drivers/bus/acpi/acpica/hardware/hwacpi.c

   1 /******************************************************************************
   2  *
   3  * Module Name: hwacpi - ACPI Hardware Initialization/Mode Interface
   4  *
   5  *****************************************************************************/
   6
   7 /******************************************************************************
   8  *
   9  * 1. Copyright Notice
  10  *
  11  * Some or all of this work - Copyright (c) 1999 - 2014, Intel Corp.
  12  * All rights reserved.
  13  *
  14  * 2. License
  15  *
  16  * 2.1. This is your license from Intel Corp. under its intellectual property
  17  * rights. You may have additional license terms from the party that provided
  18  * you this software, covering your right to use that party's intellectual
  19  * property rights.
  20  *
  21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  22  * copy of the source code appearing in this file ("Covered Code") an
  23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  24  * base code distributed originally by Intel ("Original Intel Code") to copy,
  25  * make derivatives, distribute, use and display any portion of the Covered
  26  * Code in any form, with the right to sublicense such rights; and
  27  *
  28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  29  * license (with the right to sublicense), under only those claims of Intel
  30  * patents that are infringed by the Original Intel Code, to make, use, sell,
  31  * offer to sell, and import the Covered Code and derivative works thereof
  32  * solely to the minimum extent necessary to exercise the above copyright
  33  * license, and in no event shall the patent license extend to any additions
  34  * to or modifications of the Original Intel Code. No other license or right
  35  * is granted directly or by implication, estoppel or otherwise;
  36  *
  37  * The above copyright and patent license is granted only if the following
  38  * conditions are met:
  39  *
  40  * 3. Conditions
  41  *
  42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  43  * Redistribution of source code of any substantial portion of the Covered
  44  * Code or modification with rights to further distribute source must include
  45  * the above Copyright Notice, the above License, this list of Conditions,
  46  * and the following Disclaimer and Export Compliance provision. In addition,
  47  * Licensee must cause all Covered Code to which Licensee contributes to
  48  * contain a file documenting the changes Licensee made to create that Covered
  49  * Code and the date of any change. Licensee must include in that file the
  50  * documentation of any changes made by any predecessor Licensee. Licensee
  51  * must include a prominent statement that the modification is derived,
  52  * directly or indirectly, from Original Intel Code.
  53  *
  54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  55  * Redistribution of source code of any substantial portion of the Covered
  56  * Code or modification without rights to further distribute source must
  57  * include the following Disclaimer and Export Compliance provision in the
  58  * documentation and/or other materials provided with distribution. In
  59  * addition, Licensee may not authorize further sublicense of source of any
  60  * portion of the Covered Code, and must include terms to the effect that the
  61  * license from Licensee to its licensee is limited to the intellectual
  62  * property embodied in the software Licensee provides to its licensee, and
  63  * not to intellectual property embodied in modifications its licensee may
  64  * make.
  65  *
  66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  67  * substantial portion of the Covered Code or modification must reproduce the
  68  * above Copyright Notice, and the following Disclaimer and Export Compliance
  69  * provision in the documentation and/or other materials provided with the
  70  * distribution.
  71  *
  72  * 3.4. Intel retains all right, title, and interest in and to the Original
  73  * Intel Code.
  74  *
  75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  76  * Intel shall be used in advertising or otherwise to promote the sale, use or
  77  * other dealings in products derived from or relating to the Covered Code
  78  * without prior written authorization from Intel.
  79  *
  80  * 4. Disclaimer and Export Compliance
  81  *
  82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
  85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
  86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
  87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  88  * PARTICULAR PURPOSE.
  89  *
  90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
  96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  97  * LIMITED REMEDY.
  98  *
  99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
 100  * software or system incorporating such software without first obtaining any
 101  * required license or other approval from the U. S. Department of Commerce or
 102  * any other agency or department of the United States Government. In the
 103  * event Licensee exports any such software from the United States or
 104  * re-exports any such software from a foreign destination, Licensee shall
 105  * ensure that the distribution and export/re-export of the software is in
 106  * compliance with all laws, regulations, orders, or other restrictions of the
 107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 108  * any of its subsidiaries will export/re-export any technical data, process,
 109  * software, or service, directly or indirectly, to any country for which the
 110  * United States government or any agency thereof requires an export license,
 111  * other governmental approval, or letter of assurance, without first obtaining
 112  * such license, approval or letter.
 113  *
 114  *****************************************************************************/
 115
 116 #define __HWACPI_C__
 117
 118 #include "acpi.h"
 119 #include "accommon.h"
 120
 121
 122 #define _COMPONENT          ACPI_HARDWARE
 123         ACPI_MODULE_NAME    ("hwacpi")
 124
 125
 126 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
 127 /******************************************************************************
 128  *
 129  * FUNCTION:    AcpiHwSetMode
 130  *
 131  * PARAMETERS:  Mode            - SYS_MODE_ACPI or SYS_MODE_LEGACY
 132  *
 133  * RETURN:      Status
 134  *
 135  * DESCRIPTION: Transitions the system into the requested mode.
 136  *
 137  ******************************************************************************/
 138
 139 ACPI_STATUS
 140 AcpiHwSetMode (
 141     UINT32                  Mode)
 142 {
 143
 144     ACPI_STATUS             Status;
 145     UINT32                  Retry;
 146
 147
 148     ACPI_FUNCTION_TRACE (HwSetMode);
 149
 150
 151     /* If the Hardware Reduced flag is set, machine is always in acpi mode */
 152
 153     if (AcpiGbl_ReducedHardware)
 154     {
 155         return_ACPI_STATUS (AE_OK);
 156     }
 157
 158     /*
 159      * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
 160      * system does not support mode transition.
 161      */
 162     if (!AcpiGbl_FADT.SmiCommand)
 163     {
 164         ACPI_ERROR ((AE_INFO, "No SMI_CMD in FADT, mode transition failed"));
 165         return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
 166     }
 167
 168     /*
 169      * ACPI 2.0 clarified the meaning of ACPI_ENABLE and ACPI_DISABLE
 170      * in FADT: If it is zero, enabling or disabling is not supported.
 171      * As old systems may have used zero for mode transition,
 172      * we make sure both the numbers are zero to determine these
 173      * transitions are not supported.
 174      */
 175     if (!AcpiGbl_FADT.AcpiEnable && !AcpiGbl_FADT.AcpiDisable)
 176     {
 177         ACPI_ERROR ((AE_INFO,
 178             "No ACPI mode transition supported in this system "
 179             "(enable/disable both zero)"));
 180         return_ACPI_STATUS (AE_OK);
 181     }
 182
 183     switch (Mode)
 184     {
 185     case ACPI_SYS_MODE_ACPI:
 186
 187         /* BIOS should have disabled ALL fixed and GP events */
 188
 189         Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand,
 190                         (UINT32) AcpiGbl_FADT.AcpiEnable, 8);
 191         ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Attempting to enable ACPI mode\n"));
 192         break;
 193
 194     case ACPI_SYS_MODE_LEGACY:
 195         /*
 196          * BIOS should clear all fixed status bits and restore fixed event
 197          * enable bits to default
 198          */
 199         Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand,
 200                     (UINT32) AcpiGbl_FADT.AcpiDisable, 8);
 201         ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
 202                     "Attempting to enable Legacy (non-ACPI) mode\n"));
 203         break;
 204
 205     default:
 206
 207         return_ACPI_STATUS (AE_BAD_PARAMETER);
 208     }
 209
 210     if (ACPI_FAILURE (Status))
 211     {
 212         ACPI_EXCEPTION ((AE_INFO, Status,
 213             "Could not write ACPI mode change"));
 214         return_ACPI_STATUS (Status);
 215     }
 216
 217     /*
 218      * Some hardware takes a LONG time to switch modes. Give them 3 sec to
 219      * do so, but allow faster systems to proceed more quickly.
 220      */
 221     Retry = 3000;
 222     while (Retry)
 223     {
 224         if (AcpiHwGetMode () == Mode)
 225         {
 226             ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Mode %X successfully enabled\n",
 227                 Mode));
 228             return_ACPI_STATUS (AE_OK);
 229         }
 230         AcpiOsStall (ACPI_USEC_PER_MSEC);
 231         Retry--;
 232     }
 233
 234     ACPI_ERROR ((AE_INFO, "Hardware did not change modes"));
 235     return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
 236 }
 237
 238
 239 /*******************************************************************************
 240  *
 241  * FUNCTION:    AcpiHwGetMode
 242  *
 243  * PARAMETERS:  none
 244  *
 245  * RETURN:      SYS_MODE_ACPI or SYS_MODE_LEGACY
 246  *
 247  * DESCRIPTION: Return current operating state of system. Determined by
 248  *              querying the SCI_EN bit.
 249  *
 250  ******************************************************************************/
 251
 252 UINT32
 253 AcpiHwGetMode (
 254     void)
 255 {
 256     ACPI_STATUS             Status;
 257     UINT32                  Value;
 258
 259
 260     ACPI_FUNCTION_TRACE (HwGetMode);
 261
 262
 263     /* If the Hardware Reduced flag is set, machine is always in acpi mode */
 264
 265     if (AcpiGbl_ReducedHardware)
 266     {
 267         return_UINT32 (ACPI_SYS_MODE_ACPI);
 268     }
 269
 270     /*
 271      * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
 272      * system does not support mode transition.
 273      */
 274     if (!AcpiGbl_FADT.SmiCommand)
 275     {
 276         return_UINT32 (ACPI_SYS_MODE_ACPI);
 277     }
 278
 279     Status = AcpiReadBitRegister (ACPI_BITREG_SCI_ENABLE, &Value);
 280     if (ACPI_FAILURE (Status))
 281     {
 282         return_UINT32 (ACPI_SYS_MODE_LEGACY);
 283     }
 284
 285     if (Value)
 286     {
 287         return_UINT32 (ACPI_SYS_MODE_ACPI);
 288     }
 289     else
 290     {
 291         return_UINT32 (ACPI_SYS_MODE_LEGACY);
 292     }
 293 }
 294
 295 #endif /* !ACPI_REDUCED_HARDWARE */