Intel Xeon Wolfdale E3210 P4X-UPE3210-316-6M1333 Scheda Tecnica

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Datasheet
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Host-Primary PCI Express* Bridge Registers (D1:F0)
6.29
MSI_CAPID—Message Signaled Interrupts 
Capability ID
B/D/F/Type:
0/1/0/PCI
Address Offset: 90–91h
Default Value:
A005h
Access:
RO 
Size:
16 bits
When a device supports MSI, it can generate an interrupt request to the processor by 
writing a predefined data item (a message) to a predefined memory address.
6.30
MC—Message Control
B/D/F/Type:
0/1/0/PCI
Address Offset: 92–93h
Default Value:
0000h
Access:
RW, RO 
Size:
16 bits
System software can modify bits in this register, but the device is prohibited from doing 
so.
If the device writes the same message multiple times, only one of those messages is 
ensured to be serviced. If all of them must be serviced, the device must not generate 
the same message again until the driver services the earlier one.
Bit
Access
Default 
Value
Description
15:8
RO
A0h
Pointer to Next Capability (PNC): This contains a pointer to the next item in 
the capabilities list which is the PCI Express capability.
7:0
RO
05h
Capability ID (CID): Value of 05h identifies this linked list item (capability 
structure) as being for MSI registers.
Bit
Access
Default 
Value
Description
15:8
RO
00h
Reserved 
7
RO
0b
64-bit Address Capable (64AC): Hardwired to 0 to indicate that the function 
does not implement the upper 32 bits of the Message Address register and is 
incapable of generating a 64-bit memory address. 
6:4
RW
000b
Multiple Message Enable (MME): System software programs this field to 
indicate the actual number of messages allocated to this device. This number 
will be equal to or less than the number actually requested. 
The encoding is the same as for the MMC field below. 
3:1
RO
000b
Multiple Message Capable (MMC): System software reads this field to 
determine the number of messages being requested by this device. The value of 
000b equates to 1 message requested.
000 = 1 message requested
All other encodings are reserved.
0
RW
0b
MSI Enable (MSIEN): Controls the ability of this device to generate MSIs. 
0 = 0MSI will not be generated. 
1 = MSI will be generated when we receive PME messages. INTA will not be 
generated and INTA Status (PCISTS1[3]) will not be set.