xref: /aosp_15_r20/external/coreboot/util/msrtool/freebsd.c (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #include <sys/types.h>
4 #include <sys/stat.h>
5 #include <fcntl.h>
6 #include <unistd.h>
7 #include <string.h>
8 #include <errno.h>
9 
10 #include "msrtool.h"
11 
12 static int msr_fd[MAX_CORES] = {-1, -1, -1, -1, -1, -1, -1, -1};
13 
freebsd_probe(const struct sysdef * system)14 int freebsd_probe(const struct sysdef *system)
15 {
16 #ifdef __FreeBSD__
17 	struct stat st;
18 
19 	return stat("/dev/cpuctl0", &st) == 0;
20 #else
21 	return 0;
22 #endif
23 }
24 
freebsd_open(uint8_t cpu,enum SysModes mode)25 int freebsd_open(uint8_t cpu, enum SysModes mode)
26 {
27 #ifdef __FreeBSD__
28 	int flags;
29 	char devname[32];
30 
31 	if (cpu >= MAX_CORES)
32 		return 0;
33 
34 	if (SYS_RDWR == mode)
35 		flags = O_RDWR;
36 	else if (SYS_WRONLY == mode)
37 		flags = O_WRONLY;
38 	else
39 		flags = O_RDONLY;
40 
41 	snprintf(devname, sizeof(devname), "/dev/cpuctl%u", cpu);
42 	msr_fd[cpu] = open(devname, flags);
43 	if (msr_fd[cpu] < 0) {
44 		perror(devname);
45 		return 0;
46 	}
47 	return 1;
48 #else
49 	return 0;
50 #endif
51 }
52 
freebsd_close(uint8_t cpu)53 int freebsd_close(uint8_t cpu)
54 {
55 	if (cpu >= MAX_CORES)
56 		return 0;
57 
58 	if (msr_fd[cpu] != -1)
59 		close(msr_fd[cpu]);
60 	msr_fd[cpu] = -1;
61 	return 1;
62 }
63 
freebsd_rdmsr(uint8_t cpu,uint32_t addr,struct msr * val)64 int freebsd_rdmsr(uint8_t cpu, uint32_t addr, struct msr *val)
65 {
66 #ifdef __FreeBSD__
67 	cpuctl_msr_args_t args;
68 
69 	if (cpu >= MAX_CORES)
70 		return 0;
71 
72 	if (msr_fd[cpu] < 0)
73 		return 0;
74 
75 	args.msr = addr;
76 	if (ioctl(msr_fd[cpu], CPUCTL_RDMSR, &args) < 0) {
77 		perror("ioctl(CPUCTL_RDMSR)");
78 		return 0;
79 	}
80 
81 	val->hi = args.data >> 32;
82 	val->lo = args.data & 0xffffffff;
83 	return 1;
84 #else
85 	return 0;
86 #endif
87 }
88