PCI Configuration RegistersBCM5718 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.