xref: /titanic_51/usr/src/uts/intel/io/acpica/hardware/hwtimer.c (revision 5a7763bf3e9db4cfe6cb523b096cb74af71e3793)
1 
2 /******************************************************************************
3  *
4  * Name: hwtimer.c - ACPI Power Management Timer Interface
5  *              $Revision: 1.35 $
6  *
7  *****************************************************************************/
8 
9 /******************************************************************************
10  *
11  * 1. Copyright Notice
12  *
13  * Some or all of this work - Copyright (c) 1999 - 2006, Intel Corp.
14  * All rights reserved.
15  *
16  * 2. License
17  *
18  * 2.1. This is your license from Intel Corp. under its intellectual property
19  * rights.  You may have additional license terms from the party that provided
20  * you this software, covering your right to use that party's intellectual
21  * property rights.
22  *
23  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
24  * copy of the source code appearing in this file ("Covered Code") an
25  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
26  * base code distributed originally by Intel ("Original Intel Code") to copy,
27  * make derivatives, distribute, use and display any portion of the Covered
28  * Code in any form, with the right to sublicense such rights; and
29  *
30  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
31  * license (with the right to sublicense), under only those claims of Intel
32  * patents that are infringed by the Original Intel Code, to make, use, sell,
33  * offer to sell, and import the Covered Code and derivative works thereof
34  * solely to the minimum extent necessary to exercise the above copyright
35  * license, and in no event shall the patent license extend to any additions
36  * to or modifications of the Original Intel Code.  No other license or right
37  * is granted directly or by implication, estoppel or otherwise;
38  *
39  * The above copyright and patent license is granted only if the following
40  * conditions are met:
41  *
42  * 3. Conditions
43  *
44  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
45  * Redistribution of source code of any substantial portion of the Covered
46  * Code or modification with rights to further distribute source must include
47  * the above Copyright Notice, the above License, this list of Conditions,
48  * and the following Disclaimer and Export Compliance provision.  In addition,
49  * Licensee must cause all Covered Code to which Licensee contributes to
50  * contain a file documenting the changes Licensee made to create that Covered
51  * Code and the date of any change.  Licensee must include in that file the
52  * documentation of any changes made by any predecessor Licensee.  Licensee
53  * must include a prominent statement that the modification is derived,
54  * directly or indirectly, from Original Intel Code.
55  *
56  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
57  * Redistribution of source code of any substantial portion of the Covered
58  * Code or modification without rights to further distribute source must
59  * include the following Disclaimer and Export Compliance provision in the
60  * documentation and/or other materials provided with distribution.  In
61  * addition, Licensee may not authorize further sublicense of source of any
62  * portion of the Covered Code, and must include terms to the effect that the
63  * license from Licensee to its licensee is limited to the intellectual
64  * property embodied in the software Licensee provides to its licensee, and
65  * not to intellectual property embodied in modifications its licensee may
66  * make.
67  *
68  * 3.3. Redistribution of Executable. Redistribution in executable form of any
69  * substantial portion of the Covered Code or modification must reproduce the
70  * above Copyright Notice, and the following Disclaimer and Export Compliance
71  * provision in the documentation and/or other materials provided with the
72  * distribution.
73  *
74  * 3.4. Intel retains all right, title, and interest in and to the Original
75  * Intel Code.
76  *
77  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
78  * Intel shall be used in advertising or otherwise to promote the sale, use or
79  * other dealings in products derived from or relating to the Covered Code
80  * without prior written authorization from Intel.
81  *
82  * 4. Disclaimer and Export Compliance
83  *
84  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
85  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
86  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
87  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
88  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
89  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
90  * PARTICULAR PURPOSE.
91  *
92  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
93  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
94  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
95  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
96  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
97  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
98  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
99  * LIMITED REMEDY.
100  *
101  * 4.3. Licensee shall not export, either directly or indirectly, any of this
102  * software or system incorporating such software without first obtaining any
103  * required license or other approval from the U. S. Department of Commerce or
104  * any other agency or department of the United States Government.  In the
105  * event Licensee exports any such software from the United States or
106  * re-exports any such software from a foreign destination, Licensee shall
107  * ensure that the distribution and export/re-export of the software is in
108  * compliance with all laws, regulations, orders, or other restrictions of the
109  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
110  * any of its subsidiaries will export/re-export any technical data, process,
111  * software, or service, directly or indirectly, to any country for which the
112  * United States government or any agency thereof requires an export license,
113  * other governmental approval, or letter of assurance, without first obtaining
114  * such license, approval or letter.
115  *
116  *****************************************************************************/
117 
118 #include "acpi.h"
119 
120 #define _COMPONENT          ACPI_HARDWARE
121         ACPI_MODULE_NAME    ("hwtimer")
122 
123 
124 /******************************************************************************
125  *
126  * FUNCTION:    AcpiGetTimerResolution
127  *
128  * PARAMETERS:  Resolution          - Where the resolution is returned
129  *
130  * RETURN:      Status and timer resolution
131  *
132  * DESCRIPTION: Obtains resolution of the ACPI PM Timer (24 or 32 bits).
133  *
134  ******************************************************************************/
135 
136 ACPI_STATUS
137 AcpiGetTimerResolution (
138     UINT32                  *Resolution)
139 {
140     ACPI_FUNCTION_TRACE (AcpiGetTimerResolution);
141 
142 
143     if (!Resolution)
144     {
145         return_ACPI_STATUS (AE_BAD_PARAMETER);
146     }
147 
148     if (AcpiGbl_FADT->TmrValExt == 0)
149     {
150         *Resolution = 24;
151     }
152     else
153     {
154         *Resolution = 32;
155     }
156 
157     return_ACPI_STATUS (AE_OK);
158 }
159 
160 ACPI_EXPORT_SYMBOL (AcpiGetTimerResolution)
161 
162 
163 /******************************************************************************
164  *
165  * FUNCTION:    AcpiGetTimer
166  *
167  * PARAMETERS:  Ticks               - Where the timer value is returned
168  *
169  * RETURN:      Status and current timer value (ticks)
170  *
171  * DESCRIPTION: Obtains current value of ACPI PM Timer (in ticks).
172  *
173  ******************************************************************************/
174 
175 ACPI_STATUS
176 AcpiGetTimer (
177     UINT32                  *Ticks)
178 {
179     ACPI_STATUS             Status;
180 
181 
182     ACPI_FUNCTION_TRACE (AcpiGetTimer);
183 
184 
185     if (!Ticks)
186     {
187         return_ACPI_STATUS (AE_BAD_PARAMETER);
188     }
189 
190     Status = AcpiHwLowLevelRead (32, Ticks, &AcpiGbl_FADT->XPmTmrBlk);
191 
192     return_ACPI_STATUS (Status);
193 }
194 
195 ACPI_EXPORT_SYMBOL (AcpiGetTimer)
196 
197 
198 /******************************************************************************
199  *
200  * FUNCTION:    AcpiGetTimerDuration
201  *
202  * PARAMETERS:  StartTicks          - Starting timestamp
203  *              EndTicks            - End timestamp
204  *              TimeElapsed         - Where the elapsed time is returned
205  *
206  * RETURN:      Status and TimeElapsed
207  *
208  * DESCRIPTION: Computes the time elapsed (in microseconds) between two
209  *              PM Timer time stamps, taking into account the possibility of
210  *              rollovers, the timer resolution, and timer frequency.
211  *
212  *              The PM Timer's clock ticks at roughly 3.6 times per
213  *              _microsecond_, and its clock continues through Cx state
214  *              transitions (unlike many CPU timestamp counters) -- making it
215  *              a versatile and accurate timer.
216  *
217  *              Note that this function accommodates only a single timer
218  *              rollover.  Thus for 24-bit timers, this function should only
219  *              be used for calculating durations less than ~4.6 seconds
220  *              (~20 minutes for 32-bit timers) -- calculations below:
221  *
222  *              2**24 Ticks / 3,600,000 Ticks/Sec = 4.66 sec
223  *              2**32 Ticks / 3,600,000 Ticks/Sec = 1193 sec or 19.88 minutes
224  *
225  ******************************************************************************/
226 
227 ACPI_STATUS
228 AcpiGetTimerDuration (
229     UINT32                  StartTicks,
230     UINT32                  EndTicks,
231     UINT32                  *TimeElapsed)
232 {
233     ACPI_STATUS             Status;
234     UINT32                  DeltaTicks;
235     ACPI_INTEGER            Quotient;
236 
237 
238     ACPI_FUNCTION_TRACE (AcpiGetTimerDuration);
239 
240 
241     if (!TimeElapsed)
242     {
243         return_ACPI_STATUS (AE_BAD_PARAMETER);
244     }
245 
246     /*
247      * Compute Tick Delta:
248      * Handle (max one) timer rollovers on 24-bit versus 32-bit timers.
249      */
250     if (StartTicks < EndTicks)
251     {
252         DeltaTicks = EndTicks - StartTicks;
253     }
254     else if (StartTicks > EndTicks)
255     {
256         if (AcpiGbl_FADT->TmrValExt == 0)
257         {
258             /* 24-bit Timer */
259 
260             DeltaTicks = (((0x00FFFFFF - StartTicks) + EndTicks) & 0x00FFFFFF);
261         }
262         else
263         {
264             /* 32-bit Timer */
265 
266             DeltaTicks = (0xFFFFFFFF - StartTicks) + EndTicks;
267         }
268     }
269     else /* StartTicks == EndTicks */
270     {
271         *TimeElapsed = 0;
272         return_ACPI_STATUS (AE_OK);
273     }
274 
275     /*
276      * Compute Duration (Requires a 64-bit multiply and divide):
277      *
278      * TimeElapsed = (DeltaTicks * 1000000) / PM_TIMER_FREQUENCY;
279      */
280     Status = AcpiUtShortDivide (((UINT64) DeltaTicks) * 1000000,
281                 PM_TIMER_FREQUENCY, &Quotient, NULL);
282 
283     *TimeElapsed = (UINT32) Quotient;
284     return_ACPI_STATUS (Status);
285 }
286 
287 ACPI_EXPORT_SYMBOL (AcpiGetTimerDuration)
288 
289