803 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			803 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
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| /*******************************************************************************
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|  *
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|  * Module Name: hwregs - Read/write access functions for the various ACPI
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|  *                       control and status registers.
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|  *
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|  ******************************************************************************/
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| 
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| #include <acpi/acpi.h>
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| #include "accommon.h"
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| #include "acevents.h"
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| 
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| #define _COMPONENT          ACPI_HARDWARE
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| ACPI_MODULE_NAME("hwregs")
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| 
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| #if (!ACPI_REDUCED_HARDWARE)
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| /* Local Prototypes */
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| static u8
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| acpi_hw_get_access_bit_width(u64 address,
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| 			     struct acpi_generic_address *reg,
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| 			     u8 max_bit_width);
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| 
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| static acpi_status
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| acpi_hw_read_multiple(u32 *value,
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| 		      struct acpi_generic_address *register_a,
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| 		      struct acpi_generic_address *register_b);
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| 
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| static acpi_status
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| acpi_hw_write_multiple(u32 value,
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| 		       struct acpi_generic_address *register_a,
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| 		       struct acpi_generic_address *register_b);
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| 
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| #endif				/* !ACPI_REDUCED_HARDWARE */
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| 
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| /******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_get_access_bit_width
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|  *
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|  * PARAMETERS:  address             - GAS register address
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|  *              reg                 - GAS register structure
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|  *              max_bit_width       - Max bit_width supported (32 or 64)
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|  *
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|  * RETURN:      Status
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|  *
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|  * DESCRIPTION: Obtain optimal access bit width
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|  *
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|  ******************************************************************************/
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| 
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| static u8
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| acpi_hw_get_access_bit_width(u64 address,
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| 			     struct acpi_generic_address *reg, u8 max_bit_width)
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| {
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| 	u8 access_bit_width;
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| 
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| 	/*
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| 	 * GAS format "register", used by FADT:
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| 	 *  1. Detected if bit_offset is 0 and bit_width is 8/16/32/64;
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| 	 *  2. access_size field is ignored and bit_width field is used for
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| 	 *     determining the boundary of the IO accesses.
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| 	 * GAS format "region", used by APEI registers:
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| 	 *  1. Detected if bit_offset is not 0 or bit_width is not 8/16/32/64;
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| 	 *  2. access_size field is used for determining the boundary of the
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| 	 *     IO accesses;
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| 	 *  3. bit_offset/bit_width fields are used to describe the "region".
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| 	 *
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| 	 * Note: This algorithm assumes that the "Address" fields should always
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| 	 *       contain aligned values.
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| 	 */
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| 	if (!reg->bit_offset && reg->bit_width &&
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| 	    ACPI_IS_POWER_OF_TWO(reg->bit_width) &&
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| 	    ACPI_IS_ALIGNED(reg->bit_width, 8)) {
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| 		access_bit_width = reg->bit_width;
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| 	} else if (reg->access_width) {
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| 		access_bit_width = ACPI_ACCESS_BIT_WIDTH(reg->access_width);
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| 	} else {
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| 		access_bit_width =
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| 		    ACPI_ROUND_UP_POWER_OF_TWO_8(reg->bit_offset +
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| 						 reg->bit_width);
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| 		if (access_bit_width <= 8) {
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| 			access_bit_width = 8;
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| 		} else {
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| 			while (!ACPI_IS_ALIGNED(address, access_bit_width >> 3)) {
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| 				access_bit_width >>= 1;
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| 			}
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| 		}
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| 	}
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| 
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| 	/* Maximum IO port access bit width is 32 */
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| 
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| 	if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
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| 		max_bit_width = 32;
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| 	}
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| 
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| 	/*
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| 	 * Return access width according to the requested maximum access bit width,
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| 	 * as the caller should know the format of the register and may enforce
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| 	 * a 32-bit accesses.
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| 	 */
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| 	if (access_bit_width < max_bit_width) {
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| 		return (access_bit_width);
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| 	}
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| 	return (max_bit_width);
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| }
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| 
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| /******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_validate_register
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|  *
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|  * PARAMETERS:  reg                 - GAS register structure
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|  *              max_bit_width       - Max bit_width supported (32 or 64)
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|  *              address             - Pointer to where the gas->address
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|  *                                    is returned
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|  *
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|  * RETURN:      Status
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|  *
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|  * DESCRIPTION: Validate the contents of a GAS register. Checks the GAS
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|  *              pointer, Address, space_id, bit_width, and bit_offset.
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|  *
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|  ******************************************************************************/
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| 
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| acpi_status
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| acpi_hw_validate_register(struct acpi_generic_address *reg,
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| 			  u8 max_bit_width, u64 *address)
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| {
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| 	u8 bit_width;
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| 	u8 access_width;
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| 
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| 	/* Must have a valid pointer to a GAS structure */
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| 
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| 	if (!reg) {
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| 		return (AE_BAD_PARAMETER);
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| 	}
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| 
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| 	/*
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| 	 * Copy the target address. This handles possible alignment issues.
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| 	 * Address must not be null. A null address also indicates an optional
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| 	 * ACPI register that is not supported, so no error message.
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| 	 */
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| 	ACPI_MOVE_64_TO_64(address, ®->address);
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| 	if (!(*address)) {
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| 		return (AE_BAD_ADDRESS);
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| 	}
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| 
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| 	/* Validate the space_ID */
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| 
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| 	if ((reg->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) &&
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| 	    (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) {
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| 		ACPI_ERROR((AE_INFO,
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| 			    "Unsupported address space: 0x%X", reg->space_id));
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| 		return (AE_SUPPORT);
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| 	}
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| 
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| 	/* Validate the access_width */
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| 
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| 	if (reg->access_width > 4) {
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| 		ACPI_ERROR((AE_INFO,
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| 			    "Unsupported register access width: 0x%X",
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| 			    reg->access_width));
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| 		return (AE_SUPPORT);
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| 	}
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| 
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| 	/* Validate the bit_width, convert access_width into number of bits */
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| 
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| 	access_width =
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| 	    acpi_hw_get_access_bit_width(*address, reg, max_bit_width);
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| 	bit_width =
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| 	    ACPI_ROUND_UP(reg->bit_offset + reg->bit_width, access_width);
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| 	if (max_bit_width < bit_width) {
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| 		ACPI_WARNING((AE_INFO,
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| 			      "Requested bit width 0x%X is smaller than register bit width 0x%X",
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| 			      max_bit_width, bit_width));
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| 		return (AE_SUPPORT);
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| 	}
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| 
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| 	return (AE_OK);
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| }
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| 
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| /******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_read
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|  *
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|  * PARAMETERS:  value               - Where the value is returned
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|  *              reg                 - GAS register structure
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|  *
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|  * RETURN:      Status
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|  *
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|  * DESCRIPTION: Read from either memory or IO space. This is a 64-bit max
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|  *              version of acpi_read.
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|  *
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|  * LIMITATIONS: <These limitations also apply to acpi_hw_write>
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|  *      space_ID must be system_memory or system_IO.
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|  *
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|  ******************************************************************************/
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| 
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| acpi_status acpi_hw_read(u64 *value, struct acpi_generic_address *reg)
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| {
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| 	u64 address;
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| 	u8 access_width;
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| 	u32 bit_width;
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| 	u8 bit_offset;
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| 	u64 value64;
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| 	u32 value32;
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| 	u8 index;
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| 	acpi_status status;
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| 
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| 	ACPI_FUNCTION_NAME(hw_read);
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| 
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| 	/* Validate contents of the GAS register */
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| 
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| 	status = acpi_hw_validate_register(reg, 64, &address);
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| 	if (ACPI_FAILURE(status)) {
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| 		return (status);
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| 	}
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| 
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| 	/*
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| 	 * Initialize entire 64-bit return value to zero, convert access_width
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| 	 * into number of bits based
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| 	 */
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| 	*value = 0;
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| 	access_width = acpi_hw_get_access_bit_width(address, reg, 64);
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| 	bit_width = reg->bit_offset + reg->bit_width;
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| 	bit_offset = reg->bit_offset;
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| 
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| 	/*
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| 	 * Two address spaces supported: Memory or IO. PCI_Config is
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| 	 * not supported here because the GAS structure is insufficient
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| 	 */
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| 	index = 0;
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| 	while (bit_width) {
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| 		if (bit_offset >= access_width) {
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| 			value64 = 0;
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| 			bit_offset -= access_width;
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| 		} else {
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| 			if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
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| 				status =
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| 				    acpi_os_read_memory((acpi_physical_address)
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| 							address +
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| 							index *
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| 							ACPI_DIV_8
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| 							(access_width),
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| 							&value64, access_width);
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| 			} else {	/* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
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| 
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| 				status = acpi_hw_read_port((acpi_io_address)
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| 							   address +
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| 							   index *
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| 							   ACPI_DIV_8
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| 							   (access_width),
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| 							   &value32,
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| 							   access_width);
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| 				value64 = (u64)value32;
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| 			}
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| 		}
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| 
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| 		/*
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| 		 * Use offset style bit writes because "Index * AccessWidth" is
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| 		 * ensured to be less than 64-bits by acpi_hw_validate_register().
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| 		 */
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| 		ACPI_SET_BITS(value, index * access_width,
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| 			      ACPI_MASK_BITS_ABOVE_64(access_width), value64);
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| 
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| 		bit_width -=
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| 		    bit_width > access_width ? access_width : bit_width;
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| 		index++;
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| 	}
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| 
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| 	ACPI_DEBUG_PRINT((ACPI_DB_IO,
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| 			  "Read:  %8.8X%8.8X width %2d from %8.8X%8.8X (%s)\n",
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| 			  ACPI_FORMAT_UINT64(*value), access_width,
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| 			  ACPI_FORMAT_UINT64(address),
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| 			  acpi_ut_get_region_name(reg->space_id)));
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| 
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| 	return (status);
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| }
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| 
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| /******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_write
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|  *
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|  * PARAMETERS:  value               - Value to be written
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|  *              reg                 - GAS register structure
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|  *
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|  * RETURN:      Status
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|  *
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|  * DESCRIPTION: Write to either memory or IO space. This is a 64-bit max
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|  *              version of acpi_write.
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|  *
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|  ******************************************************************************/
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| 
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| acpi_status acpi_hw_write(u64 value, struct acpi_generic_address *reg)
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| {
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| 	u64 address;
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| 	u8 access_width;
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| 	u32 bit_width;
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| 	u8 bit_offset;
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| 	u64 value64;
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| 	u8 index;
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| 	acpi_status status;
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| 
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| 	ACPI_FUNCTION_NAME(hw_write);
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| 
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| 	/* Validate contents of the GAS register */
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| 
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| 	status = acpi_hw_validate_register(reg, 64, &address);
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| 	if (ACPI_FAILURE(status)) {
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| 		return (status);
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| 	}
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| 
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| 	/* Convert access_width into number of bits based */
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| 
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| 	access_width = acpi_hw_get_access_bit_width(address, reg, 64);
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| 	bit_width = reg->bit_offset + reg->bit_width;
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| 	bit_offset = reg->bit_offset;
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| 
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| 	/*
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| 	 * Two address spaces supported: Memory or IO. PCI_Config is
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| 	 * not supported here because the GAS structure is insufficient
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| 	 */
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| 	index = 0;
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| 	while (bit_width) {
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| 		/*
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| 		 * Use offset style bit reads because "Index * AccessWidth" is
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| 		 * ensured to be less than 64-bits by acpi_hw_validate_register().
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| 		 */
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| 		value64 = ACPI_GET_BITS(&value, index * access_width,
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| 					ACPI_MASK_BITS_ABOVE_64(access_width));
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| 
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| 		if (bit_offset >= access_width) {
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| 			bit_offset -= access_width;
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| 		} else {
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| 			if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
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| 				status =
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| 				    acpi_os_write_memory((acpi_physical_address)
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| 							 address +
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| 							 index *
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| 							 ACPI_DIV_8
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| 							 (access_width),
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| 							 value64, access_width);
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| 			} else {	/* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
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| 
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| 				status = acpi_hw_write_port((acpi_io_address)
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| 							    address +
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| 							    index *
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| 							    ACPI_DIV_8
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| 							    (access_width),
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| 							    (u32)value64,
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| 							    access_width);
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| 			}
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| 		}
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| 
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| 		/*
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| 		 * Index * access_width is ensured to be less than 32-bits by
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| 		 * acpi_hw_validate_register().
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| 		 */
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| 		bit_width -=
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| 		    bit_width > access_width ? access_width : bit_width;
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| 		index++;
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| 	}
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| 
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| 	ACPI_DEBUG_PRINT((ACPI_DB_IO,
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| 			  "Wrote: %8.8X%8.8X width %2d   to %8.8X%8.8X (%s)\n",
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| 			  ACPI_FORMAT_UINT64(value), access_width,
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| 			  ACPI_FORMAT_UINT64(address),
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| 			  acpi_ut_get_region_name(reg->space_id)));
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| 
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| 	return (status);
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| }
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| 
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| #if (!ACPI_REDUCED_HARDWARE)
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| /*******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_clear_acpi_status
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|  *
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|  * PARAMETERS:  None
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|  *
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|  * RETURN:      Status
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|  *
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|  * DESCRIPTION: Clears all fixed and general purpose status bits
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|  *
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|  ******************************************************************************/
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| 
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| acpi_status acpi_hw_clear_acpi_status(void)
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| {
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| 	acpi_status status;
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| 	acpi_cpu_flags lock_flags = 0;
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| 
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| 	ACPI_FUNCTION_TRACE(hw_clear_acpi_status);
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| 
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| 	ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %8.8X%8.8X\n",
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| 			  ACPI_BITMASK_ALL_FIXED_STATUS,
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| 			  ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address)));
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| 
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| 	lock_flags = acpi_os_acquire_raw_lock(acpi_gbl_hardware_lock);
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| 
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| 	/* Clear the fixed events in PM1 A/B */
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| 
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| 	status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
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| 					ACPI_BITMASK_ALL_FIXED_STATUS);
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| 
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| 	acpi_os_release_raw_lock(acpi_gbl_hardware_lock, lock_flags);
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| 
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| 	if (ACPI_FAILURE(status)) {
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| 		goto exit;
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| 	}
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| 
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| 	/* Clear the GPE Bits in all GPE registers in all GPE blocks */
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| 
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| 	status = acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block, NULL);
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| 
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| exit:
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| 	return_ACPI_STATUS(status);
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| }
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| 
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| /*******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_get_bit_register_info
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|  *
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|  * PARAMETERS:  register_id         - Index of ACPI Register to access
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|  *
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|  * RETURN:      The bitmask to be used when accessing the register
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|  *
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|  * DESCRIPTION: Map register_id into a register bitmask.
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|  *
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|  ******************************************************************************/
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| 
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| struct acpi_bit_register_info *acpi_hw_get_bit_register_info(u32 register_id)
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| {
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| 	ACPI_FUNCTION_ENTRY();
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| 
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| 	if (register_id > ACPI_BITREG_MAX) {
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| 		ACPI_ERROR((AE_INFO, "Invalid BitRegister ID: 0x%X",
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| 			    register_id));
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| 		return (NULL);
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| 	}
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| 
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| 	return (&acpi_gbl_bit_register_info[register_id]);
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| }
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| 
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| /******************************************************************************
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|  *
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|  * FUNCTION:    acpi_hw_write_pm1_control
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|  *
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|  * PARAMETERS:  pm1a_control        - Value to be written to PM1A control
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|  *              pm1b_control        - Value to be written to PM1B control
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|  *
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|  * RETURN:      Status
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|  *
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|  * DESCRIPTION: Write the PM1 A/B control registers. These registers are
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|  *              different than than the PM1 A/B status and enable registers
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|  *              in that different values can be written to the A/B registers.
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|  *              Most notably, the SLP_TYP bits can be different, as per the
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|  *              values returned from the _Sx predefined methods.
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|  *
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|  ******************************************************************************/
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| 
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| acpi_status acpi_hw_write_pm1_control(u32 pm1a_control, u32 pm1b_control)
 | |
| {
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| 	acpi_status status;
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| 
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| 	ACPI_FUNCTION_TRACE(hw_write_pm1_control);
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| 
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| 	status =
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| 	    acpi_hw_write(pm1a_control, &acpi_gbl_FADT.xpm1a_control_block);
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| 	if (ACPI_FAILURE(status)) {
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| 		return_ACPI_STATUS(status);
 | |
| 	}
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| 
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| 	if (acpi_gbl_FADT.xpm1b_control_block.address) {
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| 		status =
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| 		    acpi_hw_write(pm1b_control,
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| 				  &acpi_gbl_FADT.xpm1b_control_block);
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| 	}
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| 	return_ACPI_STATUS(status);
 | |
| }
 | |
| 
 | |
| /******************************************************************************
 | |
|  *
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|  * FUNCTION:    acpi_hw_register_read
 | |
|  *
 | |
|  * PARAMETERS:  register_id         - ACPI Register ID
 | |
|  *              return_value        - Where the register value is returned
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|  *
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|  * RETURN:      Status and the value read.
 | |
|  *
 | |
|  * DESCRIPTION: Read from the specified ACPI register
 | |
|  *
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|  ******************************************************************************/
 | |
| acpi_status acpi_hw_register_read(u32 register_id, u32 *return_value)
 | |
| {
 | |
| 	u32 value = 0;
 | |
| 	u64 value64;
 | |
| 	acpi_status status;
 | |
| 
 | |
| 	ACPI_FUNCTION_TRACE(hw_register_read);
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| 
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| 	switch (register_id) {
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| 	case ACPI_REGISTER_PM1_STATUS:	/* PM1 A/B: 16-bit access each */
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| 
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| 		status = acpi_hw_read_multiple(&value,
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| 					       &acpi_gbl_xpm1a_status,
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| 					       &acpi_gbl_xpm1b_status);
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| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM1_ENABLE:	/* PM1 A/B: 16-bit access each */
 | |
| 
 | |
| 		status = acpi_hw_read_multiple(&value,
 | |
| 					       &acpi_gbl_xpm1a_enable,
 | |
| 					       &acpi_gbl_xpm1b_enable);
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM1_CONTROL:	/* PM1 A/B: 16-bit access each */
 | |
| 
 | |
| 		status = acpi_hw_read_multiple(&value,
 | |
| 					       &acpi_gbl_FADT.
 | |
| 					       xpm1a_control_block,
 | |
| 					       &acpi_gbl_FADT.
 | |
| 					       xpm1b_control_block);
 | |
| 
 | |
| 		/*
 | |
| 		 * Zero the write-only bits. From the ACPI specification, "Hardware
 | |
| 		 * Write-Only Bits": "Upon reads to registers with write-only bits,
 | |
| 		 * software masks out all write-only bits."
 | |
| 		 */
 | |
| 		value &= ~ACPI_PM1_CONTROL_WRITEONLY_BITS;
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM2_CONTROL:	/* 8-bit access */
 | |
| 
 | |
| 		status =
 | |
| 		    acpi_hw_read(&value64, &acpi_gbl_FADT.xpm2_control_block);
 | |
| 		if (ACPI_SUCCESS(status)) {
 | |
| 			value = (u32)value64;
 | |
| 		}
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM_TIMER:	/* 32-bit access */
 | |
| 
 | |
| 		status = acpi_hw_read(&value64, &acpi_gbl_FADT.xpm_timer_block);
 | |
| 		if (ACPI_SUCCESS(status)) {
 | |
| 			value = (u32)value64;
 | |
| 		}
 | |
| 
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_SMI_COMMAND_BLOCK:	/* 8-bit access */
 | |
| 
 | |
| 		status =
 | |
| 		    acpi_hw_read_port(acpi_gbl_FADT.smi_command, &value, 8);
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 
 | |
| 		ACPI_ERROR((AE_INFO, "Unknown Register ID: 0x%X", register_id));
 | |
| 		status = AE_BAD_PARAMETER;
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| 	if (ACPI_SUCCESS(status)) {
 | |
| 		*return_value = (u32)value;
 | |
| 	}
 | |
| 
 | |
| 	return_ACPI_STATUS(status);
 | |
| }
 | |
| 
 | |
| /******************************************************************************
 | |
|  *
 | |
|  * FUNCTION:    acpi_hw_register_write
 | |
|  *
 | |
|  * PARAMETERS:  register_id         - ACPI Register ID
 | |
|  *              value               - The value to write
 | |
|  *
 | |
|  * RETURN:      Status
 | |
|  *
 | |
|  * DESCRIPTION: Write to the specified ACPI register
 | |
|  *
 | |
|  * NOTE: In accordance with the ACPI specification, this function automatically
 | |
|  * preserves the value of the following bits, meaning that these bits cannot be
 | |
|  * changed via this interface:
 | |
|  *
 | |
|  * PM1_CONTROL[0] = SCI_EN
 | |
|  * PM1_CONTROL[9]
 | |
|  * PM1_STATUS[11]
 | |
|  *
 | |
|  * ACPI References:
 | |
|  * 1) Hardware Ignored Bits: When software writes to a register with ignored
 | |
|  *      bit fields, it preserves the ignored bit fields
 | |
|  * 2) SCI_EN: OSPM always preserves this bit position
 | |
|  *
 | |
|  ******************************************************************************/
 | |
| 
 | |
| acpi_status acpi_hw_register_write(u32 register_id, u32 value)
 | |
| {
 | |
| 	acpi_status status;
 | |
| 	u32 read_value;
 | |
| 	u64 read_value64;
 | |
| 
 | |
| 	ACPI_FUNCTION_TRACE(hw_register_write);
 | |
| 
 | |
| 	switch (register_id) {
 | |
| 	case ACPI_REGISTER_PM1_STATUS:	/* PM1 A/B: 16-bit access each */
 | |
| 		/*
 | |
| 		 * Handle the "ignored" bit in PM1 Status. According to the ACPI
 | |
| 		 * specification, ignored bits are to be preserved when writing.
 | |
| 		 * Normally, this would mean a read/modify/write sequence. However,
 | |
| 		 * preserving a bit in the status register is different. Writing a
 | |
| 		 * one clears the status, and writing a zero preserves the status.
 | |
| 		 * Therefore, we must always write zero to the ignored bit.
 | |
| 		 *
 | |
| 		 * This behavior is clarified in the ACPI 4.0 specification.
 | |
| 		 */
 | |
| 		value &= ~ACPI_PM1_STATUS_PRESERVED_BITS;
 | |
| 
 | |
| 		status = acpi_hw_write_multiple(value,
 | |
| 						&acpi_gbl_xpm1a_status,
 | |
| 						&acpi_gbl_xpm1b_status);
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM1_ENABLE:	/* PM1 A/B: 16-bit access each */
 | |
| 
 | |
| 		status = acpi_hw_write_multiple(value,
 | |
| 						&acpi_gbl_xpm1a_enable,
 | |
| 						&acpi_gbl_xpm1b_enable);
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM1_CONTROL:	/* PM1 A/B: 16-bit access each */
 | |
| 		/*
 | |
| 		 * Perform a read first to preserve certain bits (per ACPI spec)
 | |
| 		 * Note: This includes SCI_EN, we never want to change this bit
 | |
| 		 */
 | |
| 		status = acpi_hw_read_multiple(&read_value,
 | |
| 					       &acpi_gbl_FADT.
 | |
| 					       xpm1a_control_block,
 | |
| 					       &acpi_gbl_FADT.
 | |
| 					       xpm1b_control_block);
 | |
| 		if (ACPI_FAILURE(status)) {
 | |
| 			goto exit;
 | |
| 		}
 | |
| 
 | |
| 		/* Insert the bits to be preserved */
 | |
| 
 | |
| 		ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS,
 | |
| 				 read_value);
 | |
| 
 | |
| 		/* Now we can write the data */
 | |
| 
 | |
| 		status = acpi_hw_write_multiple(value,
 | |
| 						&acpi_gbl_FADT.
 | |
| 						xpm1a_control_block,
 | |
| 						&acpi_gbl_FADT.
 | |
| 						xpm1b_control_block);
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM2_CONTROL:	/* 8-bit access */
 | |
| 		/*
 | |
| 		 * For control registers, all reserved bits must be preserved,
 | |
| 		 * as per the ACPI spec.
 | |
| 		 */
 | |
| 		status =
 | |
| 		    acpi_hw_read(&read_value64,
 | |
| 				 &acpi_gbl_FADT.xpm2_control_block);
 | |
| 		if (ACPI_FAILURE(status)) {
 | |
| 			goto exit;
 | |
| 		}
 | |
| 		read_value = (u32)read_value64;
 | |
| 
 | |
| 		/* Insert the bits to be preserved */
 | |
| 
 | |
| 		ACPI_INSERT_BITS(value, ACPI_PM2_CONTROL_PRESERVED_BITS,
 | |
| 				 read_value);
 | |
| 
 | |
| 		status =
 | |
| 		    acpi_hw_write(value, &acpi_gbl_FADT.xpm2_control_block);
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_PM_TIMER:	/* 32-bit access */
 | |
| 
 | |
| 		status = acpi_hw_write(value, &acpi_gbl_FADT.xpm_timer_block);
 | |
| 		break;
 | |
| 
 | |
| 	case ACPI_REGISTER_SMI_COMMAND_BLOCK:	/* 8-bit access */
 | |
| 
 | |
| 		/* SMI_CMD is currently always in IO space */
 | |
| 
 | |
| 		status =
 | |
| 		    acpi_hw_write_port(acpi_gbl_FADT.smi_command, value, 8);
 | |
| 		break;
 | |
| 
 | |
| 	default:
 | |
| 
 | |
| 		ACPI_ERROR((AE_INFO, "Unknown Register ID: 0x%X", register_id));
 | |
| 		status = AE_BAD_PARAMETER;
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| exit:
 | |
| 	return_ACPI_STATUS(status);
 | |
| }
 | |
| 
 | |
| /******************************************************************************
 | |
|  *
 | |
|  * FUNCTION:    acpi_hw_read_multiple
 | |
|  *
 | |
|  * PARAMETERS:  value               - Where the register value is returned
 | |
|  *              register_a           - First ACPI register (required)
 | |
|  *              register_b           - Second ACPI register (optional)
 | |
|  *
 | |
|  * RETURN:      Status
 | |
|  *
 | |
|  * DESCRIPTION: Read from the specified two-part ACPI register (such as PM1 A/B)
 | |
|  *
 | |
|  ******************************************************************************/
 | |
| 
 | |
| static acpi_status
 | |
| acpi_hw_read_multiple(u32 *value,
 | |
| 		      struct acpi_generic_address *register_a,
 | |
| 		      struct acpi_generic_address *register_b)
 | |
| {
 | |
| 	u32 value_a = 0;
 | |
| 	u32 value_b = 0;
 | |
| 	u64 value64;
 | |
| 	acpi_status status;
 | |
| 
 | |
| 	/* The first register is always required */
 | |
| 
 | |
| 	status = acpi_hw_read(&value64, register_a);
 | |
| 	if (ACPI_FAILURE(status)) {
 | |
| 		return (status);
 | |
| 	}
 | |
| 	value_a = (u32)value64;
 | |
| 
 | |
| 	/* Second register is optional */
 | |
| 
 | |
| 	if (register_b->address) {
 | |
| 		status = acpi_hw_read(&value64, register_b);
 | |
| 		if (ACPI_FAILURE(status)) {
 | |
| 			return (status);
 | |
| 		}
 | |
| 		value_b = (u32)value64;
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * OR the two return values together. No shifting or masking is necessary,
 | |
| 	 * because of how the PM1 registers are defined in the ACPI specification:
 | |
| 	 *
 | |
| 	 * "Although the bits can be split between the two register blocks (each
 | |
| 	 * register block has a unique pointer within the FADT), the bit positions
 | |
| 	 * are maintained. The register block with unimplemented bits (that is,
 | |
| 	 * those implemented in the other register block) always returns zeros,
 | |
| 	 * and writes have no side effects"
 | |
| 	 */
 | |
| 	*value = (value_a | value_b);
 | |
| 	return (AE_OK);
 | |
| }
 | |
| 
 | |
| /******************************************************************************
 | |
|  *
 | |
|  * FUNCTION:    acpi_hw_write_multiple
 | |
|  *
 | |
|  * PARAMETERS:  value               - The value to write
 | |
|  *              register_a           - First ACPI register (required)
 | |
|  *              register_b           - Second ACPI register (optional)
 | |
|  *
 | |
|  * RETURN:      Status
 | |
|  *
 | |
|  * DESCRIPTION: Write to the specified two-part ACPI register (such as PM1 A/B)
 | |
|  *
 | |
|  ******************************************************************************/
 | |
| 
 | |
| static acpi_status
 | |
| acpi_hw_write_multiple(u32 value,
 | |
| 		       struct acpi_generic_address *register_a,
 | |
| 		       struct acpi_generic_address *register_b)
 | |
| {
 | |
| 	acpi_status status;
 | |
| 
 | |
| 	/* The first register is always required */
 | |
| 
 | |
| 	status = acpi_hw_write(value, register_a);
 | |
| 	if (ACPI_FAILURE(status)) {
 | |
| 		return (status);
 | |
| 	}
 | |
| 
 | |
| 	/*
 | |
| 	 * Second register is optional
 | |
| 	 *
 | |
| 	 * No bit shifting or clearing is necessary, because of how the PM1
 | |
| 	 * registers are defined in the ACPI specification:
 | |
| 	 *
 | |
| 	 * "Although the bits can be split between the two register blocks (each
 | |
| 	 * register block has a unique pointer within the FADT), the bit positions
 | |
| 	 * are maintained. The register block with unimplemented bits (that is,
 | |
| 	 * those implemented in the other register block) always returns zeros,
 | |
| 	 * and writes have no side effects"
 | |
| 	 */
 | |
| 	if (register_b->address) {
 | |
| 		status = acpi_hw_write(value, register_b);
 | |
| 	}
 | |
| 
 | |
| 	return (status);
 | |
| }
 | |
| 
 | |
| #endif				/* !ACPI_REDUCED_HARDWARE */
 | 
