[ACPICA] Update to version 20171215. CORE-15222
[reactos.git] / drivers / bus / acpi / acpica / hardware / hwtimer.c
1 /******************************************************************************
2 *
3 * Name: hwtimer.c - ACPI Power Management Timer Interface
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2017, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44 #define EXPORT_ACPI_INTERFACES
45
46 #include "acpi.h"
47 #include "accommon.h"
48
49 #define _COMPONENT ACPI_HARDWARE
50 ACPI_MODULE_NAME ("hwtimer")
51
52
53 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
54 /******************************************************************************
55 *
56 * FUNCTION: AcpiGetTimerResolution
57 *
58 * PARAMETERS: Resolution - Where the resolution is returned
59 *
60 * RETURN: Status and timer resolution
61 *
62 * DESCRIPTION: Obtains resolution of the ACPI PM Timer (24 or 32 bits).
63 *
64 ******************************************************************************/
65
66 ACPI_STATUS
67 AcpiGetTimerResolution (
68 UINT32 *Resolution)
69 {
70 ACPI_FUNCTION_TRACE (AcpiGetTimerResolution);
71
72
73 if (!Resolution)
74 {
75 return_ACPI_STATUS (AE_BAD_PARAMETER);
76 }
77
78 if ((AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) == 0)
79 {
80 *Resolution = 24;
81 }
82 else
83 {
84 *Resolution = 32;
85 }
86
87 return_ACPI_STATUS (AE_OK);
88 }
89
90 ACPI_EXPORT_SYMBOL (AcpiGetTimerResolution)
91
92
93 /******************************************************************************
94 *
95 * FUNCTION: AcpiGetTimer
96 *
97 * PARAMETERS: Ticks - Where the timer value is returned
98 *
99 * RETURN: Status and current timer value (ticks)
100 *
101 * DESCRIPTION: Obtains current value of ACPI PM Timer (in ticks).
102 *
103 ******************************************************************************/
104
105 ACPI_STATUS
106 AcpiGetTimer (
107 UINT32 *Ticks)
108 {
109 ACPI_STATUS Status;
110 UINT64 TimerValue;
111
112
113 ACPI_FUNCTION_TRACE (AcpiGetTimer);
114
115
116 if (!Ticks)
117 {
118 return_ACPI_STATUS (AE_BAD_PARAMETER);
119 }
120
121 /* ACPI 5.0A: PM Timer is optional */
122
123 if (!AcpiGbl_FADT.XPmTimerBlock.Address)
124 {
125 return_ACPI_STATUS (AE_SUPPORT);
126 }
127
128 Status = AcpiHwRead (&TimerValue, &AcpiGbl_FADT.XPmTimerBlock);
129 if (ACPI_SUCCESS (Status))
130 {
131 /* ACPI PM Timer is defined to be 32 bits (PM_TMR_LEN) */
132
133 *Ticks = (UINT32) TimerValue;
134 }
135
136 return_ACPI_STATUS (Status);
137 }
138
139 ACPI_EXPORT_SYMBOL (AcpiGetTimer)
140
141
142 /******************************************************************************
143 *
144 * FUNCTION: AcpiGetTimerDuration
145 *
146 * PARAMETERS: StartTicks - Starting timestamp
147 * EndTicks - End timestamp
148 * TimeElapsed - Where the elapsed time is returned
149 *
150 * RETURN: Status and TimeElapsed
151 *
152 * DESCRIPTION: Computes the time elapsed (in microseconds) between two
153 * PM Timer time stamps, taking into account the possibility of
154 * rollovers, the timer resolution, and timer frequency.
155 *
156 * The PM Timer's clock ticks at roughly 3.6 times per
157 * _microsecond_, and its clock continues through Cx state
158 * transitions (unlike many CPU timestamp counters) -- making it
159 * a versatile and accurate timer.
160 *
161 * Note that this function accommodates only a single timer
162 * rollover. Thus for 24-bit timers, this function should only
163 * be used for calculating durations less than ~4.6 seconds
164 * (~20 minutes for 32-bit timers) -- calculations below:
165 *
166 * 2**24 Ticks / 3,600,000 Ticks/Sec = 4.66 sec
167 * 2**32 Ticks / 3,600,000 Ticks/Sec = 1193 sec or 19.88 minutes
168 *
169 ******************************************************************************/
170
171 ACPI_STATUS
172 AcpiGetTimerDuration (
173 UINT32 StartTicks,
174 UINT32 EndTicks,
175 UINT32 *TimeElapsed)
176 {
177 ACPI_STATUS Status;
178 UINT64 DeltaTicks;
179 UINT64 Quotient;
180
181
182 ACPI_FUNCTION_TRACE (AcpiGetTimerDuration);
183
184
185 if (!TimeElapsed)
186 {
187 return_ACPI_STATUS (AE_BAD_PARAMETER);
188 }
189
190 /* ACPI 5.0A: PM Timer is optional */
191
192 if (!AcpiGbl_FADT.XPmTimerBlock.Address)
193 {
194 return_ACPI_STATUS (AE_SUPPORT);
195 }
196
197 if (StartTicks == EndTicks)
198 {
199 *TimeElapsed = 0;
200 return_ACPI_STATUS (AE_OK);
201 }
202
203 /*
204 * Compute Tick Delta:
205 * Handle (max one) timer rollovers on 24-bit versus 32-bit timers.
206 */
207 DeltaTicks = EndTicks;
208 if (StartTicks > EndTicks)
209 {
210 if ((AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) == 0)
211 {
212 /* 24-bit Timer */
213
214 DeltaTicks |= (UINT64) 1 << 24;
215 }
216 else
217 {
218 /* 32-bit Timer */
219
220 DeltaTicks |= (UINT64) 1 << 32;
221 }
222 }
223 DeltaTicks -= StartTicks;
224
225 /*
226 * Compute Duration (Requires a 64-bit multiply and divide):
227 *
228 * TimeElapsed (microseconds) =
229 * (DeltaTicks * ACPI_USEC_PER_SEC) / ACPI_PM_TIMER_FREQUENCY;
230 */
231 Status = AcpiUtShortDivide (DeltaTicks * ACPI_USEC_PER_SEC,
232 ACPI_PM_TIMER_FREQUENCY, &Quotient, NULL);
233
234 *TimeElapsed = (UINT32) Quotient;
235 return_ACPI_STATUS (Status);
236 }
237
238 ACPI_EXPORT_SYMBOL (AcpiGetTimerDuration)
239
240 #endif /* !ACPI_REDUCED_HARDWARE */