IDT PCI to PCI Bridge and Proprietary Port Specific Registers
PES48T12G2 User Manual
15 - 69
April 5, 2013
Request Metering
RMCTL - Requester Metering Control (0x880)
RMCOUNT - Requester Metering Count (0x88C)
Bit
Field
Field
Name
Type
Default
Value
Description
0
EN
RW
0x0
SWSticky
Enable.
When this bit is set, request metering is enabled on the
corresponding input port. Refer to section Request Metering on
page 3-7.
4:1
OVRFACTOR
RW
0x2
SWSticky
Overhead Factor.
This field contains the overhead factor used in
computing the completion size estimate for memory read requests.
5
Reserved
RO
0x0
Reserved field.
15:6
CNSTLIMIT
RW
0x10
SWSticky
Constant Limit.
This field is used to control the algorithm used to
compute the completion size estimate for non-posted read
requests when request metering is enabled.
When the number of DWords required in completions to service a
non-posted read request is less than or equal to the value in this
field, then a constant completion size estimate is used.
When the number of DWords required in completions to service a
non-posted read request is greater than the value in this field, then
the completion size estimate considers the number of individual
completion TLPs.
31:16
DVADJ
RW
0x0
SWSticky
Decrement Value Adjustment.
This field contains the adjustment
value used to determine the value by which the request metering
counter is decremented each 250 MHz clock tick.
The value in this field represents a positive signed-magnitude,
fixed-point number with 4 integer bits and 11 fractional bits (i.e., a
0:4:11 format number). The most significant bit should always be
set to 0b0.
Bit
Field
Field
Name
Type
Default
Value
Description
15:0
COUNT
RO
0x0
Count.
This field contains the requester metering initial counter
value for the last non-posted request.
The request metering counter is a 24-bit counter that represents a
fixed point 0:13:11 number (i.e., an unsigned number with 13 inte-
ger bits and 11 fractional bits).
The value in this field represents an unsigned number with 13 inte-
ger bits and 3 fractional bits. The least significant eight fractional
bits of the initial counter value are always zero.
31:16
Reserved
RO
0x0
Reserved field.
Содержание 89HPES48T12G2
Страница 14: ...IDT Table of Contents PES48T12G2 User Manual vi April 5 2013 Notes...
Страница 22: ...IDT Register List PES48T12G2 User Manual xiv April 5 2013 Notes...
Страница 38: ...IDT PES48T12G2 Device Overview PES48T12G2 User Manual 1 16 April 5 2013 Notes...
Страница 64: ...IDT Reset and Initialization PES48T12G2 User Manual 5 8 April 5 2013 Notes...
Страница 82: ...IDT Link Operation PES48T12G2 User Manual 6 18 April 5 2013 Notes...
Страница 98: ...IDT SerDes PES48T12G2 User Manual 7 16 April 5 2013 Notes...
Страница 118: ...IDT Theory of Operation PES48T12G2 User Manual 8 20 April 5 2013 Notes...
Страница 152: ...IDT SMBus Interfaces PES48T12G2 User Manual 12 20 April 5 2013 Notes...
Страница 158: ...IDT Multicast PES48T12G2 User Manual 13 6 April 5 2013 Notes...