Host-PCI Express* Graphics Bridge Registers (D1:F0)
R
132
Intel
®
82925X/82925XE MCH Datasheet
8.1.28
MC—Message Control (D1:F0)
PCI Device:
1
Address Offset:
92h
Default Value:
0000h
Access: RO,
R/W
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 guaranteed 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
Description
15:8
Reserved
7 RO
0b
64-bit Address Capable:
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 R/W
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.
000 = 1 message allocated
001–111 = Reserved
3:1 RO
000b
Multiple Message Capable (MMC):
System software reads this field to
determine the number of messages being requested by this device.
000 = 1 message requested
001–111 = Reserved
0 R/W
0b
MSI Enable (MSIEN)
Controls the ability of this device to generate MSIs.
0 = MSI will not be generated.
1 = MSI will be generated when we receive PME or HotPlug messages. INTA will
not be generated and INTA Status (PCISTS1[3]) will not be set.
Summary of Contents for 82925X
Page 78: ...Host Bridge DRAM Controller Registers D0 F0 R 78 Intel 82925X 82925XE MCH Datasheet...
Page 98: ...EPBAR Registers Egress Port Register Summary R 98 Intel 82925X 82925XE MCH Datasheet...
Page 108: ...DMIBAR Registers Direct Media Interface DMI RCRB R 108 Intel 82925X 82925XE MCH Datasheet...
Page 156: ...Host PCI Express Graphics Bridge Registers D1 F0 R 156 Intel 82925X 82925XE MCH Datasheet...
Page 172: ...System Address Map R 172 Intel 82925X 82925XE MCH Datasheet...
Page 192: ...Electrical Characteristics R 192 Intel 82925X 82925XE MCH Datasheet...