摘要:
An anti-starvation interrupt protocol for use in avoiding livelock in a multiprocessor computer system is provided. At least one processor is configured to include first and second control status registers (CSRs). The first CSR buffers information, such as interrupts, received by the processor, while the second CSR keeps track of the priority level of the interrupts. When an interrupt controller receives an interrupt, it issues a write transaction to the first CSR at the processor. If the first CSR has room to accept the write transaction, the processor returns an acknowledgement, whereas if the first CSR is already full, the processor returns a no acknowledgment. In response to a no acknowledgment, the interrupt controller increments an interrupt starvation counter, and checks to see whether the counter exceeds a threshold. If not, the interrupt controller waits a preset time and reposts the write transaction. If it does, the interrupt controller issues a write transaction having a higher priority to the second CSR. In response, the processor copies all of the pending interrupts from the first CSR into the memory subsystem, thereby freeing up the first CSR to accept additional write transactions.
摘要:
A memory system for a digital computer has first and second memory modules having differing numbers of independently-accessible banks and unlike capacities. The digital computer also has an addressing arrangement that employs horizontal stacking for interleaving together the banks of both the first and second memory modules, such that the first memory module is interleaved to a first level and the second memory module to a second, different level. The invention also embraces a method of interleaving the memory system employing horizontal stacking. In usual applications, horizontal stacking permits the memory system to be interleaved to a higher level than that achieved by conventional vertical stacking schemes.
摘要:
A method and system for completing pending I/O device reads by periodically stalling the issuance of I/O device accesses by a program in a multiple-processor computer system.
摘要:
Embodiments include writing a first data value to a validation variable through a fixed programming interface, where the validation variable includes multiple fields that correspond to multiple fields within a persistent variable. Contents of the validation variable are subsequently read through the fixed programming interface. When the validation variable contents include one or more differences from the first data value, one or more errors are identified.
摘要:
Methods and apparatus for restricted deployment of targeted processor firmware updates. During a patch enabling per-work flow, service entitlement license information comprising one of more service entitlements is generated and provisioned on one or more computing platforms. A restricted deployment microcode (uCode) update release (aka uCode patch) targeted for platforms having CPUs and/or XPUs with certain part identifier is sent to the one or more platforms. Run-time software and/or firmware on the platforms are executed to access the provisioned service entitlement license information, which is used to authentic and verify the restricted deployment uCode update release using a service entitlement having a part identifier associated with the platform's CPU. In one solution, authentication is performed using a hash-matching scheme and verification is used to verify the platform is properly licensed to load uCode included in the restricted deployment microcode (uCode) update release into the CPU.