
IDT Hot-Plug and Hot-Swap
PES32NT24xG2 User Manual
11 - 5
January 30, 2013
Notes
The default value of fields in the PCIESCTL register following any reset other than a switch fundamental
reset (e.g., a partition fundamental reset, partition hot reset, partition upstream secondary bus, or partition
downstream secondary bus reset) is determined by the value of the corresponding field in the port’s PCI
Express Slot Control Initial Value (PCIESCTLIV) register when the corresponding hot-plug capability is
enabled.
The SLOT bit in the PCIECAP register and hot-plug capability bits in the PCIESCAP register are
SWSticky and, therefore, only get reset to their initial value due to a switch fundamental reset. This means
that the hot-plug capability is preserved across all types of partition resets. Following a partition reset, the
initial value of control fields in the PCIESCTL register are determined by the PCIESCTLIV register. For
example, if the SLOT bit set in the PCIECAP register and the PWRIP bit is set in the PCIESCAP register,
then the value of both fields will be preserved across any type of partition reset (i.e., since both of these
fields are of RWL type). This means that if the value of the PCC field in the PCIESCTLIV register is zero,
then the initial value of the corresponding field in the PCIESCTL register will be zero.
For fields in the PCIESCAP register that control hot-plug output signals, if the value of the field prior to
the occurrence of a partition reset is equal to the initial value of the field after a partition reset completes,
then the state of the hot-plug output signal is maintained and does not glitch. Continuing the example in the
above paragraph, if the PCC field was zero prior to a partition reset and the initial value of the PCC field is
zero following a partition fundamental reset, then the PxPEP hot-plug output remains asserted through the
partition fundamental reset and does not glitch.
Following a partition hot reset, a partition upstream secondary bus reset, or a downstream secondary
bus reset, each downstream switch port’s PHY will transition the link to the hot-reset state and subse-
quently re-train the link starting from the Detect state. When this occurs, the Hot-Plug controller for the port
does not set the Presence Detect Changed (PDC) bit in the PCIESSTS register.
Port Reset Outputs
Individual port reset outputs are provided via the PxRSTN hot-plug I/O expander output. Port reset
outputs may be configured to operate in one of two modes. These modes are Power Enable Controlled
Reset Output and Power Good Controlled Reset Output. The port reset output mode for all downstream
switch ports is determined by the Reset Mode (RSTMODE) field in the Hot-Plug Configuration Control
(HPCFGCTL) register.
In addition to a port reset output being asserted as determined by the Reset Mode (RSTMODE) field, a
port reset output is also asserted under the following circumstances.
–
When the partition with which the port is associated experiences a partition fundamental reset.
See section Partition Fundamental Reset on page 3-12 for more information on partition funda-
mental resets.
–
When the operating mode of a port is modified and the OMA field is set to reset. See section Reset
Mode Change Behavior on page 5-21 for more information on the actions that occur when the
OMA field is set to reset.
Hardware ensures that the minimum port reset output assertion pulse width is no less than 200 µ S.
Power Enable Controlled Reset Output
In this mode, a downstream switch port reset output state is controlled as a side effect of slot power
being turned on or off. The operation of this mode is illustrated in Figure 11.4. A downstream switch port’s
slot power is controlled by the Power Controller Control (PCC) bit in the PCI Express Slot Control
(PCIESCTL) register
Содержание PCI Express 89HPES32NT24xG2
Страница 20: ...IDT Table of Contents PES32NT24xG2 User Manual x January 30 2013 Notes...
Страница 24: ...IDT List of Tables PES32NT24xG2 User Manual xiv January 30 2013 Notes...
Страница 28: ...IDT List of Figures PES32NT24xG2 User Manual xviii January 30 2013 Notes...
Страница 56: ...IDT PES32NT24xG2 Device Overview PES32NT24xG2 User Manual 1 20 January 30 2013 Notes...
Страница 100: ...IDT Switch Core PES32NT24xG2 User Manual 4 22 January 30 2013 Notes...
Страница 124: ...IDT Switch Partition and Port Configuration PES32NT24xG2 User Manual 5 24 January 30 2013 Notes...
Страница 128: ...IDT Failover PES32NT24xG2 User Manual 6 4 January 30 2013 Notes...
Страница 148: ...IDT Link Operation PES32NT24xG2 User Manual 7 20 January 30 2013 Notes...
Страница 164: ...IDT SerDes PES32NT24xG2 User Manual 8 16 January 30 2013 Notes...
Страница 170: ...IDT Power Management PES32NT24xG2 User Manual 9 6 January 30 2013 Notes...
Страница 196: ...IDT Transparent Switch Operation PES32NT24xG2 User Manual 10 26 January 30 2013 Notes...
Страница 244: ...IDT SMBus Interfaces PES32NT24xG2 User Manual 12 40 January 30 2013 Notes...
Страница 247: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 3 January 30 2013 Notes...
Страница 248: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 4 January 30 2013 Notes...
Страница 330: ...IDT Switch Events PES32NT24xG2 User Manual 16 6 January 30 2013 Notes...
Страница 342: ...IDT Multicast PES32NT24xG2 User Manual 17 12 January 30 2013 Notes...
Страница 344: ...IDT Temperature Sensor PES32NT24xG2 User Manual 18 2 January 30 2013 Notes...
Страница 384: ...IDT Register Organization PES32NT24xG2 User Manual 19 40 January 30 2013...
Страница 492: ...IDT Proprietary Port Specific Registers PES32NT24xG2 User Manual 21 44 January 30 2013 Notes...
Страница 588: ...IDT NT Endpoint Registers PES32NT24xG2 User Manual 22 96 January 30 2013 Notes...
Страница 710: ...IDT JTAG Boundary Scan PES32NT24xG2 User Manual 25 12 January 30 2013 Notes...
Страница 743: ...IDT Usage Models PES32NT24xG2 User Manual 26 33 January 30 2013 Notes...
Страница 744: ...IDT Usage Models PES32NT24xG2 User Manual 26 34 January 30 2013 Notes...