am79c972b Advanced Micro Devices, am79c972b Datasheet - Page 104

• Manufacturer Part Number: am79c972b
• Description: Pcnet?-fast+ Enhanced 10/100 Mbps Pci Ethernet Controller With Onnow Support
• Manufacturer: Advanced Micro Devices

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D2_SPT
D1_SPT
RES
DSI
AUXPS
PME_CLK
D2 Support. If this bit is a 1, this
function supports the D2 Power
Management State.
Read only.
D1 Support. If this bit is a 1, this
function supports the D1 Power
Management State.
Read only.
Reserved locations. Written as
zeros and read as undefined.
Device
When this bit is 1, it indicates that
special initialization of the func-
tion is required (beyond the stan-
dard PCI configuration header)
before the generic class device
driver is able to use it.
Read only.
Auxiliary Power Source. This bit
is only meaningful if bit 15
(D3cold supporting PME) is a 1.
When this bit is also a 1, it indi-
cates that support for PME in
D3cold requires auxiliary power
supplied by the system by way of
a proprietary delivery vehicle.
A 0 in this bit indicates that the
function supplies its own auxiliary
power source.
If the function does not support
PME while in D3cold, (bit15=0)
then this field must always return
0.
Read only.
PME Clock. When this bit is a 1,
it indicates that the function relies
on the presence of the PCI clock
for PME operation. When this bit
is a 0 it indicates that no PCI
clock is required for the function
to generate PME.
Functions that do not support
PME generation in any state
must return 0 for this field.
Read only.
Specific
Initialization.
Am79C972
2-0
PCI Power Management Control/Status Register
(PMCSR)
Offset 44h
Bit
15
14-13 DATA_SCALE
12-9
PME_STATUS PME Status. This bit is set when
PMIS_VER Power Management Interface
Name
DATA_SEL Data Select. This optional four-bit
Specification Version. A value of
001b indicates that this function
complies with the revision 1.0 of
the PCI Power Management In-
terface Specification.
the function would normally as-
sert the PME signal independent
of the state of the PME_EN bit.
and cause the function to stop as-
serting a PME (if enabled). Writ-
ing a 0 has no effect.
D3cold then this bit is sticky and
must be explicitly cleared by the
operating system each time the
operating system is initially load-
ed.
Sticky bit. This bit is reset by
POR. H_RESET, S_RESET, or
setting the STOP bit has no ef-
fect.
only field indicates the scaling
factor to be used when interpret-
ing the value of the Data register.
The value and meaning of this
field will vary depending on the
DATA_SCALE field.
field is used to select which data
is reported through the Data reg-
ister and DATA_SCALE field.
Sticky bit. This bit is reset by
POR. H_RESET, S_RESET, or
setting the STOP bit has no ef-
fect.
Description
Writing a 1 to this bit will clear it
If the function supports PME from
Read/write accessible always.
Data Scale. This two bit read-
Read only.
Read/write accessible always.