GIET_VM / PIC Driver

The pic_driver.c​ and pic_driver.h​ files define the PIC driver.

The vci_pic component is a multi-channels interrupt controller, available in the SoCLib components library. This component translate an hardware interrupt generated by an external peripheral (HWI) to a write-triggered interrupt (WTI) that will be sent to an internal vci_xcu in a given cluster. The PIC component is therefore an external, non replicated peripheral.

The SEG_PIC_BASE value must be defined in the hard_config.h file.

The addressable registers map is defined here​.

Low level access functions

void _pic_set_register( unsigned int irq_id, unsigned int index, unsigned int value )

This function set a new value in register identified by (irq_id / index).

• irq_id : input IRQ index.
• index : register offset.
• value : value to be written.

unsigned int _pic_get_register( unsigned int irq_id, unsigned int index )

This function returns the value of register identified by (channel / index).

• irq_id : input IRQ index.
• index : register offset.

access functions

void _pic_init( unsigned int irq_id, unsigned int vaddr, unsigned int extend )

This function initializes and activates a given external IRQ in the PIC component. It writes an XCU mailbox physical address in the IOPIC_ADDRESS and IOPIC_EXTEND registers, and enables the channel.

• irq_id : input IRQ index.
• vaddr : address of the destination XCU register
• extend : cluster_xy for the destination XCU

void _pic_enable( unsigned int irq_id )

This function enables a given external IRQ. The associated WTI maibox address is not modified.

• irq_id : source PIC HWI channel

void _pic_disable( unsigned int irq_id)

This function disables a given given external IRQ. The associated WTI maibox address is not modified.

• irq_id : source PIC HWI channel

unsigned int _pic_get_status( unsigned int irq_id )

This function returns the status of a given HWI.

• irq_id : source PIC HWI channel