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
16union 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 res1:31;
37		unsigned en:1;
38	} fam17h_bits;
39	unsigned long long val;
40};
41
42static 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 || family == 0x18)
49		t = pstate.fam17h_bits.did;
50	else
51		t = pstate.bits.did;
52
53	return t;
54}
55
56static 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 || family == 0x18) {
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 */
88int 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		if ((cpu_family == 0x17) && (!pstate.fam17h_bits.en))
123			continue;
124		else if (!pstate.bits.en)
125			continue;
126
127		pstates[i] = get_cof(cpu_family, pstate);
128	}
129	*no = i;
130	return 0;
131}
132
133int amd_pci_get_num_boost_states(int *active, int *states)
134{
135	struct pci_access *pci_acc;
136	struct pci_dev *device;
137	uint8_t val = 0;
138
139	*active = *states = 0;
140
141	device = pci_slot_func_init(&pci_acc, 0x18, 4);
142
143	if (device == NULL)
144		return -ENODEV;
145
146	val = pci_read_byte(device, 0x15c);
147	if (val & 3)
148		*active = 1;
149	else
150		*active = 0;
151	*states = (val >> 2) & 7;
152
153	pci_cleanup(pci_acc);
154	return 0;
155}
156#endif /* defined(__i386__) || defined(__x86_64__) */
157