1 // SPDX-License-Identifier: GPL-2.0
2 #if defined(__i386__) || defined(__x86_64__)
3 #include <unistd.h>
4 #include <errno.h>
5 #include <stdio.h>
6 #include <stdint.h>
7
8 #include <pci/pci.h>
9
10 #include "helpers/helpers.h"
11
12 #define MSR_AMD_PSTATE_STATUS 0xc0010063
13 #define MSR_AMD_PSTATE 0xc0010064
14 #define MSR_AMD_PSTATE_LIMIT 0xc0010061
15
16 union msr_pstate {
17 struct {
18 unsigned fid:6;
19 unsigned did:3;
20 unsigned vid:7;
21 unsigned res1:6;
22 unsigned nbdid:1;
23 unsigned res2:2;
24 unsigned nbvid:7;
25 unsigned iddval:8;
26 unsigned idddiv:2;
27 unsigned res3:21;
28 unsigned en:1;
29 } bits;
30 struct {
31 unsigned fid:8;
32 unsigned did:6;
33 unsigned vid:8;
34 unsigned iddval:8;
35 unsigned idddiv:2;
36 unsigned res1:30;
37 unsigned en:1;
38 } fam17h_bits;
39 unsigned long long val;
40 };
41
get_did(int family,union msr_pstate pstate)42 static int get_did(int family, union msr_pstate pstate)
43 {
44 int t;
45
46 if (family == 0x12)
47 t = pstate.val & 0xf;
48 else if (family == 0x17)
49 t = pstate.fam17h_bits.did;
50 else
51 t = pstate.bits.did;
52
53 return t;
54 }
55
get_cof(int family,union msr_pstate pstate)56 static int get_cof(int family, union msr_pstate pstate)
57 {
58 int t;
59 int fid, did, cof;
60
61 did = get_did(family, pstate);
62 if (family == 0x17) {
63 fid = pstate.fam17h_bits.fid;
64 cof = 200 * fid / did;
65 } else {
66 t = 0x10;
67 fid = pstate.bits.fid;
68 if (family == 0x11)
69 t = 0x8;
70 cof = (100 * (fid + t)) >> did;
71 }
72 return cof;
73 }
74
75 /* Needs:
76 * cpu -> the cpu that gets evaluated
77 * cpu_family -> The cpu's family (0x10, 0x12,...)
78 * boots_states -> how much boost states the machines support
79 *
80 * Fills up:
81 * pstates -> a pointer to an array of size MAX_HW_PSTATES
82 * must be initialized with zeros.
83 * All available HW pstates (including boost states)
84 * no -> amount of pstates above array got filled up with
85 *
86 * returns zero on success, -1 on failure
87 */
decode_pstates(unsigned int cpu,unsigned int cpu_family,int boost_states,unsigned long * pstates,int * no)88 int decode_pstates(unsigned int cpu, unsigned int cpu_family,
89 int boost_states, unsigned long *pstates, int *no)
90 {
91 int i, psmax, pscur;
92 union msr_pstate pstate;
93 unsigned long long val;
94
95 /* Only read out frequencies from HW when CPU might be boostable
96 to keep the code as short and clean as possible.
97 Otherwise frequencies are exported via ACPI tables.
98 */
99 if (cpu_family < 0x10 || cpu_family == 0x14)
100 return -1;
101
102 if (read_msr(cpu, MSR_AMD_PSTATE_LIMIT, &val))
103 return -1;
104
105 psmax = (val >> 4) & 0x7;
106
107 if (read_msr(cpu, MSR_AMD_PSTATE_STATUS, &val))
108 return -1;
109
110 pscur = val & 0x7;
111
112 pscur += boost_states;
113 psmax += boost_states;
114 for (i = 0; i <= psmax; i++) {
115 if (i >= MAX_HW_PSTATES) {
116 fprintf(stderr, "HW pstates [%d] exceeding max [%d]\n",
117 psmax, MAX_HW_PSTATES);
118 return -1;
119 }
120 if (read_msr(cpu, MSR_AMD_PSTATE + i, &pstate.val))
121 return -1;
122 pstates[i] = get_cof(cpu_family, pstate);
123 }
124 *no = i;
125 return 0;
126 }
127
amd_pci_get_num_boost_states(int * active,int * states)128 int amd_pci_get_num_boost_states(int *active, int *states)
129 {
130 struct pci_access *pci_acc;
131 struct pci_dev *device;
132 uint8_t val = 0;
133
134 *active = *states = 0;
135
136 device = pci_slot_func_init(&pci_acc, 0x18, 4);
137
138 if (device == NULL)
139 return -ENODEV;
140
141 val = pci_read_byte(device, 0x15c);
142 if (val & 3)
143 *active = 1;
144 else
145 *active = 0;
146 *states = (val >> 2) & 7;
147
148 pci_cleanup(pci_acc);
149 return 0;
150 }
151 #endif /* defined(__i386__) || defined(__x86_64__) */
152
