IDT 89HPES16T4AG2, User Manual

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IDT Configuration Registers
PES16T4AG2 User Manual 8 - 50 May 23, 2013
Notes PVCCAP2- Port VC Capability 2 (0x208)
PVCCTL - Port VC Control (0x20C)
PVCSTS - Port VC Status (0x20E)
Bit
Field
Field
Name
Type
Default
Value
Description
7:0 VCARBCAP RO 0x0 VC Arbitration Capability. This field indicates the type of VC
arbitration that is supported by the port for the low priority VC
group.
This field is valid for all ports that report a low priority extended
VC count greater than zero.
Each bit in this field corresponds to a VC arbitration capability.
bit 0 - hardware fixed arbitration (i.e., round robin)
bit 1 - weighted round robin (WRR) with 32 phases
bit 2 - weighted round robin (WRR) with 64 phases
bit 3 - weighted round robin (WRR) with 128 phases
bits 4 through 7 - reserved
23:8 Reserved RO 0x0 Reserved field.
31:24 VCATBLOFF RO 0x0 VC Arbitration Table Offset. This field contains the offset of the
VC arbitration table from the base address of the Virtual Channel
Capability structure in double quad words (16 bytes).
The value of zero indicates that the VC arbitration table is not
present.
Bit
Field
Field
Name
Type
Default
Value
Description
0 LVCAT RO 0x0 Load VC Arbitration Table. This bit, when set, updates the VC
arbitration logic from the VC Arbitration Table for the VC
resource.
Since the device does not implement a VC arbitration table, this
field has no functional effect.
This bit always returns 0 when read.
3:1 VCARBSEL RW 0x0 VC Arbitration Select. This field configures the VC arbitration by
selecting one of the supported arbitration schemes indicated by
the VC arbitration capability field (i.e., the VCARBCAP field in the
PVCCAP2 register).
Since the device supports only VC0, this field has no functional
effect.
15:4 Reserved RO 0x0 Reserved field.
Bit
Field
Field
Name
Type
Default
Value
Description
0 VCATS RO 0x0 VC Arbitration Table Status. This bit indicates the coherency
status of the VC arbitration table.
Since the device supports only VC0, this field has no functional
effect and is always zero.
15:1 Reserved RO 0x0 Reserved field.