摘要:
A method and apparatus for powering down a computer system while saving the state of the system at power down is disclosed. The system maintains the capability to suspend the execution of an application program operating on the system at any point and resuming execution of the application program at that same point at a later time. The time at which the system may be powered down and then powered back up again is totally arbitrary and depends only upon the user of the system. At the time the system is powered off, the contents of all active registers as well as the states of all I/O devices in the system are stored in a special save area of system memory. This special save area is provided with power during the suspended time in order to retain the state of the system at the time it was powered down. By using this special save suspend area, the main memory area of the system is available to any application programs independently of the system save memory requirements. Additionally, the system may be powered on and off under software control thereby providing the capability for unattended system operation using an alarm function.
摘要:
A method for communicating instructions and data between a processor and external devices are provided. The method makes use of a channel interface as the primary mechanism for communicating between the processor and a memory flow controller. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.
摘要:
A method and apparatus for instruction parity error recovery in a programmable data processor wherein the instruction parity error is logged for future reference, the instruction causing the error is reloaded to memory and the program is restarted at the point of error. This method for "soft" recovery from an instruction parity error forces a No-Operation instruction onto the processor's instruction bus in place of the faulty instruction when a parity error is detected during instruction fetch, stores the address of the instruction having the parity error, and forces the next instruction to the processor from a parity error recovery routine. The parity error recovery routine logs the error, restores the instruction from local disk storage or from a remote host system in communication with the programmable data processor and forces the processor to resume fetching instructions at the address where the error occurred.
摘要:
A system and method for communicating with a processor event facility are provided. The system and method make use of a channel interface as the primary mechanism for communicating with the processor event facility. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.
摘要:
A system for limiting the size of a local storage of a processor is provided. A facility is provided in association with a processor for setting a local storage size limit. This facility is a privileged facility and can only be accessed by the operating system running on a control processor in the multiprocessor system or the associated processor itself. The operating system sets the value stored in the local storage limit register when the operating system initializes a context switch in the processor. When the processor accesses the local storage using a request address, the local storage address corresponding to the request address is compared against the local storage limit size value in order to determine if the local storage address, or a modulo of the local storage address, is used to access the local storage.
摘要:
A method for limiting the size of a local storage of a processor is provided. A facility is provided in association with a processor for setting a local storage size limit. This facility is a privileged facility and can only be accessed by the operating system running on a control processor in the multiprocessor system or the associated processor itself The operating system sets the value stored in the local storage limit register when the operating system initializes a context switch in the processor. When the processor accesses the local storage using a request address, the local storage address corresponding to the request address is compared against the 1ocal storage limit size value in order to determine if the local storage address, or a modulo of the local storage address, is used to access the local storage.
摘要:
A system and method for providing a mediated external exception extension for a microprocessor are provided. With the system and method, in response to an external exception, a hypervisor determines if the associated external interrupt is directed to a logical partition (LPAR) that has external interrupt handling enabled. If so, the hypervisor sets appropriate state restore registers (SRRs) and passes control to an external interrupt handler of the LPAR. If external interrupt handling is not currently enabled by the LPAR, the hypervisor sets a mediated exception request and returns control to the LPAR. Once the operating system of the logical partition re-enables external interrupt handling, a mediated external interrupt occurs, state information for the LPAR is set in the SRRs, and the external interrupt handler of the LPAR is invoked. In this way, external interrupts may be received by the hypervisor even when external interrupt handling is disabled.
摘要:
Mechanisms for communicating with a processor event facility are provided. The mechanisms make use of a channel interface as the primary mechanism for communicating with the processor event facility. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.
摘要:
A mechanism for communicating instructions and data between a processor and external devices are provided. The mechanism makes use of a channel interface as the primary mechanism for communicating between the processor and a memory flow controller. The channel interface provides channels for communicating with processor facilities, memory flow control facilities, machine state registers, and external processor interrupt facilities, for example. These channels may be designated as blocking or non-blocking. With blocking channels, when no data is available to be read from the corresponding registers, or there is no space available to write to the corresponding registers, the processor is placed in a low power “stall” state. The processor is automatically awakened, via communication across the blocking channel, when data becomes available or space is freed. Thus, the channels of the present invention permit the processor to stay in a low power state.
摘要:
Exemplary embodiments include a method for enhancing lock acquisition in a multiprocessor system, the method including: sending a lock-load instruction from a first processor to a cache; setting a reservation flag for the first processor, storing a reservation address, storing a shadow register number, and sending lock data to the first processor in response to the lock-load instruction; placing the lock data in target and shadow registers of the first processor; determining from the lock data whether lock is taken; resending the lock-load instruction from the first processor to the cache upon a determination that the lock is taken; determining whether the reservation flag is still set and its main memory address and shadow register number match with the saved reservation address and shadow register number for the first processor; sending a status-quo signal to the first processor without resending the lock data to the first processor upon a determination that the reservation flag is still set for the first processor; and copying the lock data from the associated shadow register to the target register in response to the status-quo signal.