pyrox.dev
1/*
2 * Convert Intel microcode.dat into a single binary microcode.bin file
3 *
4 * Based on code by Kay Sievers <kay.sievers@vrfy.org>
5 * Changed to create a single file by Thomas Bächler <thomas@archlinux.org>
6 */
7
8
9#ifndef _GNU_SOURCE
10# define _GNU_SOURCE 1
11#endif
12
13#include <stdio.h>
14#include <unistd.h>
15#include <stdlib.h>
16#include <string.h>
17#include <time.h>
18#include <limits.h>
19#include <stdbool.h>
20#include <inttypes.h>
21#include <fcntl.h>
22#include <errno.h>
23#include <sys/stat.h>
24
25struct microcode_header_intel {
26 unsigned int hdrver;
27 unsigned int rev;
28 unsigned int date;
29 unsigned int sig;
30 unsigned int cksum;
31 unsigned int ldrver;
32 unsigned int pf;
33 unsigned int datasize;
34 unsigned int totalsize;
35 unsigned int reserved[3];
36};
37
38union mcbuf {
39 struct microcode_header_intel hdr;
40 unsigned int i[0];
41 char c[0];
42};
43
44int main(int argc, char *argv[])
45{
46 const char *filename = "/lib/firmware/microcode.dat";
47 FILE *f;
48 char line[LINE_MAX];
49 char buf[4000000];
50 union mcbuf *mc;
51 size_t bufsize, count, start;
52 int rc = EXIT_SUCCESS;
53
54 if (argv[1] != NULL)
55 filename = argv[1];
56
57 count = 0;
58 mc = (union mcbuf *) buf;
59 f = fopen(filename, "re");
60 if (f == NULL) {
61 printf("open %s: %m\n", filename);
62 rc = EXIT_FAILURE;
63 goto out;
64 }
65
66 while (fgets(line, sizeof(line), f) != NULL) {
67 if (sscanf(line, "%x, %x, %x, %x",
68 &mc->i[count],
69 &mc->i[count + 1],
70 &mc->i[count + 2],
71 &mc->i[count + 3]) != 4)
72 continue;
73 count += 4;
74 }
75 fclose(f);
76
77 bufsize = count * sizeof(int);
78 printf("%s: %lu(%luk) bytes, %zu integers\n",
79 filename,
80 bufsize,
81 bufsize / 1024,
82 count);
83
84 if (bufsize < sizeof(struct microcode_header_intel))
85 goto out;
86
87 f = fopen("microcode.bin", "we");
88 if (f == NULL) {
89 printf("open microcode.bin: %m\n");
90 rc = EXIT_FAILURE;
91 goto out;
92 }
93
94 start = 0;
95 for (;;) {
96 size_t size;
97 unsigned int family, model, stepping;
98 unsigned int year, month, day;
99
100 mc = (union mcbuf *) &buf[start];
101
102 if (mc->hdr.totalsize)
103 size = mc->hdr.totalsize;
104 else
105 size = 2000 + sizeof(struct microcode_header_intel);
106
107 if (mc->hdr.ldrver != 1 || mc->hdr.hdrver != 1) {
108 printf("unknown version/format:\n");
109 rc = EXIT_FAILURE;
110 break;
111 }
112
113 /*
114 * 0- 3 stepping
115 * 4- 7 model
116 * 8-11 family
117 * 12-13 type
118 * 16-19 extended model
119 * 20-27 extended family
120 */
121 family = (mc->hdr.sig >> 8) & 0xf;
122 if (family == 0xf)
123 family += (mc->hdr.sig >> 20) & 0xff;
124 model = (mc->hdr.sig >> 4) & 0x0f;
125 if (family == 0x06)
126 model += ((mc->hdr.sig >> 16) & 0x0f) << 4;
127 stepping = mc->hdr.sig & 0x0f;
128
129 year = mc->hdr.date & 0xffff;
130 month = mc->hdr.date >> 24;
131 day = (mc->hdr.date >> 16) & 0xff;
132
133 printf("\n");
134 printf("signature: 0x%02x\n", mc->hdr.sig);
135 printf("flags: 0x%02x\n", mc->hdr.pf);
136 printf("revision: 0x%02x\n", mc->hdr.rev);
137 printf("date: %04x-%02x-%02x\n", year, month, day);
138 printf("size: %zu\n", size);
139
140 if (fwrite(mc, size, 1, f) != 1) {
141 printf("write microcode.bin: %m\n");
142 rc = EXIT_FAILURE;
143 goto out;
144 }
145
146 start += size;
147 if (start >= bufsize)
148 break;
149 }
150 fclose(f);
151 printf("\n");
152out:
153 return rc;
154}