SocLib Components General Index

VciIcu

1) Functional Description

This VCI target is a memory mapped peripheral implementing a vectorized interrupt controller. It can concentrate up to 32 independent interrupt lines p_irq_in[i] to a single p_irq interrupt line.

The active state is high, and the output interrupt is the logical OR of all input interrupts. Each input interrupt can be individually masked through a programmable register.

This component can be addressed to return the index of the highest priority active interrupt p_irq_[i]. The priority scheme is fixed : The lower indexes have the highest priority.

This hardware component checks for segmentation violation, and can be used as a default target.

This component contains 5 memory mapped registers:

• ICU_INT Each bit in this register reflects the state of the corresponding interrupt line. This is read-only.

• ICU_MASK Each bit in this register reflects the state of the enable for the corresponding interrupt line. This is read-only.

• ICU_MASK_SET Each bit set in the written word will be set in the ICU MASK. (ICU_MASK = ICU_MASK | written_data). This is write-only.

• ICU_MASK_CLEAR Each bit set in the written word will be reset in the ICU MASK. (ICU_MASK = ICU_MASK & ~written_data). This is write-only.

• ICU_IT_VECTOR This register gives the number of the highest-priority active interrupt. If no interrupt is active, (-1) is returned. This is read-only.

For extensibility issues, you should access your ICU using globally-defined offsets.

You should include file soclib/icu.h from your software, it defines ICU_INT, ICU_MASK, ICU_MASK_SET, ICU_MASK_CLEAR, ICU_IT_VECTOR.

Sample code:

#include "soclib/icu.h"

static const volatile void* icu_address = 0xc0000000;

static icu_test()
{
    // Getting / setting interrupt mask
    uint32_t current_interrupt_mask = soclib_io_get( icu_address, ICU_MASK );

    // Enabling IRQ #5
    soclib_io_set( icu_address, ICU_MASK_SET, 1<<5 );
    // Disabling IRQ #0
    soclib_io_set( icu_address, ICU_MASK_CLEAR, 1<<0 );

    // When interrupt is raised, you may do:
    int irq_to_serve = soclib_io_get( icu_address, ICU_IT_VECTOR );
    // This should be equivalent to (see man 3 ffs)
    int irq_to_serve = ffs( soclib_io_get( icu_address, ICU_IT_VECTOR )
                          & soclib_io_get( icu_address, ICU_MASK ) );
}

(add -I/path/to/soclib/include to your compilation command-line)

2) Component definition & usage

source:trunk/soclib/module/infrastructure_component/interrupt_infrastructure/vci_icu/caba/metadata/vci_icu.sd

See SoclibCc/VciParameters

Uses( 'vci_icu', **vci_parameters )

3) CABA Implementation

CABA sources

• interface : source:trunk/soclib/soclib/module/infrastructure_component/interrupt_infrastructure/vci_icu/caba/source/include/vci_icu.h​
• implementation : source:trunk/soclib/soclib/module/infrastructure_component/interrupt_infrastructure/vci_icu/caba/source/src/vci_icu.cpp​

CABA Constructor parameters

VciIcu(
     sc_module_name name,  // Component Name
     const soclib::common::InTab &index, // Target index
     const soclib::common::MappingTable &mt,  // Mapping Table
     size_t nirq);  // Number of input interrupts

CABA Ports

• sc_in<bool> p_resetn : Global system reset
• sc_in<bool> p_clk : Global system clock
• soclib::caba::VciTarget<vci_param> p_vci : VCI port
• sc_out<bool> p_irq : Output interrupt port
• sc_in<bool> p_irq_in[] : Input interrupts ports array