1
2/******************************************************************************
3 *
4 * Module Name: hwvalid - I/O request validation
5 *
6 *****************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2012, 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
49ACPI_MODULE_NAME("hwvalid")
50
51/* Local prototypes */
52static acpi_status
53acpi_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 */
86static 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
124static acpi_status
125acpi_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		ACPI_ERROR((AE_INFO,
138			    "Bad BitWidth parameter: %8.8X", bit_width));
139		return AE_BAD_PARAMETER;
140	}
141
142	port_info = acpi_protected_ports;
143	byte_width = ACPI_DIV_8(bit_width);
144	last_address = address + byte_width - 1;
145
146	ACPI_DEBUG_PRINT((ACPI_DB_IO, "Address %p LastAddress %p Length %X",
147			  ACPI_CAST_PTR(void, address), ACPI_CAST_PTR(void,
148								      last_address),
149			  byte_width));
150
151	/* Maximum 16-bit address in I/O space */
152
153	if (last_address > ACPI_UINT16_MAX) {
154		ACPI_ERROR((AE_INFO,
155			    "Illegal I/O port address/length above 64K: %p/0x%X",
156			    ACPI_CAST_PTR(void, address), byte_width));
157		return_ACPI_STATUS(AE_LIMIT);
158	}
159
160	/* Exit if requested address is not within the protected port table */
161
162	if (address > acpi_protected_ports[ACPI_PORT_INFO_ENTRIES - 1].end) {
163		return_ACPI_STATUS(AE_OK);
164	}
165
166	/* Check request against the list of protected I/O ports */
167
168	for (i = 0; i < ACPI_PORT_INFO_ENTRIES; i++, port_info++) {
169		/*
170		 * Check if the requested address range will write to a reserved
171		 * port. Four cases to consider:
172		 *
173		 * 1) Address range is contained completely in the port address range
174		 * 2) Address range overlaps port range at the port range start
175		 * 3) Address range overlaps port range at the port range end
176		 * 4) Address range completely encompasses the port range
177		 */
178		if ((address <= port_info->end)
179		    && (last_address >= port_info->start)) {
180
181			/* Port illegality may depend on the _OSI calls made by the BIOS */
182
183			if (acpi_gbl_osi_data >= port_info->osi_dependency) {
184				ACPI_DEBUG_PRINT((ACPI_DB_IO,
185						  "Denied AML access to port 0x%p/%X (%s 0x%.4X-0x%.4X)",
186						  ACPI_CAST_PTR(void, address),
187						  byte_width, port_info->name,
188						  port_info->start,
189						  port_info->end));
190
191				return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
192			}
193		}
194
195		/* Finished if address range ends before the end of this port */
196
197		if (last_address <= port_info->end) {
198			break;
199		}
200	}
201
202	return_ACPI_STATUS(AE_OK);
203}
204
205/******************************************************************************
206 *
207 * FUNCTION:    acpi_hw_read_port
208 *
209 * PARAMETERS:  Address             Address of I/O port/register to read
210 *              Value               Where value is placed
211 *              Width               Number of bits
212 *
213 * RETURN:      Status and value read from port
214 *
215 * DESCRIPTION: Read data from an I/O port or register. This is a front-end
216 *              to acpi_os_read_port that performs validation on both the port
217 *              address and the length.
218 *
219 *****************************************************************************/
220
221acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
222{
223	acpi_status status;
224	u32 one_byte;
225	u32 i;
226
227	/* Truncate address to 16 bits if requested */
228
229	if (acpi_gbl_truncate_io_addresses) {
230		address &= ACPI_UINT16_MAX;
231	}
232
233	/* Validate the entire request and perform the I/O */
234
235	status = acpi_hw_validate_io_request(address, width);
236	if (ACPI_SUCCESS(status)) {
237		status = acpi_os_read_port(address, value, width);
238		return status;
239	}
240
241	if (status != AE_AML_ILLEGAL_ADDRESS) {
242		return status;
243	}
244
245	/*
246	 * There has been a protection violation within the request. Fall
247	 * back to byte granularity port I/O and ignore the failing bytes.
248	 * This provides Windows compatibility.
249	 */
250	for (i = 0, *value = 0; i < width; i += 8) {
251
252		/* Validate and read one byte */
253
254		if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
255			status = acpi_os_read_port(address, &one_byte, 8);
256			if (ACPI_FAILURE(status)) {
257				return status;
258			}
259
260			*value |= (one_byte << i);
261		}
262
263		address++;
264	}
265
266	return AE_OK;
267}
268
269/******************************************************************************
270 *
271 * FUNCTION:    acpi_hw_write_port
272 *
273 * PARAMETERS:  Address             Address of I/O port/register to write
274 *              Value               Value to write
275 *              Width               Number of bits
276 *
277 * RETURN:      Status
278 *
279 * DESCRIPTION: Write data to an I/O port or register. This is a front-end
280 *              to acpi_os_write_port that performs validation on both the port
281 *              address and the length.
282 *
283 *****************************************************************************/
284
285acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
286{
287	acpi_status status;
288	u32 i;
289
290	/* Truncate address to 16 bits if requested */
291
292	if (acpi_gbl_truncate_io_addresses) {
293		address &= ACPI_UINT16_MAX;
294	}
295
296	/* Validate the entire request and perform the I/O */
297
298	status = acpi_hw_validate_io_request(address, width);
299	if (ACPI_SUCCESS(status)) {
300		status = acpi_os_write_port(address, value, width);
301		return status;
302	}
303
304	if (status != AE_AML_ILLEGAL_ADDRESS) {
305		return status;
306	}
307
308	/*
309	 * There has been a protection violation within the request. Fall
310	 * back to byte granularity port I/O and ignore the failing bytes.
311	 * This provides Windows compatibility.
312	 */
313	for (i = 0; i < width; i += 8) {
314
315		/* Validate and write one byte */
316
317		if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
318			status =
319			    acpi_os_write_port(address, (value >> i) & 0xFF, 8);
320			if (ACPI_FAILURE(status)) {
321				return status;
322			}
323		}
324
325		address++;
326	}
327
328	return AE_OK;
329}
330