Abstract: Typical hybrid graphics systems operate in either a “high-performance mode” or in an “energy saver mode.” While operating in the high-performance mode, a discrete graphics processing unit (dGPU) performs high-performance graphics processing operations and also receives and satisfies access requests targeting a configuration space within the dGPU. While operating in the energy saver mode, an integrated graphics processing unit (iGPU) performs graphics processing operations and the dGPU is powered down. In this scenario, a system management unit (SMU) intercepts and satisfies access requests targeting the dGPU. Since access requests targeting the dGPU are satisfied while the dGPU is powered down, the dGPU continues to be enumerated in the system using the same system resources as originally granted, and can therefore be switched to for implementing high-performance mode more quickly than if it was removed, and required a complete plug-and-play re-enumeration and re-allocation of system resources.

Abstract: A security command protocol provides secure authenticated access to an auxiliary security memory within a SCSI storage device. The auxiliary security memory acts as an authenticated separate secure storage area that stores sensitive data separately from the user data area of the SCSI storage device. The security command protocol is used to access the auxiliary security memory. The security command protocol allows a trusted execution environment to transport sensitive data to and from storage in the auxiliary security memory. The regular execution environment does not have access to the security command protocol or the auxiliary security memory. The security command protocol and auxiliary security memory eliminate the need for additional secure storage components in devices that provide the security features of firmware TPM.

Abstract: One embodiment of the present invention sets forth a technique for automatically provisioning a diskless computing device and an associated server system. A diskless computing device client incorporates an iSCSI initiator that is used to access resources provided by an iSCSI target that is resident on a server computing device. The iSCSI initiator is implemented in the client firmware, providing INT13 disk services entry points, thereby enabling the client to transparently access virtual storage devices at boot time. The client device conducts an apparently local installation using the virtual storage devices provided by the server computing device. A short signature value is associated with the boot image, uniquely associating the boot image with the specific client hardware configuration. When the client device boots normally, the signature value of the client device is presented to the server computing device to automatically reference the appropriate boot image.

Abstract: A software or hardware agent running on a personal computing (PC) device provides allows a consumer electronic device connected to the PC device over a high definition multimedia interface (HDMI) network to control the PC device using standardized commands. This enables a user to control the PC device and other consumer electronic devices that are connected to the HDMI network using a single interface. The agent responds as a consumer electronic device and translates the standardized commands as universal serial bus (USB) human interface device (HID) input reports to the PC device operating system. The agent represents the specific capabilities of the PC device as standard consumer electronic device controls.

Abstract: One embodiment of the present invention sets forth a technique for automatically provisioning a diskless computing device and an associated server system. A diskless computing device client incorporates an iSCSI initiator that is used to access resources provided by an iSCSI target that is resident on a server computing device. The iSCSI initiator is implemented in the client firmware, providing INT13 disk services entry points, thereby enabling the client to transparently access virtual storage devices at boot time. The client device conducts an apparently local installation using the virtual storage devices provided by the server computing device. A short signature value is associated with the boot image, uniquely associating the boot image with the specific client hardware configuration. When the client device boots normally, the signature value of the client device is presented to the server computing device to automatically reference the appropriate boot image.

Abstract: One embodiment of the present invention sets forth a technique for synchronization between two or more processors. The technique implements a spinlock acquire function and a spinlock release function. A processor executing the spinlock acquire function advantageously operates in a low power state while waiting for an opportunity to acquire spinlock. The spinlock acquire function configures a memory monitor to wake up the processor when spinlock is released by a different processor. The spinlock release function releases spinlock by clearing a lock variable and may clear a wait variable.

Abstract: One embodiment of the present invention sets forth a technique for performing RAID-6 computations using simple arithmetic functions and two-dimensional table lookup operations. A set of threads within a multi-threaded processor are assigned to perform RAID-6 computations in parallel on a stripe of RAID-6 data. A set of lookup tables are stored within the multi-threaded processor for access by the threads in performing the RAID-6 computations. During normal operation of a related RAID-6 disk array, RAID-6 computations may be performed by the threads using a small set of simple arithmetic operations and a set of lookup operations to the lookup tables. Greater computational efficiency is gained by reducing the RAID-6 computations to simple operations that are performed efficiently on a multi-threaded processor, such as a graphics processing unit.

Abstract: A software or hardware agent running on a personal computing device provides allows application programs to interact with consumer electronic devices using standardized controls. The consumer electronic devices appear to be directly connected to the personal computing device rather than being connected over a high definition multimedia interface (HDMI) network. This enables a user to control the consumer electronic devices using a single interface rather than a separate interface for each consumer electronic device. The agent enumerates a universal serial bus (USB) human interface device (HID) for each consumer electronic device reported on the HDMI network. The USB HIDs represent the specific capabilities of the each one of the consumer electronic devices.

Abstract: Systems and methods for performing native command queuing according to the protocol specified by Serial ATA II for transferring data between a disk and system memory are described. Native command queuing context for queued commands is maintained by a host controller device driver and is provided to the host controller as needed to process the queued commands. The host controller is simplified since it only stores the context of the one command being processed. The host controller generates a backoff interrupt when a command cannot be queued. The host controller generates a DMA transfer context request interrupt to request programming of the registers that store the context for the one command being processed.

Abstract: Systems and methods for accessing host bus adapter (HBA) management features for Small Computer System Interface (SCSI) based HBAs produced by different vendors use a standard interface. A virtual SCSI target is created to emulate each HBA in a system, representing the HBA as a logical unit. Standard commands specified for logical units are used by an HBA device driver to perform HBA management operations. The standard commands may be used to access HBA management features for any HBA regardless of the vendor. Therefore, the HBA communication interface is standardized for HBA devices, permitting efficient access regardless of the operating system or HBA vendor.

Abstract: One embodiment of the present invention sets forth a technique for performing RAID-6 computations using simple arithmetic functions and two-dimensional table lookup operations. Four lookup tables are computed and saved prior to normal operation of a RAID-6 disk array. During normal operation of the RAID-6 disk array, all RAID-6 related computations may be performed using a small set of simple arithmetic operations and a set of lookup operations to three of the four previously saved lookup tables. Greater computational efficiency is gained by reducing the RAID-6 computations to simple operations that are performed efficiently on a typical central processing unit or graphics processing unit.

Abstract: Embodiments of the invention provide a method for selecting a network boot device using a hardware class identifier. Generally, embodiments of the invention enable a diskless client to communicate a hardware class identifier in a network connection request. The hardware class identifier is used to determine the proper boot server to provide a boot image to the diskless client.

Abstract: Embodiments of the present invention provide a method for handling errors in data servers. Generally, embodiments of the invention enable a data packet that is marked as erroneous to be handled so that it is not committed to permanent storage. One or more components are configured to recognize a poisoned data indicator, and to respond to the indicator by taking programmed actions to delete the data, to stop the data from being transmitted, to notify upstream components, and to purge related data from downstream components.

Abstract: One embodiment of the present invention sets forth a technique for reducing the latency associated with media protection notification for serial interface mass storage devices, such as serial AT attachment (SATA) hard disk drives. A new link layer primitive, referred to as hold-emergency (HOLDE), incorporates the flow-control behavior of the existing HOLD command, with the additional new action of notifying the hard disk drive to take emergency steps to prepare for impact. The HOLDE link layer primitive operates in conjunction with the existing hold-acknowledge (HOLDA) primitive and is semantically similar to the existing HOLD primitive. The HOLDE mechanism is preferably implemented directly in hardware in the SATA link layer state machines within the host and the hard disk drive.

Abstract: Systems and methods for performing data transfer rate throttling o improve the effective data transfer rate for SATA storage devices. The data transfer rate is diluted by inserting ALIGN primitives when data is sent. The receiving device simply discards the ALIGN primitives. Therefore, the receive data FIFO does not fill as quickly and fewer flow control sequences are needed for flow control to prevent the receive data FIFO from overflowing. An advantage of using the ALIGN primitives instead of conventional flow control is that the round-trip handshake latency is not incurred to disable and later enable data transfers.

Abstract: One embodiment of the present invention sets forth a technique for reducing the latency associated with media protection notification for serial interface mass storage devices, such as serial AT attachment (SATA) hard disk drives. A new link layer primitive, referred to as hold-emergency (HOLDE), incorporates the flow-control behavior of the existing HOLD command, with the additional new action of notifying the hard disk drive to take emergency steps to prepare for impact. The HOLDE link layer primitive operates in conjunction with the existing hold-acknowledge (HOLDA) primitive and is semantically similar to the existing HOLD primitive. The HOLDE mechanism is preferably implemented directly in hardware in the SATA link layer state machines within the host and the hard disk drive.

Abstract: One embodiment of the present invention sets forth a technique for mapping a small computer system interface (SCSI) architecture model-3 (SAM-3) task priority to an IEEE Standard 802.1q tag control information (TCI) field. Four bits that define a SAM-3 task priority are mapped to the three user priority bits within a standard 802.1q TCI field. By enabling the SAM-3 task priority of a given SCSI command to determine the user priority within a related IEEE 802.1q Ethernet frame, the Ethernet network is enabled to substantially honor the requested task priority for the SCSI command.

Abstract: One embodiment of the present invention sets forth a technique for establishing high user priority for Ethernet frames related to demand-paging operations over iSCSI. The iSCSI initiator is configured to identify demand-page operations using techniques specific to the operating system and to set the 802.1q tag control information (TCI) user priority bit field to reflect high priority for demand-page related Ethernet frames. The demand-page related Ethernet frames are then delivered to the iSCSI target with a higher priority through the intervening Ethernet network than other traffic. Overall performance of demand paging operations is improved relative to prior art systems through an average reduction in network latency.

Abstract: Systems and methods for performing native command queuing according to the protocol specified by Serial ATA II for transferring data between a disk and system memory are described. Native command queuing context for queued commands is maintained by a host controller device driver and is provided to the host controller as needed to process the queued commands. The host controller is simplified since it only stores the context of the one command being processed. The host controller generates a backoff interrupt when a command cannot be queued. The host controller generates a DMA transfer context request interrupt to request programming of the registers that store the context for the one command being processed.

Abstract: One embodiment of the present invention sets forth a technique for concisely identifying the hardware configuration of a computer system through a single signature value. This signature value is computed by passing specific hardware configuration information through a hashing function. The hardware configuration information may include, among other things, selected elements of the SMBIOS system description as well as PCI topology and PCI bus type information.