xref: /linux/drivers/cpufreq/amd-pstate.h (revision c89756bcf406af313d191cfe3709e7c175c5b0cd)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2022 Advanced Micro Devices, Inc.
4  *
5  * Author: Meng Li <li.meng@amd.com>
6  */
7 
8 #ifndef _LINUX_AMD_PSTATE_H
9 #define _LINUX_AMD_PSTATE_H
10 
11 #include <linux/pm_qos.h>
12 
13 /*********************************************************************
14  *                        AMD P-state INTERFACE                       *
15  *********************************************************************/
16 
17 /**
18  * union perf_cached - A union to cache performance-related data.
19  * @highest_perf: the maximum performance an individual processor may reach,
20  *		  assuming ideal conditions
21  *		  For platforms that support the preferred core feature, the highest_perf value maybe
22  * 		  configured to any value in the range 166-255 by the firmware (because the preferred
23  * 		  core ranking is encoded in the highest_perf value). To maintain consistency across
24  * 		  all platforms, we split the highest_perf and preferred core ranking values into
25  * 		  cpudata->perf.highest_perf and cpudata->prefcore_ranking.
26  * @nominal_perf: the maximum sustained performance level of the processor,
27  *		  assuming ideal operating conditions
28  * @lowest_nonlinear_perf: the lowest performance level at which nonlinear power
29  *			   savings are achieved
30  * @lowest_perf: the absolute lowest performance level of the processor
31  * @min_limit_perf: Cached value of the performance corresponding to policy->min
32  * @max_limit_perf: Cached value of the performance corresponding to policy->max
33  * @bios_min_perf: Cached perf value corresponding to the "Requested CPU Min Frequency" BIOS option
34  */
35 union perf_cached {
36 	struct {
37 		u8	highest_perf;
38 		u8	nominal_perf;
39 		u8	lowest_nonlinear_perf;
40 		u8	lowest_perf;
41 		u8	min_limit_perf;
42 		u8	max_limit_perf;
43 		u8	bios_min_perf;
44 	};
45 	u64	val;
46 };
47 
48 /**
49  * struct  amd_aperf_mperf
50  * @aperf: actual performance frequency clock count
51  * @mperf: maximum performance frequency clock count
52  * @tsc:   time stamp counter
53  */
54 struct amd_aperf_mperf {
55 	u64 aperf;
56 	u64 mperf;
57 	u64 tsc;
58 };
59 
60 /**
61  * struct amd_cpudata - private CPU data for AMD P-State
62  * @cpu: CPU number
63  * @req: constraint request to apply
64  * @cppc_req_cached: cached performance request hints
65  * @perf: cached performance-related data
66  * @prefcore_ranking: the preferred core ranking, the higher value indicates a higher
67  * 		  priority.
68  * @min_limit_freq: Cached value of policy->min (in khz)
69  * @max_limit_freq: Cached value of policy->max (in khz)
70  * @nominal_freq: the frequency (in khz) that mapped to nominal_perf
71  * @lowest_nonlinear_freq: the frequency (in khz) that mapped to lowest_nonlinear_perf
72  * @cur: Difference of Aperf/Mperf/tsc count between last and current sample
73  * @prev: Last Aperf/Mperf/tsc count value read from register
74  * @freq: current cpu frequency value (in khz)
75  * @boost_supported: check whether the Processor or SBIOS supports boost mode
76  * @hw_prefcore: check whether HW supports preferred core featue.
77  * 		  Only when hw_prefcore and early prefcore param are true,
78  * 		  AMD P-State driver supports preferred core featue.
79  * @epp_cached: Cached CPPC energy-performance preference value
80  * @policy: Cpufreq policy value
81  *
82  * The amd_cpudata is key private data for each CPU thread in AMD P-State, and
83  * represents all the attributes and goals that AMD P-State requests at runtime.
84  */
85 struct amd_cpudata {
86 	int	cpu;
87 
88 	struct	freq_qos_request req[2];
89 	u64	cppc_req_cached;
90 
91 	union perf_cached perf;
92 
93 	u8	prefcore_ranking;
94 	u32	min_limit_freq;
95 	u32	max_limit_freq;
96 	u32	nominal_freq;
97 	u32	lowest_nonlinear_freq;
98 
99 	struct amd_aperf_mperf cur;
100 	struct amd_aperf_mperf prev;
101 
102 	u64	freq;
103 	bool	boost_supported;
104 	bool	hw_prefcore;
105 
106 	/* EPP feature related attributes*/
107 	u32	policy;
108 	bool	suspended;
109 	u8	epp_default;
110 };
111 
112 /*
113  * enum amd_pstate_mode - driver working mode of amd pstate
114  */
115 enum amd_pstate_mode {
116 	AMD_PSTATE_UNDEFINED = 0,
117 	AMD_PSTATE_DISABLE,
118 	AMD_PSTATE_PASSIVE,
119 	AMD_PSTATE_ACTIVE,
120 	AMD_PSTATE_GUIDED,
121 	AMD_PSTATE_MAX,
122 };
123 const char *amd_pstate_get_mode_string(enum amd_pstate_mode mode);
124 int amd_pstate_get_status(void);
125 int amd_pstate_update_status(const char *buf, size_t size);
126 
127 #endif /* _LINUX_AMD_PSTATE_H */
128