PI7C9X110 Pericom Semiconductor Corporation, PI7C9X110 Datasheet - Page 42

• Manufacturer Part Number: PI7C9X110
• Description: Pcie-to-pci Reversible Bridge
• Manufacturer: Pericom Semiconductor Corporation

7.4.31 PCI DATA BUFFERING CONTROL REGISTER – OFFSET 40h
Pericom Semiconductor
BIT
24
25
26
27
31:28
BIT
0
1
2
3
5:4
FUNCTION
Primary Master Timeout
Secondary Master Timeout
Master Timeout Status
Discard Timer SERR_L
Enable
Reserved
FUNCTION
Secondary Internal Arbiter’s
PARK Function
Memory Read Prefetching
Dynamic Control Disable
Completion Data Prediction
Control
Reserved
PCI Read Multiple Prefetch
Mode
TYPE
TYPE
RWC
RW
RW
RW
RW
RW
RW
RW
RO
RO
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DESCRIPTION
0: Primary discard timer counts 2
1: Primary discard timer counts 2
FORWARD BRIDGE –
Bit is RO and ignored by the PI7C9X110
Reset to 0
0: Secondary discard timer counts 2
1: Secondary discard timer counts 2
REVERSE BRIDGE –
Bit is RO and ignored by PI7C9X110
Reset to 0
Bit is set when the discard timer expires and a delayed completion is
discarded at the PCI interface for the forward or reverse bridge
Reset to 0
Bit is set to enable to generate ERR_NONFATAL or ERR_FATAL for
forward bridge, or assert P_SERR_L for reverse bridge as a result of the
expiration of the discard timer on the PCI interface.
Reset to 0
Reset to 0000
DESCRIPTION
0: Park to the last master
1: Park to PI7C9X110 secondary port
Reset to 0
0: Enable memory read prefetching dynamic control for PCI to PCIe read
1: Disable memory read prefetching dynamic control for PCI to PCIe read
Reset to 0
0: Enable completion data prediction for PCI to PCIe read.
1: Disable completion data prediction
Reset to 0
Reset to 0
These two bits are ignored in PCI-X mode.
00: One cache line prefetch if memory read multiple address is in
prefetchable range at the PCI interface
01: Full prefetch if address is in prefetchable range at PCI interface, and the
PI7C9X110 will keep remaining data after it disconnects the external master
during burst read with read multiple command until the discard timer expires
10: Full prefetch if address is in prefetchable range at PCI interface
11: Full prefetch if address is in prefetchable range at PCI interface and the
PI7C9X110 will keep remaining data after the read multiple is terminated
either by an external master or by the PI7C9X110, until the discard time
expires
Reset to 10
15
10
PCI clock cycles
PCI clock cycles
15
10
PCI clock cycles
PCI clock cycles
May 2008, Revision 2.6
PCIe-to-PCI Reversible Bridge
PI7C9X110