Abstract: Firmware determines during a boot of a computer, if a bus enumeration is needed or if the computer can be booted quicker by skipping a bus enumeration. The firmware performs a bus enumeration if this a first boot or if the bus has had it infrastructure changed since the previous boot. For buses that have only fixed resources coupled to it, then the bus configuration cannot change. Also, for buses that do not have only fixed resources, the infrastructure may be probed to determine if the bus configuration has changed. If there is no change, bus enumeration is not needed. Metadata is created, updated and stored in flash memory involving the bus infrastructure. Since the metadata is stored, a bus enumeration is not needed to gather information about the bus when no change has occurred.

Abstract: A database engine is executed within an Extensible Firmware Interface (“EFI”) environment that provides generic database functions on records having arbitrary data types. Database functions such as adding, deleting, and searching records may be performed by the database engine. The database engine utilizes a database structure for organizing the database that includes an initial count field for storing the initial number of records to be stored in the database, a record count field for storing the current number of records in the database, a key count field for storing the number of key fields in a stored data record, a key field for storing a pointer to a function for retrieving the value of a key field, and an index array field for storing a pointer to an index array. The index array is a sorted array of pointers to each of the data records in the database.

Abstract: Memory address resources requests are collected from devices on a bus. The requests are then sorted into descending order. For each resource request, a determination is then made as to whether the request is for a device that is behind a bridge. If the request is not for a device behind a bridge, the request is allocated. The request is also allocated if the request is for a device behind a bridge device and the request can be allocated without allocating padding. If a request is for a device behind a bridge and the request cannot be satisfied without using padding, then sufficient padding is allocated to properly align the request. An amount of padding may be allocated that satisfies the alignment requirement of the next resource request to be allocated. Requests for devices on the primary interface of the bridge device may also be satisfied from within the padding.

Abstract: Technologies are provided herein for multiple platform support in a computer system firmware. A firmware is built for each hardware platform to be supported. At built time of the firmware for each platform to be supported, an instance of platform specific information is extracted from the built firmware and stored. Once the platform specific information instances have been collected for each platform to be supported, the platform specific information instances are stored in a multi-platform firmware. At run-time of the multi-platform firmware, the particular hardware platform that the multi-platform firmware is executing upon is identified. Once the platform has been identified, the particular instance of platform specific information corresponding to the identified platform is selected. The selected instance of platform specific information is then loaded and exposed for consumption by other programs.

Abstract: A non-volatile memory device stores configuration variables for use by a computer firmware. The variable is initially stored in the memory device in a manner that minimizes the number of bits used to store the variable that are in the updated state. When a request is received to change the initial value of the variable to an updated value, the value is changed in place by changing only the bits used to store the variable from an erased state to an updated state, by only setting the invert flag, by setting the invert flag and by changing one or more of the bits of the variable from the erased state to the updated state, or by storing the updated value of the variable in a new location in the memory device.

Abstract: Methods, systems, and computer-readable media are provided for providing generic database services within an EFI environment. A database engine is executed within an EFI environment that provides generic database functions on records having arbitrary data types. Database functions such as adding, deleting, and searching records may be performed by the database engine. The database engine utilizes a database structure for organizing the database that includes an initial count field for storing the initial number of records to be stored in the database, a record count field for storing the current number of records in the database, a key count field for storing the number of key fields in a stored data record, a key field for storing a pointer to a function for retrieving the value of a key field, and an index array field for storing a pointer to an index array. The index array is a sorted array of pointers to each of the data records in the database.

Abstract: An improved HII database driver is provided in an EFI environment. The HII database driver is capable of storing extended information regarding an HII component in an HII database at the time the package containing the HII component is parsed for inclusion in the HII database. Extended information for a string may include length of the string in Unicode characters or the length of the string in narrow screen glyphs. The HII database driver also exposes methods through which the extended information may be retrieved from the HII database. The extended information may be utilized to allocate an appropriately sized buffer for storing the string.

Abstract: An improved HII database driver is provided in an EFI environment. The HII database driver is capable of storing extended information regarding an HII component in an HII database at the time the package containing the HII component is parsed for inclusion in the HII database. Extended information for a string may include length of the string in Unicode characters or the length of the string in narrow screen glyphs. The HII database driver also exposes methods through which the extended information may be retrieved from the HII database. The extended information may be utilized to allocate an appropriately sized buffer for storing the string.

Abstract: A firmware memory manager allocates memory for code and data based on a lifespan associated with each allocation. The memory manager determines whether each allocated block of memory is needed only for a certain lifespan. Based on this determination, blocks of memory needed beyond the certain lifespan are all allocated adjacent to each other in memory. Once execution exceeds the certain lifespan, memory needed only for boot time is reported as being available for reuse by an operating system.

Abstract: Methods and computer systems provide for the selection of a DSDT that accurately describes a current configuration of the computer system. Because the system configuration can change over time, such as due to hardware malfunctions or the addition or removal of hardware requiring a BIOS interface to software, multiple DSDTs are available for selection so that for each computer system configuration, an appropriate DSDT is available. Upon boot-up, the hardware of the computer system is analyzed to determine the set of available North Bridge chipset devices. An appropriate DSDT is then selected from a set of multiple DSDTs for the current computer system configuration.

Abstract: Methods, computer systems, and computer readable media maintain address values of a module stored in computer memory by changing the module pointer values upon switches between physical memory addressing and virtual memory addressing. Upon a function call to the module, the pointer values of the module are changed to correspond to the current mode of memory addressing. Thus, upon changing the pointer values to the current mode, the locations of the module can be properly accessed during execution of the module in the computer system.

Abstract: Each attention button is tied to a presence signal, which is also used to detect the presence of a PCI adapter card within a slot. By comparing HPPC register states, pending due to a system control interrupt (“SCI”), with stored HPPC register states prior to the SCI, the HPPC is able to distinguish between an attention button press and a PCI card insertion or removal and therefore may respond appropriately to the SCI. According to the method, SCIs generated in a computer system by attention buttons are diagnosed and serviced by storing the contents of the HPPC registers. The contents of the registers identify the state of the presence and manually-operated retention latch (“MRL”) signals prior to the occurrence of a SCI and upon receiving a SCI corresponding to a state change for either signal, identify the hot plug controller and the slot where the interrupt occurred.

Abstract: Methods and computer systems provide for the selection of a DSDT that accurately describes a current configuration of the computer system. Because the system configuration can change over time, such as due to hardware malfunctions or the addition or removal of hardware requiring a BIOS interface to software, multiple DSDTs are available for selection so that for each computer system configuration, an appropriate DSDT is available. Upon boot-up, the hardware of the computer system is analyzed to determine the set of available North Bridge chipset devices. An appropriate DSDT is then selected from a set of multiple DSDTs for the current computer system configuration.

Abstract: Methods and computer systems provide updating of device configuration information in a DSDT of a BIOS for a computer system. Because the device configuration information can be changed, this information is determined upon boot-up of the computer system. The determined device configuration information such as the device number, function number, and/or bus number is then updated in the DSDT table at an appropriate entry for the device rather than having the device configuration information be pre-defined when the DSDT is developed.

Abstract: Each attention button is tied to a presence signal, which is also used to detect the presence of a PCI adapter card within a slot. By comparing HPPC register states, pending due to a system control interrupt (“SCI”), with stored HPPC register states prior to the SCI, the HPPC is able to distinguish between an attention button press and a PCI card insertion or removal and therefore may respond appropriately to the SCI. According to the method, SCIs generated in a computer system by attention buttons are diagnosed and serviced by storing the contents of the HPPC registers. The contents of the registers identify the state of the presence and manually-operated retention latch (“MRL”) signals prior to the occurrence of a SCI and upon receiving a SCI corresponding to a state change for either signal, identify the hot plug controller and the slot where the interrupt occurred.

Abstract: Methods and computer systems provide updating of device configuration information in a DSDT of a BIOS for a computer system. Because the device configuration information can be changed, this information is determined upon boot-up of the computer system. The determined device configuration information such as the device number, function number, and/or bus number is then updated in the DSDT table at an appropriate entry for the device rather than having the device configuration information be pre-defined when the DSDT is developed.

Abstract: Methods and computer systems provide for the selection of a DSDT that accurately describes a current configuration of the computer system. Because the system configuration can change over time, such as due to hardware malfunctions or the addition or removal of hardware requiring a BIOS interface to software, multiple DSDTs are available for selection so that for each computer system configuration, an appropriate DSDT is available. Upon boot-up, the hardware of the computer system is analyzed to determine the set of available North Bridge chipset devices. An appropriate DSDT is then selected from a set of multiple DSDTs for the current computer system configuration.