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
48ACPI_MODULE_NAME("hwvalid")
49
50/* Local prototypes */
51static acpi_status
52acpi_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 */
85static 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
123static acpi_status
124acpi_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
220acpi_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
284acpi_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