Arria V Avalon-ST Interface for PCIe Solutions User Guide
3.4.6. Func <n> MSI and MSI-X Capabilities
|   Parameter  |  
        Value  |  
        Description  |  
     
|---|---|---|
|   MSI messages requested  |  
        1, 2, 4, 8, 16, 32  |  
        Specifies the number of messages the Application Layer can request. Sets the value of the Multiple Message Capable field of the Message Control register, 0x050[31:16].  |  
     
| MSI-X Capabilities | ||
|   Implement MSI-X  |  
        On/Off  |  
        When On, enables the MSI-X functionality.  |  
     
| Bit Range | ||
|   Table size  |  
        [10:0]  |  
        System software reads this field to determine the MSI-X Table size <n>, which is encoded as <n–1>. For example, a returned value of 2047 indicates a table size of 2048. This field is read-only. Legal range is 0–2047 (211). Address offset: 0x068[26:16]  |  
     
|   Table Offset  |  
        [31:0]  |  
        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 32-bit qword-aligned offset 4. This field is read-only.  |  
     
|   Table BAR Indicator  |  
        [2:0]  |  
        Specifies which one of a function’s BARs, located beginning at 0x10 in Configuration Space, is used to map the MSI-X table into memory space. This field is read-only. Legal range is 0–5.  |  
     
|   Pending Bit Array (PBA) Offset  |  
        [31:0]  |  
        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.  |  
     
| PBA BAR Indicator |   [2:0]  |  
        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. Legal range is 0–5.  |