cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

hwxface.c (13453B)


      1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
      2/******************************************************************************
      3 *
      4 * Module Name: hwxface - Public ACPICA hardware interfaces
      5 *
      6 * Copyright (C) 2000 - 2022, Intel Corp.
      7 *
      8 *****************************************************************************/
      9
     10#define EXPORT_ACPI_INTERFACES
     11
     12#include <acpi/acpi.h>
     13#include "accommon.h"
     14#include "acnamesp.h"
     15
     16#define _COMPONENT          ACPI_HARDWARE
     17ACPI_MODULE_NAME("hwxface")
     18
     19/******************************************************************************
     20 *
     21 * FUNCTION:    acpi_reset
     22 *
     23 * PARAMETERS:  None
     24 *
     25 * RETURN:      Status
     26 *
     27 * DESCRIPTION: Set reset register in memory or IO space. Note: Does not
     28 *              support reset register in PCI config space, this must be
     29 *              handled separately.
     30 *
     31 ******************************************************************************/
     32acpi_status acpi_reset(void)
     33{
     34	struct acpi_generic_address *reset_reg;
     35	acpi_status status;
     36
     37	ACPI_FUNCTION_TRACE(acpi_reset);
     38
     39	reset_reg = &acpi_gbl_FADT.reset_register;
     40
     41	/* Check if the reset register is supported */
     42
     43	if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) ||
     44	    !reset_reg->address) {
     45		return_ACPI_STATUS(AE_NOT_EXIST);
     46	}
     47
     48	if (reset_reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
     49		/*
     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
     52		 * register.
     53		 *
     54		 * NOTE:
     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.
     59		 */
     60		status = acpi_os_write_port((acpi_io_address)reset_reg->address,
     61					    acpi_gbl_FADT.reset_value,
     62					    ACPI_RESET_REGISTER_WIDTH);
     63	} else {
     64		/* Write the reset value to the reset register */
     65
     66		status = acpi_hw_write(acpi_gbl_FADT.reset_value, reset_reg);
     67	}
     68
     69	return_ACPI_STATUS(status);
     70}
     71
     72ACPI_EXPORT_SYMBOL(acpi_reset)
     73
     74/******************************************************************************
     75 *
     76 * FUNCTION:    acpi_read
     77 *
     78 * PARAMETERS:  value               - Where the value is returned
     79 *              reg                 - GAS register structure
     80 *
     81 * RETURN:      Status
     82 *
     83 * DESCRIPTION: Read from either memory or IO space.
     84 *
     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.
     90 *
     91 ******************************************************************************/
     92acpi_status acpi_read(u64 *return_value, struct acpi_generic_address *reg)
     93{
     94	acpi_status status;
     95
     96	ACPI_FUNCTION_NAME(acpi_read);
     97
     98	status = acpi_hw_read(return_value, reg);
     99	return (status);
    100}
    101
    102ACPI_EXPORT_SYMBOL(acpi_read)
    103
    104/******************************************************************************
    105 *
    106 * FUNCTION:    acpi_write
    107 *
    108 * PARAMETERS:  value               - Value to be written
    109 *              reg                 - GAS register structure
    110 *
    111 * RETURN:      Status
    112 *
    113 * DESCRIPTION: Write to either memory or IO space.
    114 *
    115 ******************************************************************************/
    116acpi_status acpi_write(u64 value, struct acpi_generic_address *reg)
    117{
    118	acpi_status status;
    119
    120	ACPI_FUNCTION_NAME(acpi_write);
    121
    122	status = acpi_hw_write(value, reg);
    123	return (status);
    124}
    125
    126ACPI_EXPORT_SYMBOL(acpi_write)
    127
    128#if (!ACPI_REDUCED_HARDWARE)
    129/*******************************************************************************
    130 *
    131 * FUNCTION:    acpi_read_bit_register
    132 *
    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.
    136 *
    137 * RETURN:      Status and the value read from the specified Register. Value
    138 *              returned is normalized to bit0 (is shifted all the way right)
    139 *
    140 * DESCRIPTION: ACPI bit_register read function. Does not acquire the HW lock.
    141 *
    142 * SUPPORTS:    Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
    143 *              PM2 Control.
    144 *
    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.)
    151 *
    152 ******************************************************************************/
    153acpi_status acpi_read_bit_register(u32 register_id, u32 *return_value)
    154{
    155	struct acpi_bit_register_info *bit_reg_info;
    156	u32 register_value;
    157	u32 value;
    158	acpi_status status;
    159
    160	ACPI_FUNCTION_TRACE_U32(acpi_read_bit_register, register_id);
    161
    162	/* Get the info structure corresponding to the requested ACPI Register */
    163
    164	bit_reg_info = acpi_hw_get_bit_register_info(register_id);
    165	if (!bit_reg_info) {
    166		return_ACPI_STATUS(AE_BAD_PARAMETER);
    167	}
    168
    169	/* Read the entire parent register */
    170
    171	status = acpi_hw_register_read(bit_reg_info->parent_register,
    172				       &register_value);
    173	if (ACPI_FAILURE(status)) {
    174		return_ACPI_STATUS(status);
    175	}
    176
    177	/* Normalize the value that was read, mask off other bits */
    178
    179	value = ((register_value & bit_reg_info->access_bit_mask)
    180		 >> bit_reg_info->bit_position);
    181
    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));
    186
    187	*return_value = value;
    188	return_ACPI_STATUS(AE_OK);
    189}
    190
    191ACPI_EXPORT_SYMBOL(acpi_read_bit_register)
    192
    193/*******************************************************************************
    194 *
    195 * FUNCTION:    acpi_write_bit_register
    196 *
    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.
    201 *
    202 * RETURN:      Status
    203 *
    204 * DESCRIPTION: ACPI Bit Register write function. Acquires the hardware lock
    205 *              since most operations require a read/modify/write sequence.
    206 *
    207 * SUPPORTS:    Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
    208 *              PM2 Control.
    209 *
    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.
    212 *
    213 ******************************************************************************/
    214acpi_status acpi_write_bit_register(u32 register_id, u32 value)
    215{
    216	struct acpi_bit_register_info *bit_reg_info;
    217	acpi_cpu_flags lock_flags;
    218	u32 register_value;
    219	acpi_status status = AE_OK;
    220
    221	ACPI_FUNCTION_TRACE_U32(acpi_write_bit_register, register_id);
    222
    223	/* Get the info structure corresponding to the requested ACPI Register */
    224
    225	bit_reg_info = acpi_hw_get_bit_register_info(register_id);
    226	if (!bit_reg_info) {
    227		return_ACPI_STATUS(AE_BAD_PARAMETER);
    228	}
    229
    230	lock_flags = acpi_os_acquire_raw_lock(acpi_gbl_hardware_lock);
    231
    232	/*
    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
    235	 */
    236	if (bit_reg_info->parent_register != ACPI_REGISTER_PM1_STATUS) {
    237		/*
    238		 * 1) Case for PM1 Enable, PM1 Control, and PM2 Control
    239		 *
    240		 * Perform a register read to preserve the bits that we are not
    241		 * interested in
    242		 */
    243		status = acpi_hw_register_read(bit_reg_info->parent_register,
    244					       &register_value);
    245		if (ACPI_FAILURE(status)) {
    246			goto unlock_and_exit;
    247		}
    248
    249		/*
    250		 * Insert the input bit into the value that was just read
    251		 * and write the register
    252		 */
    253		ACPI_REGISTER_INSERT_VALUE(register_value,
    254					   bit_reg_info->bit_position,
    255					   bit_reg_info->access_bit_mask,
    256					   value);
    257
    258		status = acpi_hw_register_write(bit_reg_info->parent_register,
    259						register_value);
    260	} else {
    261		/*
    262		 * 2) Case for PM1 Status
    263		 *
    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.
    268		 */
    269		register_value = ACPI_REGISTER_PREPARE_BITS(value,
    270							    bit_reg_info->
    271							    bit_position,
    272							    bit_reg_info->
    273							    access_bit_mask);
    274
    275		/* No need to write the register if value is all zeros */
    276
    277		if (register_value) {
    278			status =
    279			    acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
    280						   register_value);
    281		}
    282	}
    283
    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,
    287			  register_value));
    288
    289unlock_and_exit:
    290
    291	acpi_os_release_raw_lock(acpi_gbl_hardware_lock, lock_flags);
    292	return_ACPI_STATUS(status);
    293}
    294
    295ACPI_EXPORT_SYMBOL(acpi_write_bit_register)
    296#endif				/* !ACPI_REDUCED_HARDWARE */
    297/*******************************************************************************
    298 *
    299 * FUNCTION:    acpi_get_sleep_type_data
    300 *
    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
    304 *
    305 * RETURN:      Status
    306 *
    307 * DESCRIPTION: Obtain the SLP_TYPa and SLP_TYPb values for the requested
    308 *              sleep state via the appropriate \_Sx object.
    309 *
    310 *  The sleep state package returned from the corresponding \_Sx_ object
    311 *  must contain at least one integer.
    312 *
    313 *  March 2005:
    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).
    319 *
    320 *  January 2013:
    321 *  Therefore, we must be prepared to accept a package with either a
    322 *  single integer or multiple integers.
    323 *
    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
    328 *
    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
    332 *
    333 ******************************************************************************/
    334acpi_status
    335acpi_get_sleep_type_data(u8 sleep_state, u8 *sleep_type_a, u8 *sleep_type_b)
    336{
    337	acpi_status status;
    338	struct acpi_evaluate_info *info;
    339	union acpi_operand_object **elements;
    340
    341	ACPI_FUNCTION_TRACE(acpi_get_sleep_type_data);
    342
    343	/* Validate parameters */
    344
    345	if ((sleep_state > ACPI_S_STATES_MAX) || !sleep_type_a || !sleep_type_b) {
    346		return_ACPI_STATUS(AE_BAD_PARAMETER);
    347	}
    348
    349	/* Allocate the evaluation information block */
    350
    351	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
    352	if (!info) {
    353		return_ACPI_STATUS(AE_NO_MEMORY);
    354	}
    355
    356	/*
    357	 * Evaluate the \_Sx namespace object containing the register values
    358	 * for this state
    359	 */
    360	info->relative_pathname = acpi_gbl_sleep_state_names[sleep_state];
    361
    362	status = acpi_ns_evaluate(info);
    363	if (ACPI_FAILURE(status)) {
    364		if (status == AE_NOT_FOUND) {
    365
    366			/* The _Sx states are optional, ignore NOT_FOUND */
    367
    368			goto final_cleanup;
    369		}
    370
    371		goto warning_cleanup;
    372	}
    373
    374	/* Must have a return object */
    375
    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;
    381	}
    382
    383	/* Return object must be of type Package */
    384
    385	if (info->return_object->common.type != ACPI_TYPE_PACKAGE) {
    386		ACPI_ERROR((AE_INFO,
    387			    "Sleep State return object is not a Package"));
    388		status = AE_AML_OPERAND_TYPE;
    389		goto return_value_cleanup;
    390	}
    391
    392	/*
    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.
    396	 */
    397	elements = info->return_object->package.elements;
    398	switch (info->return_object->package.count) {
    399	case 0:
    400
    401		status = AE_AML_PACKAGE_LIMIT;
    402		break;
    403
    404	case 1:
    405
    406		if (elements[0]->common.type != ACPI_TYPE_INTEGER) {
    407			status = AE_AML_OPERAND_TYPE;
    408			break;
    409		}
    410
    411		/* A valid _Sx_ package with one integer */
    412
    413		*sleep_type_a = (u8)elements[0]->integer.value;
    414		*sleep_type_b = (u8)(elements[0]->integer.value >> 8);
    415		break;
    416
    417	case 2:
    418	default:
    419
    420		if ((elements[0]->common.type != ACPI_TYPE_INTEGER) ||
    421		    (elements[1]->common.type != ACPI_TYPE_INTEGER)) {
    422			status = AE_AML_OPERAND_TYPE;
    423			break;
    424		}
    425
    426		/* A valid _Sx_ package with two integers */
    427
    428		*sleep_type_a = (u8)elements[0]->integer.value;
    429		*sleep_type_b = (u8)elements[1]->integer.value;
    430		break;
    431	}
    432
    433return_value_cleanup:
    434	acpi_ut_remove_reference(info->return_object);
    435
    436warning_cleanup:
    437	if (ACPI_FAILURE(status)) {
    438		ACPI_EXCEPTION((AE_INFO, status,
    439				"While evaluating Sleep State [%s]",
    440				info->relative_pathname));
    441	}
    442
    443final_cleanup:
    444	ACPI_FREE(info);
    445	return_ACPI_STATUS(status);
    446}
    447
    448ACPI_EXPORT_SYMBOL(acpi_get_sleep_type_data)