Abstract: A cache memory logically associates a cache line with at least two cache sectors of a cache array wherein different sectors have different output latencies and, for a load hit, selectively enables the cache sectors based on their latency to output the cache line over successive clock cycles. Larger wires having a higher transmission speed are preferably used to output the cache line corresponding to the requested memory block. In the illustrative embodiment the cache is arranged with rows and columns of the cache sectors, and a given cache line is spread across sectors in different columns, with at least one portion of the given cache line being located in a first column having a first latency, and another portion of the given cache line being located in a second column having a second latency greater than the first latency.

Abstract: A symmetric multiprocessor data processing system (SMP) that implements a TLBI protocol, which enables multiple TLBI operations from multiple processors to complete without causing delay. Each processor includes a TLBI register associated with the TLB and TLBI logic. The TLBI register includes a sequence of bits utilized to track the completion of a TLBI issued by the processor at the other processors. Each bit corresponds to a particular processor across the system and the particular processor is able to directly set the bit in the register of a master processor once the particular processor completes a TLBI operation initiated from the master processor. The master processor is able to track completion of the TLBI operation by checking the values of each bit within its TLBI register, without requiring multi-issuance of an address-only barrier operation on the system bus.

Abstract: A cache memory logically associates a cache line with at least two cache sectors of a cache array wherein different sectors have different output latencies and, for a load hit, selectively enables the cache sectors based on their latency to output the cache line over successive clock cycles. Larger wires having a higher transmission speed are preferably used to output the cache line corresponding to the requested memory block. In the illustrative embodiment the cache is arranged with rows and columns of the cache sectors, and a given cache line is spread across sectors in different columns, with at least one portion of the given cache line being located in a first column having a first latency, and another portion of the given cache line being located in a second column having a second latency greater than the first latency.

Abstract: A cache memory logically partitions a cache array into at least two slices each having a plurality of cache lines, with a given cache line spread across two or more cache ways of contiguous bytes and a given cache way shared between the two cache slices, and if one a cache way is defective that is part of a first cache line in the first cache slice and part of a second cache line in the second cache slice, it is disabled while continuing to use at least one other cache way which is also part of the first cache line and part of the second cache line. In the illustrative embodiment the cache array is set associative and at least two different cache ways for a given cache line contain different congruence classes for that cache line. The defective cache way can be disabled by preventing an eviction mechanism from allocating any congruence class in the defective way. For example, half of the cache line can be disabled (i.e., half of the congruence classes).

Abstract: A method of correcting an error in an ECC protected mechanism of a computer system, such as a cache or system bus, by applying data with a number of bits N to an error correction code (ECC) matrix to yield an error detection syndrome, wherein the ECC matrix has a plurality of rows and columns with a given column corresponding to a respective one of the data bits, and selected bits are set in the ECC matrix along each column and each row such that encoding for the ECC matrix allows N-bit error correction and (N?1)-bit error detection. When an error is detected and after it is corrected, the corrected data is inverted and then rewritten to the cache array. The corresponding inversion bit for this entry is accordingly set to indicate that the data as currently stored is inverted.

Abstract: Disclosed is a symmetric multiprocessor data processing system (SMP) that implements a TLBI protocol, which enables multiple TLBI operations from multiple processors within a partition to complete concurrently. Thus, a global TLB lock, synchronization, and TLB unlock is not necessary. When a TLBI instruction is executed, the master dynamically manages the behavior of the TLBI operation based on asynchronously snooping another TLBI. If concurrent TLBI management is required, then the master dynamically degrades the TLBI to a “barrier” class instruction.

Abstract: A method of correcting an error in an ECC protected mechanism of a computer system, such as a cache or system bus, by applying data with a number of bits N to an error correction code (ECC) matrix to yield an error detection syndrome, wherein the ECC matrix has a plurality of rows and columns with a given column corresponding to a respective one of the data bits, and selected bits are set in the ECC matrix along each column and each row such that encoding for the ECC matrix allows N-bit error correction and (N?1)-bit error detection. In the illustrative embodiment, the ECC matrix has an odd number of bits set in each row thereof. In the case of an ECC protected mechanism such as a memory device, these properties facilitate the use of an inversion bit for correcting hard faults in the stored data. When an error is detected and after it is corrected, the corrected data is inverted and then rewritten to the cache array.

Abstract: A symmetric multiprocessor data processing system (SMP) that implements a TLBI protocol, which enables multiple TLBI operations from multiple processors to complete without causing delay. Each processor includes a TLBI register associated with the TLB and TLBI logic. The TLBI register includes a sequence of bits utilized to track the completion of a TLBI issued by the processor at the other processors. Each bit corresponds to a particular processor across the system and the particular processor is able to directly set the bit in the register of a master processor once the particular processor completes a TLBI operation initiated from the master processor. The master processor is able to track completion of the TLBI operation by checking the values of each bit within its TLBI register, without requiring multi-issuance of an address-only barrier operation on the system bus.

Abstract: Disclosed is a symmetric multiprocessor data processing system (SMP) that implements a TLBI protocol, which enables multiple TLBI operations from multiple processors within a partition to complete concurrently. Thus, a global TLB lock, synchronization, and TLB unlock is not necessary. When a TLBI instruction is executed, the master dynamically manages the behavior of the TLBI operation based on asynchronously snooping another TLBI. If concurrent TLBI management is required, then the master dynamically degrades the TLBI to a “barrier” class instruction.

Abstract: A method of correcting an error in an ECC protected mechanism of a computer system, such as a cache or system bus, by applying data with a number of bits N to an error correction code (ECC) matrix to yield an error detection syndrome, wherein the ECC matrix has a plurality of rows and columns with a given column corresponding to a respective one of the data bits, and selected bits are set in the ECC matrix along each column and each row such that encoding for the ECC matrix allows N-bit error correction and (N−1)-bit error detection. In the illustrative embodiment, the ECC matrix has an odd number of bits set in each row thereof. In the case of an ECC protected mechanism such as a memory device, these properties facilitate the use of an inversion bit for correcting hard faults in the stored data. When an error is detected and after it is corrected, the corrected data is inverted and then rewritten to the cache array.

Abstract: A method of correcting an error in an ECC protected mechanism of a computer system, such as a cache or system bus, by applying data with a number of bits N to an error correction code (ECC) matrix to yield an error detection syndrome, wherein the ECC matrix has a plurality of rows and columns with a given column corresponding to a respective one of the data bits, and selected bits are set in the ECC matrix along each column and each row such that encoding for the ECC matrix allows N-bit error correction and (N−1)-bit error detection. In the illustrative embodiment, the ECC matrix has an odd number of bits set in each row thereof. In the case of an ECC protected mechanism such as a memory device, these properties facilitate the use of an inversion bit for correcting hard faults in the stored data. When an error is detected and after it is corrected, the corrected data is inverted and then rewritten to the cache array.