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}
326