14. Register Descriptions > Register Map
152
PEB383 User Manual
July 25, 2011
Integrated Device Technology, Inc.
Confidential - NDA Required
14.3.17
Upstream Posted Write Threshold Register
Register name: UPST_PWR_THRES
Reset value: 0x0000_0307
Register offset: 0x04C
Bits
7
6
5
4
3
2
1
0
31:24
Reserved
23:16
Reserved
15:8
Reserved
MAX_BUF_ALOC
7:0
Reserved
UPST_PWR_THRES
Bits
Name
Description
Type
Reset value
31:10
Reserved
Reserved.
R
0
9:8
MAX_BUF_ALOC
Maximum Buffer Allocation
This field determines the maximum completion buffer
allocation that a single, upstream non-posted read
request will create.The amount of completion buffer
allocated is the MIN of these bits and the read request.
11 = 1024 bytes
10 = 512 bytes
01 = 256 bytes
00 = 256 bytes
R/W
11
7:5
Reserved
Reserved.
R
0
4:0
UPST_PWR_THRES
This field defines the threshold for the upstream posted
writes, and indicates the length of posted write data to
be accumulated in the upstream posted buffer that
triggers forwarding of a posted request onto the PCIe
core.
Note: Other events may also trigger forwarding. For
more information, see
This field is defined as follows:
00000 = 16 bytes
00001 = 32 bytes
00010 = 48 bytes
00011 = 64 bytes
00100 = 80 bytes
00101 = 96 bytes
00110 = 112 bytes
00111 = 128 bytes
R/W
00111