Multi Channel DMA Intel® FPGA IP for PCI Express* User Guide

ID 683821
Date 7/30/2024
Public
Document Table of Contents

5.1.7.3. MSI-X

Note: The MSI-X capability parameters cannot be set or modified if you select the MCDMA mode.
Note: The MSI-X capability parameters can be modified on BAS/BAM/BAM+BAS mode.
Table 68.  MSI-X
Parameter Value Description

Enable MSI-X

On / Off

When On, adds the MSI-X capability structure, with the parameters shown below.

Table size

15

System software reads this field to determine the MSI-X table size <n>, which is encoded as <n-1>.

Table offset

0x0000000000020000

Points to the base of the MSI-X table. The lower 3 bits of the table BAR indicator (BIR) are set to zero by software to form a 64-bit qword-aligned offset. This field is read-only after being programmed.

Table BAR indicator

0

Specifies which one of a function's base address registers, located beginning at 0x10 in the Configuration Space, maps the MSI-X table into memory space. This field is read-only.

Pending bit array (PBA) offset

0x0000000000030000

Used as an offset from the address contained in one of the function's Base Address registers to point to the base of the MSI-X PBA. The lower 3 bits of the PBA BIR are set to zero by software to form a 32-bit qword-aligned offset. This field is read-only after being programmed

PBA BAR indicator

0

Specifies the function Base Address registers, located beginning at 0x10 in Configuration Space, that maps the MSI-X PBA into memory space. This field is read-only in the MSI-X Capability Structure.

VF Table size

0

Sets the number of entries in the MSI-X table for PF0's VFs.

MSI-X cannot be disabled for VF. Set to 1 to save resources.