release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/acpi/acpica/hwvalid.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: hwvalid - I/O request validation
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2010, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include "accommon.h"
  47
  48 #define _COMPONENT          ACPI_HARDWARE
  49 ACPI_MODULE_NAME("hwvalid")
  50
  51 /* Local prototypes */
  52 static acpi_status
  53 acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width);
  54
  55 /*
  56  * Protected I/O ports. Some ports are always illegal, and some are
  57  * conditionally illegal. This table must remain ordered by port address.
  58  *
  59  * The table is used to implement the Microsoft port access rules that
  60  * first appeared in Windows XP. Some ports are always illegal, and some
  61  * ports are only illegal if the BIOS calls _OSI with a win_xP string or
  62  * later (meaning that the BIOS itelf is post-XP.)
  63  *
  64  * This provides ACPICA with the desired port protections and
  65  * Microsoft compatibility.
  66  *
  67  * Description of port entries:
  68  *  DMA:   DMA controller
  69  *  PIC0:  Programmable Interrupt Controller (8259_a)
  70  *  PIT1:  System Timer 1
  71  *  PIT2:  System Timer 2 failsafe
  72  *  RTC:   Real-time clock
  73  *  CMOS:  Extended CMOS
  74  *  DMA1:  DMA 1 page registers
  75  *  DMA1L: DMA 1 Ch 0 low page
  76  *  DMA2:  DMA 2 page registers
  77  *  DMA2L: DMA 2 low page refresh
  78  *  ARBC:  Arbitration control
  79  *  SETUP: Reserved system board setup
  80  *  POS:   POS channel select
  81  *  PIC1:  Cascaded PIC
  82  *  IDMA:  ISA DMA
  83  *  ELCR:  PIC edge/level registers
  84  *  PCI:   PCI configuration space
  85  */
  86 static const struct acpi_port_info acpi_protected_ports[] = {
  87         {"DMA", 0x0000, 0x000F, ACPI_OSI_WIN_XP},
  88         {"PIC0", 0x0020, 0x0021, ACPI_ALWAYS_ILLEGAL},
  89         {"PIT1", 0x0040, 0x0043, ACPI_OSI_WIN_XP},
  90         {"PIT2", 0x0048, 0x004B, ACPI_OSI_WIN_XP},
  91         {"RTC", 0x0070, 0x0071, ACPI_OSI_WIN_XP},
  92         {"CMOS", 0x0074, 0x0076, ACPI_OSI_WIN_XP},
  93         {"DMA1", 0x0081, 0x0083, ACPI_OSI_WIN_XP},
  94         {"DMA1L", 0x0087, 0x0087, ACPI_OSI_WIN_XP},
  95         {"DMA2", 0x0089, 0x008B, ACPI_OSI_WIN_XP},
  96         {"DMA2L", 0x008F, 0x008F, ACPI_OSI_WIN_XP},
  97         {"ARBC", 0x0090, 0x0091, ACPI_OSI_WIN_XP},
  98         {"SETUP", 0x0093, 0x0094, ACPI_OSI_WIN_XP},
  99         {"POS", 0x0096, 0x0097, ACPI_OSI_WIN_XP},
 100         {"PIC1", 0x00A0, 0x00A1, ACPI_ALWAYS_ILLEGAL},
 101         {"IDMA", 0x00C0, 0x00DF, ACPI_OSI_WIN_XP},
 102         {"ELCR", 0x04D0, 0x04D1, ACPI_ALWAYS_ILLEGAL},
 103         {"PCI", 0x0CF8, 0x0CFF, ACPI_OSI_WIN_XP}
 104 };
 105
 106 #define ACPI_PORT_INFO_ENTRIES  ACPI_ARRAY_LENGTH (acpi_protected_ports)
 107
 108 /******************************************************************************
 109  *
 110  * FUNCTION:    acpi_hw_validate_io_request
 111  *
 112  * PARAMETERS:  Address             Address of I/O port/register
 113  *              bit_width           Number of bits (8,16,32)
 114  *
 115  * RETURN:      Status
 116  *
 117  * DESCRIPTION: Validates an I/O request (address/length). Certain ports are
 118  *              always illegal and some ports are only illegal depending on
 119  *              the requests the BIOS AML code makes to the predefined
 120  *              _OSI method.
 121  *
 122  ******************************************************************************/
 123
 124 static acpi_status
 125 acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width)
 126 {
 127         u32 i;
 128         u32 byte_width;
 129         acpi_io_address last_address;
 130         const struct acpi_port_info *port_info;
 131
 132         ACPI_FUNCTION_TRACE(hw_validate_io_request);
 133
 134         /* Supported widths are 8/16/32 */
 135
 136         if ((bit_width != 8) && (bit_width != 16) && (bit_width != 32)) {
 137                 return AE_BAD_PARAMETER;
 138         }
 139
 140         port_info = acpi_protected_ports;
 141         byte_width = ACPI_DIV_8(bit_width);
 142         last_address = address + byte_width - 1;
 143
 144         ACPI_DEBUG_PRINT((ACPI_DB_IO, "Address %p LastAddress %p Length %X",
 145                           ACPI_CAST_PTR(void, address), ACPI_CAST_PTR(void,
 146                                                                       last_address),
 147                           byte_width));
 148
 149         /* Maximum 16-bit address in I/O space */
 150
 151         if (last_address > ACPI_UINT16_MAX) {
 152                 ACPI_ERROR((AE_INFO,
 153                             "Illegal I/O port address/length above 64K: %p/0x%X",
 154                             ACPI_CAST_PTR(void, address), byte_width));
 155                 return_ACPI_STATUS(AE_LIMIT);
 156         }
 157
 158         /* Exit if requested address is not within the protected port table */
 159
 160         if (address > acpi_protected_ports[ACPI_PORT_INFO_ENTRIES - 1].end) {
 161                 return_ACPI_STATUS(AE_OK);
 162         }
 163
 164         /* Check request against the list of protected I/O ports */
 165
 166         for (i = 0; i < ACPI_PORT_INFO_ENTRIES; i++, port_info++) {
 167                 /*
 168                  * Check if the requested address range will write to a reserved
 169                  * port. Four cases to consider:
 170                  *
 171                  * 1) Address range is contained completely in the port address range
 172                  * 2) Address range overlaps port range at the port range start
 173                  * 3) Address range overlaps port range at the port range end
 174                  * 4) Address range completely encompasses the port range
 175                  */
 176                 if ((address <= port_info->end)
 177                     && (last_address >= port_info->start)) {
 178
 179                         /* Port illegality may depend on the _OSI calls made by the BIOS */
 180
 181                         if (acpi_gbl_osi_data >= port_info->osi_dependency) {
 182                                 ACPI_DEBUG_PRINT((ACPI_DB_IO,
 183                                                   "Denied AML access to port 0x%p/%X (%s 0x%.4X-0x%.4X)",
 184                                                   ACPI_CAST_PTR(void, address),
 185                                                   byte_width, port_info->name,
 186                                                   port_info->start,
 187                                                   port_info->end));
 188
 189                                 return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
 190                         }
 191                 }
 192
 193                 /* Finished if address range ends before the end of this port */
 194
 195                 if (last_address <= port_info->end) {
 196                         break;
 197                 }
 198         }
 199
 200         return_ACPI_STATUS(AE_OK);
 201 }
 202
 203 /******************************************************************************
 204  *
 205  * FUNCTION:    acpi_hw_read_port
 206  *
 207  * PARAMETERS:  Address             Address of I/O port/register to read
 208  *              Value               Where value is placed
 209  *              Width               Number of bits
 210  *
 211  * RETURN:      Status and value read from port
 212  *
 213  * DESCRIPTION: Read data from an I/O port or register. This is a front-end
 214  *              to acpi_os_read_port that performs validation on both the port
 215  *              address and the length.
 216  *
 217  *****************************************************************************/
 218
 219 acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
 220 {
 221         acpi_status status;
 222         u32 one_byte;
 223         u32 i;
 224
 225         /* Truncate address to 16 bits if requested */
 226
 227         if (acpi_gbl_truncate_io_addresses) {
 228                 address &= ACPI_UINT16_MAX;
 229         }
 230
 231         /* Validate the entire request and perform the I/O */
 232
 233         status = acpi_hw_validate_io_request(address, width);
 234         if (ACPI_SUCCESS(status)) {
 235                 status = acpi_os_read_port(address, value, width);
 236                 return status;
 237         }
 238
 239         if (status != AE_AML_ILLEGAL_ADDRESS) {
 240                 return status;
 241         }
 242
 243         /*
 244          * There has been a protection violation within the request. Fall
 245          * back to byte granularity port I/O and ignore the failing bytes.
 246          * This provides Windows compatibility.
 247          */
 248         for (i = 0, *value = 0; i < width; i += 8) {
 249
 250                 /* Validate and read one byte */
 251
 252                 if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
 253                         status = acpi_os_read_port(address, &one_byte, 8);
 254                         if (ACPI_FAILURE(status)) {
 255                                 return status;
 256                         }
 257
 258                         *value |= (one_byte << i);
 259                 }
 260
 261                 address++;
 262         }
 263
 264         return AE_OK;
 265 }
 266
 267 /******************************************************************************
 268  *
 269  * FUNCTION:    acpi_hw_write_port
 270  *
 271  * PARAMETERS:  Address             Address of I/O port/register to write
 272  *              Value               Value to write
 273  *              Width               Number of bits
 274  *
 275  * RETURN:      Status
 276  *
 277  * DESCRIPTION: Write data to an I/O port or register. This is a front-end
 278  *              to acpi_os_write_port that performs validation on both the port
 279  *              address and the length.
 280  *
 281  *****************************************************************************/
 282
 283 acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
 284 {
 285         acpi_status status;
 286         u32 i;
 287
 288         /* Truncate address to 16 bits if requested */
 289
 290         if (acpi_gbl_truncate_io_addresses) {
 291                 address &= ACPI_UINT16_MAX;
 292         }
 293
 294         /* Validate the entire request and perform the I/O */
 295
 296         status = acpi_hw_validate_io_request(address, width);
 297         if (ACPI_SUCCESS(status)) {
 298                 status = acpi_os_write_port(address, value, width);
 299                 return status;
 300         }
 301
 302         if (status != AE_AML_ILLEGAL_ADDRESS) {
 303                 return status;
 304         }
 305
 306         /*
 307          * There has been a protection violation within the request. Fall
 308          * back to byte granularity port I/O and ignore the failing bytes.
 309          * This provides Windows compatibility.
 310          */
 311         for (i = 0; i < width; i += 8) {
 312
 313                 /* Validate and write one byte */
 314
 315                 if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
 316                         status =
 317                             acpi_os_write_port(address, (value >> i) & 0xFF, 8);
 318                         if (ACPI_FAILURE(status)) {
 319                                 return status;
 320                         }
 321                 }
 322
 323                 address++;
 324         }
 325
 326         return AE_OK;
 327 }