1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
4 * Module Name: hwxface - Public ACPICA hardware interfaces
6 * Copyright (C) 2000 - 2020, Intel Corp.
8 *****************************************************************************/
10 #define EXPORT_ACPI_INTERFACES
12 #include <acpi/acpi.h>
16 #define _COMPONENT ACPI_HARDWARE
17 ACPI_MODULE_NAME("hwxface")
19 /******************************************************************************
21 * FUNCTION: acpi_reset
27 * DESCRIPTION: Set reset register in memory or IO space. Note: Does not
28 * support reset register in PCI config space, this must be
31 ******************************************************************************/
32 acpi_status
acpi_reset(void)
34 struct acpi_generic_address
*reset_reg
;
37 ACPI_FUNCTION_TRACE(acpi_reset
);
39 reset_reg
= &acpi_gbl_FADT
.reset_register
;
41 /* Check if the reset register is supported */
43 if (!(acpi_gbl_FADT
.flags
& ACPI_FADT_RESET_REGISTER
) ||
44 !reset_reg
->address
) {
45 return_ACPI_STATUS(AE_NOT_EXIST
);
48 if (reset_reg
->space_id
== ACPI_ADR_SPACE_SYSTEM_IO
) {
50 * For I/O space, write directly to the OSL. This bypasses the port
51 * validation mechanism, which may block a valid write to the reset
55 * The ACPI spec requires the reset register width to be 8, so we
56 * hardcode it here and ignore the FADT value. This maintains
57 * compatibility with other ACPI implementations that have allowed
58 * BIOS code with bad register width values to go unnoticed.
60 status
= acpi_os_write_port((acpi_io_address
)reset_reg
->address
,
61 acpi_gbl_FADT
.reset_value
,
62 ACPI_RESET_REGISTER_WIDTH
);
64 /* Write the reset value to the reset register */
66 status
= acpi_hw_write(acpi_gbl_FADT
.reset_value
, reset_reg
);
69 return_ACPI_STATUS(status
);
72 ACPI_EXPORT_SYMBOL(acpi_reset
)
74 /******************************************************************************
78 * PARAMETERS: value - Where the value is returned
79 * reg - GAS register structure
83 * DESCRIPTION: Read from either memory or IO space.
85 * LIMITATIONS: <These limitations also apply to acpi_write>
86 * bit_width must be exactly 8, 16, 32, or 64.
87 * space_ID must be system_memory or system_IO.
88 * bit_offset and access_width are currently ignored, as there has
89 * not been a need to implement these.
91 ******************************************************************************/
92 acpi_status
acpi_read(u64
*return_value
, struct acpi_generic_address
*reg
)
96 ACPI_FUNCTION_NAME(acpi_read
);
98 status
= acpi_hw_read(return_value
, reg
);
102 ACPI_EXPORT_SYMBOL(acpi_read
)
104 /******************************************************************************
106 * FUNCTION: acpi_write
108 * PARAMETERS: value - Value to be written
109 * reg - GAS register structure
113 * DESCRIPTION: Write to either memory or IO space.
115 ******************************************************************************/
116 acpi_status
acpi_write(u64 value
, struct acpi_generic_address
*reg
)
120 ACPI_FUNCTION_NAME(acpi_write
);
122 status
= acpi_hw_write(value
, reg
);
126 ACPI_EXPORT_SYMBOL(acpi_write
)
128 #if (!ACPI_REDUCED_HARDWARE)
129 /*******************************************************************************
131 * FUNCTION: acpi_read_bit_register
133 * PARAMETERS: register_id - ID of ACPI Bit Register to access
134 * return_value - Value that was read from the register,
135 * normalized to bit position zero.
137 * RETURN: Status and the value read from the specified Register. Value
138 * returned is normalized to bit0 (is shifted all the way right)
140 * DESCRIPTION: ACPI bit_register read function. Does not acquire the HW lock.
142 * SUPPORTS: Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
145 * Note: The hardware lock is not required when reading the ACPI bit registers
146 * since almost all of them are single bit and it does not matter that
147 * the parent hardware register can be split across two physical
148 * registers. The only multi-bit field is SLP_TYP in the PM1 control
149 * register, but this field does not cross an 8-bit boundary (nor does
150 * it make much sense to actually read this field.)
152 ******************************************************************************/
153 acpi_status
acpi_read_bit_register(u32 register_id
, u32
*return_value
)
155 struct acpi_bit_register_info
*bit_reg_info
;
160 ACPI_FUNCTION_TRACE_U32(acpi_read_bit_register
, register_id
);
162 /* Get the info structure corresponding to the requested ACPI Register */
164 bit_reg_info
= acpi_hw_get_bit_register_info(register_id
);
166 return_ACPI_STATUS(AE_BAD_PARAMETER
);
169 /* Read the entire parent register */
171 status
= acpi_hw_register_read(bit_reg_info
->parent_register
,
173 if (ACPI_FAILURE(status
)) {
174 return_ACPI_STATUS(status
);
177 /* Normalize the value that was read, mask off other bits */
179 value
= ((register_value
& bit_reg_info
->access_bit_mask
)
180 >> bit_reg_info
->bit_position
);
182 ACPI_DEBUG_PRINT((ACPI_DB_IO
,
183 "BitReg %X, ParentReg %X, Actual %8.8X, ReturnValue %8.8X\n",
184 register_id
, bit_reg_info
->parent_register
,
185 register_value
, value
));
187 *return_value
= value
;
188 return_ACPI_STATUS(AE_OK
);
191 ACPI_EXPORT_SYMBOL(acpi_read_bit_register
)
193 /*******************************************************************************
195 * FUNCTION: acpi_write_bit_register
197 * PARAMETERS: register_id - ID of ACPI Bit Register to access
198 * value - Value to write to the register, in bit
199 * position zero. The bit is automatically
200 * shifted to the correct position.
204 * DESCRIPTION: ACPI Bit Register write function. Acquires the hardware lock
205 * since most operations require a read/modify/write sequence.
207 * SUPPORTS: Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
210 * Note that at this level, the fact that there may be actually two
211 * hardware registers (A and B - and B may not exist) is abstracted.
213 ******************************************************************************/
214 acpi_status
acpi_write_bit_register(u32 register_id
, u32 value
)
216 struct acpi_bit_register_info
*bit_reg_info
;
217 acpi_cpu_flags lock_flags
;
219 acpi_status status
= AE_OK
;
221 ACPI_FUNCTION_TRACE_U32(acpi_write_bit_register
, register_id
);
223 /* Get the info structure corresponding to the requested ACPI Register */
225 bit_reg_info
= acpi_hw_get_bit_register_info(register_id
);
227 return_ACPI_STATUS(AE_BAD_PARAMETER
);
230 lock_flags
= acpi_os_acquire_raw_lock(acpi_gbl_hardware_lock
);
233 * At this point, we know that the parent register is one of the
234 * following: PM1 Status, PM1 Enable, PM1 Control, or PM2 Control
236 if (bit_reg_info
->parent_register
!= ACPI_REGISTER_PM1_STATUS
) {
238 * 1) Case for PM1 Enable, PM1 Control, and PM2 Control
240 * Perform a register read to preserve the bits that we are not
243 status
= acpi_hw_register_read(bit_reg_info
->parent_register
,
245 if (ACPI_FAILURE(status
)) {
246 goto unlock_and_exit
;
250 * Insert the input bit into the value that was just read
251 * and write the register
253 ACPI_REGISTER_INSERT_VALUE(register_value
,
254 bit_reg_info
->bit_position
,
255 bit_reg_info
->access_bit_mask
,
258 status
= acpi_hw_register_write(bit_reg_info
->parent_register
,
262 * 2) Case for PM1 Status
264 * The Status register is different from the rest. Clear an event
265 * by writing 1, writing 0 has no effect. So, the only relevant
266 * information is the single bit we're interested in, all others
267 * should be written as 0 so they will be left unchanged.
269 register_value
= ACPI_REGISTER_PREPARE_BITS(value
,
275 /* No need to write the register if value is all zeros */
277 if (register_value
) {
279 acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS
,
284 ACPI_DEBUG_PRINT((ACPI_DB_IO
,
285 "BitReg %X, ParentReg %X, Value %8.8X, Actual %8.8X\n",
286 register_id
, bit_reg_info
->parent_register
, value
,
291 acpi_os_release_raw_lock(acpi_gbl_hardware_lock
, lock_flags
);
292 return_ACPI_STATUS(status
);
295 ACPI_EXPORT_SYMBOL(acpi_write_bit_register
)
296 #endif /* !ACPI_REDUCED_HARDWARE */
297 /*******************************************************************************
299 * FUNCTION: acpi_get_sleep_type_data
301 * PARAMETERS: sleep_state - Numeric sleep state
302 * *sleep_type_a - Where SLP_TYPa is returned
303 * *sleep_type_b - Where SLP_TYPb is returned
307 * DESCRIPTION: Obtain the SLP_TYPa and SLP_TYPb values for the requested
308 * sleep state via the appropriate \_Sx object.
310 * The sleep state package returned from the corresponding \_Sx_ object
311 * must contain at least one integer.
314 * Added support for a package that contains two integers. This
315 * goes against the ACPI specification which defines this object as a
316 * package with one encoded DWORD integer. However, existing practice
317 * by many BIOS vendors is to return a package with 2 or more integer
318 * elements, at least one per sleep type (A/B).
321 * Therefore, we must be prepared to accept a package with either a
322 * single integer or multiple integers.
324 * The single integer DWORD format is as follows:
325 * BYTE 0 - Value for the PM1A SLP_TYP register
326 * BYTE 1 - Value for the PM1B SLP_TYP register
327 * BYTE 2-3 - Reserved
329 * The dual integer format is as follows:
330 * Integer 0 - Value for the PM1A SLP_TYP register
331 * Integer 1 - Value for the PM1A SLP_TYP register
333 ******************************************************************************/
335 acpi_get_sleep_type_data(u8 sleep_state
, u8
*sleep_type_a
, u8
*sleep_type_b
)
338 struct acpi_evaluate_info
*info
;
339 union acpi_operand_object
**elements
;
341 ACPI_FUNCTION_TRACE(acpi_get_sleep_type_data
);
343 /* Validate parameters */
345 if ((sleep_state
> ACPI_S_STATES_MAX
) || !sleep_type_a
|| !sleep_type_b
) {
346 return_ACPI_STATUS(AE_BAD_PARAMETER
);
349 /* Allocate the evaluation information block */
351 info
= ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info
));
353 return_ACPI_STATUS(AE_NO_MEMORY
);
357 * Evaluate the \_Sx namespace object containing the register values
360 info
->relative_pathname
= acpi_gbl_sleep_state_names
[sleep_state
];
362 status
= acpi_ns_evaluate(info
);
363 if (ACPI_FAILURE(status
)) {
364 if (status
== AE_NOT_FOUND
) {
366 /* The _Sx states are optional, ignore NOT_FOUND */
371 goto warning_cleanup
;
374 /* Must have a return object */
376 if (!info
->return_object
) {
377 ACPI_ERROR((AE_INFO
, "No Sleep State object returned from [%s]",
378 info
->relative_pathname
));
379 status
= AE_AML_NO_RETURN_VALUE
;
380 goto warning_cleanup
;
383 /* Return object must be of type Package */
385 if (info
->return_object
->common
.type
!= ACPI_TYPE_PACKAGE
) {
387 "Sleep State return object is not a Package"));
388 status
= AE_AML_OPERAND_TYPE
;
389 goto return_value_cleanup
;
393 * Any warnings about the package length or the object types have
394 * already been issued by the predefined name module -- there is no
395 * need to repeat them here.
397 elements
= info
->return_object
->package
.elements
;
398 switch (info
->return_object
->package
.count
) {
401 status
= AE_AML_PACKAGE_LIMIT
;
406 if (elements
[0]->common
.type
!= ACPI_TYPE_INTEGER
) {
407 status
= AE_AML_OPERAND_TYPE
;
411 /* A valid _Sx_ package with one integer */
413 *sleep_type_a
= (u8
)elements
[0]->integer
.value
;
414 *sleep_type_b
= (u8
)(elements
[0]->integer
.value
>> 8);
420 if ((elements
[0]->common
.type
!= ACPI_TYPE_INTEGER
) ||
421 (elements
[1]->common
.type
!= ACPI_TYPE_INTEGER
)) {
422 status
= AE_AML_OPERAND_TYPE
;
426 /* A valid _Sx_ package with two integers */
428 *sleep_type_a
= (u8
)elements
[0]->integer
.value
;
429 *sleep_type_b
= (u8
)elements
[1]->integer
.value
;
433 return_value_cleanup
:
434 acpi_ut_remove_reference(info
->return_object
);
437 if (ACPI_FAILURE(status
)) {
438 ACPI_EXCEPTION((AE_INFO
, status
,
439 "While evaluating Sleep State [%s]",
440 info
->relative_pathname
));
445 return_ACPI_STATUS(status
);
448 ACPI_EXPORT_SYMBOL(acpi_get_sleep_type_data
)