Power management control/status (pmcsr) – LSI 53C875A User Manual

Page 108

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4-16

Registers

D2S

D2_Support

10

The LSI53C875A sets this bit to indicate support for
power management state D2.

D1S

D1_Support

9

The LSI53C875A sets this bit to indicate support for
power management state D1.

R

Reserved

[8:6]

DSI

Device Specific Initialization

5

This bit is cleared to indicate that the LSI53C875A
requires no special initialization before the generic class
device driver is able to use it.

APS

Auxiliary Power Source

4

Because the LSI53C875A does not provide a PME
signal, this bit is cleared, indicating that no auxiliary
power source is required to support the PME signal in the
D3cold power management state.

PMEC

PME Clock

3

Bit 3 is cleared because the LSI53C875A does not
provide a PME pin.

VER[2:0]

Version

[2:0]

These three bits are set to 010 to indicate that the
LSI53C875A complies with Revision 1.1 of the PCI Power
Management Interface Specification.

Registers: 0x44–0x45

Power Management Control/Status (PMCSR)
Read/Write

PST

PME Status

15

The LSI53C875A always returns a zero for this bit,
indicating that PME signal generation is not supported
from D3cold.

15

14 13 12

9

8

7

2

1

0

PST DSCL

DSLT

PEN

R

PWS[1:0]

0

0

0

0

0

0

0

0

x

x

x

x

x

x

0

0

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