10. Registers > Global Device Configuration Registers
CPS-1848 User Manual
363
June 2, 2014
Formal Status
This document is confidential and is subject to an NDA.
Integrated Device Technology
10.14.14 Switch Parameters 1 Register
Register Name: SWITCH_PARAM_1
Reset Value: 0x000C_0C9F
Register Offset: 0xF20068
Bits
0
1
2
3
4
5
6
7
00:07
Reserved
08:15
Reserved
FB_ALLOC
BUF_ALLO
C
ARB_MODE
16:23
ARB_MODE
OUTPUT_CREDIT_RSVN
24:31
OUTPUT_CREDIT_RSVN
INPUT_STARV_LIM
Bits
Name
Description
Type
Reset
Value
0:10
Reserved
Reserved
RO
0
11:13
FB_ALLOC
Final Buffer Allocation Size
This field reserves buffer space for higher priorities. It is ignored if
BUF_ALLOC is configured for single buffer allocation mode.
Highest priority packets can use all the buffers if they arrive first
(no need to reserve for lower priority). However, if lower priority
packet arrive first, they cannot use all the buffers if there are no
higher priority packets that are currently in the buffer. Instead, the
reserved buffer guarantees that higher priority packets can be
handled if they arrive at a later time.
000–001 = Reserved
010 = 2 buffers reserved for each VC0 priority 1, 2, and 3
011 = 3 buffers reserved for each VC0 priority 1, 2, and 3
100 = 4 buffers reserved for each VC0 priority 1, 2, and 3
101 = 5 buffers reserved for each VC0 priority 1, 2, and 3
110 = 6 buffers reserved for each VC0 priority 1, 2, and 3
111 = 7 buffers reserved for each VC0 priority 1, 2, and 3
RW
0b011
14
BUF_ALLOC
Buffer Allocation Mode
0 = Multi-buffer reservation mode.
Minimum of two pages are allocated to each priority (1, 2, 3) in
input and crosspoint buffers.
1 = Single buffer reservation mode.
Minimum of one page is allocated to each priority (1, 2, 3) in
input, crosspoint and final buffers.
RW
0