IDT 89HPES16NT2, User Manual

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IDT Transparent Mode Operation
PES16NT2 User Manual 9 - 23 April 15, 2008
Notes PA_PCIELCTL - PCI Express Link Control (0x050)
PA_PCIELSTS - PCI Express Link Status (0x052)
Bit
Field
Field
Name
Type
Default
Value
Description
1:0 ASPM RW 0x0 Active State Power Management (ASPM) Control . This
field controls the level of ASPM supported by the link. The
initial value corresponds to disabled. The value contained
in Serial EEPROM may override this default value
0x0 - (disabled) disabled
0x1 - (l0s) L0s enable entry
0x2 - (l1) L1 enable entry
0x3 - (l0sl1) L0s and L1 enable entry
2 Reserved RO 0x0 Reserved field.
3 RCB RO 0x0 Read Completion Boundary . This field is not applicable
and is hardwired to zero.
4 LDIS RW 0x0 Link Disable. When set, this bit disables the link. This field
is hardwired to 0x0 for the upstream port.
5 LRET RW 0x0 Link Retrain . Writing a one to this field initiates Link
retraining by directing the Physical Layer LTSSM to the
Recovery state. This field always returns zero when read.
For compliance with the PCIe specification, this bit has no
effect on the upstream port when the REGUNLOCK bit is
cleared in the PA_SWCTL register. When the REGUN-
LOCK bit is set, writing a one to the LRET bit initiates link
retraining on the upstream port.
6 CCLK RW 0x0 Common Clock Configuration . When set, this bit indi-
cates that this component and the component at the oppo-
site end of the link are operating with a distributed common
reference clock.
7 ESYNC RW 0x0 Extended Sync . When set this bit forces transmission of
4096 FTS ordered sets in the L0s state followed by a single
SKP ordered set.
15:8 Reserved RO 0x0 Reserved field.
Bit
Field
Field
Name
Type
Default
Value
Description
3:0 LS RO 0x1 Link Speed . This field is hardwired to 2.5 Gbps.
9:4 LW ROS HWINIT Link Width . This field indicates the negotiated width of the
link.
10 TERR ROS 0x0 Training Error. When set, this bit indicates that a link train-
ing error has occurred.
11 LTRAIN ROS 0x0 Link Training . When set, this bit indicates that link training
is in progress.