Abstract: Mechanisms are provided for efficient storage of meta-bits within a system memory. The mechanisms combine an L/G bit and an SUE bit to form meta-bits. The mechanisms then determine the local/global state of a cache line on the first cycle of data. The mechanisms forward the data to the requesting cache, and the requesting cache may reissue the request globally based on the local/global state of the cache line. The mechanisms then determine the special uncorrectable error state of the cache line on the second or subsequent cycle of data. The mechanisms perform error processing regardless of whether the request was reissued globally.

Abstract: Mechanisms are provided for efficient storage of meta-bits within a system memory. The mechanisms combine an L/G bit and an SUE bit to form meta-bits. The mechanisms then determine the local/global state of a cache line on the first cycle of data. The mechanisms forward the data to the requesting cache, and the requesting cache may reissue the request globally based on the local/global state of the cache line. The mechanisms then determine the special uncorrectable error state of the cache line on the second or subsequent cycle of data. The mechanisms perform error processing regardless of whether the request was reissued globally.

Abstract: The present invention provides a system and method for controlling data entries in a hierarchical buffer system. The system includes an integrated circuit device with a memory core, a high speed upstream data bus, and a plurality of 1st tier buffers that receive data from the memory. The system further includes a 2nd tier transfer buffer spanning a plurality of asynchronous timing domains that delivers the data onto the upstream data bus to minimize gaps in a data transfer. The method includes managing the buffers to allow data to flow from a plurality of 1st tier buffers through a 2nd tier transfer buffer, and delivering the data onto a high speed data bus with pre-determined timing in a manner which minimizes latency to the extent that the returning read data beats are always transmitted contiguously with no intervening gaps.

Abstract: The present invention provides a system and method for controlling data entries in a hierarchical buffer system. The system includes an integrated circuit device comprising: a memory core, a shared data bus, and a plurality of 1st tier buffers that receive data from the memory. The system further includes a 2nd tier transfer buffer that delivers the data onto the shared data bus with pre-determined timing. The present invention can also be viewed as providing methods for controlling moving data entries in a hierarchical buffer system. The method includes managing the buffers to allow data to flow from a plurality of 1st tier buffers through a 2nd tier transfer buffer, and delivering the data onto a shared data bus with pre-determined timing.

Abstract: Systems and methods for providing automatic read flow control in a cascade interconnect memory system. A hub device includes an interface to a channel in a cascade interconnect memory system for connecting the hub device to an upstream hub device or a memory controller. The channel includes an upstream bus and a downstream bus. The hub device also includes read data flow control logic for determining when to transmit data on the upstream bus. The determining is responsive to an order of commands received on the downstream bus and to current traffic on the upstream bus.

Abstract: A logical design including multiple logical blocks is mapped onto an integrated circuit chip. A chip level floor plan is created on the chip, including temporary areas on the chip set aside for accommodating logical blocks having logical content including timing requirements based on the logical design. The temporary areas are translated into physical cells on the chip with pins assigned for inputs and outputs for the logical blocks. The logical blocks are mapped to the physical cells on the chip in a time sensitive manner using timing assertions to form temporary logical partitions. Blocks on the chip, including the temporary logical partitions, are connected based on the timing assertions. A timing analysis is performed on the chip to determine timing slack associated with each temporary logical partition. A determination is made whether the timing slack is acceptable.

Abstract: A synchronous input to output protocol translator supporting multiple reference oscillator frequencies and fixed latency data computation and chip crossing circuits enables implementation of a method for delaying osc2 relative to osc1 in a configurable way to provide a constant, minimal Tptcc over a range of refosc frequencies between circuits for data transferred. It requires that the data transferred from a register R1 be sent over multiple wires via configurable delay circuitry for osc2, capture circuitry at the input to R2, and a circuit to transfer a synchronizing signal from a non-delayed clock domain to a delayed clock domain. Relative to osc1, osc2 is a delayed, synchronous clock.