root/drivers/acpi/acpica/hwvalid.c

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DEFINITIONS

This source file includes following definitions.
  1. acpi_hw_validate_io_request
  2. acpi_hw_read_port
  3. acpi_hw_write_port

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: hwvalid - I/O request validation
   5  *
   6  * Copyright (C) 2000 - 2019, Intel Corp.
   7  *
   8  *****************************************************************************/
   9 
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12 
  13 #define _COMPONENT          ACPI_HARDWARE
  14 ACPI_MODULE_NAME("hwvalid")
  15 
  16 /* Local prototypes */
  17 static acpi_status
  18 acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width);
  19 
  20 /*
  21  * Protected I/O ports. Some ports are always illegal, and some are
  22  * conditionally illegal. This table must remain ordered by port address.
  23  *
  24  * The table is used to implement the Microsoft port access rules that
  25  * first appeared in Windows XP. Some ports are always illegal, and some
  26  * ports are only illegal if the BIOS calls _OSI with a win_XP string or
  27  * later (meaning that the BIOS itelf is post-XP.)
  28  *
  29  * This provides ACPICA with the desired port protections and
  30  * Microsoft compatibility.
  31  *
  32  * Description of port entries:
  33  *  DMA:   DMA controller
  34  *  PIC0:  Programmable Interrupt Controller (8259A)
  35  *  PIT1:  System Timer 1
  36  *  PIT2:  System Timer 2 failsafe
  37  *  RTC:   Real-time clock
  38  *  CMOS:  Extended CMOS
  39  *  DMA1:  DMA 1 page registers
  40  *  DMA1L: DMA 1 Ch 0 low page
  41  *  DMA2:  DMA 2 page registers
  42  *  DMA2L: DMA 2 low page refresh
  43  *  ARBC:  Arbitration control
  44  *  SETUP: Reserved system board setup
  45  *  POS:   POS channel select
  46  *  PIC1:  Cascaded PIC
  47  *  IDMA:  ISA DMA
  48  *  ELCR:  PIC edge/level registers
  49  *  PCI:   PCI configuration space
  50  */
  51 static const struct acpi_port_info acpi_protected_ports[] = {
  52         {"DMA", 0x0000, 0x000F, ACPI_OSI_WIN_XP},
  53         {"PIC0", 0x0020, 0x0021, ACPI_ALWAYS_ILLEGAL},
  54         {"PIT1", 0x0040, 0x0043, ACPI_OSI_WIN_XP},
  55         {"PIT2", 0x0048, 0x004B, ACPI_OSI_WIN_XP},
  56         {"RTC", 0x0070, 0x0071, ACPI_OSI_WIN_XP},
  57         {"CMOS", 0x0074, 0x0076, ACPI_OSI_WIN_XP},
  58         {"DMA1", 0x0081, 0x0083, ACPI_OSI_WIN_XP},
  59         {"DMA1L", 0x0087, 0x0087, ACPI_OSI_WIN_XP},
  60         {"DMA2", 0x0089, 0x008B, ACPI_OSI_WIN_XP},
  61         {"DMA2L", 0x008F, 0x008F, ACPI_OSI_WIN_XP},
  62         {"ARBC", 0x0090, 0x0091, ACPI_OSI_WIN_XP},
  63         {"SETUP", 0x0093, 0x0094, ACPI_OSI_WIN_XP},
  64         {"POS", 0x0096, 0x0097, ACPI_OSI_WIN_XP},
  65         {"PIC1", 0x00A0, 0x00A1, ACPI_ALWAYS_ILLEGAL},
  66         {"IDMA", 0x00C0, 0x00DF, ACPI_OSI_WIN_XP},
  67         {"ELCR", 0x04D0, 0x04D1, ACPI_ALWAYS_ILLEGAL},
  68         {"PCI", 0x0CF8, 0x0CFF, ACPI_OSI_WIN_XP}
  69 };
  70 
  71 #define ACPI_PORT_INFO_ENTRIES      ACPI_ARRAY_LENGTH (acpi_protected_ports)
  72 
  73 /******************************************************************************
  74  *
  75  * FUNCTION:    acpi_hw_validate_io_request
  76  *
  77  * PARAMETERS:  Address             Address of I/O port/register
  78  *              bit_width           Number of bits (8,16,32)
  79  *
  80  * RETURN:      Status
  81  *
  82  * DESCRIPTION: Validates an I/O request (address/length). Certain ports are
  83  *              always illegal and some ports are only illegal depending on
  84  *              the requests the BIOS AML code makes to the predefined
  85  *              _OSI method.
  86  *
  87  ******************************************************************************/
  88 
  89 static acpi_status
  90 acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width)
  91 {
  92         u32 i;
  93         u32 byte_width;
  94         acpi_io_address last_address;
  95         const struct acpi_port_info *port_info;
  96 
  97         ACPI_FUNCTION_TRACE(hw_validate_io_request);
  98 
  99         /* Supported widths are 8/16/32 */
 100 
 101         if ((bit_width != 8) && (bit_width != 16) && (bit_width != 32)) {
 102                 ACPI_ERROR((AE_INFO,
 103                             "Bad BitWidth parameter: %8.8X", bit_width));
 104                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 105         }
 106 
 107         port_info = acpi_protected_ports;
 108         byte_width = ACPI_DIV_8(bit_width);
 109         last_address = address + byte_width - 1;
 110 
 111         ACPI_DEBUG_PRINT((ACPI_DB_IO,
 112                           "Address %8.8X%8.8X LastAddress %8.8X%8.8X Length %X",
 113                           ACPI_FORMAT_UINT64(address),
 114                           ACPI_FORMAT_UINT64(last_address), byte_width));
 115 
 116         /* Maximum 16-bit address in I/O space */
 117 
 118         if (last_address > ACPI_UINT16_MAX) {
 119                 ACPI_ERROR((AE_INFO,
 120                             "Illegal I/O port address/length above 64K: %8.8X%8.8X/0x%X",
 121                             ACPI_FORMAT_UINT64(address), byte_width));
 122                 return_ACPI_STATUS(AE_LIMIT);
 123         }
 124 
 125         /* Exit if requested address is not within the protected port table */
 126 
 127         if (address > acpi_protected_ports[ACPI_PORT_INFO_ENTRIES - 1].end) {
 128                 return_ACPI_STATUS(AE_OK);
 129         }
 130 
 131         /* Check request against the list of protected I/O ports */
 132 
 133         for (i = 0; i < ACPI_PORT_INFO_ENTRIES; i++, port_info++) {
 134                 /*
 135                  * Check if the requested address range will write to a reserved
 136                  * port. There are four cases to consider:
 137                  *
 138                  * 1) Address range is contained completely in the port address range
 139                  * 2) Address range overlaps port range at the port range start
 140                  * 3) Address range overlaps port range at the port range end
 141                  * 4) Address range completely encompasses the port range
 142                  */
 143                 if ((address <= port_info->end)
 144                     && (last_address >= port_info->start)) {
 145 
 146                         /* Port illegality may depend on the _OSI calls made by the BIOS */
 147 
 148                         if (acpi_gbl_osi_data >= port_info->osi_dependency) {
 149                                 ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
 150                                                   "Denied AML access to port 0x%8.8X%8.8X/%X (%s 0x%.4X-0x%.4X)\n",
 151                                                   ACPI_FORMAT_UINT64(address),
 152                                                   byte_width, port_info->name,
 153                                                   port_info->start,
 154                                                   port_info->end));
 155 
 156                                 return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
 157                         }
 158                 }
 159 
 160                 /* Finished if address range ends before the end of this port */
 161 
 162                 if (last_address <= port_info->end) {
 163                         break;
 164                 }
 165         }
 166 
 167         return_ACPI_STATUS(AE_OK);
 168 }
 169 
 170 /******************************************************************************
 171  *
 172  * FUNCTION:    acpi_hw_read_port
 173  *
 174  * PARAMETERS:  Address             Address of I/O port/register to read
 175  *              Value               Where value (data) is returned
 176  *              Width               Number of bits
 177  *
 178  * RETURN:      Status and value read from port
 179  *
 180  * DESCRIPTION: Read data from an I/O port or register. This is a front-end
 181  *              to acpi_os_read_port that performs validation on both the port
 182  *              address and the length.
 183  *
 184  *****************************************************************************/
 185 
 186 acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
 187 {
 188         acpi_status status;
 189         u32 one_byte;
 190         u32 i;
 191 
 192         /* Truncate address to 16 bits if requested */
 193 
 194         if (acpi_gbl_truncate_io_addresses) {
 195                 address &= ACPI_UINT16_MAX;
 196         }
 197 
 198         /* Validate the entire request and perform the I/O */
 199 
 200         status = acpi_hw_validate_io_request(address, width);
 201         if (ACPI_SUCCESS(status)) {
 202                 status = acpi_os_read_port(address, value, width);
 203                 return (status);
 204         }
 205 
 206         if (status != AE_AML_ILLEGAL_ADDRESS) {
 207                 return (status);
 208         }
 209 
 210         /*
 211          * There has been a protection violation within the request. Fall
 212          * back to byte granularity port I/O and ignore the failing bytes.
 213          * This provides compatibility with other ACPI implementations.
 214          */
 215         for (i = 0, *value = 0; i < width; i += 8) {
 216 
 217                 /* Validate and read one byte */
 218 
 219                 if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
 220                         status = acpi_os_read_port(address, &one_byte, 8);
 221                         if (ACPI_FAILURE(status)) {
 222                                 return (status);
 223                         }
 224 
 225                         *value |= (one_byte << i);
 226                 }
 227 
 228                 address++;
 229         }
 230 
 231         return (AE_OK);
 232 }
 233 
 234 /******************************************************************************
 235  *
 236  * FUNCTION:    acpi_hw_write_port
 237  *
 238  * PARAMETERS:  Address             Address of I/O port/register to write
 239  *              Value               Value to write
 240  *              Width               Number of bits
 241  *
 242  * RETURN:      Status
 243  *
 244  * DESCRIPTION: Write data to an I/O port or register. This is a front-end
 245  *              to acpi_os_write_port that performs validation on both the port
 246  *              address and the length.
 247  *
 248  *****************************************************************************/
 249 
 250 acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
 251 {
 252         acpi_status status;
 253         u32 i;
 254 
 255         /* Truncate address to 16 bits if requested */
 256 
 257         if (acpi_gbl_truncate_io_addresses) {
 258                 address &= ACPI_UINT16_MAX;
 259         }
 260 
 261         /* Validate the entire request and perform the I/O */
 262 
 263         status = acpi_hw_validate_io_request(address, width);
 264         if (ACPI_SUCCESS(status)) {
 265                 status = acpi_os_write_port(address, value, width);
 266                 return (status);
 267         }
 268 
 269         if (status != AE_AML_ILLEGAL_ADDRESS) {
 270                 return (status);
 271         }
 272 
 273         /*
 274          * There has been a protection violation within the request. Fall
 275          * back to byte granularity port I/O and ignore the failing bytes.
 276          * This provides compatibility with other ACPI implementations.
 277          */
 278         for (i = 0; i < width; i += 8) {
 279 
 280                 /* Validate and write one byte */
 281 
 282                 if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
 283                         status =
 284                             acpi_os_write_port(address, (value >> i) & 0xFF, 8);
 285                         if (ACPI_FAILURE(status)) {
 286                                 return (status);
 287                         }
 288                 }
 289 
 290                 address++;
 291         }
 292 
 293         return (AE_OK);
 294 }

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