Prefetching page access data for input surfaces requiring processing

A data processing system comprising:

• a main memory;
• one or more processing units operable to generate input surfaces each comprising an image for display and to store the input surfaces in the main memory;
• and
• a processing unit;
• wherein the processing unit comprises:
• a memory read sub-system operable to read data of one or more input surfaces to be processed by the processing unit, wherein each input surface comprises an image for display;
• a processing stage operable to process the one or more read input surfaces each comprising an image for display to generate an output surface, based on control information provided to the processing unit;
• and
• an output stage operable to provide the output surface;
• wherein the memory read sub-system is operable to:
• take as an input the control information provided to the processing unit to control the processing by the processing stage of the one or more input surfaces each comprising an image for display to generate the output surface;
• use the control information to determine information relating to the data for the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface, to determine one or more memory pages storing the data relating to the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface;
• and
• request in advance the loading of memory page access data for the determined memory pages storing data relating to the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface into a memory page access data cache.

A method of operating a processing unit for a data processing system, the processing unit comprising:

• a memory read sub-system operable to read data of one or more input surfaces to be processed by the processing unit, wherein each input surface comprises an image for display;
• a processing stage operable to process the one or more read input surfaces each comprising an image for display to generate an output surface, based on control information provided to the processing unit;
• and
• an output stage operable to provide the output surface;
• the method comprising, when the processing unit is to generate the output surface from the one or more input surfaces each comprising an image for display based on the control information provided to the processing unit:
• the memory read sub-system:
• taking as an input the control information provided to the processing unit to control the processing by the processing stage of the one or more input surfaces each comprising an image for display to generate the output surface;
• using the control information to determine information relating to the data for the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface, to determine one or more memory pages storing the data relating to the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface;
• and
• requesting the loading of memory page access data for the determined memory pages storing data relating to the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface into a memory page access data cache in advance of a request for the data of the one or more input surfaces each comprising an image for display that is stored in the memory pages in question.

A non-transitory computer-readable storage medium storing computer software code which when executing on a processor performs a method of operating a processing unit for a data processing system, the processing unit comprising:

• a memory read sub-system operable to read data of one or more input surfaces to be processed by the processing unit, wherein each input surface comprises an image for display;
• a processing stage operable to process the one or more read input surfaces each comprising an image for display to generate an output surface, based on control information provided to the processing unit;
• and
• an output stage operable to provide the output surface;
• the method comprising, when the processing unit is to generate the output surface from the one or more input surfaces each comprising an image for display based on the control information provided to the processing unit:
• the memory read sub-system:
• taking as an input the control information provided to the processing unit to control the processing by the processing stage of the one or more input surfaces each comprising an image for display to generate the output surface;
• using the control information to determine information relating to the data for the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface, to determine one or more memory pages storing the data relating to the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface;
• and
• requesting the loading of memory page access data for the determined memory pages storing data relating to the one or more input surfaces each comprising an image for display that will be required by the processing stage to generate the output surface into a memory page access data cache in advance of a request for the data of the one or more input surfaces each comprising an image for display that is stored in the memory pages in question.