ACPI x86: Make aperf/mperf MSR access in acpi_cpufreq read_only
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / hwvalid.c
1
2 /******************************************************************************
3  *
4  * Module Name: hwvalid - I/O request validation
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2009, 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: 0x%p/%X",
154                             ACPI_CAST_PTR(void, address), byte_width));
155                 return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
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_ERROR((AE_INFO,
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, port_info->end));
187
188                                 return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
189                         }
190                 }
191
192                 /* Finished if address range ends before the end of this port */
193
194                 if (last_address <= port_info->end) {
195                         break;
196                 }
197         }
198
199         return_ACPI_STATUS(AE_OK);
200 }
201
202 /******************************************************************************
203  *
204  * FUNCTION:    acpi_hw_read_port
205  *
206  * PARAMETERS:  Address             Address of I/O port/register to read
207  *              Value               Where value is placed
208  *              Width               Number of bits
209  *
210  * RETURN:      Value read from port
211  *
212  * DESCRIPTION: Read data from an I/O port or register. This is a front-end
213  *              to acpi_os_read_port that performs validation on both the port
214  *              address and the length.
215  *
216  *****************************************************************************/
217
218 acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
219 {
220         acpi_status status;
221
222         status = acpi_hw_validate_io_request(address, width);
223         if (ACPI_FAILURE(status)) {
224                 return status;
225         }
226
227         status = acpi_os_read_port(address, value, width);
228         return status;
229 }
230
231 /******************************************************************************
232  *
233  * FUNCTION:    acpi_hw_write_port
234  *
235  * PARAMETERS:  Address             Address of I/O port/register to write
236  *              Value               Value to write
237  *              Width               Number of bits
238  *
239  * RETURN:      None
240  *
241  * DESCRIPTION: Write data to an I/O port or register. This is a front-end
242  *              to acpi_os_write_port that performs validation on both the port
243  *              address and the length.
244  *
245  *****************************************************************************/
246
247 acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
248 {
249         acpi_status status;
250
251         status = acpi_hw_validate_io_request(address, width);
252         if (ACPI_FAILURE(status)) {
253                 return status;
254         }
255
256         status = acpi_os_write_port(address, value, width);
257         return status;
258 }