Abstract: A data processing apparatus is provided having a hierarchy of layers comprising at least two data processing layers, each data processing layer configured to receive data and to generate processed data for passing to a next lower layer in said hierarchy, according to a protocol specific to that data processing layer. Each data processing layer is configured intermittently to add synchronization information to its processed data, the synchronization information providing semantic information required to interpret the processed data. Each data processing layer is further configured to output its synchronization information in response to a synchronization request signal received from a lower layer in said hierarchy, and at least one data processing layer is configured, when outputting its synchronization information, to issue its synchronization request signal to a higher layer in the hierarchy.

Abstract: A graphics processing apparatus and method of performing graphics processing are provided. The graphics processing apparatus comprises a sequence of processing stages capable of performing graphics processing to generate a frame of display data. The graphics processing is performed on a tile-by-tile basis. The graphics processing apparatus is capable of determining if a current tile subject to the graphics processing is empty. At least one processing stage of the sequence of processing stages is omitted for graphics processing of the current tile in dependence on whether the current tile is empty.

Abstract: A data processing apparatus comprises processing circuitry arranged to process processing threads using resources accessible to the processing circuitry. A pipeline is provided for handling at least two pending threads awaiting processing by the processing circuitry. The pipeline includes at least one resource-requesting pipeline stage for requesting access to resources for the pending threads. A priority controller controls priority levels of the pending threads. The priority levels define a priority with which pending threads are granted access to resources. When a pending thread reaches a final pipeline stage, if the request resources are not yet available then the priority level of that thread is raised selectively and the thread is returned to a first pipeline stage of the pipeline. If the requested resources are available then the thread is forwarded from the pipeline.

Abstract: A graphics processing apparatus and method of performing graphics processing are provided. The graphics processing apparatus comprises a sequence of processing stages capable of performing graphics processing to generate a frame of display data. The graphics processing is performed on a tile-by-tile basis. The graphics processing apparatus is capable of determining if a current tile subject to the graphics processing is empty. At least one processing stage of the sequence of processing stages is omitted for graphics processing of the current tile in dependence on whether the current tile is empty.

Abstract: A data processing apparatus has processing circuitry for processing threads using resources accessible to the processing circuitry. Thread handling circuitry handles pending threads which are waiting for resources required for processing. When a request is made for a resource which is not available, a lock is set to ensure that once the resource becomes available, the resource remains available until the lock is removed. This prevents other threads reallocating the resource. When a subsequent pending thread requests access to the same locked unavailable resource, the lock is transferred to that subsequent thread so that the latest thread accessing that resource is considered the lock owning thread. The lock is removed once the lock owning thread is ready for processing.

Abstract: A data processing apparatus comprises processing circuitry arranged to process processing threads using resources accessible to the processing circuitry. A pipeline is provided for handling at least two pending threads awaiting processing by the processing circuitry. The pipeline includes at least one resource-requesting pipeline stage for requesting access to resources for the pending threads. A priority controller controls priority levels of the pending threads. The priority levels define a priority with which pending threads are granted access to resources. When a pending thread reaches a final pipeline stage, if the request resources are not yet available then the priority level of that thread is raised selectively and the thread is returned to a first pipeline stage of the pipeline. If the requested resources are available then the thread is forwarded from the pipeline.

Abstract: A data processing apparatus comprises processing circuitry arranged to process processing threads using resources accessible to the processing circuitry. A pipeline is provided for handling at least two pending threads awaiting processing by the processing circuitry. The pipeline includes at least one resource-requesting pipeline stage for requesting access to resources for the pending threads. A priority controller controls priority levels of the pending threads. The priority levels define a priority with which pending threads are granted access to resources. When a pending thread reaches a final pipeline stage, if the request resources are not yet available then the priority level of that thread is raised selectively and the thread is returned to a first pipeline stage of the pipeline. If the requested resources are available then the thread is forwarded from the pipeline.

Abstract: A data processing apparatus has processing circuitry for processing threads using resources accessible to the processing circuitry. Thread handling circuitry handles pending threads which are waiting for resources required for processing. When a request is made for a resource which is not available, a lock is set to ensure that once the resource becomes available, the resource remains available until the lock is removed. This prevents other threads reallocating the resource. When a subsequent pending thread requests access to the same locked unavailable resource, the lock is transferred to that subsequent thread so that the latest thread accessing that resource is considered the lock owning thread. The lock is removed once the lock owning thread is ready for processing.

Abstract: A data processing apparatus comprises processing circuitry arranged to process processing threads using resources accessible to the processing circuitry. A pipeline is provided for handling at least two pending threads awaiting processing by the processing circuitry. The pipeline includes at least one resource-requesting pipeline stage for requesting access to resources for the pending threads. A priority controller controls priority levels of the pending threads. The priority levels define a priority with which pending threads are granted access to resources. When a pending thread reaches a final pipeline stage, if the request resources are not yet available then the priority level of that thread is raised selectively and the thread is returned to a first pipeline stage of the pipeline. If the requested resources are available then the thread is forwarded from the pipeline.

Abstract: A data processing apparatus is provided having a hierarchy of layers comprising at least two data processing layers, each data processing layer configured to receive data and to generate processed data for passing to a next lower layer in said hierarchy, according to a protocol specific to that data processing layer. Each data processing layer is configured intermittently to add synchronization information to its processed data, the synchronization information providing semantic information required to interpret the processed data. Each data processing layer is further configured to output its synchronization information in response to a synchronization request signal received from a lower layer in said hierarchy, and at least one data processing layer is configured, when outputting its synchronization information, to issue its synchronization request signal to a higher layer in the hierarchy.