An information handling system sets up at power-on self-test, a system management interrupt based on a trap on an input/output port used for a real-time clock and detects at runtime, an operation on the input/output port. In response to detecting the operation on the input/output port, generates the system management interrupt based on the trap on the input/output port. In addition, the information handling system handles the system management interrupt by emulating the real-time clock according to the operation on the input/output port that includes determining a register that is mapped to an index associated with the operation and accessing the register and executing a function associated with the register.

Within an interrupt routing structure, an interrupt handler is registered, the registering comprising storing a pointer to the interrupt handler in the interrupt routing structure. Responsive to determining that a received interrupt comprises a queuing bypass flag in a set state, the interrupt handler is executed, the executing bypassing an interrupt queueing mechanism.

Within an interrupt routing structure, an interrupt handler is registered, the registering comprising storing a pointer to the interrupt handler in the interrupt routing structure. Responsive to determining that a received interrupt comprises a queuing bypass flag in a set state, the interrupt handler is executed, the executing bypassing an interrupt queueing mechanism.

The present disclosure relates to a communication method by I2C bus between a emitting device and a receiving device, in which: a rising edge of a clock signal of the I2C bus, directly following a start condition of an I2C communication, is recorded; and when an interruption is generated within the receiving device, the receiving device verifies whether the rising edge was recorded.

The present disclosure relates to a communication method by I2C bus between a emitting device and a receiving device, in which: a rising edge of a clock signal of the I2C bus, directly following a start condition of an I2C communication, is recorded; and when an interruption is generated within the receiving device, the receiving device verifies whether the rising edge was recorded.

Methods, systems, and apparatuses provide support for multiple address spaces in order to facilitate data movement. One system includes a host processor; a memory; a data fabric coupled to the host processor and to the memory; a first input/output memory manage unit (IOMMU) and a second IOMMU, each of the first and second IOMMUs coupled to the data fabric; a first root port and a second root port, each of the first and second root ports coupled to a corresponding IOMMU of the first and second IOMMUs; and a first peripheral component endpoint and a second peripheral component endpoint, each of the first and second peripheral component endpoints coupled to a corresponding root port of the first and second root ports, wherein each of the first and second root ports comprises hardware control logic operative to: synchronize the first and second root ports.

Methods, systems, and apparatuses provide support for multiple address spaces in order to facilitate data movement. One system includes a host processor; a memory; a data fabric coupled to the host processor and to the memory; a first input/output memory manage unit (IOMMU) and a second IOMMU, each of the first and second IOMMUs coupled to the data fabric; a first root port and a second root port, each of the first and second root ports coupled to a corresponding IOMMU of the first and second IOMMUs; and a first peripheral component endpoint and a second peripheral component endpoint, each of the first and second peripheral component endpoints coupled to a corresponding root port of the first and second root ports, wherein each of the first and second root ports comprises hardware control logic operative to: synchronize the first and second root ports.

Techniques are disclosed relating to address mapping for message signaled interrupts. In some embodiments, an apparatus includes interrupt control circuitry configured to process, from multiple client circuits, message signaled interrupts that include addresses in an interrupt controller address space. First and second interface controller circuitry may control respective peripheral interfaces for multiple devices. Remap control circuitry may be configured to access a first table based on at least a portion of virtual addresses of a first message signaled interrupt from the first interface controller circuit and generate a first address in the interrupt controller address space based on an accessed entry in the first table and access a second table based on at least a portion of virtual addresses of a second message signaled interrupt from the second interface controller circuit and generate a second address in the interrupt controller address space based on an accessed entry in the second table.

Techniques are disclosed relating to address mapping for message signaled interrupts. In some embodiments, an apparatus includes interrupt control circuitry configured to process, from multiple client circuits, message signaled interrupts that include addresses in an interrupt controller address space. First and second interface controller circuitry may control respective peripheral interfaces for multiple devices. Remap control circuitry may be configured to access a first table based on at least a portion of virtual addresses of a first message signaled interrupt from the first interface controller circuit and generate a first address in the interrupt controller address space based on an accessed entry in the first table and access a second table based on at least a portion of virtual addresses of a second message signaled interrupt from the second interface controller circuit and generate a second address in the interrupt controller address space based on an accessed entry in the second table.

A problem to be solved by the present invention is, in a computer system, to reduce processing delay from wait times which occur in timer access. According to the present invention, using either a CPU core (hereinafter “processing core”) other than a CPU core which executes an application, or a DMA device, a latest timer value is always transferred from a timer device to a primary storage device. The processing core reads the transferred value upon the primary storage device instead of accessing a register of the timer device, thereby avoiding a wait which occurs when directly reading the timer value of the timer device. The transfer of the value is carried out asynchronously from the processing of the processing core, thus obviating the need for the processing core to wait for the completion of the transfer. Accordingly, it is also unnecessary for the processing core to process an interrupt or a notification from another CPU core or the DMA device.