Abstract: A method and a system for stalling large pipelined designs. A computational pipeline may comprise a first module and a second module coupled together. The first module may propagate one or more signals to the second module. A stall-signal may be asserted in order to stall the computational pipeline if the second module is not ready to receive the one or more signals from the first module. The one or more signals propagated from the first module and the asserted stall-signal may be buffered in a stall-buffer. The asserted stall-signal may be propagated to the first module in a next cycle. The first module may be stalled in response to the first module receiving the propagated asserted stall-signal. Next, the asserted stall-signal may be propagated up the computational pipeline.

Abstract: A reconfigurable system for performing a set of arithmetic operations. The reconfigurable system may have a frame buffer, an accumulation buffer and a pixel computation unit. The pixel computation unit includes a control unit and one or more copies of a reconfigurable circuit. The reconfigurable circuit may include a subtractor, a multiplier, an adder, and a set of multiplexors. The control logic drives selects lines of the set of multiplexors in the one or more circuit copies through one or more computational cycles in order to implement a programmable operation (such as scale and/or bias, accumulate, dynamic blend and matrix multiply). The pixel computation unit may receive pixels values from one or more sources including the frame buffer and the texture buffer, and operate on the pixels using the one or more circuit copies to generate a stream of output pixels.

Abstract: A system and method for preserving the order of data items through a divergence-and-reconvergence of two or more paths in a hardware device. A host processor may write a first token to a first path in the hardware device. A convergence unit in the hardware device may receive and store the first token in a synchronization register. The host processor may poll the synchronization register to determine when the first token arrives in the synchronization register. In response to determining that the first token has arrived in the synchronization register, the host processor may safely write a sequence of one or more data items to a second path in the hardware device.

Abstract: A system and a method for improving magnified texture-mapped pixel performance in a single-pixel pipeline. A plurality of textured pixel addresses corresponding to a plurality of pixels may be generated. A FIFO or other memory unit may be used to linearly order the plurality of textured pixel addresses. Two consecutive textured pixel addresses out of the plurality of textured pixel addresses may be examined if they map to a common set of texels in texture space. The two consecutive textured pixel addresses may be merged together and propagated down the pipeline if they map to the common set of texels. However, only a first of the two consecutive textured pixel addresses may be propagated down the pipeline if the two consecutive textured pixel addresses do not map to a common set of texels. Texel data may be generated in response to receiving either the combined texel structure or the first of the two textured pixel addresses.

Abstract: An integrated circuit including logic for testing internal operation of the integrated circuit. The integrated circuit may comprise a plurality of internal functional blocks coupled by a plurality of internal buses. The integrated circuit may also comprise a set of test control input pins and a set of test output pins comprised on the integrated circuit. The integrated circuit may comprise selection logic. The selection logic comprises inputs coupled to various ones of the internal buses, an output coupled to the set of test output pins, and a select input coupled to receive select signals from the set of test control input pins. The selection logic is operable to select internal bus signals from an internal bus based on the select signals from the test control input pins, and the selection logic is configured to output the selected internal bus signals to the set of test output pins.

Abstract: A system for dynamic blending of an image into an accumulation buffer. The blending system may include an accumulation buffer, an image buffer, and a mixing unit. The mixing unit may be configured to read a stream of image pixels from the image buffer, to read a stream of corresponding pixels from the accumulation buffer, to blend each image pixel with the corresponding accumulation buffer pixel based on an alpha value provided with the image pixel, and thus, generate a stream of output pixels. The stream of output pixels may be returned to the accumulation buffer. The color depth precision of the accumulation buffer may be larger than the color depth precision of the image buffer.

Abstract: A method and system for synchronizing data streams and transferring control of resources between two processes in a graphics processor is described. The method allows for completion of pending operations of a first process in a manner that ensures the first process may be restarted without loss of data or process sequence. The processing pipeline is allowed to complete normal execution of all process operations required to reach a first process step that may be interrupted. The second process is initiated when the interruption of the first process is verified. Upon completion of the second process, the first process is reactivated at the next process step in sequence.

Abstract: A programmable filter comprising a tree of computational units, where each computational unit is configured to receive multiple inputs and generate multiple outputs, where the tree receives a set of input operands and generates output operands, where, in a sum of products mode, the output operands of the tree comprise a sum of products of the input operands by corresonding N-bit coefficients, where N is a positive integer, where, in a linear interpolation mode, each of the output operands of the tree comprise linear interpolations of at least two of the input operands, wherein coefficients of the linear interpolations have (N/2) bits of precision.

Abstract: A system and method for reading register contents from a computational pipeline having a plurality of computational units. The system includes a readback bus and a read control unit. The readback bus has a plurality of logic units coupled in a series. Each logic unit couples to a corresponding one of the computational units. The read control unit couples to each of the computational units through a corresponding load line, and is configured to assert a load signal on one of the load lines in response to a register read request. Each of the computational units is configured to transmit a data value from a selected register onto the readback bus in response to detecting an assertion of the load signal on its corresponding load line.

Abstract: An optimizing unit for use with an interleaved memory and suitable for use in a computer graphics system is described. The unit utilizes knowledge of the repetitive and predictable nature of texture buffer accesses to potentially reduce the number of memory fetches. The unit maintains a queue of pending requests for tiles of data from the memory, and predicts the retrieval of redundant data within short sequences of requests. The redundant data is retrieved from the memory once, and repeated as necessary from local temporary storage registers.

Abstract: A predictive optimizing unit for use with an interleaved memory and suitable for use in a computer graphics system is described. The unit maintains a queue of pending requests for data from the memory, and prioritizes precharging and activating interleaves with pending requests. Interleaves which are in a ready state may be accessed independently of the precharging and activation of non-ready interleaves.

Abstract: A graphics system configured to apply multiple layers of texture information to primitives. The graphics system receives parameters defining a primitive and performs a size test on the primitive. If the size test cannot guarantee that a fragment size of the primitive is less than or equal to a fragment capacity of a texture accumulation buffer, the primitive is divided into subprimitives, and the graphics system applies the multiple layers of texture to fragments which intersect the primitive. The graphics system switches from a current layer to the layer next when it has applied textures corresponding to the current layer to all the fragments intersecting the primitive. The graphics system stores color values associated with the primitive fragments in the texture accumulation buffer between the application of successive texture layers.

Abstract: A graphics system applies multiple layers of texture information to triangles. The graphics system includes a hardware accelerator, a frame buffer and a video output processor. The hardware accelerator receives vertices of a triangle, identifies fragments of a sampling space which intersect the triangle, and applies the multiple layers of texture to the intersecting fragments. The multiple layers of textures may be stored in a texture memory external to the hardware accelerator. The hardware accelerator switches to a next texture layer after applying the textures of a current layer to all the fragments of the triangle. The hardware accelerator includes (or couples to) a texture accumulation buffer which stores color values associated with the triangle fragments between the application of successive texture layers. The frame buffer stores the samples and pixels generated from the samples by filtration. The video output processor transforms the pixels into a video signal.