/****************************************************************************** * * Module Name: exfldio - Aml Field I/O * *****************************************************************************/ /* * Copyright (C) 2000 - 2013, Intel Corp. * All rights reserved. * * 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. * * Alternatively, this software may be distributed under the terms of the * GNU General Public License ("GPL") version 2 as published by the Free * Software Foundation. * * NO WARRANTY * 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 MERCHANTIBILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES. */ #define __EXFLDIO_C__ #include #include #include #include #include #include #define _COMPONENT ACPI_EXECUTER ACPI_MODULE_NAME ("exfldio") /* Local prototypes */ static ACPI_STATUS AcpiExFieldDatumIo ( ACPI_OPERAND_OBJECT *ObjDesc, UINT32 FieldDatumByteOffset, UINT64 *Value, UINT32 ReadWrite); static BOOLEAN AcpiExRegisterOverflow ( ACPI_OPERAND_OBJECT *ObjDesc, UINT64 Value); static ACPI_STATUS AcpiExSetupRegion ( ACPI_OPERAND_OBJECT *ObjDesc, UINT32 FieldDatumByteOffset); /******************************************************************************* * * FUNCTION: AcpiExSetupRegion * * PARAMETERS: ObjDesc - Field to be read or written * FieldDatumByteOffset - Byte offset of this datum within the * parent field * * RETURN: Status * * DESCRIPTION: Common processing for AcpiExExtractFromField and * AcpiExInsertIntoField. Initialize the Region if necessary and * validate the request. * ******************************************************************************/ static ACPI_STATUS AcpiExSetupRegion ( ACPI_OPERAND_OBJECT *ObjDesc, UINT32 FieldDatumByteOffset) { ACPI_STATUS Status = AE_OK; ACPI_OPERAND_OBJECT *RgnDesc; UINT8 SpaceId; ACPI_FUNCTION_TRACE_U32 (ExSetupRegion, FieldDatumByteOffset); RgnDesc = ObjDesc->CommonField.RegionObj; /* We must have a valid region */ if (RgnDesc->Common.Type != ACPI_TYPE_REGION) { ACPI_ERROR ((AE_INFO, "Needed Region, found type 0x%X (%s)", RgnDesc->Common.Type, AcpiUtGetObjectTypeName (RgnDesc))); return_ACPI_STATUS (AE_AML_OPERAND_TYPE); } SpaceId = RgnDesc->Region.SpaceId; /* Validate the Space ID */ if (!AcpiIsValidSpaceId (SpaceId)) { ACPI_ERROR ((AE_INFO, "Invalid/unknown Address Space ID: 0x%2.2X", SpaceId)); return_ACPI_STATUS (AE_AML_INVALID_SPACE_ID); } /* * If the Region Address and Length have not been previously evaluated, * evaluate them now and save the results. */ if (!(RgnDesc->Common.Flags & AOPOBJ_DATA_VALID)) { Status = AcpiDsGetRegionArguments (RgnDesc); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } } /* * Exit now for SMBus, GSBus or IPMI address space, it has a non-linear * address space and the request cannot be directly validated */ if (SpaceId == ACPI_ADR_SPACE_SMBUS || SpaceId == ACPI_ADR_SPACE_GSBUS || SpaceId == ACPI_ADR_SPACE_IPMI) { /* SMBus or IPMI has a non-linear address space */ return_ACPI_STATUS (AE_OK); } #ifdef ACPI_UNDER_DEVELOPMENT /* * If the Field access is AnyAcc, we can now compute the optimal * access (because we know know the length of the parent region) */ if (!(ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)) { if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } } #endif /* * Validate the request. The entire request from the byte offset for a * length of one field datum (access width) must fit within the region. * (Region length is specified in bytes) */ if (RgnDesc->Region.Length < (ObjDesc->CommonField.BaseByteOffset + FieldDatumByteOffset + ObjDesc->CommonField.AccessByteWidth)) { if (AcpiGbl_EnableInterpreterSlack) { /* * Slack mode only: We will go ahead and allow access to this * field if it is within the region length rounded up to the next * access width boundary. ACPI_SIZE cast for 64-bit compile. */ if (ACPI_ROUND_UP (RgnDesc->Region.Length, ObjDesc->CommonField.AccessByteWidth) >= ((ACPI_SIZE) ObjDesc->CommonField.BaseByteOffset + ObjDesc->CommonField.AccessByteWidth + FieldDatumByteOffset)) { return_ACPI_STATUS (AE_OK); } } if (RgnDesc->Region.Length < ObjDesc->CommonField.AccessByteWidth) { /* * This is the case where the AccessType (AccWord, etc.) is wider * than the region itself. For example, a region of length one * byte, and a field with Dword access specified. */ ACPI_ERROR ((AE_INFO, "Field [%4.4s] access width (%u bytes) too large for region [%4.4s] (length %u)", AcpiUtGetNodeName (ObjDesc->CommonField.Node), ObjDesc->CommonField.AccessByteWidth, AcpiUtGetNodeName (RgnDesc->Region.Node), RgnDesc->Region.Length)); } /* * Offset rounded up to next multiple of field width * exceeds region length, indicate an error */ ACPI_ERROR ((AE_INFO, "Field [%4.4s] Base+Offset+Width %u+%u+%u is beyond end of region [%4.4s] (length %u)", AcpiUtGetNodeName (ObjDesc->CommonField.Node), ObjDesc->CommonField.BaseByteOffset, FieldDatumByteOffset, ObjDesc->CommonField.AccessByteWidth, AcpiUtGetNodeName (RgnDesc->Region.Node), RgnDesc->Region.Length)); return_ACPI_STATUS (AE_AML_REGION_LIMIT); } return_ACPI_STATUS (AE_OK); } /******************************************************************************* * * FUNCTION: AcpiExAccessRegion * * PARAMETERS: ObjDesc - Field to be read * FieldDatumByteOffset - Byte offset of this datum within the * parent field * Value - Where to store value (must at least * 64 bits) * Function - Read or Write flag plus other region- * dependent flags * * RETURN: Status * * DESCRIPTION: Read or Write a single field datum to an Operation Region. * ******************************************************************************/ ACPI_STATUS AcpiExAccessRegion ( ACPI_OPERAND_OBJECT *ObjDesc, UINT32 FieldDatumByteOffset, UINT64 *Value, UINT32 Function) { ACPI_STATUS Status; ACPI_OPERAND_OBJECT *RgnDesc; UINT32 RegionOffset; ACPI_FUNCTION_TRACE (ExAccessRegion); /* * Ensure that the region operands are fully evaluated and verify * the validity of the request */ Status = AcpiExSetupRegion (ObjDesc, FieldDatumByteOffset); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } /* * The physical address of this field datum is: * * 1) The base of the region, plus * 2) The base offset of the field, plus * 3) The current offset into the field */ RgnDesc = ObjDesc->CommonField.RegionObj; RegionOffset = ObjDesc->CommonField.BaseByteOffset + FieldDatumByteOffset; if ((Function & ACPI_IO_MASK) == ACPI_READ) { ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[READ]")); } else { ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[WRITE]")); } ACPI_DEBUG_PRINT_RAW ((ACPI_DB_BFIELD, " Region [%s:%X], Width %X, ByteBase %X, Offset %X at %p\n", AcpiUtGetRegionName (RgnDesc->Region.SpaceId), RgnDesc->Region.SpaceId, ObjDesc->CommonField.AccessByteWidth, ObjDesc->CommonField.BaseByteOffset, FieldDatumByteOffset, ACPI_CAST_PTR (void, (RgnDesc->Region.Address + RegionOffset)))); /* Invoke the appropriate AddressSpace/OpRegion handler */ Status = AcpiEvAddressSpaceDispatch (RgnDesc, ObjDesc, Function, RegionOffset, ACPI_MUL_8 (ObjDesc->CommonField.AccessByteWidth), Value); if (ACPI_FAILURE (Status)) { if (Status == AE_NOT_IMPLEMENTED) { ACPI_ERROR ((AE_INFO, "Region %s (ID=%u) not implemented", AcpiUtGetRegionName (RgnDesc->Region.SpaceId), RgnDesc->Region.SpaceId)); } else if (Status == AE_NOT_EXIST) { ACPI_ERROR ((AE_INFO, "Region %s (ID=%u) has no handler", AcpiUtGetRegionName (RgnDesc->Region.SpaceId), RgnDesc->Region.SpaceId)); } } return_ACPI_STATUS (Status); } /******************************************************************************* * * FUNCTION: AcpiExRegisterOverflow * * PARAMETERS: ObjDesc - Register(Field) to be written * Value - Value to be stored * * RETURN: TRUE if value overflows the field, FALSE otherwise * * DESCRIPTION: Check if a value is out of range of the field being written. * Used to check if the values written to Index and Bank registers * are out of range. Normally, the value is simply truncated * to fit the field, but this case is most likely a serious * coding error in the ASL. * ******************************************************************************/ static BOOLEAN AcpiExRegisterOverflow ( ACPI_OPERAND_OBJECT *ObjDesc, UINT64 Value) { if (ObjDesc->CommonField.BitLength >= ACPI_INTEGER_BIT_SIZE) { /* * The field is large enough to hold the maximum integer, so we can * never overflow it. */ return (FALSE); } if (Value >= ((UINT64) 1 << ObjDesc->CommonField.BitLength)) { /* * The Value is larger than the maximum value that can fit into * the register. */ ACPI_ERROR ((AE_INFO, "Index value 0x%8.8X%8.8X overflows field width 0x%X", ACPI_FORMAT_UINT64 (Value), ObjDesc->CommonField.BitLength)); return (TRUE); } /* The Value will fit into the field with no truncation */ return (FALSE); } /******************************************************************************* * * FUNCTION: AcpiExFieldDatumIo * * PARAMETERS: ObjDesc - Field to be read * FieldDatumByteOffset - Byte offset of this datum within the * parent field * Value - Where to store value (must be 64 bits) * ReadWrite - Read or Write flag * * RETURN: Status * * DESCRIPTION: Read or Write a single datum of a field. The FieldType is * demultiplexed here to handle the different types of fields * (BufferField, RegionField, IndexField, BankField) * ******************************************************************************/ static ACPI_STATUS AcpiExFieldDatumIo ( ACPI_OPERAND_OBJECT *ObjDesc, UINT32 FieldDatumByteOffset, UINT64 *Value, UINT32 ReadWrite) { ACPI_STATUS Status; UINT64 LocalValue; ACPI_FUNCTION_TRACE_U32 (ExFieldDatumIo, FieldDatumByteOffset); if (ReadWrite == ACPI_READ) { if (!Value) { LocalValue = 0; /* To support reads without saving return value */ Value = &LocalValue; } /* Clear the entire return buffer first, [Very Important!] */ *Value = 0; } /* * The four types of fields are: * * BufferField - Read/write from/to a Buffer * RegionField - Read/write from/to a Operation Region. * BankField - Write to a Bank Register, then read/write from/to an * OperationRegion * IndexField - Write to an Index Register, then read/write from/to a * Data Register */ switch (ObjDesc->Common.Type) { case ACPI_TYPE_BUFFER_FIELD: /* * If the BufferField arguments have not been previously evaluated, * evaluate them now and save the results. */ if (!(ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)) { Status = AcpiDsGetBufferFieldArguments (ObjDesc); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } } if (ReadWrite == ACPI_READ) { /* * Copy the data from the source buffer. * Length is the field width in bytes. */ ACPI_MEMCPY (Value, (ObjDesc->BufferField.BufferObj)->Buffer.Pointer + ObjDesc->BufferField.BaseByteOffset + FieldDatumByteOffset, ObjDesc->CommonField.AccessByteWidth); } else { /* * Copy the data to the target buffer. * Length is the field width in bytes. */ ACPI_MEMCPY ((ObjDesc->BufferField.BufferObj)->Buffer.Pointer + ObjDesc->BufferField.BaseByteOffset + FieldDatumByteOffset, Value, ObjDesc->CommonField.AccessByteWidth); } Status = AE_OK; break; case ACPI_TYPE_LOCAL_BANK_FIELD: /* * Ensure that the BankValue is not beyond the capacity of * the register */ if (AcpiExRegisterOverflow (ObjDesc->BankField.BankObj, (UINT64) ObjDesc->BankField.Value)) { return_ACPI_STATUS (AE_AML_REGISTER_LIMIT); } /* * For BankFields, we must write the BankValue to the BankRegister * (itself a RegionField) before we can access the data. */ Status = AcpiExInsertIntoField (ObjDesc->BankField.BankObj, &ObjDesc->BankField.Value, sizeof (ObjDesc->BankField.Value)); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } /* * Now that the Bank has been selected, fall through to the * RegionField case and write the datum to the Operation Region */ /*lint -fallthrough */ case ACPI_TYPE_LOCAL_REGION_FIELD: /* * For simple RegionFields, we just directly access the owning * Operation Region. */ Status = AcpiExAccessRegion (ObjDesc, FieldDatumByteOffset, Value, ReadWrite); break; case ACPI_TYPE_LOCAL_INDEX_FIELD: /* * Ensure that the IndexValue is not beyond the capacity of * the register */ if (AcpiExRegisterOverflow (ObjDesc->IndexField.IndexObj, (UINT64) ObjDesc->IndexField.Value)) { return_ACPI_STATUS (AE_AML_REGISTER_LIMIT); } /* Write the index value to the IndexRegister (itself a RegionField) */ FieldDatumByteOffset += ObjDesc->IndexField.Value; ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Write to Index Register: Value %8.8X\n", FieldDatumByteOffset)); Status = AcpiExInsertIntoField (ObjDesc->IndexField.IndexObj, &FieldDatumByteOffset, sizeof (FieldDatumByteOffset)); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } if (ReadWrite == ACPI_READ) { /* Read the datum from the DataRegister */ ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Read from Data Register\n")); Status = AcpiExExtractFromField (ObjDesc->IndexField.DataObj, Value, sizeof (UINT64)); } else { /* Write the datum to the DataRegister */ ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Write to Data Register: Value %8.8X%8.8X\n", ACPI_FORMAT_UINT64 (*Value))); Status = AcpiExInsertIntoField (ObjDesc->IndexField.DataObj, Value, sizeof (UINT64)); } break; default: ACPI_ERROR ((AE_INFO, "Wrong object type in field I/O %u", ObjDesc->Common.Type)); Status = AE_AML_INTERNAL; break; } if (ACPI_SUCCESS (Status)) { if (ReadWrite == ACPI_READ) { ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Read %8.8X%8.8X, Width %u\n", ACPI_FORMAT_UINT64 (*Value), ObjDesc->CommonField.AccessByteWidth)); } else { ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Written %8.8X%8.8X, Width %u\n", ACPI_FORMAT_UINT64 (*Value), ObjDesc->CommonField.AccessByteWidth)); } } return_ACPI_STATUS (Status); } /******************************************************************************* * * FUNCTION: AcpiExWriteWithUpdateRule * * PARAMETERS: ObjDesc - Field to be written * Mask - bitmask within field datum * FieldValue - Value to write * FieldDatumByteOffset - Offset of datum within field * * RETURN: Status * * DESCRIPTION: Apply the field update rule to a field write * ******************************************************************************/ ACPI_STATUS AcpiExWriteWithUpdateRule ( ACPI_OPERAND_OBJECT *ObjDesc, UINT64 Mask, UINT64 FieldValue, UINT32 FieldDatumByteOffset) { ACPI_STATUS Status = AE_OK; UINT64 MergedValue; UINT64 CurrentValue; ACPI_FUNCTION_TRACE_U32 (ExWriteWithUpdateRule, Mask); /* Start with the new bits */ MergedValue = FieldValue; /* If the mask is all ones, we don't need to worry about the update rule */ if (Mask != ACPI_UINT64_MAX) { /* Decode the update rule */ switch (ObjDesc->CommonField.FieldFlags & AML_FIELD_UPDATE_RULE_MASK) { case AML_FIELD_UPDATE_PRESERVE: /* * Check if update rule needs to be applied (not if mask is all * ones) The left shift drops the bits we want to ignore. */ if ((~Mask << (ACPI_MUL_8 (sizeof (Mask)) - ACPI_MUL_8 (ObjDesc->CommonField.AccessByteWidth))) != 0) { /* * Read the current contents of the byte/word/dword containing * the field, and merge with the new field value. */ Status = AcpiExFieldDatumIo (ObjDesc, FieldDatumByteOffset, &CurrentValue, ACPI_READ); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } MergedValue |= (CurrentValue & ~Mask); } break; case AML_FIELD_UPDATE_WRITE_AS_ONES: /* Set positions outside the field to all ones */ MergedValue |= ~Mask; break; case AML_FIELD_UPDATE_WRITE_AS_ZEROS: /* Set positions outside the field to all zeros */ MergedValue &= Mask; break; default: ACPI_ERROR ((AE_INFO, "Unknown UpdateRule value: 0x%X", (ObjDesc->CommonField.FieldFlags & AML_FIELD_UPDATE_RULE_MASK))); return_ACPI_STATUS (AE_AML_OPERAND_VALUE); } } ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Mask %8.8X%8.8X, DatumOffset %X, Width %X, Value %8.8X%8.8X, MergedValue %8.8X%8.8X\n", ACPI_FORMAT_UINT64 (Mask), FieldDatumByteOffset, ObjDesc->CommonField.AccessByteWidth, ACPI_FORMAT_UINT64 (FieldValue), ACPI_FORMAT_UINT64 (MergedValue))); /* Write the merged value */ Status = AcpiExFieldDatumIo (ObjDesc, FieldDatumByteOffset, &MergedValue, ACPI_WRITE); return_ACPI_STATUS (Status); } /******************************************************************************* * * FUNCTION: AcpiExExtractFromField * * PARAMETERS: ObjDesc - Field to be read * Buffer - Where to store the field data * BufferLength - Length of Buffer * * RETURN: Status * * DESCRIPTION: Retrieve the current value of the given field * ******************************************************************************/ ACPI_STATUS AcpiExExtractFromField ( ACPI_OPERAND_OBJECT *ObjDesc, void *Buffer, UINT32 BufferLength) { ACPI_STATUS Status; UINT64 RawDatum; UINT64 MergedDatum; UINT32 FieldOffset = 0; UINT32 BufferOffset = 0; UINT32 BufferTailBits; UINT32 DatumCount; UINT32 FieldDatumCount; UINT32 AccessBitWidth; UINT32 i; ACPI_FUNCTION_TRACE (ExExtractFromField); /* Validate target buffer and clear it */ if (BufferLength < ACPI_ROUND_BITS_UP_TO_BYTES (ObjDesc->CommonField.BitLength)) { ACPI_ERROR ((AE_INFO, "Field size %u (bits) is too large for buffer (%u)", ObjDesc->CommonField.BitLength, BufferLength)); return_ACPI_STATUS (AE_BUFFER_OVERFLOW); } ACPI_MEMSET (Buffer, 0, BufferLength); AccessBitWidth = ACPI_MUL_8 (ObjDesc->CommonField.AccessByteWidth); /* Handle the simple case here */ if ((ObjDesc->CommonField.StartFieldBitOffset == 0) && (ObjDesc->CommonField.BitLength == AccessBitWidth)) { if (BufferLength >= sizeof (UINT64)) { Status = AcpiExFieldDatumIo (ObjDesc, 0, Buffer, ACPI_READ); } else { /* Use RawDatum (UINT64) to handle buffers < 64 bits */ Status = AcpiExFieldDatumIo (ObjDesc, 0, &RawDatum, ACPI_READ); ACPI_MEMCPY (Buffer, &RawDatum, BufferLength); } return_ACPI_STATUS (Status); } /* TBD: Move to common setup code */ /* Field algorithm is limited to sizeof(UINT64), truncate if needed */ if (ObjDesc->CommonField.AccessByteWidth > sizeof (UINT64)) { ObjDesc->CommonField.AccessByteWidth = sizeof (UINT64); AccessBitWidth = sizeof (UINT64) * 8; } /* Compute the number of datums (access width data items) */ DatumCount = ACPI_ROUND_UP_TO ( ObjDesc->CommonField.BitLength, AccessBitWidth); FieldDatumCount = ACPI_ROUND_UP_TO ( ObjDesc->CommonField.BitLength + ObjDesc->CommonField.StartFieldBitOffset, AccessBitWidth); /* Priming read from the field */ Status = AcpiExFieldDatumIo (ObjDesc, FieldOffset, &RawDatum, ACPI_READ); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } MergedDatum = RawDatum >> ObjDesc->CommonField.StartFieldBitOffset; /* Read the rest of the field */ for (i = 1; i < FieldDatumCount; i++) { /* Get next input datum from the field */ FieldOffset += ObjDesc->CommonField.AccessByteWidth; Status = AcpiExFieldDatumIo (ObjDesc, FieldOffset, &RawDatum, ACPI_READ); if (ACPI_FAILURE (Status)) { return_ACPI_STATUS (Status); } /* * Merge with previous datum if necessary. * * Note: Before the shift, check if the shift value will be larger than * the integer size. If so, there is no need to perform the operation. * This avoids the differences in behavior between different compilers * concerning shift values larger than the target data width. */ if (AccessBitWidth - ObjDesc->CommonField.StartFieldBitOffset < ACPI_INTEGER_BIT_SIZE) { MergedDatum |= RawDatum << (AccessBitWidth - ObjDesc->CommonField.StartFieldBitOffset); } if (i == DatumCount) { break; } /* Write merged datum to target buffer */ ACPI_MEMCPY (((char *) Buffer) + BufferOffset, &MergedDatum, ACPI_MIN(ObjDesc->CommonField.AccessByteWidth, BufferLength - BufferOffset)); BufferOffset += ObjDesc->CommonField.AccessByteWidth; MergedDatum = RawDatum >> ObjDesc->CommonField.StartFieldBitOffset; } /* Mask off any extra bits in the last datum */ BufferTailBits = ObjDesc->CommonField.BitLength % AccessBitWidth; if (BufferTailBits) { MergedDatum &= ACPI_MASK_BITS_ABOVE (BufferTailBits); } /* Write the last datum to the buffer */ ACPI_MEMCPY (((char *) Buffer) + BufferOffset, &MergedDatum, ACPI_MIN(ObjDesc->CommonField.AccessByteWidth, BufferLength - BufferOffset)); return_ACPI_STATUS (AE_OK); } /******************************************************************************* * * FUNCTION: AcpiExInsertIntoField * * PARAMETERS: ObjDesc - Field to be written * Buffer - Data to be written * BufferLength - Length of Buffer * * RETURN: Status * * DESCRIPTION: Store the Buffer contents into the given field * ******************************************************************************/ ACPI_STATUS AcpiExInsertIntoField ( ACPI_OPERAND_OBJECT *ObjDesc, void *Buffer, UINT32 BufferLength) { void *NewBuffer; ACPI_STATUS Status; UINT64 Mask; UINT64 WidthMask; UINT64 MergedDatum; UINT64 RawDatum = 0; UINT32 FieldOffset = 0; UINT32 BufferOffset = 0; UINT32 BufferTailBits; UINT32 DatumCount; UINT32 FieldDatumCount; UINT32 AccessBitWidth; UINT32 RequiredLength; UINT32 i; ACPI_FUNCTION_TRACE (ExInsertIntoField); /* Validate input buffer */ NewBuffer = NULL; RequiredLength = ACPI_ROUND_BITS_UP_TO_BYTES ( ObjDesc->CommonField.BitLength); /* * We must have a buffer that is at least as long as the field * we are writing to. This is because individual fields are * indivisible and partial writes are not supported -- as per * the ACPI specification. */ if (BufferLength < RequiredLength) { /* We need to create a new buffer */ NewBuffer = ACPI_ALLOCATE_ZEROED (RequiredLength); if (!NewBuffer) { return_ACPI_STATUS (AE_NO_MEMORY); } /* * Copy the original data to the new buffer, starting * at Byte zero. All unused (upper) bytes of the * buffer will be 0. */ ACPI_MEMCPY ((char *) NewBuffer, (char *) Buffer, BufferLength); Buffer = NewBuffer; BufferLength = RequiredLength; } /* TBD: Move to common setup code */ /* Algo is limited to sizeof(UINT64), so cut the AccessByteWidth */ if (ObjDesc->CommonField.AccessByteWidth > sizeof (UINT64)) { ObjDesc->CommonField.AccessByteWidth = sizeof (UINT64); } AccessBitWidth = ACPI_MUL_8 (ObjDesc->CommonField.AccessByteWidth); /* * Create the bitmasks used for bit insertion. * Note: This if/else is used to bypass compiler differences with the * shift operator */ if (AccessBitWidth == ACPI_INTEGER_BIT_SIZE) { WidthMask = ACPI_UINT64_MAX; } else { WidthMask = ACPI_MASK_BITS_ABOVE (AccessBitWidth); } Mask = WidthMask & ACPI_MASK_BITS_BELOW (ObjDesc->CommonField.StartFieldBitOffset); /* Compute the number of datums (access width data items) */ DatumCount = ACPI_ROUND_UP_TO (ObjDesc->CommonField.BitLength, AccessBitWidth); FieldDatumCount = ACPI_ROUND_UP_TO (ObjDesc->CommonField.BitLength + ObjDesc->CommonField.StartFieldBitOffset, AccessBitWidth); /* Get initial Datum from the input buffer */ ACPI_MEMCPY (&RawDatum, Buffer, ACPI_MIN(ObjDesc->CommonField.AccessByteWidth, BufferLength - BufferOffset)); MergedDatum = RawDatum << ObjDesc->CommonField.StartFieldBitOffset; /* Write the entire field */ for (i = 1; i < FieldDatumCount; i++) { /* Write merged datum to the target field */ MergedDatum &= Mask; Status = AcpiExWriteWithUpdateRule (ObjDesc, Mask, MergedDatum, FieldOffset); if (ACPI_FAILURE (Status)) { goto Exit; } FieldOffset += ObjDesc->CommonField.AccessByteWidth; /* * Start new output datum by merging with previous input datum * if necessary. * * Note: Before the shift, check if the shift value will be larger than * the integer size. If so, there is no need to perform the operation. * This avoids the differences in behavior between different compilers * concerning shift values larger than the target data width. */ if ((AccessBitWidth - ObjDesc->CommonField.StartFieldBitOffset) < ACPI_INTEGER_BIT_SIZE) { MergedDatum = RawDatum >> (AccessBitWidth - ObjDesc->CommonField.StartFieldBitOffset); } else { MergedDatum = 0; } Mask = WidthMask; if (i == DatumCount) { break; } /* Get the next input datum from the buffer */ BufferOffset += ObjDesc->CommonField.AccessByteWidth; ACPI_MEMCPY (&RawDatum, ((char *) Buffer) + BufferOffset, ACPI_MIN(ObjDesc->CommonField.AccessByteWidth, BufferLength - BufferOffset)); MergedDatum |= RawDatum << ObjDesc->CommonField.StartFieldBitOffset; } /* Mask off any extra bits in the last datum */ BufferTailBits = (ObjDesc->CommonField.BitLength + ObjDesc->CommonField.StartFieldBitOffset) % AccessBitWidth; if (BufferTailBits) { Mask &= ACPI_MASK_BITS_ABOVE (BufferTailBits); } /* Write the last datum to the field */ MergedDatum &= Mask; Status = AcpiExWriteWithUpdateRule (ObjDesc, Mask, MergedDatum, FieldOffset); Exit: /* Free temporary buffer if we used one */ if (NewBuffer) { ACPI_FREE (NewBuffer); } return_ACPI_STATUS (Status); }