Chapter 7: Register Descriptions
7–13
PCI Express Avalon-MM Bridge Control Register Access Content
June 2012
Altera Corporation
Stratix V Hard IP for PCI Express
Table 7–25
shows the status of all conditions that can cause a PCI Express interrupt to
be asserted.
A PCI Express interrupt can be asserted for any of the conditions registered in the
Avalon-MM to
PCI Express
Interrupt Status
register by setting the corresponding
bits in the Avalon-MM-to-PCI Express
Interrupt Enable
register (
Table 7–26
). Either
MSI or legacy interrupts can be generated as explained in the section
or Legacy Interrupts” on page 11–7
.
Table 7–26
describes the
Avalon-MM to PCI Express Interrupt Enable
register.
Table 7–25. Avalon-MM to PCI Express Interrupt Status Register
0x0040
Bit
Name
Access Description
[31:24]
Reserved
—
—
[23]
A2P_MAILBOX_INT7
RW1C
1 when the A2P_MAILBOX7 is written to
[22]
A2P_MAILBOX_INT6
RW1C
1 when the A2P_MAILBOX6 is written to
[21]
A2P_MAILBOX_INT5
RW1C
1 when the A2P_MAILBOX5 is written to
[20]
A2P_MAILBOX_INT4
RW1C
1 when the A2P_MAILBOX4 is written to
[19]
A2P_MAILBOX_INT3
RW1C
1 when the A2P_MAILBOX3 is written to
[18]
A2P_MAILBOX_INT2
RW1C
1 when the A2P_MAILBOX2 is written to
[17]
A2P_MAILBOX_INT1
RW1C
1 when the A2P_MAILBOX1 is written to
[16]
A2P_MAILBOX_INT0
RW1C
1 when the A2P_MAILBOX0 is written to
[15:0]
AVL_IRQ_ASSERTED[15:0]
RO
Current value of the Avalon-MM interrupt (IRQ) input
ports to the Avalon-MM RX master port:
■
0 – Avalon-MM IRQ is not being signaled.
■
1 – Avalon-MM IRQ is being signaled.
A Qsys-generated IP Compiler for PCI Express has as
many as 16 distinct IRQ input ports. Each
AVL_IRQ_ASSERTED[]
bit reflects the value on the
corresponding IRQ input port.
Table 7–26. Avalon-MM to PCI Express Interrupt Enable Register
0x0050
Bits
Name
Access Description
[31:24]
Reserved
—
—
[23:16]
A2P_MB_IRQ
RW
Enables generation of PCI Express interrupts when a
specified mailbox is written to by an external
Avalon-MM master.
[15:0]
AVL_IRQ[15:0]
RX
Enables generation of PCI Express interrupts when a
specified Avalon-MM interrupt signal is asserted. Your
Qsys system may have as many as 16 individual input
interrupt signals.