hwtimer.c revision 1.1.1.2.4.2
1 1.1.1.2.4.2 rmind 2 1.1.1.2.4.2 rmind /****************************************************************************** 3 1.1.1.2.4.2 rmind * 4 1.1.1.2.4.2 rmind * Name: hwtimer.c - ACPI Power Management Timer Interface 5 1.1.1.2.4.2 rmind * 6 1.1.1.2.4.2 rmind *****************************************************************************/ 7 1.1.1.2.4.2 rmind 8 1.1.1.2.4.2 rmind /* 9 1.1.1.2.4.2 rmind * Copyright (C) 2000 - 2011, Intel Corp. 10 1.1.1.2.4.2 rmind * All rights reserved. 11 1.1.1.2.4.2 rmind * 12 1.1.1.2.4.2 rmind * Redistribution and use in source and binary forms, with or without 13 1.1.1.2.4.2 rmind * modification, are permitted provided that the following conditions 14 1.1.1.2.4.2 rmind * are met: 15 1.1.1.2.4.2 rmind * 1. Redistributions of source code must retain the above copyright 16 1.1.1.2.4.2 rmind * notice, this list of conditions, and the following disclaimer, 17 1.1.1.2.4.2 rmind * without modification. 18 1.1.1.2.4.2 rmind * 2. Redistributions in binary form must reproduce at minimum a disclaimer 19 1.1.1.2.4.2 rmind * substantially similar to the "NO WARRANTY" disclaimer below 20 1.1.1.2.4.2 rmind * ("Disclaimer") and any redistribution must be conditioned upon 21 1.1.1.2.4.2 rmind * including a substantially similar Disclaimer requirement for further 22 1.1.1.2.4.2 rmind * binary redistribution. 23 1.1.1.2.4.2 rmind * 3. Neither the names of the above-listed copyright holders nor the names 24 1.1.1.2.4.2 rmind * of any contributors may be used to endorse or promote products derived 25 1.1.1.2.4.2 rmind * from this software without specific prior written permission. 26 1.1.1.2.4.2 rmind * 27 1.1.1.2.4.2 rmind * Alternatively, this software may be distributed under the terms of the 28 1.1.1.2.4.2 rmind * GNU General Public License ("GPL") version 2 as published by the Free 29 1.1.1.2.4.2 rmind * Software Foundation. 30 1.1.1.2.4.2 rmind * 31 1.1.1.2.4.2 rmind * NO WARRANTY 32 1.1.1.2.4.2 rmind * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 33 1.1.1.2.4.2 rmind * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 34 1.1.1.2.4.2 rmind * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 35 1.1.1.2.4.2 rmind * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 36 1.1.1.2.4.2 rmind * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 1.1.1.2.4.2 rmind * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 1.1.1.2.4.2 rmind * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 1.1.1.2.4.2 rmind * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 40 1.1.1.2.4.2 rmind * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 41 1.1.1.2.4.2 rmind * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 42 1.1.1.2.4.2 rmind * POSSIBILITY OF SUCH DAMAGES. 43 1.1.1.2.4.2 rmind */ 44 1.1.1.2.4.2 rmind 45 1.1.1.2.4.2 rmind #include "acpi.h" 46 1.1.1.2.4.2 rmind #include "accommon.h" 47 1.1.1.2.4.2 rmind 48 1.1.1.2.4.2 rmind #define _COMPONENT ACPI_HARDWARE 49 1.1.1.2.4.2 rmind ACPI_MODULE_NAME ("hwtimer") 50 1.1.1.2.4.2 rmind 51 1.1.1.2.4.2 rmind 52 1.1.1.2.4.2 rmind /****************************************************************************** 53 1.1.1.2.4.2 rmind * 54 1.1.1.2.4.2 rmind * FUNCTION: AcpiGetTimerResolution 55 1.1.1.2.4.2 rmind * 56 1.1.1.2.4.2 rmind * PARAMETERS: Resolution - Where the resolution is returned 57 1.1.1.2.4.2 rmind * 58 1.1.1.2.4.2 rmind * RETURN: Status and timer resolution 59 1.1.1.2.4.2 rmind * 60 1.1.1.2.4.2 rmind * DESCRIPTION: Obtains resolution of the ACPI PM Timer (24 or 32 bits). 61 1.1.1.2.4.2 rmind * 62 1.1.1.2.4.2 rmind ******************************************************************************/ 63 1.1.1.2.4.2 rmind 64 1.1.1.2.4.2 rmind ACPI_STATUS 65 1.1.1.2.4.2 rmind AcpiGetTimerResolution ( 66 1.1.1.2.4.2 rmind UINT32 *Resolution) 67 1.1.1.2.4.2 rmind { 68 1.1.1.2.4.2 rmind ACPI_FUNCTION_TRACE (AcpiGetTimerResolution); 69 1.1.1.2.4.2 rmind 70 1.1.1.2.4.2 rmind 71 1.1.1.2.4.2 rmind if (!Resolution) 72 1.1.1.2.4.2 rmind { 73 1.1.1.2.4.2 rmind return_ACPI_STATUS (AE_BAD_PARAMETER); 74 1.1.1.2.4.2 rmind } 75 1.1.1.2.4.2 rmind 76 1.1.1.2.4.2 rmind if ((AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) == 0) 77 1.1.1.2.4.2 rmind { 78 1.1.1.2.4.2 rmind *Resolution = 24; 79 1.1.1.2.4.2 rmind } 80 1.1.1.2.4.2 rmind else 81 1.1.1.2.4.2 rmind { 82 1.1.1.2.4.2 rmind *Resolution = 32; 83 1.1.1.2.4.2 rmind } 84 1.1.1.2.4.2 rmind 85 1.1.1.2.4.2 rmind return_ACPI_STATUS (AE_OK); 86 1.1.1.2.4.2 rmind } 87 1.1.1.2.4.2 rmind 88 1.1.1.2.4.2 rmind ACPI_EXPORT_SYMBOL (AcpiGetTimerResolution) 89 1.1.1.2.4.2 rmind 90 1.1.1.2.4.2 rmind 91 1.1.1.2.4.2 rmind /****************************************************************************** 92 1.1.1.2.4.2 rmind * 93 1.1.1.2.4.2 rmind * FUNCTION: AcpiGetTimer 94 1.1.1.2.4.2 rmind * 95 1.1.1.2.4.2 rmind * PARAMETERS: Ticks - Where the timer value is returned 96 1.1.1.2.4.2 rmind * 97 1.1.1.2.4.2 rmind * RETURN: Status and current timer value (ticks) 98 1.1.1.2.4.2 rmind * 99 1.1.1.2.4.2 rmind * DESCRIPTION: Obtains current value of ACPI PM Timer (in ticks). 100 1.1.1.2.4.2 rmind * 101 1.1.1.2.4.2 rmind ******************************************************************************/ 102 1.1.1.2.4.2 rmind 103 1.1.1.2.4.2 rmind ACPI_STATUS 104 1.1.1.2.4.2 rmind AcpiGetTimer ( 105 1.1.1.2.4.2 rmind UINT32 *Ticks) 106 1.1.1.2.4.2 rmind { 107 1.1.1.2.4.2 rmind ACPI_STATUS Status; 108 1.1.1.2.4.2 rmind 109 1.1.1.2.4.2 rmind 110 1.1.1.2.4.2 rmind ACPI_FUNCTION_TRACE (AcpiGetTimer); 111 1.1.1.2.4.2 rmind 112 1.1.1.2.4.2 rmind 113 1.1.1.2.4.2 rmind if (!Ticks) 114 1.1.1.2.4.2 rmind { 115 1.1.1.2.4.2 rmind return_ACPI_STATUS (AE_BAD_PARAMETER); 116 1.1.1.2.4.2 rmind } 117 1.1.1.2.4.2 rmind 118 1.1.1.2.4.2 rmind Status = AcpiHwRead (Ticks, &AcpiGbl_FADT.XPmTimerBlock); 119 1.1.1.2.4.2 rmind 120 1.1.1.2.4.2 rmind return_ACPI_STATUS (Status); 121 1.1.1.2.4.2 rmind } 122 1.1.1.2.4.2 rmind 123 1.1.1.2.4.2 rmind ACPI_EXPORT_SYMBOL (AcpiGetTimer) 124 1.1.1.2.4.2 rmind 125 1.1.1.2.4.2 rmind 126 1.1.1.2.4.2 rmind /****************************************************************************** 127 1.1.1.2.4.2 rmind * 128 1.1.1.2.4.2 rmind * FUNCTION: AcpiGetTimerDuration 129 1.1.1.2.4.2 rmind * 130 1.1.1.2.4.2 rmind * PARAMETERS: StartTicks - Starting timestamp 131 1.1.1.2.4.2 rmind * EndTicks - End timestamp 132 1.1.1.2.4.2 rmind * TimeElapsed - Where the elapsed time is returned 133 1.1.1.2.4.2 rmind * 134 1.1.1.2.4.2 rmind * RETURN: Status and TimeElapsed 135 1.1.1.2.4.2 rmind * 136 1.1.1.2.4.2 rmind * DESCRIPTION: Computes the time elapsed (in microseconds) between two 137 1.1.1.2.4.2 rmind * PM Timer time stamps, taking into account the possibility of 138 1.1.1.2.4.2 rmind * rollovers, the timer resolution, and timer frequency. 139 1.1.1.2.4.2 rmind * 140 1.1.1.2.4.2 rmind * The PM Timer's clock ticks at roughly 3.6 times per 141 1.1.1.2.4.2 rmind * _microsecond_, and its clock continues through Cx state 142 1.1.1.2.4.2 rmind * transitions (unlike many CPU timestamp counters) -- making it 143 1.1.1.2.4.2 rmind * a versatile and accurate timer. 144 1.1.1.2.4.2 rmind * 145 1.1.1.2.4.2 rmind * Note that this function accommodates only a single timer 146 1.1.1.2.4.2 rmind * rollover. Thus for 24-bit timers, this function should only 147 1.1.1.2.4.2 rmind * be used for calculating durations less than ~4.6 seconds 148 1.1.1.2.4.2 rmind * (~20 minutes for 32-bit timers) -- calculations below: 149 1.1.1.2.4.2 rmind * 150 1.1.1.2.4.2 rmind * 2**24 Ticks / 3,600,000 Ticks/Sec = 4.66 sec 151 1.1.1.2.4.2 rmind * 2**32 Ticks / 3,600,000 Ticks/Sec = 1193 sec or 19.88 minutes 152 1.1.1.2.4.2 rmind * 153 1.1.1.2.4.2 rmind ******************************************************************************/ 154 1.1.1.2.4.2 rmind 155 1.1.1.2.4.2 rmind ACPI_STATUS 156 1.1.1.2.4.2 rmind AcpiGetTimerDuration ( 157 1.1.1.2.4.2 rmind UINT32 StartTicks, 158 1.1.1.2.4.2 rmind UINT32 EndTicks, 159 1.1.1.2.4.2 rmind UINT32 *TimeElapsed) 160 1.1.1.2.4.2 rmind { 161 1.1.1.2.4.2 rmind ACPI_STATUS Status; 162 1.1.1.2.4.2 rmind UINT32 DeltaTicks; 163 1.1.1.2.4.2 rmind UINT64 Quotient; 164 1.1.1.2.4.2 rmind 165 1.1.1.2.4.2 rmind 166 1.1.1.2.4.2 rmind ACPI_FUNCTION_TRACE (AcpiGetTimerDuration); 167 1.1.1.2.4.2 rmind 168 1.1.1.2.4.2 rmind 169 1.1.1.2.4.2 rmind if (!TimeElapsed) 170 1.1.1.2.4.2 rmind { 171 1.1.1.2.4.2 rmind return_ACPI_STATUS (AE_BAD_PARAMETER); 172 1.1.1.2.4.2 rmind } 173 1.1.1.2.4.2 rmind 174 1.1.1.2.4.2 rmind /* 175 1.1.1.2.4.2 rmind * Compute Tick Delta: 176 1.1.1.2.4.2 rmind * Handle (max one) timer rollovers on 24-bit versus 32-bit timers. 177 1.1.1.2.4.2 rmind */ 178 1.1.1.2.4.2 rmind if (StartTicks < EndTicks) 179 1.1.1.2.4.2 rmind { 180 1.1.1.2.4.2 rmind DeltaTicks = EndTicks - StartTicks; 181 1.1.1.2.4.2 rmind } 182 1.1.1.2.4.2 rmind else if (StartTicks > EndTicks) 183 1.1.1.2.4.2 rmind { 184 1.1.1.2.4.2 rmind if ((AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) == 0) 185 1.1.1.2.4.2 rmind { 186 1.1.1.2.4.2 rmind /* 24-bit Timer */ 187 1.1.1.2.4.2 rmind 188 1.1.1.2.4.2 rmind DeltaTicks = (((0x00FFFFFF - StartTicks) + EndTicks) & 0x00FFFFFF); 189 1.1.1.2.4.2 rmind } 190 1.1.1.2.4.2 rmind else 191 1.1.1.2.4.2 rmind { 192 1.1.1.2.4.2 rmind /* 32-bit Timer */ 193 1.1.1.2.4.2 rmind 194 1.1.1.2.4.2 rmind DeltaTicks = (0xFFFFFFFF - StartTicks) + EndTicks; 195 1.1.1.2.4.2 rmind } 196 1.1.1.2.4.2 rmind } 197 1.1.1.2.4.2 rmind else /* StartTicks == EndTicks */ 198 1.1.1.2.4.2 rmind { 199 1.1.1.2.4.2 rmind *TimeElapsed = 0; 200 1.1.1.2.4.2 rmind return_ACPI_STATUS (AE_OK); 201 1.1.1.2.4.2 rmind } 202 1.1.1.2.4.2 rmind 203 1.1.1.2.4.2 rmind /* 204 1.1.1.2.4.2 rmind * Compute Duration (Requires a 64-bit multiply and divide): 205 1.1.1.2.4.2 rmind * 206 1.1.1.2.4.2 rmind * TimeElapsed = (DeltaTicks * 1000000) / PM_TIMER_FREQUENCY; 207 1.1.1.2.4.2 rmind */ 208 1.1.1.2.4.2 rmind Status = AcpiUtShortDivide (((UINT64) DeltaTicks) * 1000000, 209 1.1.1.2.4.2 rmind PM_TIMER_FREQUENCY, &Quotient, NULL); 210 1.1.1.2.4.2 rmind 211 1.1.1.2.4.2 rmind *TimeElapsed = (UINT32) Quotient; 212 1.1.1.2.4.2 rmind return_ACPI_STATUS (Status); 213 1.1.1.2.4.2 rmind } 214 1.1.1.2.4.2 rmind 215 1.1.1.2.4.2 rmind ACPI_EXPORT_SYMBOL (AcpiGetTimerDuration) 216 1.1.1.2.4.2 rmind 217
Indexes created Tue Sep 30 11:09:46 GMT 2025