PMC-Sierra PM5358 S/UNI 4x622 manual Calling suni4x622ISR, Suni4x622ISR and suni4x622DPR

PM5358 S/UNI-4x622 Driver Manual

Software Architecture

The driver provides system-independent functions, suni4x622ISR and suni4x622DPR. You must fill in the corresponding system-specific functions, sysSuni4x622ISRHandler and sysSuni4x622DPRTask. The system-specific functions isolate the system-specific communication mechanism (between the ISR and DPR) from the system-independent functions,

suni4x622ISR and suni4x622DPR.

Figure 6 illustrates the interrupt service model used in the S/UNI-4x622 driver design.

Figure 6: Interrupt Service Mode

Interrupt

sysSuni4x622ISRHandler Context Information

suni4x622ISR

sysSuni4x622DPRTask

suni4x622DPR

Indication Callbacks

Application

Note: Instead of using an interrupt service model, you can use a polling service model in the S/UNI-4x622 driver to process the device’s event-indication registers (see page 26).

Calling suni4x622ISR

An interrupt handler function, which is system dependent, must call suni4x622ISR. But first, the low-level interrupt-handler function must trap the device interrupts. You must implement this function to fit your own system. As a reference, an example implementation of the interrupt handler (sysSuni4x622ISRHandler) appears on page 110. You can customize this example implementation to suit your needs.

The interrupt handler that you implement (sysSuni4x622ISRHandler) is installed in the interrupt vector table of the system processor. It is called when one or more S/UNI-4x622 devices interrupt the processor. The interrupt handler then calls suni4x622ISR for each device in the active state that has interrupt processing enabled.

The suni4x622ISR function reads from the master interrupt-status registers and the miscellaneous interrupt-status registers of the S/UNI-4x622. If at least one valid interrupt condition is found then suni4x622ISR fills an Interrupt-Service Vector (ISV) with this status information as well as the current device handle. The suni4x622ISR function also clears and disables all the device’s interrupts detected. The sysSuni4x622ISRHandler function is then responsible to send this ISV buffer to the DPR task.

Note: Normally you should save the status information for deferred processing by implementing a message queue. The interrupt handler sends the status information to the queue by the

sysSuni4x622ISRHandler.

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Document ID: PMC-2010419, Issue 1