Tong Ho | 68fbcc3 | 2021-09-16 22:23:52 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Xilinx eFuse/bbram CRC calculator |
| 3 | * |
| 4 | * Copyright (c) 2021 Xilinx Inc. |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | */ |
| 24 | #include "qemu/osdep.h" |
| 25 | #include "hw/nvram/xlnx-efuse.h" |
| 26 | |
| 27 | static uint32_t xlnx_efuse_u37_crc(uint32_t prev_crc, uint32_t data, |
| 28 | uint32_t addr) |
| 29 | { |
| 30 | /* A table for 7-bit slicing */ |
| 31 | static const uint32_t crc_tab[128] = { |
| 32 | 0x00000000, 0xe13b70f7, 0xc79a971f, 0x26a1e7e8, |
| 33 | 0x8ad958cf, 0x6be22838, 0x4d43cfd0, 0xac78bf27, |
| 34 | 0x105ec76f, 0xf165b798, 0xd7c45070, 0x36ff2087, |
| 35 | 0x9a879fa0, 0x7bbcef57, 0x5d1d08bf, 0xbc267848, |
| 36 | 0x20bd8ede, 0xc186fe29, 0xe72719c1, 0x061c6936, |
| 37 | 0xaa64d611, 0x4b5fa6e6, 0x6dfe410e, 0x8cc531f9, |
| 38 | 0x30e349b1, 0xd1d83946, 0xf779deae, 0x1642ae59, |
| 39 | 0xba3a117e, 0x5b016189, 0x7da08661, 0x9c9bf696, |
| 40 | 0x417b1dbc, 0xa0406d4b, 0x86e18aa3, 0x67dafa54, |
| 41 | 0xcba24573, 0x2a993584, 0x0c38d26c, 0xed03a29b, |
| 42 | 0x5125dad3, 0xb01eaa24, 0x96bf4dcc, 0x77843d3b, |
| 43 | 0xdbfc821c, 0x3ac7f2eb, 0x1c661503, 0xfd5d65f4, |
| 44 | 0x61c69362, 0x80fde395, 0xa65c047d, 0x4767748a, |
| 45 | 0xeb1fcbad, 0x0a24bb5a, 0x2c855cb2, 0xcdbe2c45, |
| 46 | 0x7198540d, 0x90a324fa, 0xb602c312, 0x5739b3e5, |
| 47 | 0xfb410cc2, 0x1a7a7c35, 0x3cdb9bdd, 0xdde0eb2a, |
| 48 | 0x82f63b78, 0x63cd4b8f, 0x456cac67, 0xa457dc90, |
| 49 | 0x082f63b7, 0xe9141340, 0xcfb5f4a8, 0x2e8e845f, |
| 50 | 0x92a8fc17, 0x73938ce0, 0x55326b08, 0xb4091bff, |
| 51 | 0x1871a4d8, 0xf94ad42f, 0xdfeb33c7, 0x3ed04330, |
| 52 | 0xa24bb5a6, 0x4370c551, 0x65d122b9, 0x84ea524e, |
| 53 | 0x2892ed69, 0xc9a99d9e, 0xef087a76, 0x0e330a81, |
| 54 | 0xb21572c9, 0x532e023e, 0x758fe5d6, 0x94b49521, |
| 55 | 0x38cc2a06, 0xd9f75af1, 0xff56bd19, 0x1e6dcdee, |
| 56 | 0xc38d26c4, 0x22b65633, 0x0417b1db, 0xe52cc12c, |
| 57 | 0x49547e0b, 0xa86f0efc, 0x8ecee914, 0x6ff599e3, |
| 58 | 0xd3d3e1ab, 0x32e8915c, 0x144976b4, 0xf5720643, |
| 59 | 0x590ab964, 0xb831c993, 0x9e902e7b, 0x7fab5e8c, |
| 60 | 0xe330a81a, 0x020bd8ed, 0x24aa3f05, 0xc5914ff2, |
| 61 | 0x69e9f0d5, 0x88d28022, 0xae7367ca, 0x4f48173d, |
| 62 | 0xf36e6f75, 0x12551f82, 0x34f4f86a, 0xd5cf889d, |
| 63 | 0x79b737ba, 0x988c474d, 0xbe2da0a5, 0x5f16d052 |
| 64 | }; |
| 65 | |
| 66 | /* |
| 67 | * eFuse calculation is shown here: |
| 68 | * https://github.com/Xilinx/embeddedsw/blob/release-2019.2/lib/sw_services/xilskey/src/xilskey_utils.c#L1496 |
| 69 | * |
| 70 | * Each u32 word is appended a 5-bit value, for a total of 37 bits; see: |
| 71 | * https://github.com/Xilinx/embeddedsw/blob/release-2019.2/lib/sw_services/xilskey/src/xilskey_utils.c#L1356 |
| 72 | */ |
| 73 | uint32_t crc = prev_crc; |
| 74 | const unsigned rshf = 7; |
| 75 | const uint32_t im = (1 << rshf) - 1; |
| 76 | const uint32_t rm = (1 << (32 - rshf)) - 1; |
| 77 | const uint32_t i2 = (1 << 2) - 1; |
| 78 | const uint32_t r2 = (1 << 30) - 1; |
| 79 | |
| 80 | unsigned j; |
| 81 | uint32_t i, r; |
| 82 | uint64_t w; |
| 83 | |
| 84 | w = (uint64_t)(addr) << 32; |
| 85 | w |= data; |
| 86 | |
| 87 | /* Feed 35 bits, in 5 rounds, each a slice of 7 bits */ |
| 88 | for (j = 0; j < 5; j++) { |
| 89 | r = rm & (crc >> rshf); |
| 90 | i = im & (crc ^ w); |
| 91 | crc = crc_tab[i] ^ r; |
| 92 | |
| 93 | w >>= rshf; |
| 94 | } |
| 95 | |
| 96 | /* Feed the remaining 2 bits */ |
| 97 | r = r2 & (crc >> 2); |
| 98 | i = i2 & (crc ^ w); |
| 99 | crc = crc_tab[i << (rshf - 2)] ^ r; |
| 100 | |
| 101 | return crc; |
| 102 | } |
| 103 | |
| 104 | uint32_t xlnx_efuse_calc_crc(const uint32_t *data, unsigned u32_cnt, |
| 105 | unsigned zpads) |
| 106 | { |
| 107 | uint32_t crc = 0; |
| 108 | unsigned index; |
| 109 | |
| 110 | for (index = zpads; index; index--) { |
| 111 | crc = xlnx_efuse_u37_crc(crc, 0, (index + u32_cnt)); |
| 112 | } |
| 113 | |
| 114 | for (index = u32_cnt; index; index--) { |
| 115 | crc = xlnx_efuse_u37_crc(crc, data[index - 1], index); |
| 116 | } |
| 117 | |
| 118 | return crc; |
| 119 | } |