/******************************************************************************* * * Module Name: hwregs - Read/write access functions for the various ACPI * control and status registers. * ******************************************************************************/ /****************************************************************************** * * 1. Copyright Notice * * Some or all of this work - Copyright (c) 1999 - 2023, Intel Corp. * All rights reserved. * * 2. License * * 2.1. This is your license from Intel Corp. under its intellectual property * rights. You may have additional license terms from the party that provided * you this software, covering your right to use that party's intellectual * property rights. * * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a * copy of the source code appearing in this file ("Covered Code") an * irrevocable, perpetual, worldwide license under Intel's copyrights in the * base code distributed originally by Intel ("Original Intel Code") to copy, * make derivatives, distribute, use and display any portion of the Covered * Code in any form, with the right to sublicense such rights; and * * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent * license (with the right to sublicense), under only those claims of Intel * patents that are infringed by the Original Intel Code, to make, use, sell, * offer to sell, and import the Covered Code and derivative works thereof * solely to the minimum extent necessary to exercise the above copyright * license, and in no event shall the patent license extend to any additions * to or modifications of the Original Intel Code. No other license or right * is granted directly or by implication, estoppel or otherwise; * * The above copyright and patent license is granted only if the following * conditions are met: * * 3. Conditions * * 3.1. Redistribution of Source with Rights to Further Distribute Source. * Redistribution of source code of any substantial portion of the Covered * Code or modification with rights to further distribute source must include * the above Copyright Notice, the above License, this list of Conditions, * and the following Disclaimer and Export Compliance provision. In addition, * Licensee must cause all Covered Code to which Licensee contributes to * contain a file documenting the changes Licensee made to create that Covered * Code and the date of any change. Licensee must include in that file the * documentation of any changes made by any predecessor Licensee. Licensee * must include a prominent statement that the modification is derived, * directly or indirectly, from Original Intel Code. * * 3.2. Redistribution of Source with no Rights to Further Distribute Source. * Redistribution of source code of any substantial portion of the Covered * Code or modification without rights to further distribute source must * include the following Disclaimer and Export Compliance provision in the * documentation and/or other materials provided with distribution. In * addition, Licensee may not authorize further sublicense of source of any * portion of the Covered Code, and must include terms to the effect that the * license from Licensee to its licensee is limited to the intellectual * property embodied in the software Licensee provides to its licensee, and * not to intellectual property embodied in modifications its licensee may * make. * * 3.3. Redistribution of Executable. Redistribution in executable form of any * substantial portion of the Covered Code or modification must reproduce the * above Copyright Notice, and the following Disclaimer and Export Compliance * provision in the documentation and/or other materials provided with the * distribution. * * 3.4. Intel retains all right, title, and interest in and to the Original * Intel Code. * * 3.5. Neither the name Intel nor any other trademark owned or controlled by * Intel shall be used in advertising or otherwise to promote the sale, use or * other dealings in products derived from or relating to the Covered Code * without prior written authorization from Intel. * * 4. Disclaimer and Export Compliance * * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A * PARTICULAR PURPOSE. * * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY * LIMITED REMEDY. * * 4.3. Licensee shall not export, either directly or indirectly, any of this * software or system incorporating such software without first obtaining any * required license or other approval from the U. S. Department of Commerce or * any other agency or department of the United States Government. In the * event Licensee exports any such software from the United States or * re-exports any such software from a foreign destination, Licensee shall * ensure that the distribution and export/re-export of the software is in * compliance with all laws, regulations, orders, or other restrictions of the * U.S. Export Administration Regulations. Licensee agrees that neither it nor * any of its subsidiaries will export/re-export any technical data, process, * software, or service, directly or indirectly, to any country for which the * United States government or any agency thereof requires an export license, * other governmental approval, or letter of assurance, without first obtaining * such license, approval or letter. * ***************************************************************************** * * Alternatively, you may choose to be licensed under the terms of the * following license: * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions, and the following disclaimer, * without modification. * 2. Redistributions in binary form must reproduce at minimum a disclaimer * substantially similar to the "NO WARRANTY" disclaimer below * ("Disclaimer") and any redistribution must be conditioned upon * including a substantially similar Disclaimer requirement for further * binary redistribution. * 3. Neither the names of the above-listed copyright holders nor the names * of any contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * Alternatively, you may choose to be licensed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * *****************************************************************************/ #include #include #include #define _COMPONENT ACPI_HARDWARE ACPI_MODULE_NAME ("hwregs") #if (!ACPI_REDUCED_HARDWARE) /* Local Prototypes */ static UINT8 AcpiHwGetAccessBitWidth ( UINT64 Address, ACPI_GENERIC_ADDRESS *Reg, UINT8 MaxBitWidth); static ACPI_STATUS AcpiHwReadMultiple ( UINT32 *Value, ACPI_GENERIC_ADDRESS *RegisterA, ACPI_GENERIC_ADDRESS *RegisterB); static ACPI_STATUS AcpiHwWriteMultiple ( UINT32 Value, ACPI_GENERIC_ADDRESS *RegisterA, ACPI_GENERIC_ADDRESS *RegisterB); #endif /* !ACPI_REDUCED_HARDWARE */ /****************************************************************************** * * FUNCTION: AcpiHwGetAccessBitWidth * * PARAMETERS: Address - GAS register address * Reg - GAS register structure * MaxBitWidth - Max BitWidth supported (32 or 64) * * RETURN: Status * * DESCRIPTION: Obtain optimal access bit width * ******************************************************************************/ static UINT8 AcpiHwGetAccessBitWidth ( UINT64 Address, ACPI_GENERIC_ADDRESS *Reg, UINT8 MaxBitWidth) { UINT8 AccessBitWidth; /* * GAS format "register", used by FADT: * 1. Detected if BitOffset is 0 and BitWidth is 8/16/32/64; * 2. AccessSize field is ignored and BitWidth field is used for * determining the boundary of the IO accesses. * GAS format "region", used by APEI registers: * 1. Detected if BitOffset is not 0 or BitWidth is not 8/16/32/64; * 2. AccessSize field is used for determining the boundary of the * IO accesses; * 3. BitOffset/BitWidth fields are used to describe the "region". * * Note: This algorithm assumes that the "Address" fields should always * contain aligned values. */ if (!Reg->BitOffset && Reg->BitWidth && ACPI_IS_POWER_OF_TWO (Reg->BitWidth) && ACPI_IS_ALIGNED (Reg->BitWidth, 8)) { AccessBitWidth = Reg->BitWidth; } else if (Reg->AccessWidth) { AccessBitWidth = ACPI_ACCESS_BIT_WIDTH (Reg->AccessWidth); } else { AccessBitWidth = ACPI_ROUND_UP_POWER_OF_TWO_8 ( Reg->BitOffset + Reg->BitWidth); if (AccessBitWidth <= 8) { AccessBitWidth = 8; } else { while (!ACPI_IS_ALIGNED (Address, AccessBitWidth >> 3)) { AccessBitWidth >>= 1; } } } /* Maximum IO port access bit width is 32 */ if (Reg->SpaceId == ACPI_ADR_SPACE_SYSTEM_IO) { MaxBitWidth = 32; } /* * Return access width according to the requested maximum access bit width, * as the caller should know the format of the register and may enforce * a 32-bit accesses. */ if (AccessBitWidth < MaxBitWidth) { return (AccessBitWidth); } return (MaxBitWidth); } /****************************************************************************** * * FUNCTION: AcpiHwValidateRegister * * PARAMETERS: Reg - GAS register structure * MaxBitWidth - Max BitWidth supported (32 or 64) * Address - Pointer to where the gas->address * is returned * * RETURN: Status * * DESCRIPTION: Validate the contents of a GAS register. Checks the GAS * pointer, Address, SpaceId, BitWidth, and BitOffset. * ******************************************************************************/ ACPI_STATUS AcpiHwValidateRegister ( ACPI_GENERIC_ADDRESS *Reg, UINT8 MaxBitWidth, UINT64 *Address) { UINT8 BitWidth; UINT8 AccessWidth; /* Must have a valid pointer to a GAS structure */ if (!Reg) { return (AE_BAD_PARAMETER); } /* * Copy the target address. This handles possible alignment issues. * Address must not be null. A null address also indicates an optional * ACPI register that is not supported, so no error message. */ ACPI_MOVE_64_TO_64 (Address, &Reg->Address); if (!(*Address)) { return (AE_BAD_ADDRESS); } /* Validate the SpaceID */ if ((Reg->SpaceId != ACPI_ADR_SPACE_SYSTEM_MEMORY) && (Reg->SpaceId != ACPI_ADR_SPACE_SYSTEM_IO)) { ACPI_ERROR ((AE_INFO, "Unsupported address space: 0x%X", Reg->SpaceId)); return (AE_SUPPORT); } /* Validate the AccessWidth */ if (Reg->AccessWidth > 4) { ACPI_ERROR ((AE_INFO, "Unsupported register access width: 0x%X", Reg->AccessWidth)); return (AE_SUPPORT); } /* Validate the BitWidth, convert AccessWidth into number of bits */ AccessWidth = AcpiHwGetAccessBitWidth (*Address, Reg, MaxBitWidth); BitWidth = ACPI_ROUND_UP (Reg->BitOffset + Reg->BitWidth, AccessWidth); if (MaxBitWidth < BitWidth) { ACPI_WARNING ((AE_INFO, "Requested bit width 0x%X is smaller than register bit width 0x%X", MaxBitWidth, BitWidth)); return (AE_SUPPORT); } return (AE_OK); } /****************************************************************************** * * FUNCTION: AcpiHwRead * * PARAMETERS: Value - Where the value is returned * Reg - GAS register structure * * RETURN: Status * * DESCRIPTION: Read from either memory or IO space. This is a 64-bit max * version of AcpiRead. * * LIMITATIONS: * SpaceID must be SystemMemory or SystemIO. * ******************************************************************************/ ACPI_STATUS AcpiHwRead ( UINT64 *Value, ACPI_GENERIC_ADDRESS *Reg) { UINT64 Address; UINT8 AccessWidth; UINT32 BitWidth; UINT8 BitOffset; UINT64 Value64; UINT32 Value32; UINT8 Index; ACPI_STATUS Status; ACPI_FUNCTION_NAME (HwRead); /* Validate contents of the GAS register */ Status = AcpiHwValidateRegister (Reg, 64, &Address); if (ACPI_FAILURE (Status)) { return (Status); } /* * Initialize entire 64-bit return value to zero, convert AccessWidth * into number of bits based */ *Value = 0; AccessWidth = AcpiHwGetAccessBitWidth (Address, Reg, 64); BitWidth = Reg->BitOffset + Reg->BitWidth; BitOffset = Reg->BitOffset; /* * Two address spaces supported: Memory or IO. PCI_Config is * not supported here because the GAS structure is insufficient */ Index = 0; while (BitWidth) { if (BitOffset >= AccessWidth) { Value64 = 0; BitOffset -= AccessWidth; } else { if (Reg->SpaceId == ACPI_ADR_SPACE_SYSTEM_MEMORY) { Status = AcpiOsReadMemory ((ACPI_PHYSICAL_ADDRESS) Address + Index * ACPI_DIV_8 (AccessWidth), &Value64, AccessWidth); } else /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */ { Status = AcpiHwReadPort ((ACPI_IO_ADDRESS) Address + Index * ACPI_DIV_8 (AccessWidth), &Value32, AccessWidth); Value64 = (UINT64) Value32; } } /* * Use offset style bit writes because "Index * AccessWidth" is * ensured to be less than 64-bits by AcpiHwValidateRegister(). */ ACPI_SET_BITS (Value, Index * AccessWidth, ACPI_MASK_BITS_ABOVE_64 (AccessWidth), Value64); BitWidth -= BitWidth > AccessWidth ? AccessWidth : BitWidth; Index++; } ACPI_DEBUG_PRINT ((ACPI_DB_IO, "Read: %8.8X%8.8X width %2d from %8.8X%8.8X (%s)\n", ACPI_FORMAT_UINT64 (*Value), AccessWidth, ACPI_FORMAT_UINT64 (Address), AcpiUtGetRegionName (Reg->SpaceId))); return (Status); } /****************************************************************************** * * FUNCTION: AcpiHwWrite * * PARAMETERS: Value - Value to be written * Reg - GAS register structure * * RETURN: Status * * DESCRIPTION: Write to either memory or IO space. This is a 64-bit max * version of AcpiWrite. * ******************************************************************************/ ACPI_STATUS AcpiHwWrite ( UINT64 Value, ACPI_GENERIC_ADDRESS *Reg) { UINT64 Address; UINT8 AccessWidth; UINT32 BitWidth; UINT8 BitOffset; UINT64 Value64; UINT8 Index; ACPI_STATUS Status; ACPI_FUNCTION_NAME (HwWrite); /* Validate contents of the GAS register */ Status = AcpiHwValidateRegister (Reg, 64, &Address); if (ACPI_FAILURE (Status)) { return (Status); } /* Convert AccessWidth into number of bits based */ AccessWidth = AcpiHwGetAccessBitWidth (Address, Reg, 64); BitWidth = Reg->BitOffset + Reg->BitWidth; BitOffset = Reg->BitOffset; /* * Two address spaces supported: Memory or IO. PCI_Config is * not supported here because the GAS structure is insufficient */ Index = 0; while (BitWidth) { /* * Use offset style bit reads because "Index * AccessWidth" is * ensured to be less than 64-bits by AcpiHwValidateRegister(). */ Value64 = ACPI_GET_BITS (&Value, Index * AccessWidth, ACPI_MASK_BITS_ABOVE_64 (AccessWidth)); if (BitOffset >= AccessWidth) { BitOffset -= AccessWidth; } else { if (Reg->SpaceId == ACPI_ADR_SPACE_SYSTEM_MEMORY) { Status = AcpiOsWriteMemory ((ACPI_PHYSICAL_ADDRESS) Address + Index * ACPI_DIV_8 (AccessWidth), Value64, AccessWidth); } else /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */ { Status = AcpiHwWritePort ((ACPI_IO_ADDRESS) Address + Index * ACPI_DIV_8 (AccessWidth), (UINT32) Value64, AccessWidth); } } /* * Index * AccessWidth is ensured to be less than 32-bits by * AcpiHwValidateRegister(). */ BitWidth -= BitWidth > AccessWidth ? AccessWidth : BitWidth; Index++; } ACPI_DEBUG_PRINT ((ACPI_DB_IO, "Wrote: %8.8X%8.8X width %2d to %8.8X%8.8X (%s)\n", ACPI_FORMAT_UINT64 (Value), AccessWidth, ACPI_FORMAT_UINT64 (Address), AcpiUtGetRegionName (Reg->SpaceId))); return (Status); } #if (!ACPI_REDUCED_HARDWARE) /******************************************************************************* * * FUNCTION: AcpiHwClearAcpiStatus * * PARAMETERS: None * * RETURN: Status * * DESCRIPTION: Clears all fixed and general purpose status bits * ******************************************************************************/ ACPI_STATUS AcpiHwClearAcpiStatus ( void) { ACPI_STATUS Status; ACPI_CPU_FLAGS LockFlags = 0; ACPI_FUNCTION_TRACE (HwClearAcpiStatus); ACPI_DEBUG_PRINT ((ACPI_DB_IO, "About to write %04X to %8.8X%8.8X\n", ACPI_BITMASK_ALL_FIXED_STATUS, ACPI_FORMAT_UINT64 (AcpiGbl_XPm1aStatus.Address))); LockFlags = AcpiOsAcquireLock (AcpiGbl_HardwareLock); /* Clear the fixed events in PM1 A/B */ Status = AcpiHwRegisterWrite (ACPI_REGISTER_PM1_STATUS, ACPI_BITMASK_ALL_FIXED_STATUS); AcpiOsReleaseLock (AcpiGbl_HardwareLock, LockFlags); if (ACPI_FAILURE (Status)) { goto Exit; } /* Clear the GPE Bits in all GPE registers in all GPE blocks */ Status = AcpiEvWalkGpeList (AcpiHwClearGpeBlock, NULL); Exit: return_ACPI_STATUS (Status); } /******************************************************************************* * * FUNCTION: AcpiHwGetBitRegisterInfo * * PARAMETERS: RegisterId - Index of ACPI Register to access * * RETURN: The bitmask to be used when accessing the register * * DESCRIPTION: Map RegisterId into a register bitmask. * ******************************************************************************/ ACPI_BIT_REGISTER_INFO * AcpiHwGetBitRegisterInfo ( UINT32 RegisterId) { ACPI_FUNCTION_ENTRY (); if (RegisterId > ACPI_BITREG_MAX) { ACPI_ERROR ((AE_INFO, "Invalid BitRegister ID: 0x%X", RegisterId)); return (NULL); } return (&AcpiGbl_BitRegisterInfo[RegisterId]); } /****************************************************************************** * * FUNCTION: AcpiHwWritePm1Control * * PARAMETERS: Pm1aControl - Value to be written to PM1A control * Pm1bControl - Value to be written to PM1B control * * RETURN: Status * * DESCRIPTION: Write the PM1 A/B control registers. These registers are * different than the PM1 A/B status and enable registers * in that different values can be written to the A/B registers. * Most notably, the SLP_TYP bits can be different, as per the * values returned from the _Sx predefined methods. * ******************************************************************************/ ACPI_STATUS AcpiHwWritePm1Control ( UINT32 Pm1aControl, UINT32 Pm1bControl) { ACPI_STATUS Status; ACPI_FUNCTION_TRACE (HwWritePm1Control); Status = AcpiHwWrite (Pm1aControl, &AcpiGbl_FADT.XPm1aControlBlock); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } if (AcpiGbl_FADT.XPm1bControlBlock.Address) { Status = AcpiHwWrite (Pm1bControl, &AcpiGbl_FADT.XPm1bControlBlock); } return_ACPI_STATUS (Status); } /****************************************************************************** * * FUNCTION: AcpiHwRegisterRead * * PARAMETERS: RegisterId - ACPI Register ID * ReturnValue - Where the register value is returned * * RETURN: Status and the value read. * * DESCRIPTION: Read from the specified ACPI register * ******************************************************************************/ ACPI_STATUS AcpiHwRegisterRead ( UINT32 RegisterId, UINT32 *ReturnValue) { UINT32 Value = 0; UINT64 Value64; ACPI_STATUS Status; ACPI_FUNCTION_TRACE (HwRegisterRead); switch (RegisterId) { case ACPI_REGISTER_PM1_STATUS: /* PM1 A/B: 16-bit access each */ Status = AcpiHwReadMultiple (&Value, &AcpiGbl_XPm1aStatus, &AcpiGbl_XPm1bStatus); break; case ACPI_REGISTER_PM1_ENABLE: /* PM1 A/B: 16-bit access each */ Status = AcpiHwReadMultiple (&Value, &AcpiGbl_XPm1aEnable, &AcpiGbl_XPm1bEnable); break; case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */ Status = AcpiHwReadMultiple (&Value, &AcpiGbl_FADT.XPm1aControlBlock, &AcpiGbl_FADT.XPm1bControlBlock); /* * 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 = AcpiHwRead (&Value64, &AcpiGbl_FADT.XPm2ControlBlock); if (ACPI_SUCCESS (Status)) { Value = (UINT32) Value64; } break; case ACPI_REGISTER_PM_TIMER: /* 32-bit access */ Status = AcpiHwRead (&Value64, &AcpiGbl_FADT.XPmTimerBlock); if (ACPI_SUCCESS (Status)) { Value = (UINT32) Value64; } break; case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */ Status = AcpiHwReadPort (AcpiGbl_FADT.SmiCommand, &Value, 8); break; default: ACPI_ERROR ((AE_INFO, "Unknown Register ID: 0x%X", RegisterId)); Status = AE_BAD_PARAMETER; break; } if (ACPI_SUCCESS (Status)) { *ReturnValue = (UINT32) Value; } return_ACPI_STATUS (Status); } /****************************************************************************** * * FUNCTION: AcpiHwRegisterWrite * * PARAMETERS: RegisterId - 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 AcpiHwRegisterWrite ( UINT32 RegisterId, UINT32 Value) { ACPI_STATUS Status; UINT32 ReadValue; UINT64 ReadValue64; ACPI_FUNCTION_TRACE (HwRegisterWrite); switch (RegisterId) { 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 = AcpiHwWriteMultiple (Value, &AcpiGbl_XPm1aStatus, &AcpiGbl_XPm1bStatus); break; case ACPI_REGISTER_PM1_ENABLE: /* PM1 A/B: 16-bit access each */ Status = AcpiHwWriteMultiple (Value, &AcpiGbl_XPm1aEnable, &AcpiGbl_XPm1bEnable); 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 = AcpiHwReadMultiple (&ReadValue, &AcpiGbl_FADT.XPm1aControlBlock, &AcpiGbl_FADT.XPm1bControlBlock); if (ACPI_FAILURE (Status)) { goto Exit; } /* Insert the bits to be preserved */ ACPI_INSERT_BITS (Value, ACPI_PM1_CONTROL_PRESERVED_BITS, ReadValue); /* Now we can write the data */ Status = AcpiHwWriteMultiple (Value, &AcpiGbl_FADT.XPm1aControlBlock, &AcpiGbl_FADT.XPm1bControlBlock); break; case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */ /* * For control registers, all reserved bits must be preserved, * as per the ACPI spec. */ Status = AcpiHwRead (&ReadValue64, &AcpiGbl_FADT.XPm2ControlBlock); if (ACPI_FAILURE (Status)) { goto Exit; } ReadValue = (UINT32) ReadValue64; /* Insert the bits to be preserved */ ACPI_INSERT_BITS (Value, ACPI_PM2_CONTROL_PRESERVED_BITS, ReadValue); Status = AcpiHwWrite (Value, &AcpiGbl_FADT.XPm2ControlBlock); break; case ACPI_REGISTER_PM_TIMER: /* 32-bit access */ Status = AcpiHwWrite (Value, &AcpiGbl_FADT.XPmTimerBlock); break; case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */ /* SMI_CMD is currently always in IO space */ Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand, Value, 8); break; default: ACPI_ERROR ((AE_INFO, "Unknown Register ID: 0x%X", RegisterId)); Status = AE_BAD_PARAMETER; break; } Exit: return_ACPI_STATUS (Status); } /****************************************************************************** * * FUNCTION: AcpiHwReadMultiple * * PARAMETERS: Value - Where the register value is returned * RegisterA - First ACPI register (required) * RegisterB - Second ACPI register (optional) * * RETURN: Status * * DESCRIPTION: Read from the specified two-part ACPI register (such as PM1 A/B) * ******************************************************************************/ static ACPI_STATUS AcpiHwReadMultiple ( UINT32 *Value, ACPI_GENERIC_ADDRESS *RegisterA, ACPI_GENERIC_ADDRESS *RegisterB) { UINT32 ValueA = 0; UINT32 ValueB = 0; UINT64 Value64; ACPI_STATUS Status; /* The first register is always required */ Status = AcpiHwRead (&Value64, RegisterA); if (ACPI_FAILURE (Status)) { return (Status); } ValueA = (UINT32) Value64; /* Second register is optional */ if (RegisterB->Address) { Status = AcpiHwRead (&Value64, RegisterB); if (ACPI_FAILURE (Status)) { return (Status); } ValueB = (UINT32) 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 = (ValueA | ValueB); return (AE_OK); } /****************************************************************************** * * FUNCTION: AcpiHwWriteMultiple * * PARAMETERS: Value - The value to write * RegisterA - First ACPI register (required) * RegisterB - Second ACPI register (optional) * * RETURN: Status * * DESCRIPTION: Write to the specified two-part ACPI register (such as PM1 A/B) * ******************************************************************************/ static ACPI_STATUS AcpiHwWriteMultiple ( UINT32 Value, ACPI_GENERIC_ADDRESS *RegisterA, ACPI_GENERIC_ADDRESS *RegisterB) { ACPI_STATUS Status; /* The first register is always required */ Status = AcpiHwWrite (Value, RegisterA); 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 (RegisterB->Address) { Status = AcpiHwWrite (Value, RegisterB); } return (Status); } #endif /* !ACPI_REDUCED_HARDWARE */