git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/acpica/hwregs.c

   1
   2 /*******************************************************************************
   3  *
   4  * Module Name: hwregs - Read/write access functions for the various ACPI
   5  *                       control and status registers.
   6  *
   7  ******************************************************************************/
   8
   9 /*
  10  * Copyright (C) 2000 - 2008, Intel Corp.
  11  * All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions, and the following disclaimer,
  18  *    without modification.
  19  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  20  *    substantially similar to the "NO WARRANTY" disclaimer below
  21  *    ("Disclaimer") and any redistribution must be conditioned upon
  22  *    including a substantially similar Disclaimer requirement for further
  23  *    binary redistribution.
  24  * 3. Neither the names of the above-listed copyright holders nor the names
  25  *    of any contributors may be used to endorse or promote products derived
  26  *    from this software without specific prior written permission.
  27  *
  28  * Alternatively, this software may be distributed under the terms of the
  29  * GNU General Public License ("GPL") version 2 as published by the Free
  30  * Software Foundation.
  31  *
  32  * NO WARRANTY
  33  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  34  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  35  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  36  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  37  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  38  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  39  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  40  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  42  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  43  * POSSIBILITY OF SUCH DAMAGES.
  44  */
  45
  46 #include <acpi/acpi.h>
  47 #include "accommon.h"
  48 #include "acnamesp.h"
  49 #include "acevents.h"
  50
  51 #define _COMPONENT          ACPI_HARDWARE
  52 ACPI_MODULE_NAME("hwregs")
  53
  54 /* Local Prototypes */
  55 static acpi_status
  56 acpi_hw_read_multiple(u32 *value,
  57                       struct acpi_generic_address *register_a,
  58                       struct acpi_generic_address *register_b);
  59
  60 static acpi_status
  61 acpi_hw_write_multiple(u32 value,
  62                        struct acpi_generic_address *register_a,
  63                        struct acpi_generic_address *register_b);
  64
  65 /*******************************************************************************
  66  *
  67  * FUNCTION:    acpi_hw_clear_acpi_status
  68  *
  69  * PARAMETERS:  None
  70  *
  71  * RETURN:      Status
  72  *
  73  * DESCRIPTION: Clears all fixed and general purpose status bits
  74  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
  75  *
  76  ******************************************************************************/
  77
  78 acpi_status acpi_hw_clear_acpi_status(void)
  79 {
  80         acpi_status status;
  81         acpi_cpu_flags lock_flags = 0;
  82
  83         ACPI_FUNCTION_TRACE(hw_clear_acpi_status);
  84
  85         ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %04X\n",
  86                           ACPI_BITMASK_ALL_FIXED_STATUS,
  87                           (u16) acpi_gbl_xpm1a_status.address));
  88
  89         lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
  90
  91         /* Clear the fixed events */
  92
  93         status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
  94                                         ACPI_BITMASK_ALL_FIXED_STATUS);
  95         if (ACPI_FAILURE(status)) {
  96                 goto unlock_and_exit;
  97         }
  98
  99         /* Write PM1B register if present */
 100
 101         if (acpi_gbl_xpm1b_status.address) {
 102                 status = acpi_write(ACPI_BITMASK_ALL_FIXED_STATUS,
 103                                     &acpi_gbl_xpm1b_status);
 104                 if (ACPI_FAILURE(status)) {
 105                         goto unlock_and_exit;
 106                 }
 107         }
 108
 109         /* Clear the GPE Bits in all GPE registers in all GPE blocks */
 110
 111         status = acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block, NULL);
 112
 113       unlock_and_exit:
 114         acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
 115         return_ACPI_STATUS(status);
 116 }
 117
 118 /*******************************************************************************
 119  *
 120  * FUNCTION:    acpi_hw_get_register_bit_mask
 121  *
 122  * PARAMETERS:  register_id         - Index of ACPI Register to access
 123  *
 124  * RETURN:      The bitmask to be used when accessing the register
 125  *
 126  * DESCRIPTION: Map register_id into a register bitmask.
 127  *
 128  ******************************************************************************/
 129
 130 struct acpi_bit_register_info *acpi_hw_get_bit_register_info(u32 register_id)
 131 {
 132         ACPI_FUNCTION_ENTRY();
 133
 134         if (register_id > ACPI_BITREG_MAX) {
 135                 ACPI_ERROR((AE_INFO, "Invalid BitRegister ID: %X",
 136                             register_id));
 137                 return (NULL);
 138         }
 139
 140         return (&acpi_gbl_bit_register_info[register_id]);
 141 }
 142
 143 /******************************************************************************
 144  *
 145  * FUNCTION:    acpi_hw_register_read
 146  *
 147  * PARAMETERS:  register_id         - ACPI Register ID
 148  *              return_value        - Where the register value is returned
 149  *
 150  * RETURN:      Status and the value read.
 151  *
 152  * DESCRIPTION: Read from the specified ACPI register
 153  *
 154  ******************************************************************************/
 155 acpi_status
 156 acpi_hw_register_read(u32 register_id, u32 * return_value)
 157 {
 158         u32 value = 0;
 159         acpi_status status;
 160
 161         ACPI_FUNCTION_TRACE(hw_register_read);
 162
 163         switch (register_id) {
 164         case ACPI_REGISTER_PM1_STATUS:  /* PM1 A/B: 16-bit access each */
 165
 166                 status = acpi_hw_read_multiple(&value,
 167                                                &acpi_gbl_xpm1a_status,
 168                                                &acpi_gbl_xpm1b_status);
 169                 break;
 170
 171         case ACPI_REGISTER_PM1_ENABLE:  /* PM1 A/B: 16-bit access each */
 172
 173                 status = acpi_hw_read_multiple(&value,
 174                                                &acpi_gbl_xpm1a_enable,
 175                                                &acpi_gbl_xpm1b_enable);
 176                 break;
 177
 178         case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */
 179
 180                 status = acpi_hw_read_multiple(&value,
 181                                                &acpi_gbl_FADT.
 182                                                xpm1a_control_block,
 183                                                &acpi_gbl_FADT.
 184                                                xpm1b_control_block);
 185                 break;
 186
 187         case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
 188
 189                 status = acpi_read(&value, &acpi_gbl_FADT.xpm2_control_block);
 190                 break;
 191
 192         case ACPI_REGISTER_PM_TIMER:    /* 32-bit access */
 193
 194                 status = acpi_read(&value, &acpi_gbl_FADT.xpm_timer_block);
 195                 break;
 196
 197         case ACPI_REGISTER_SMI_COMMAND_BLOCK:   /* 8-bit access */
 198
 199                 status =
 200                     acpi_os_read_port(acpi_gbl_FADT.smi_command, &value, 8);
 201                 break;
 202
 203         default:
 204                 ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
 205                 status = AE_BAD_PARAMETER;
 206                 break;
 207         }
 208
 209         if (ACPI_SUCCESS(status)) {
 210                 *return_value = value;
 211         }
 212
 213         return_ACPI_STATUS(status);
 214 }
 215
 216 /******************************************************************************
 217  *
 218  * FUNCTION:    acpi_hw_register_write
 219  *
 220  * PARAMETERS:  register_id         - ACPI Register ID
 221  *              Value               - The value to write
 222  *
 223  * RETURN:      Status
 224  *
 225  * DESCRIPTION: Write to the specified ACPI register
 226  *
 227  * NOTE: In accordance with the ACPI specification, this function automatically
 228  * preserves the value of the following bits, meaning that these bits cannot be
 229  * changed via this interface:
 230  *
 231  * PM1_CONTROL[0] = SCI_EN
 232  * PM1_CONTROL[9]
 233  * PM1_STATUS[11]
 234  *
 235  * ACPI References:
 236  * 1) Hardware Ignored Bits: When software writes to a register with ignored
 237  *      bit fields, it preserves the ignored bit fields
 238  * 2) SCI_EN: OSPM always preserves this bit position
 239  *
 240  ******************************************************************************/
 241
 242 acpi_status acpi_hw_register_write(u32 register_id, u32 value)
 243 {
 244         acpi_status status;
 245         u32 read_value;
 246
 247         ACPI_FUNCTION_TRACE(hw_register_write);
 248
 249         switch (register_id) {
 250         case ACPI_REGISTER_PM1_STATUS:  /* PM1 A/B: 16-bit access each */
 251
 252                 /* Perform a read first to preserve certain bits (per ACPI spec) */
 253
 254                 status = acpi_hw_read_multiple(&read_value,
 255                                                &acpi_gbl_xpm1a_status,
 256                                                &acpi_gbl_xpm1b_status);
 257                 if (ACPI_FAILURE(status)) {
 258                         goto exit;
 259                 }
 260
 261                 /* Insert the bits to be preserved */
 262
 263                 ACPI_INSERT_BITS(value, ACPI_PM1_STATUS_PRESERVED_BITS,
 264                                  read_value);
 265
 266                 /* Now we can write the data */
 267
 268                 status = acpi_hw_write_multiple(value,
 269                                                 &acpi_gbl_xpm1a_status,
 270                                                 &acpi_gbl_xpm1b_status);
 271                 break;
 272
 273         case ACPI_REGISTER_PM1_ENABLE:  /* PM1 A/B: 16-bit access */
 274
 275                 status = acpi_hw_write_multiple(value,
 276                                                 &acpi_gbl_xpm1a_enable,
 277                                                 &acpi_gbl_xpm1b_enable);
 278                 break;
 279
 280         case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */
 281
 282                 /*
 283                  * Perform a read first to preserve certain bits (per ACPI spec)
 284                  * Note: This includes SCI_EN, we never want to change this bit
 285                  */
 286                 status = acpi_hw_read_multiple(&read_value,
 287                                                &acpi_gbl_FADT.
 288                                                xpm1a_control_block,
 289                                                &acpi_gbl_FADT.
 290                                                xpm1b_control_block);
 291                 if (ACPI_FAILURE(status)) {
 292                         goto exit;
 293                 }
 294
 295                 /* Insert the bits to be preserved */
 296
 297                 ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS,
 298                                  read_value);
 299
 300                 /* Now we can write the data */
 301
 302                 status = acpi_hw_write_multiple(value,
 303                                                 &acpi_gbl_FADT.
 304                                                 xpm1a_control_block,
 305                                                 &acpi_gbl_FADT.
 306                                                 xpm1b_control_block);
 307                 break;
 308
 309         case ACPI_REGISTER_PM1A_CONTROL:        /* 16-bit access */
 310
 311                 status = acpi_write(value, &acpi_gbl_FADT.xpm1a_control_block);
 312                 break;
 313
 314         case ACPI_REGISTER_PM1B_CONTROL:        /* 16-bit access */
 315
 316                 status = acpi_write(value, &acpi_gbl_FADT.xpm1b_control_block);
 317                 break;
 318
 319         case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
 320
 321                 status = acpi_write(value, &acpi_gbl_FADT.xpm2_control_block);
 322                 break;
 323
 324         case ACPI_REGISTER_PM_TIMER:    /* 32-bit access */
 325
 326                 status = acpi_write(value, &acpi_gbl_FADT.xpm_timer_block);
 327                 break;
 328
 329         case ACPI_REGISTER_SMI_COMMAND_BLOCK:   /* 8-bit access */
 330
 331                 /* SMI_CMD is currently always in IO space */
 332
 333                 status =
 334                     acpi_os_write_port(acpi_gbl_FADT.smi_command, value, 8);
 335                 break;
 336
 337         default:
 338                 ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
 339                 status = AE_BAD_PARAMETER;
 340                 break;
 341         }
 342
 343       exit:
 344         return_ACPI_STATUS(status);
 345 }
 346
 347 /******************************************************************************
 348  *
 349  * FUNCTION:    acpi_hw_read_multiple
 350  *
 351  * PARAMETERS:  Value               - Where the register value is returned
 352  *              register_a           - First ACPI register (required)
 353  *              register_b           - Second ACPI register (optional)
 354  *
 355  * RETURN:      Status
 356  *
 357  * DESCRIPTION: Read from the specified two-part ACPI register (such as PM1 A/B)
 358  *
 359  ******************************************************************************/
 360
 361 static acpi_status
 362 acpi_hw_read_multiple(u32 *value,
 363                       struct acpi_generic_address *register_a,
 364                       struct acpi_generic_address *register_b)
 365 {
 366         u32 value_a = 0;
 367         u32 value_b = 0;
 368         acpi_status status;
 369
 370         /* The first register is always required */
 371
 372         status = acpi_read(&value_a, register_a);
 373         if (ACPI_FAILURE(status)) {
 374                 return (status);
 375         }
 376
 377         /* Second register is optional */
 378
 379         if (register_b->address) {
 380                 status = acpi_read(&value_b, register_b);
 381                 if (ACPI_FAILURE(status)) {
 382                         return (status);
 383                 }
 384         }
 385
 386         /* Shift the B bits above the A bits */
 387
 388         *value = value_a | (value_b << register_a->bit_width);
 389         return (AE_OK);
 390 }
 391
 392 /******************************************************************************
 393  *
 394  * FUNCTION:    acpi_hw_write_multiple
 395  *
 396  * PARAMETERS:  Value               - The value to write
 397  *              register_a           - First ACPI register (required)
 398  *              register_b           - Second ACPI register (optional)
 399  *
 400  * RETURN:      Status
 401  *
 402  * DESCRIPTION: Write to the specified two-part ACPI register (such as PM1 A/B)
 403  *
 404  ******************************************************************************/
 405
 406 static acpi_status
 407 acpi_hw_write_multiple(u32 value,
 408                        struct acpi_generic_address *register_a,
 409                        struct acpi_generic_address *register_b)
 410 {
 411         acpi_status status;
 412
 413         /* The first register is always required */
 414
 415         status = acpi_write(value, register_a);
 416         if (ACPI_FAILURE(status)) {
 417                 return (status);
 418         }
 419
 420         /* Second register is optional */
 421
 422         if (register_b->address) {
 423
 424                 /* Normalize the B bits before write */
 425
 426                 status = acpi_write(value >> register_a->bit_width, register_b);
 427         }
 428
 429         return (status);
 430 }