PCI Configuration Registers
BCM5718 Programmer’s Guide
Broadcom
®
January 29, 2016 • 5718-PG108-R
Page 281
MSI Capability Header (offset: 0x58)
The device driver is prohibited from writing to this register.
Name
Bits
Access
Default
Value
Description
MSI Control
31:25
RO
0x00
Reserved
MSI_PVMASK_
CAPABLE
24
RO
0
This bit indicates if the function supports per vector
masking. This value comes from the MSI_PV_MASK_CAP
bit in the register space.
64-bit Address
Capable
23
RO
1
Hardwired
Advertise 64-bit address capable
This bit indicates that the chip is capable of generating 64
bit MSI messages.
Multiple Message
Enable
22:20
RW
0x0
These bits indicate the number of message that the chip is
configured (allowed) to generate. Number of allocated
message:
0
1
Chip is set to generate 1 message
1
2
Chip is set to generate 2 messages
2
4
Chip is set to generate 4 messages
3
8
Chip is set to generate 8 messages
4
16
Chip is set to generate 16 messages
5
32
Chip is set to generate 32 messages
Multiple Message
Capable
19:17
RO
0x3
These bits indicate the number of messages that the chip
is capable of generating. This value comes from the bit in
the register space. Number of requested message:
0
1
Chip is set to generate 1 message
1
2
Chip is set to generate 2 messages
2
4
Chip is set to generate 4 messages
3
8
Chip is set to generate 8 messages
4
16
Chip is set to generate 16 messages
5
32
Chip is set to generate 32 messages
MSI Enable
16
RW
0
When this bit is set, the chip will generate MSI cycles to
indicate interrupts instead of asserting the INTA# pin.
When this bit is zero, the INTA# pin will be used.
Next Capability
Pointer
15:8
RO
A0
This value continues the PCI capability chain. It's value
specified an offset in the PCI address space of the next
capability. The read-only value of this register is controlled
by the CAP_ENA register in the PCI register space.
MSI capability ID
7:0
RO
0x5
The 8-bit MSI Capability ID is set to 5 to indicate that the
next 8 bytes are a Message Signaled Interrupt capability
block.