1 /*
2 * QEMU model of the Xilinx eFuse core
3 *
4 * Copyright (c) 2015 Xilinx Inc.
5 *
6 * Written by Edgar E. Iglesias <edgari@xilinx.com>
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27 #ifndef XLNX_EFUSE_H
28 #define XLNX_EFUSE_H
29
30 #include "sysemu/block-backend.h"
31 #include "hw/qdev-core.h"
32
33 #define TYPE_XLNX_EFUSE "xlnx-efuse"
34 OBJECT_DECLARE_SIMPLE_TYPE(XlnxEFuse, XLNX_EFUSE);
35
36 struct XlnxEFuse {
37 DeviceState parent_obj;
38 BlockBackend *blk;
39 bool blk_ro;
40 uint32_t *fuse32;
41
42 DeviceState *dev;
43
44 bool init_tbits;
45
46 uint8_t efuse_nr;
47 uint32_t efuse_size;
48
49 uint32_t *ro_bits;
50 uint32_t ro_bits_cnt;
51 };
52
53 /**
54 * xlnx_efuse_calc_crc:
55 * @data: an array of 32-bit words for which the CRC should be computed
56 * @u32_cnt: the array size in number of 32-bit words
57 * @zpads: the number of 32-bit zeros prepended to @data before computation
58 *
59 * This function is used to compute the CRC for an array of 32-bit words,
60 * using a Xilinx-specific data padding.
61 *
62 * Returns: the computed 32-bit CRC
63 */
64 uint32_t xlnx_efuse_calc_crc(const uint32_t *data, unsigned u32_cnt,
65 unsigned zpads);
66
67 /**
68 * xlnx_efuse_get_bit:
69 * @s: the efuse object
70 * @bit: the efuse bit-address to read the data
71 *
72 * Returns: the bit, 0 or 1, at @bit of object @s
73 */
74 bool xlnx_efuse_get_bit(XlnxEFuse *s, unsigned int bit);
75
76 /**
77 * xlnx_efuse_set_bit:
78 * @s: the efuse object
79 * @bit: the efuse bit-address to be written a value of 1
80 *
81 * Returns: true on success, false on failure
82 */
83 bool xlnx_efuse_set_bit(XlnxEFuse *s, unsigned int bit);
84
85 /**
86 * xlnx_efuse_k256_check:
87 * @s: the efuse object
88 * @crc: the 32-bit CRC to be compared with
89 * @start: the efuse bit-address (which must be multiple of 32) of the
90 * start of a 256-bit array
91 *
92 * This function computes the CRC of a 256-bit array starting at @start
93 * then compares to the given @crc
94 *
95 * Returns: true of @crc == computed, false otherwise
96 */
97 bool xlnx_efuse_k256_check(XlnxEFuse *s, uint32_t crc, unsigned start);
98
99 /**
100 * xlnx_efuse_tbits_check:
101 * @s: the efuse object
102 *
103 * This function inspects a number of efuse bits at specific addresses
104 * to see if they match a validation pattern. Each pattern is a group
105 * of 4 bits, and there are 3 groups.
106 *
107 * Returns: a 3-bit mask, where a bit of '1' means the corresponding
108 * group has a valid pattern.
109 */
110 uint32_t xlnx_efuse_tbits_check(XlnxEFuse *s);
111
112 /**
113 * xlnx_efuse_get_row:
114 * @s: the efuse object
115 * @bit: the efuse bit address for which a 32-bit value is read
116 *
117 * Returns: the entire 32 bits of the efuse, starting at a bit
118 * address that is multiple of 32 and contains the bit at @bit
119 */
xlnx_efuse_get_row(XlnxEFuse * s,unsigned int bit)120 static inline uint32_t xlnx_efuse_get_row(XlnxEFuse *s, unsigned int bit)
121 {
122 if (!(s->fuse32)) {
123 return 0;
124 } else {
125 unsigned int row_idx = bit / 32;
126
127 assert(row_idx < (s->efuse_size * s->efuse_nr / 32));
128 return s->fuse32[row_idx];
129 }
130 }
131
132 #endif
133