xref: /freebsd/contrib/processor-trace/libipt/internal/include/pt_time.h (revision 85f87cf491bec6f90948a85b10f5523ea24db9e3)
1 /*
2  * Copyright (c) 2014-2019, Intel Corporation
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  *  * Redistributions of source code must retain the above copyright notice,
8  *    this list of conditions and the following disclaimer.
9  *  * Redistributions in binary form must reproduce the above copyright notice,
10  *    this list of conditions and the following disclaimer in the documentation
11  *    and/or other materials provided with the distribution.
12  *  * Neither the name of Intel Corporation nor the names of its contributors
13  *    may be used to endorse or promote products derived from this software
14  *    without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef PT_TIME_H
30 #define PT_TIME_H
31 
32 #include <stdint.h>
33 
34 struct pt_config;
35 struct pt_packet_tsc;
36 struct pt_packet_cbr;
37 struct pt_packet_tma;
38 struct pt_packet_mtc;
39 struct pt_packet_cyc;
40 
41 
42 /* Intel(R) Processor Trace timing. */
43 struct pt_time {
44 	/* The estimated Time Stamp Count. */
45 	uint64_t tsc;
46 
47 	/* The base Time Stamp Count (from TSC and MTC). */
48 	uint64_t base;
49 
50 	/* The estimated Fast Counter. */
51 	uint64_t fc;
52 
53 	/* The adjusted last CTC value (from MTC and TMA). */
54 	uint32_t ctc;
55 
56 	/* The adjusted CTC value when @fc was cleared (from MTC and TMA). */
57 	uint32_t ctc_cyc;
58 
59 	/* The number of lost MTC updates. */
60 	uint32_t lost_mtc;
61 
62 	/* The number of lost CYC updates. */
63 	uint32_t lost_cyc;
64 
65 	/* The core:bus ratio. */
66 	uint8_t cbr;
67 
68 	/* A flag saying whether we have seen a TSC packet. */
69 	uint32_t have_tsc:1;
70 
71 	/* A flag saying whether we have seen a CBR packet. */
72 	uint32_t have_cbr:1;
73 
74 	/* A flag saying whether we have seen a TMA packet. */
75 	uint32_t have_tma:1;
76 
77 	/* A flag saying whether we have seen a MTC packet. */
78 	uint32_t have_mtc:1;
79 };
80 
81 /* Initialize (or reset) the time. */
82 extern void pt_time_init(struct pt_time *time);
83 
84 /* Query the current time.
85  *
86  * Provides the estimated Time Stamp Count value in @tsc.
87  *
88  * If @lost_mtc is not NULL, provides the number of lost MTC packets.
89  * If @lost_cyc is not NULL, provides the number of lost CYC packets.
90  *
91  * Returns zero on success; a negative error code, otherwise.
92  * Returns -pte_internal if @tsc or @time is NULL.
93  * Returns -pte_no_time if there has not been a TSC packet.
94  */
95 extern int pt_time_query_tsc(uint64_t *tsc, uint32_t *lost_mtc,
96 			     uint32_t *lost_cyc, const struct pt_time *time);
97 
98 /* Query the current core:bus ratio.
99  *
100  * Provides the core:bus ratio in @cbr.
101  *
102  * Returns zero on success; a negative error code, otherwise.
103  * Returns -pte_internal if @cbr or @time is NULL.
104  * Returns -pte_no_cbr if there has not been a CBR packet.
105  */
106 extern int pt_time_query_cbr(uint32_t *cbr, const struct pt_time *time);
107 
108 /* Update the time based on an Intel PT packet.
109  *
110  * Returns zero on success.
111  * Returns a negative error code, otherwise.
112  */
113 extern int pt_time_update_tsc(struct pt_time *, const struct pt_packet_tsc *,
114 			      const struct pt_config *);
115 extern int pt_time_update_cbr(struct pt_time *, const struct pt_packet_cbr *,
116 			      const struct pt_config *);
117 extern int pt_time_update_tma(struct pt_time *, const struct pt_packet_tma *,
118 			      const struct pt_config *);
119 extern int pt_time_update_mtc(struct pt_time *, const struct pt_packet_mtc *,
120 			      const struct pt_config *);
121 /* @fcr is the fast-counter:cycles ratio obtained by calibration. */
122 extern int pt_time_update_cyc(struct pt_time *, const struct pt_packet_cyc *,
123 			      const struct pt_config *, uint64_t fcr);
124 
125 
126 /* Timing calibration.
127  *
128  * Used for estimating the Fast-Counter:Cycles ratio.
129  *
130  * Ideally, we calibrate by counting CYCs between MTCs.  Lacking MTCs, we
131  * use TSC, instead.
132  */
133 struct pt_time_cal {
134 	/* The estimated fast-counter:cycles ratio. */
135 	uint64_t fcr;
136 
137 	/* The minimal and maximal @fcr values. */
138 	uint64_t min_fcr, max_fcr;
139 
140 	/* The last TSC value.
141 	 *
142 	 * Used for calibrating at TSC.
143 	 */
144 	uint64_t tsc;
145 
146 	/* The number of cycles since the last TSC (from CYC).
147 	 *
148 	 * Used for calibrating at TSC.
149 	 */
150 	uint64_t cyc_tsc;
151 
152 	/* The number of cycles since the last MTC (from CYC).
153 	 *
154 	 * Used for calibrating at MTC.
155 	 */
156 	uint64_t cyc_mtc;
157 
158 	/* The adjusted last CTC value (from MTC).
159 	 *
160 	 * Used for calibrating at MTC.
161 	 */
162 	uint32_t ctc;
163 
164 	/* The number of lost MTC updates since the last successful update. */
165 	uint32_t lost_mtc;
166 
167 	/* A flag saying whether we have seen a MTC packet. */
168 	uint32_t have_mtc:1;
169 
170 	/* A flag saying whether we need to check for erratum SKL168. */
171 	uint32_t check_skl168:1;
172 };
173 
174 enum {
175 	/* The amount by which the fcr value is right-shifted.
176 	 *
177 	 * Do not shift the value obtained by pt_tcal_fcr() when passing it to
178 	 * pt_time_update_cyc().
179 	 * Do shift the value passed to pt_tcal_set_fcr().
180 	 */
181 	pt_tcal_fcr_shr	= 8
182 };
183 
184 /* Initialize of reset timing calibration. */
185 extern void pt_tcal_init(struct pt_time_cal *tcal);
186 
187 /* Query the estimated fast-counter:cycles ratio.
188  *
189  * Provides the estimated ratio in @fcr unless -pte_internal or
190  * -pte_no_time is returned.
191  *
192  * Returns zero on success, a negative error code otherwise.
193  * Returns -pte_internal if @fcr or @tcal is NULL.
194  * Returns -pte_no_time if no information is available.
195  */
196 extern int pt_tcal_fcr(uint64_t *fcr, const struct pt_time_cal *tcal);
197 
198 /* Set the fast-counter:cycles ratio.
199  *
200  * Timing calibration takes one CBR or two MTC packets before it can provide
201  * first estimations.  Use this to supply an initial value to be used in the
202  * meantime.
203  *
204  * Returns zero on success, a negative error code otherwise.
205  * Returns -pte_internal if @cal is NULL.
206  */
207 extern int pt_tcal_set_fcr(struct pt_time_cal *tcal, uint64_t fcr);
208 
209 /* Update calibration based on an Intel PT packet.
210  *
211  * Returns zero on success, a negative error code otherwise.
212  */
213 extern int pt_tcal_update_tsc(struct pt_time_cal *,
214 			      const struct pt_packet_tsc *,
215 			      const struct pt_config *);
216 extern int pt_tcal_header_tsc(struct pt_time_cal *,
217 			      const struct pt_packet_tsc *,
218 			      const struct pt_config *);
219 extern int pt_tcal_update_cbr(struct pt_time_cal *,
220 			      const struct pt_packet_cbr *,
221 			      const struct pt_config *);
222 extern int pt_tcal_header_cbr(struct pt_time_cal *,
223 			      const struct pt_packet_cbr *,
224 			      const struct pt_config *);
225 extern int pt_tcal_update_tma(struct pt_time_cal *,
226 			      const struct pt_packet_tma *,
227 			      const struct pt_config *);
228 extern int pt_tcal_update_mtc(struct pt_time_cal *,
229 			      const struct pt_packet_mtc *,
230 			      const struct pt_config *);
231 extern int pt_tcal_update_cyc(struct pt_time_cal *,
232 			      const struct pt_packet_cyc *,
233 			      const struct pt_config *);
234 extern int pt_tcal_update_psb(struct pt_time_cal *,
235 			      const struct pt_config *);
236 extern int pt_tcal_update_ovf(struct pt_time_cal *,
237 			      const struct pt_config *);
238 
239 #endif /* PT_TIME_H */
240