_power_of_two(syndrome_)); |
| 105 | } |
| 106 | |
| 107 | uint32_t getCheckBit() const |
| 108 | { |
| 109 | if (!isCheckBitError()) |
| 110 | { |
| 111 | fprintf(stderr,"ERROR: Not check bit error!"); |
| 112 | exit(-1); |
| 113 | } |
| 114 | return bit2idx(syndrome_); |
| 115 | } |
| 116 | |
| 117 | bool isMultipleBitError() const { return false; } |
| 118 | |
| 119 | static BL_EccBits calc_check_bits(BL_Uint256 data) |
| 120 | { |
| 121 | BL_Uint256 *patterns = |
| 122 | BL_Hsiao_256_10_Synd::hsiao_256_10_patterns.patterns; |
| 123 | return calc_checks(10, patterns, data); |
| 124 | |
| 125 | } |
| 126 | |
| 127 | private: |
| 128 | |
| 129 | BL_Hsiao_256_10_Synd(); |
| 130 | |
| 131 | // Number of bits set in syndrome |
| 132 | // This trick works up to 12 bits |
| 133 | uint_t nr_bits_set() const |
| 134 | { |
| 135 | return (syndrome_ * 0x1001001001001ULL & 0x84210842108421ULL) % 0x1f; |
| 136 | } |
| 137 | |
| 138 | int find_syndrome_ndx() const |
| 139 | { |
| 140 | switch (nr_bits_set()) |
| 141 | { |
| 142 | case 3: |
| 143 | for (uint_t ndx = 0; ndx < 120; ++ndx) |
| 144 | if (syndrome_ == hsiao_256_10_patterns.get(ndx).get()) |
| 145 | return ndx; |
| 146 | assert(0); |
| 147 | break; |
| 148 | case 5: |
| 149 | for (uint_t ndx = 120; ndx < 256; ++ndx) |
| 150 | if (syndrome_ == hsiao_256_10_patterns.get(ndx).get()) |
| 151 | return ndx; |
| 152 | default: |
| 153 | break; |
| 154 | } |
| 155 | return -1; // -1 is didn't find it |
| 156 | } |
| 157 | |
| 158 | class Patterns |
| 159 | { |
| 160 | public: |
| 161 | BL_Uint256 patterns[10]; |
| 162 | |
| 163 | Patterns(); |
| 164 | |
| 165 | ~Patterns() {} |
| 166 | |
| 167 | BL_EccBits get(uint_t ndx) const { return syndromes[ndx]; } |
| 168 | |
| 169 | private: |
| 170 | |
| 171 | static uint64_t calc_pattern(uint_t syndrome_ndx, uint_t pattern_ndx); |
| 172 | |
| 173 | static BL_EccBits syndromes[256]; |
| 174 | }; |
| 175 | |
| 176 | static Patterns hsiao_256_10_patterns; |
| 177 | |
| 178 | }; |
| 179 | |
| 180 | #endif |