Chapter 6: IP Core Interfaces
6–41
Transaction Layer Configuration Space Signals
November 2012
Altera Corporation
Arria V GZ Hard IP for PCI Express
shows the layout of the Configuration MSI Control Status register.
describes the use of the various fields of the Configuration MSI Control
and Status Register.
cfg_msi_data
16
O
cfg_msi_data[15:0]
is message data for MSI.
0x050
cfg_busdev
13
O
Bus/Device Number captured by or programmed in the Hard IP.
0x08
Table 6–16. Configuration Space Register Descriptions (Part 4 of 4)
Register
Width
Dir
Description
Register
Reference
Table 6–17. Configuration MSI Control Status Register
Field and Bit Map
15
9
8
7
6
4
3
0
reserved
mask
capability
64-bit
address
capability
multiple message enable
multiple message
capable
MSI
enable
Table 6–18. Configuration MSI Control Status Register Field Descriptions (Part 1 of 2)
Bit(s)
Field
Description
[15:9]
reserved
—
[8]
mask
capability
Per vector masking capable. This bit is hardwired to 0 because the function does not
support the optional MSI per vector masking using the
Mask_Bits
and
Pending_Bits
registers defined in the
PCI Local Bus Specification, Rev. 3.0
vector masking can be implemented using Application Layer registers.
[7]
64-bit
address
capability
64-bit address capable.
■
1: function capable of sending a 64-bit message address
■
0: function not capable of sending a 64-bit message address
[6:4]
multiple
message
enable
Multiple message enable: This field indicates permitted values for MSI signals. For
example, if “100” is written to this field 16 MSI signals are allocated
■
3’b000: 1 MSI allocated
■
3’b001: 2 MSI allocated
■
3’b010: 4 MSI allocated
■
3’b011: 8 MSI allocated
■
3’b100: 16 MSI allocated
■
3’b101: 32 MSI allocated
■
3’b110: Reserved
■
3’b111: Reserved