IDT Switch Operation
PES16NT2 User Manual
4 - 3
April 15, 2008
Notes
Each header credit is allocated 20 bytes (3 double doublewords) in a FIFO regardless of whether or not
a credit represents 16 or 20 bytes. Each posted and completion data credit is allocated 16 bytes (2 double
doublewords) in a FIFO. Non-posted data credits are allocated 8 bytes (one double doubleword). Two
header and data credits are reserved in each FIFO for TLPs generated by the switch (e.g., configuration
read completions).
The header and data flow control credits advertised may be configured on a per port basis via the Flow
Control Credit Posted Configuration (FCPTCFG), Flow Control Credit Non-Posted Configuration
(FCNPCFG) and Flow Control Credit Completion Configuration (FCCPCFG) registers. These registers may
only be modified using the serial EEPROM or during initialization via the SMBus when the RSTHALT bit is
set in the PA_SWCTL register. Modifying these registers in a running system produces undefined results.
Routing
The PES16NT2 supports routing of all transaction types defined in the PCIe specification. This includes
routing using in specification defined transactions as well as those that may be used in vendor defined
messages and in future revisions of the PCIe specifications.
Specifically, the PES16NT2 supports the following type of routing:
– Address routing with 32-bit or 64-bit format
– ID based routing using bus, device and function numbers.
– Implicit routing utilizing
Route to root
Broadcast from root
Local - terminate at receiver
Gathered and routed to root
– A summary of TLP types that use the above routing methods is provided in Table 4.3.
Non-Posted Data
30 credits
Each credit represents 16 bytes (i.e., 4 doublewords) for a max-
imum of 480 bytes (note that non-posted data is assumed to
consists of only one doubleword per header)
Completion Header
30 credits
Each credit represents 16 bytes (i.e., 4 doublewords) for a max-
imum of 480 bytes
Completion Data
204 credits
Each credit represents 16 bytes (i.e., 4 doublewords) for a max-
imum of 3264 bytes
Routing Method
TLP Type Using Routing Method
Route by Address
MRd, MrdLk, MWr, IORd, IOWr, Msg, MsgD
ID Based Routing
CfgRd0, CfgWr0, CfgRd1, CfgWr1, Cpl, CpdD, CplLk, CplDLk,
Msg, MsgD
Imlicit Routing - Route to Root
Msg, MsgD
Table 4.3 Switch Routing Methods
Flow Control
Category
Default
Advertised
Credits
Notes
Table 4.2 PES16NT2 Advertised Flow Control Credits
Содержание 89HPES16NT2
Страница 14: ...DT List of Figures PES16NT2 User Manual viii April 15 2008 Notes...
Страница 20: ...IDT Register List PES16NT2 User Manual xiv April 15 2008 Notes...
Страница 32: ...IDT PES16NT2 Device Overview PES16NT2 User Manual 1 12 April 15 2008 Notes...
Страница 44: ...IDT Clocking Reset and Initialization Clock Operation PES16NT2 User Manual 2 12 April 15 2008 Notes...
Страница 50: ...IDT Link Operation PES16NT2 User Manual 3 6 April 15 2008 Notes...
Страница 62: ...IDT Power Management PES16NT2 User Manual 5 4 April 15 2008 Notes...
Страница 78: ...IDT SMBus Interfaces PES16NT2 User Manual 6 16 April 15 2008 Notes...
Страница 83: ...IDT NTB Upstream Port Failover PES16NT2 User Manual 7 5 April 15 2008 Notes...
Страница 84: ...IDT NTB Upstream Port Failover PES16NT2 User Manual 7 6 April 15 2008 Notes...
Страница 130: ...IDT Transparent Mode Operation PES16NT2 User Manual 9 44 April 15 2008 Notes...
Страница 284: ...IDT Non Transparent Mode Operation PES16NT2 User Manual 10 154 April 15 2008 Notes...