*Notice: The information in this document is subject to change without notice
Tsi301
Notes
Tsi301 HyperTransport to PCI User Manual
5-36
Read Control
Offset 62h–60h
Bits
Type
Reset
Description
23:22
RW
000b
Reserved.
21:19
RW
000b
Line Prefetch Initial Count - indicates the minimum number of lines that must be
successfully prefetched from memory on a MemRdLine (or MemRd if prefetch-
ing is enabled for MemRd commands) before allowing the PCI requester to
reconnect. Not persistent through warm reset.
18:16
RW
000b
Multiple Prefetch Intitial Count - indicates the minimum number of lines that
must be successfully prefetched from memory on a MemRdMult before allow-
ing the PCI requester to reconnect. Not persistent through warm reset.
15:12
RW
0h
Reserved.
11
RW
0
Line Prefetch Continue - if set, and prefetching for MemRdLine commands is
enabled, MemRdLine (and MemRd, if prefetching is enabled for MemRd com-
mands) prefetching will be continuous. As each line of data is returned to PCI,
another line will be read from HyperTransport, creating a moving prefetch win-
dow. Otherwise, prefetching will end when the specified number of lines has
been fetched. Not persistent through warm reset.
10
RW
0
MultPrefetchContinue - if set, and prefetching for MemRdMult commands is
enabled, MemRdMult prefetching will be continuous. As each line of data is
returned to PCI, another line is read from HyperTransport, creating a moving
prefetch window. Otherwise, prefetching will end when the specified number of
lines has been fetched. Not persistent through warm reset.
9:8
RW
00b
PCI Delayed Requests - this controls the number of PCI delayed requests that
may be outstanding at one time. The value in the register plus 1 is the number
that will be allowed, enabling from one to four buffers. Not persistent through
warm reset.
7:5
RW
000b
Line Prefetch Count - this indicates the number of lines to be prefetched for
MemRdLine commands, and MemRd commands if prefetching is enabled for
them, in addition to the line containing the original request address. MemRd-
Line (and MemRd, if enabled) always prefetch at least to the end of the first line.
This field may not be set to a larger value than Multiple Prefetch Count. Not per-
sistent through warm reset.
4:2
RW
000b
Multiple Prefetch Count - this indicates the number of lines to be prefetched for
MemRdMult commands, in addition to the line containing the original request
address. MemRdMults always prefetch at least to the end of the first line. Not
persistent through warm reset.
1
RW
0
Mem Rd Prefetch Enable - if set, PCI MemRd commands are treated as
prefetchable using the same prefetch controls as for memRdLine. Otherwise,
no prefetching is performed for MemRds, and they fetch only the initially
requested DW or QW. Not persistent through warm reset.
0
RW
0
Prefetch Enable - this bit enables prefetching for prefetchable read requests. If
clear, no prefetching of any kind is performed. Not persistent through warm
reset.