xref: /openbmc/linux/drivers/acpi/acpica/hwvalid.c (revision 8a26af30)
1 /******************************************************************************
2  *
3  * Module Name: hwvalid - I/O request validation
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2014, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 
47 #define _COMPONENT          ACPI_HARDWARE
48 ACPI_MODULE_NAME("hwvalid")
49 
50 /* Local prototypes */
51 static acpi_status
52 acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width);
53 
54 /*
55  * Protected I/O ports. Some ports are always illegal, and some are
56  * conditionally illegal. This table must remain ordered by port address.
57  *
58  * The table is used to implement the Microsoft port access rules that
59  * first appeared in Windows XP. Some ports are always illegal, and some
60  * ports are only illegal if the BIOS calls _OSI with a win_XP string or
61  * later (meaning that the BIOS itelf is post-XP.)
62  *
63  * This provides ACPICA with the desired port protections and
64  * Microsoft compatibility.
65  *
66  * Description of port entries:
67  *  DMA:   DMA controller
68  *  PIC0:  Programmable Interrupt Controller (8259A)
69  *  PIT1:  System Timer 1
70  *  PIT2:  System Timer 2 failsafe
71  *  RTC:   Real-time clock
72  *  CMOS:  Extended CMOS
73  *  DMA1:  DMA 1 page registers
74  *  DMA1L: DMA 1 Ch 0 low page
75  *  DMA2:  DMA 2 page registers
76  *  DMA2L: DMA 2 low page refresh
77  *  ARBC:  Arbitration control
78  *  SETUP: Reserved system board setup
79  *  POS:   POS channel select
80  *  PIC1:  Cascaded PIC
81  *  IDMA:  ISA DMA
82  *  ELCR:  PIC edge/level registers
83  *  PCI:   PCI configuration space
84  */
85 static const struct acpi_port_info acpi_protected_ports[] = {
86 	{"DMA", 0x0000, 0x000F, ACPI_OSI_WIN_XP},
87 	{"PIC0", 0x0020, 0x0021, ACPI_ALWAYS_ILLEGAL},
88 	{"PIT1", 0x0040, 0x0043, ACPI_OSI_WIN_XP},
89 	{"PIT2", 0x0048, 0x004B, ACPI_OSI_WIN_XP},
90 	{"RTC", 0x0070, 0x0071, ACPI_OSI_WIN_XP},
91 	{"CMOS", 0x0074, 0x0076, ACPI_OSI_WIN_XP},
92 	{"DMA1", 0x0081, 0x0083, ACPI_OSI_WIN_XP},
93 	{"DMA1L", 0x0087, 0x0087, ACPI_OSI_WIN_XP},
94 	{"DMA2", 0x0089, 0x008B, ACPI_OSI_WIN_XP},
95 	{"DMA2L", 0x008F, 0x008F, ACPI_OSI_WIN_XP},
96 	{"ARBC", 0x0090, 0x0091, ACPI_OSI_WIN_XP},
97 	{"SETUP", 0x0093, 0x0094, ACPI_OSI_WIN_XP},
98 	{"POS", 0x0096, 0x0097, ACPI_OSI_WIN_XP},
99 	{"PIC1", 0x00A0, 0x00A1, ACPI_ALWAYS_ILLEGAL},
100 	{"IDMA", 0x00C0, 0x00DF, ACPI_OSI_WIN_XP},
101 	{"ELCR", 0x04D0, 0x04D1, ACPI_ALWAYS_ILLEGAL},
102 	{"PCI", 0x0CF8, 0x0CFF, ACPI_OSI_WIN_XP}
103 };
104 
105 #define ACPI_PORT_INFO_ENTRIES  ACPI_ARRAY_LENGTH (acpi_protected_ports)
106 
107 /******************************************************************************
108  *
109  * FUNCTION:    acpi_hw_validate_io_request
110  *
111  * PARAMETERS:  Address             Address of I/O port/register
112  *              bit_width           Number of bits (8,16,32)
113  *
114  * RETURN:      Status
115  *
116  * DESCRIPTION: Validates an I/O request (address/length). Certain ports are
117  *              always illegal and some ports are only illegal depending on
118  *              the requests the BIOS AML code makes to the predefined
119  *              _OSI method.
120  *
121  ******************************************************************************/
122 
123 static acpi_status
124 acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width)
125 {
126 	u32 i;
127 	u32 byte_width;
128 	acpi_io_address last_address;
129 	const struct acpi_port_info *port_info;
130 
131 	ACPI_FUNCTION_TRACE(hw_validate_io_request);
132 
133 	/* Supported widths are 8/16/32 */
134 
135 	if ((bit_width != 8) && (bit_width != 16) && (bit_width != 32)) {
136 		ACPI_ERROR((AE_INFO,
137 			    "Bad BitWidth parameter: %8.8X", bit_width));
138 		return (AE_BAD_PARAMETER);
139 	}
140 
141 	port_info = acpi_protected_ports;
142 	byte_width = ACPI_DIV_8(bit_width);
143 	last_address = address + byte_width - 1;
144 
145 	ACPI_DEBUG_PRINT((ACPI_DB_IO, "Address %p LastAddress %p Length %X",
146 			  ACPI_CAST_PTR(void, address), ACPI_CAST_PTR(void,
147 								      last_address),
148 			  byte_width));
149 
150 	/* Maximum 16-bit address in I/O space */
151 
152 	if (last_address > ACPI_UINT16_MAX) {
153 		ACPI_ERROR((AE_INFO,
154 			    "Illegal I/O port address/length above 64K: %p/0x%X",
155 			    ACPI_CAST_PTR(void, address), byte_width));
156 		return_ACPI_STATUS(AE_LIMIT);
157 	}
158 
159 	/* Exit if requested address is not within the protected port table */
160 
161 	if (address > acpi_protected_ports[ACPI_PORT_INFO_ENTRIES - 1].end) {
162 		return_ACPI_STATUS(AE_OK);
163 	}
164 
165 	/* Check request against the list of protected I/O ports */
166 
167 	for (i = 0; i < ACPI_PORT_INFO_ENTRIES; i++, port_info++) {
168 		/*
169 		 * Check if the requested address range will write to a reserved
170 		 * port. Four cases to consider:
171 		 *
172 		 * 1) Address range is contained completely in the port address range
173 		 * 2) Address range overlaps port range at the port range start
174 		 * 3) Address range overlaps port range at the port range end
175 		 * 4) Address range completely encompasses the port range
176 		 */
177 		if ((address <= port_info->end)
178 		    && (last_address >= port_info->start)) {
179 
180 			/* Port illegality may depend on the _OSI calls made by the BIOS */
181 
182 			if (acpi_gbl_osi_data >= port_info->osi_dependency) {
183 				ACPI_DEBUG_PRINT((ACPI_DB_IO,
184 						  "Denied AML access to port 0x%p/%X (%s 0x%.4X-0x%.4X)",
185 						  ACPI_CAST_PTR(void, address),
186 						  byte_width, port_info->name,
187 						  port_info->start,
188 						  port_info->end));
189 
190 				return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
191 			}
192 		}
193 
194 		/* Finished if address range ends before the end of this port */
195 
196 		if (last_address <= port_info->end) {
197 			break;
198 		}
199 	}
200 
201 	return_ACPI_STATUS(AE_OK);
202 }
203 
204 /******************************************************************************
205  *
206  * FUNCTION:    acpi_hw_read_port
207  *
208  * PARAMETERS:  Address             Address of I/O port/register to read
209  *              Value               Where value is placed
210  *              Width               Number of bits
211  *
212  * RETURN:      Status and value read from port
213  *
214  * DESCRIPTION: Read data from an I/O port or register. This is a front-end
215  *              to acpi_os_read_port that performs validation on both the port
216  *              address and the length.
217  *
218  *****************************************************************************/
219 
220 acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
221 {
222 	acpi_status status;
223 	u32 one_byte;
224 	u32 i;
225 
226 	/* Truncate address to 16 bits if requested */
227 
228 	if (acpi_gbl_truncate_io_addresses) {
229 		address &= ACPI_UINT16_MAX;
230 	}
231 
232 	/* Validate the entire request and perform the I/O */
233 
234 	status = acpi_hw_validate_io_request(address, width);
235 	if (ACPI_SUCCESS(status)) {
236 		status = acpi_os_read_port(address, value, width);
237 		return (status);
238 	}
239 
240 	if (status != AE_AML_ILLEGAL_ADDRESS) {
241 		return (status);
242 	}
243 
244 	/*
245 	 * There has been a protection violation within the request. Fall
246 	 * back to byte granularity port I/O and ignore the failing bytes.
247 	 * This provides Windows compatibility.
248 	 */
249 	for (i = 0, *value = 0; i < width; i += 8) {
250 
251 		/* Validate and read one byte */
252 
253 		if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
254 			status = acpi_os_read_port(address, &one_byte, 8);
255 			if (ACPI_FAILURE(status)) {
256 				return (status);
257 			}
258 
259 			*value |= (one_byte << i);
260 		}
261 
262 		address++;
263 	}
264 
265 	return (AE_OK);
266 }
267 
268 /******************************************************************************
269  *
270  * FUNCTION:    acpi_hw_write_port
271  *
272  * PARAMETERS:  Address             Address of I/O port/register to write
273  *              Value               Value to write
274  *              Width               Number of bits
275  *
276  * RETURN:      Status
277  *
278  * DESCRIPTION: Write data to an I/O port or register. This is a front-end
279  *              to acpi_os_write_port that performs validation on both the port
280  *              address and the length.
281  *
282  *****************************************************************************/
283 
284 acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
285 {
286 	acpi_status status;
287 	u32 i;
288 
289 	/* Truncate address to 16 bits if requested */
290 
291 	if (acpi_gbl_truncate_io_addresses) {
292 		address &= ACPI_UINT16_MAX;
293 	}
294 
295 	/* Validate the entire request and perform the I/O */
296 
297 	status = acpi_hw_validate_io_request(address, width);
298 	if (ACPI_SUCCESS(status)) {
299 		status = acpi_os_write_port(address, value, width);
300 		return (status);
301 	}
302 
303 	if (status != AE_AML_ILLEGAL_ADDRESS) {
304 		return (status);
305 	}
306 
307 	/*
308 	 * There has been a protection violation within the request. Fall
309 	 * back to byte granularity port I/O and ignore the failing bytes.
310 	 * This provides Windows compatibility.
311 	 */
312 	for (i = 0; i < width; i += 8) {
313 
314 		/* Validate and write one byte */
315 
316 		if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
317 			status =
318 			    acpi_os_write_port(address, (value >> i) & 0xFF, 8);
319 			if (ACPI_FAILURE(status)) {
320 				return (status);
321 			}
322 		}
323 
324 		address++;
325 	}
326 
327 	return (AE_OK);
328 }
329