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v3.5.6
  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}
v6.9.4
  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 - 2023, Intel Corp.
 
 
 
 
  7 *
  8 *****************************************************************************/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  9
 10#include <acpi/acpi.h>
 11#include "accommon.h"
 12
 13#define _COMPONENT          ACPI_HARDWARE
 14ACPI_MODULE_NAME("hwvalid")
 15
 16/* Local prototypes */
 17static acpi_status
 18acpi_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 nothing newer than
 27 * the specific _OSI strings.
 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 */
 51static 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
 89static acpi_status
 90acpi_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 (port_info->osi_dependency == ACPI_ALWAYS_ILLEGAL ||
149			    acpi_gbl_osi_data == port_info->osi_dependency) {
150				ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
151						  "Denied AML access to port 0x%8.8X%8.8X/%X (%s 0x%.4X-0x%.4X)\n",
152						  ACPI_FORMAT_UINT64(address),
153						  byte_width, port_info->name,
154						  port_info->start,
155						  port_info->end));
156
157				return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
158			}
159		}
160
161		/* Finished if address range ends before the end of this port */
162
163		if (last_address <= port_info->end) {
164			break;
165		}
166	}
167
168	return_ACPI_STATUS(AE_OK);
169}
170
171/******************************************************************************
172 *
173 * FUNCTION:    acpi_hw_read_port
174 *
175 * PARAMETERS:  Address             Address of I/O port/register to read
176 *              Value               Where value (data) is returned
177 *              Width               Number of bits
178 *
179 * RETURN:      Status and value read from port
180 *
181 * DESCRIPTION: Read data from an I/O port or register. This is a front-end
182 *              to acpi_os_read_port that performs validation on both the port
183 *              address and the length.
184 *
185 *****************************************************************************/
186
187acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
188{
189	acpi_status status;
190	u32 one_byte;
191	u32 i;
192
193	/* Truncate address to 16 bits if requested */
194
195	if (acpi_gbl_truncate_io_addresses) {
196		address &= ACPI_UINT16_MAX;
197	}
198
199	/* Validate the entire request and perform the I/O */
200
201	status = acpi_hw_validate_io_request(address, width);
202	if (ACPI_SUCCESS(status)) {
203		status = acpi_os_read_port(address, value, width);
204		return (status);
205	}
206
207	if (status != AE_AML_ILLEGAL_ADDRESS) {
208		return (status);
209	}
210
211	/*
212	 * There has been a protection violation within the request. Fall
213	 * back to byte granularity port I/O and ignore the failing bytes.
214	 * This provides compatibility with other ACPI implementations.
215	 */
216	for (i = 0, *value = 0; i < width; i += 8) {
217
218		/* Validate and read one byte */
219
220		if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
221			status = acpi_os_read_port(address, &one_byte, 8);
222			if (ACPI_FAILURE(status)) {
223				return (status);
224			}
225
226			*value |= (one_byte << i);
227		}
228
229		address++;
230	}
231
232	return (AE_OK);
233}
234
235/******************************************************************************
236 *
237 * FUNCTION:    acpi_hw_write_port
238 *
239 * PARAMETERS:  Address             Address of I/O port/register to write
240 *              Value               Value to write
241 *              Width               Number of bits
242 *
243 * RETURN:      Status
244 *
245 * DESCRIPTION: Write data to an I/O port or register. This is a front-end
246 *              to acpi_os_write_port that performs validation on both the port
247 *              address and the length.
248 *
249 *****************************************************************************/
250
251acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
252{
253	acpi_status status;
254	u32 i;
255
256	/* Truncate address to 16 bits if requested */
257
258	if (acpi_gbl_truncate_io_addresses) {
259		address &= ACPI_UINT16_MAX;
260	}
261
262	/* Validate the entire request and perform the I/O */
263
264	status = acpi_hw_validate_io_request(address, width);
265	if (ACPI_SUCCESS(status)) {
266		status = acpi_os_write_port(address, value, width);
267		return (status);
268	}
269
270	if (status != AE_AML_ILLEGAL_ADDRESS) {
271		return (status);
272	}
273
274	/*
275	 * There has been a protection violation within the request. Fall
276	 * back to byte granularity port I/O and ignore the failing bytes.
277	 * This provides compatibility with other ACPI implementations.
278	 */
279	for (i = 0; i < width; i += 8) {
280
281		/* Validate and write one byte */
282
283		if (acpi_hw_validate_io_request(address, 8) == AE_OK) {
284			status =
285			    acpi_os_write_port(address, (value >> i) & 0xFF, 8);
286			if (ACPI_FAILURE(status)) {
287				return (status);
288			}
289		}
290
291		address++;
292	}
293
294	return (AE_OK);
295}
296
297/******************************************************************************
298 *
299 * FUNCTION:    acpi_hw_validate_io_block
300 *
301 * PARAMETERS:  Address             Address of I/O port/register blobk
302 *              bit_width           Number of bits (8,16,32) in each register
303 *              count               Number of registers in the block
304 *
305 * RETURN:      Status
306 *
307 * DESCRIPTION: Validates a block of I/O ports/registers.
308 *
309 ******************************************************************************/
310
311acpi_status acpi_hw_validate_io_block(u64 address, u32 bit_width, u32 count)
312{
313	acpi_status status;
314
315	while (count--) {
316		status = acpi_hw_validate_io_request((acpi_io_address)address,
317						     bit_width);
318		if (ACPI_FAILURE(status))
319			return_ACPI_STATUS(status);
320
321		address += ACPI_DIV_8(bit_width);
322	}
323
324	return_ACPI_STATUS(AE_OK);
325}