rscalc.c

这个linux源代码是很全面的~基本完整了~使用c编译的~由于时间问题我没有亲自测试~但就算用来做参考资料也是非常好的

			 * optional elements.  Check the length of the
			 * Bytestream.  If it is greater than 23, that
			 * means that an Index exists and is followed by
			 * a null termininated string.  Therefore, set
			 * the temp variable to the length minus the minimum
			 * byte stream length plus the byte for the Index to
			 * determine the size of the NULL terminiated string.
			 */
			if (23 < temp16) {
				temp8 = (u8) (temp16 - 24);
			}
			else {
				temp8 = 0;
			}

			/*
			 * Ensure a 32-bit boundary for the structure
			 */
			temp8 = (u8) ROUND_UP_TO_32_bITS (temp8);

			structure_size = SIZEOF_RESOURCE (acpi_resource_address32) +
					   (temp8 * sizeof (u8));
			break;


		case RESOURCE_DESC_WORD_ADDRESS_SPACE:
			/*
			 * 16-Bit Address Resource
			 */
			buffer = byte_stream_buffer;

			++buffer;
			MOVE_UNALIGNED16_TO_16 (&temp16, buffer);

			bytes_consumed = temp16 + 3;

			/*
			 * Resource Source Index and Resource Source are
			 * optional elements.  Check the length of the
			 * Bytestream.  If it is greater than 13, that
			 * means that an Index exists and is followed by
			 * a null termininated string.  Therefore, set
			 * the temp variable to the length minus the minimum
			 * byte stream length plus the byte for the Index to
			 * determine the size of the NULL terminiated string.
			 */
			if (13 < temp16) {
				temp8 = (u8) (temp16 - 14);
			}
			else {
				temp8 = 0;
			}

			/*
			 * Ensure a 32-bit boundary for the structure
			 */
			temp8 = (u8) ROUND_UP_TO_32_bITS (temp8);

			structure_size = SIZEOF_RESOURCE (acpi_resource_address16) +
					   (temp8 * sizeof (u8));
			break;


		case RESOURCE_DESC_EXTENDED_XRUPT:
			/*
			 * Extended IRQ
			 */
			buffer = byte_stream_buffer;

			++buffer;
			MOVE_UNALIGNED16_TO_16 (&temp16, buffer);

			bytes_consumed = temp16 + 3;

			/*
			 * Point past the length field and the
			 * Interrupt vector flags to save off the
			 * Interrupt table length to the Temp8 variable.
			 */
			buffer += 3;
			temp8 = *buffer;

			/*
			 * To compensate for multiple interrupt numbers, add 4 bytes for
			 * each additional interrupts greater than 1
			 */
			additional_bytes = (u8) ((temp8 - 1) * 4);

			/*
			 * Resource Source Index and Resource Source are
			 * optional elements.  Check the length of the
			 * Bytestream.  If it is greater than 9, that
			 * means that an Index exists and is followed by
			 * a null termininated string.  Therefore, set
			 * the temp variable to the length minus the minimum
			 * byte stream length plus the byte for the Index to
			 * determine the size of the NULL terminiated string.
			 */
			if (9 + additional_bytes < temp16) {
				temp8 = (u8) (temp16 - (9 + additional_bytes));
			}

			else {
				temp8 = 0;
			}

			/*
			 * Ensure a 32-bit boundary for the structure
			 */
			temp8 = (u8) ROUND_UP_TO_32_bITS (temp8);

			structure_size = SIZEOF_RESOURCE (acpi_resource_ext_irq) +
					   (additional_bytes * sizeof (u8)) +
					   (temp8 * sizeof (u8));
			break;


		case RESOURCE_DESC_IRQ_FORMAT:
			/*
			 * IRQ Resource.
			 * Determine if it there are two or three trailing bytes
			 */
			buffer = byte_stream_buffer;
			temp8 = *buffer;

			if(temp8 & 0x01) {
				bytes_consumed = 4;
			}

			else {
				bytes_consumed = 3;
			}

			/*
			 * Point past the descriptor
			 */
			++buffer;

			/*
			 * Look at the number of bits set
			 */
			MOVE_UNALIGNED16_TO_16 (&temp16, buffer);

			for (index = 0; index < 16; index++) {
				if (temp16 & 0x1) {
					++number_of_interrupts;
				}

				temp16 >>= 1;
			}

			structure_size = SIZEOF_RESOURCE (acpi_resource_io) +
					   (number_of_interrupts * sizeof (u32));
			break;


		case RESOURCE_DESC_DMA_FORMAT:
			/*
			 * DMA Resource
			 */
			buffer = byte_stream_buffer;
			bytes_consumed = 3;

			/*
			 * Point past the descriptor
			 */
			++buffer;

			/*
			 * Look at the number of bits set
			 */
			temp8 = *buffer;

			for(index = 0; index < 8; index++) {
				if(temp8 & 0x1) {
					++number_of_channels;
				}

				temp8 >>= 1;
			}

			structure_size = SIZEOF_RESOURCE (acpi_resource_dma) +
					   (number_of_channels * sizeof (u32));
			break;


		case RESOURCE_DESC_START_DEPENDENT:
			/*
			 * Start Dependent Functions Resource
			 * Determine if it there are two or three trailing bytes
			 */
			buffer = byte_stream_buffer;
			temp8 = *buffer;

			if(temp8 & 0x01) {
				bytes_consumed = 2;
			}
			else {
				bytes_consumed = 1;
			}

			structure_size = SIZEOF_RESOURCE (acpi_resource_start_dpf);
			break;


		case RESOURCE_DESC_END_DEPENDENT:
			/*
			 * End Dependent Functions Resource
			 */
			bytes_consumed = 1;
			structure_size = ACPI_RESOURCE_LENGTH;
			break;


		case RESOURCE_DESC_IO_PORT:
			/*
			 * IO Port Resource
			 */
			bytes_consumed = 8;
			structure_size = SIZEOF_RESOURCE (acpi_resource_io);
			break;


		case RESOURCE_DESC_FIXED_IO_PORT:
			/*
			 * Fixed IO Port Resource
			 */
			bytes_consumed = 4;
			structure_size = SIZEOF_RESOURCE (acpi_resource_fixed_io);
			break;


		case RESOURCE_DESC_SMALL_VENDOR:
			/*
			 * Vendor Specific Resource
			 */
			buffer = byte_stream_buffer;

			temp8 = *buffer;
			temp8 = (u8) (temp8 & 0x7);
			bytes_consumed = temp8 + 1;

			/*
			 * Ensure a 32-bit boundary for the structure
			 */
			temp8 = (u8) ROUND_UP_TO_32_bITS (temp8);
			structure_size = SIZEOF_RESOURCE (acpi_resource_vendor) +
					   (temp8 * sizeof (u8));
			break;


		case RESOURCE_DESC_END_TAG:
			/*
			 * End Tag
			 */
			bytes_consumed = 2;
			structure_size = ACPI_RESOURCE_LENGTH;
			byte_stream_buffer_length = bytes_parsed;
			break;


		default:
			/*
			 * If we get here, everything is out of sync,
			 *  so exit with an error
			 */
			return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);
			break;
		}


		/*
		 * Update the return value and counter
		 */
		buffer_size += structure_size;
		bytes_parsed += bytes_consumed;

		/*
		 * Set the byte stream to point to the next resource
		 */
		byte_stream_buffer += bytes_consumed;
	}


	/*
	 * This is the data the caller needs
	 */
	*size_needed = buffer_size;
	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_rs_calculate_pci_routing_table_length
 *
 * PARAMETERS:  Package_object          - Pointer to the package object
 *              Buffer_size_needed      - u32 pointer of the size buffer
 *                                        needed to properly return the
 *                                        parsed data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Given a package representing a PCI routing table, this
 *              calculates the size of the corresponding linked list of
 *              descriptions.
 *
 ******************************************************************************/

acpi_status
acpi_rs_calculate_pci_routing_table_length (
	acpi_operand_object     *package_object,
	u32                     *buffer_size_needed)
{
	u32                     number_of_elements;
	u32                     temp_size_needed = 0;
	acpi_operand_object     **top_object_list;
	u32                     index;
	acpi_operand_object     *package_element;
	acpi_operand_object     **sub_object_list;
	u8                      name_found;
	u32                     table_index;


	FUNCTION_TRACE ("Rs_calculate_pci_routing_table_length");


	number_of_elements = package_object->package.count;

	/*
	 * Calculate the size of the return buffer.
	 * The base size is the number of elements * the sizes of the
	 * structures.  Additional space for the strings is added below.
	 * The minus one is to subtract the size of the u8 Source[1]
	 * member because it is added below.
	 *
	 * But each PRT_ENTRY structure has a pointer to a string and
	 * the size of that string must be found.
	 */
	top_object_list = package_object->package.elements;

	for (index = 0; index < number_of_elements; index++) {
		/*
		 * Dereference the sub-package
		 */
		package_element = *top_object_list;

		/*
		 * The Sub_object_list will now point to an array of the
		 * four IRQ elements: Address, Pin, Source and Source_index
		 */
		sub_object_list = package_element->package.elements;

		/*
		 * Scan the Irq_table_elements for the Source Name String
		 */
		name_found = FALSE;

		for (table_index = 0; table_index < 4 && !name_found; table_index++) {
			if ((ACPI_TYPE_STRING == (*sub_object_list)->common.type) ||
				((INTERNAL_TYPE_REFERENCE == (*sub_object_list)->common.type) &&
					((*sub_object_list)->reference.opcode == AML_INT_NAMEPATH_OP))) {
				name_found = TRUE;
			}

			else {
				/*
				 * Look at the next element
				 */
				sub_object_list++;
			}
		}

		temp_size_needed += (sizeof (pci_routing_table) - 4);

		/*
		 * Was a String type found?
		 */
		if (TRUE == name_found) {
			if (ACPI_TYPE_STRING == (*sub_object_list)->common.type) {
				/*
				 * The length String.Length field includes the
				 * terminating NULL
				 */
				temp_size_needed += (*sub_object_list)->string.length;
			}

			else {
				temp_size_needed += acpi_ns_get_pathname_length (
						   (*sub_object_list)->reference.node);
			}
		}

		else {
			/*
			 * If no name was found, then this is a NULL, which is
			 * translated as a u32 zero.
			 */
			temp_size_needed += sizeof (u32);
		}

		/* Round up the size since each element must be aligned */

		temp_size_needed = ROUND_UP_TO_64_bITS (temp_size_needed);

		/*
		 * Point to the next acpi_operand_object
		 */
		top_object_list++;
	}


	/*
	 * Adding an extra element to the end of the list, essentially a NULL terminator
	 */
	*buffer_size_needed = temp_size_needed + sizeof (pci_routing_table);
	return_ACPI_STATUS (AE_OK);
}