Apple Inc.

Sun Microsystems, Inc.

David J Redman

Adrian T Sheppard

Ian C Hendry

Thomas W Costa

Eve Brasfield

Michael F Culbert

Kenneth Christian Dyke

Tim Millet

Sreeraman Anantharaman

Simon M Douglas

William O Ferry

Changki Min

Unmesh Sahasrabuddhe

Amanda R Rainer

David A Leech

Mike Nugent

Ingrid Aligaen

Chris Niederauer

Paolo Sacchetto

Ashley N Saulsbury

Geoffrey Grant Stahl

John Johnson

Gregory Charles Onufer

Geoff Stahl

James A Mott

Wai Yu Trevor Tsang

Phillip J Churchill

Philip J Churchill

Colin Witby-Strevens

Ashish Munjal

Nancy Lee

Alexander Naidich

Arvind Kini

Chengchung Chen

Systems and methods are disclosed to enable switching of graphics processing unit (GPU) resources based on different factors. Embodiments include a virtual graphics driver as an interface between GPU drivers and the applications or graphics framework executing on an electronic device. The virtual graphics driver may switch GPU resources from a first GPU to a second GPU by routing function calls to the first GPU or the second GPU. The switching of GPU resources may be based on power management, system events such as hot-plug events, load management, user requests, any other factor, or any combination thereof. In some embodiments, a virtual frame buffer driver is provided that interfaces with the frame buffer of the GPU and provides a virtual view of the frame buffer to manage additional system application programming interfaces (APIs) during the switch.

Virtual graphics device driver

Information is provided to a source device during link training regarding the state of a remote link when an intermediate device using a different protocol is connected between source and sink devices. The intermediate device includes two controllers connected by a cable, the first controller being connected to the source device and the second controller being connected to the sink device. State information regarding the remote device may be provided by a state machine that stores data to a register on the intermediate device. Based on the state of the remote link, the source device is able to generate a representation of the end to end link between the source and sink device, and to perform link training accordingly.

Synchronous link training

Display control of a sink device is provided. The sink device has tiles forming a display and is connected to a source device via interfaces. Each interface provides a video stream to a respective tile. The source device includes a policy engine, and a GPU (graphics processing unit). The policy engine obtains link training data provided by the driver of the GPU, including information regarding a negotiated link configuration for the interfaces. The policy engine generates configuration data based on the synchronous link training data, the configuration data including a set of configurations each of which associated with a resolution of the display. The policy engine provides driving data to the GPU derived by mapping a resolution to a configuration implementation on the interfaces based on the synchronous link training data and the configuration data.

Display scaling

An electronic device selectively couples a head with links in a graphics processing unit to a currently selected display port in a pair of display ports. During operation, control logic in the electronic device monitors a pair of configuration signals from the pair of display ports, where the pair of configuration signals correspond to physical connections to the pair of display ports. Then, the control logic determines a selection control signal based on the monitored pair of configuration signals, a policy setting and a default display port, where the selection control signal specifies the currently selected display port. Moreover, the control logic provides the selection control signal to a multiplexer in the electronic device. Next, the multiplexer selectively couples the head with the links in the graphics processing unit to the currently selected display port based on the selection control signal.

Sharing a graphics-processing-unit display port

The disclosed embodiments provide a system that facilitates seamlessly switching between graphics-processing units (GPUs) to drive a display. In one embodiment, the system receives a request to switch from using a first GPU to using a second GPU to drive the display. In response to this request, the system uses a kernel thread which operates in the background to configure the second GPU to prepare the second GPU to drive the display. While the kernel thread is configuring the second GPU, the system continues to drive the display with the first GPU and a user thread continues to execute a window manager which performs operations associated with servicing user requests. When configuration of the second GPU is complete, the system switches the signal source for the display from the first GPU to the second GPU.

Facilitating efficient switching between graphics-processing units

A system may include a graphics controller and a display. The graphics controller may generate video data to display on the display. The display may include a display panel for displaying the video data, a backlight unit for providing the display panel with backlight, and a display timing controller for communicating with the graphics controller over a communications path. The communications path may include a video data path for conveying video data bits, an interrupt path for conveying interrupts, and a sideband control path for conveying control signals such as a backlight enable signal for the backlight unit. The graphics controller and timing controller may perform link training operations to assess link quality between the graphics controller and timing controller. The timing controller may use interrupts to inform the graphics controller of system status. Use of the interrupts may help the system minimize the time consumed during display power-up operations.

Display systems with handshaking for rapid backlight activation

Systems and methods include an electronic device having multiple GPUs and a GPU power control process that controls switching between a first GPU and a second GPU, such as a high performance GPU. The electronic device may be coupled to an external display by a passive adapter or an active adapter. The GPU power control process may determine if the second GPU is active and switch to the second GPU upon connection of the external display through either the passive adapter or the active adapter. Upon connection of an active adapter, the GPU power control process may use hot plug functionality to determine connection of the external display to the active adapter and provide appropriate switching in response thereto.

Systems and methods for hot plug GPU power control

Exemplary embodiments of methods, apparatuses, and systems for seamlessly migrating a user visible display stream sent to a display device from one rendered display stream to another rendered display stream are described. For one embodiment, mirror video display streams are received from both a first graphics processing unit (GPU) and a second GPU, and the video display stream sent to a display device is switched from the video display stream from the first GPU to the video display stream from the second GPU, wherein the switching occurs during a blanking interval for the first GPU that overlaps with a blanking interval for the second GPU.

Seamless display migration

A method and apparatus for delivering a device driver to an operating system without user intervention. One or more operating systems (e.g., different operating system programs, different versions of one operating system) execute on a computer platform. During booting of an operating system a device is identified for which a driver is needed. The driver is requested from a service processor of the platform, which includes memory or storage for storing multiple device drivers (or multiple versions of one driver, for different operating systems). The driver is retrieved from the service processor's storage and delivered to the operating system.

Method and apparatus for delivering device drivers

A system and method for providing hot swap capability with minimal changes in a system which uses existing circuitry and drivers. In one embodiment, a computer system has a host processor and a hot-swap-capable device, each coupled to a Compact PCI bus. The device includes one or more pre-existing circuits (ASICs and/or standard off-the-shelf circuits) and corresponding pre-existing drivers. A hot-swap-capable bus bridge is interposed between the circuits and the Compact PCI bus to provide hot swap functionality while allowing the pre-existing circuits and drivers to be used without modification. In one embodiment, an Intel 21554 is used as the hot-swap-capable bus bridge. The 21554 is programmed to emulate a transparent bridge. Modified drivers in the OBP firmware and OS software allow the system to recognize the 21554 in this transparent configuration and to probe the secondary side of the 21554 for the circuits.

System and method for providing hot swap capability using existing circuits and drivers with minimal changes

Growing community of inventors

Fremont, CA, United States of America

David J Redman