580 AMD Geode™ LX Processors Data Book
GeodeLink™ PCI Bridge Register Descriptions
33234H
24 MARS Master Abort Receive ASMI. Allow reception of a PCI bus master abort to be reported
in the TARE bit (MSR 50002002h[17]).
0: Disable.
1: Enable.
23:21 SUS Busy Sustain. Controls the sustain time for keeping the clocks running after the internal
busy signals indicate that the clocks may be gated.
000: No sustain 100: 32 clock cycles
001: 4 clock cycles 101: 64 clock cycles
010: 8 clock cycles 110: 128 clock cycles
011: 16 clock cycles 111: 256 clock cycles
20:18 IRFT In-Bound Read Flush Timeout. Controls the flushing of in-bound prefetch read data.
When an in-bound read has completed on the PCI bus, an internal counter is loaded with
a value derived from this field. It then counts down on each PCI clock edge. When the
counter reaches 0, any remaining prefetched data is flushed. The counter stops counting
down if a subsequent in-bound read is received. It continues to count down through an
in-bound write and through any out-bound traffic.
000: 4 PCI clock edge 100: 64 PCI clock edges
001: 8 PCI clock edges 101: 128 PCI clock edges
010: 16 PCI clock edges 110: 256 PCI clock edges
011: 32 PCI clock edges 111: No timeout
17:16 IRFC In-Bound Read Flush Control. Controls the policy for discarding stale data from in-
bound read data FIFO.
00: Discard at end of in-bound read PCI transaction.
01: Discard upon timeout.
10: Discard at start of out-bound write or upon timeout.
11: Discard at start of out-bound write, at start of out-bound read or upon timeout.
In addition to these policies, in-bound read data will be discarded whenever a non-contig-
uous in-bound read is accepted, or when an in-bound write is received that will affect the
prefetched memory.
15:13 IOD I/O Delay. Delay completion of out-bound I/O transactions for a configurable number of
PCI clock cycles.
000: 0 PCI clock cycles
001: 1 PCI clock cycles
010: 2 PCI clock cycles
011: 4 PCI clock cycles
100: 8 PCI clock cycles
101: 16 PCI clock cycles
110: 32 PCI clock cycles
111: 64 PCI clock cycles
12 ST Short Timer. When cleared to 0, delayed transactions are discarded after 215 PCI clock
cycles. When set to 1, delayed transactions are discarded after 25 PCI clock cycles. For
normal operation. this bit should be cleared.
11 ER Early Read. When cleared to 0, out-bound reads are stalled until there is enough FIFO
space in the out-bound read FIFO to hold data for the entire transaction. When set to 1,
out-bound reads will start as soon as possible.
10 RHE Read Hints Enable. When cleared to 0, all out-bound reads use PCI CMD = 6. When set
to 1, the PCI CMD provides a hint about the size of the read request.
6: 1, 2 or 4 DWORDs
E: 8 DWORDs
GLPCI_CTRL Bit Descriptions (Continued)
Bit Name Description