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Chapter 4: Parameter Settings
4–7
PCI Express and PCI Capabilities Parameters
June 2012
Altera Corporation
Stratix V Hard IP for PCI Express
Completion timeout
range
ABCD
BCD
ABC
AB
B
A
None
ABCD
Indicates device function support for the optional completion
timeout programmability mechanism. This mechanism allows
system software to modify the completion timeout value. This field
is applicable only to Root Ports and Endpoints that issue requests
on their own behalf. Completion timeouts are specified and enabled
in the Device Control 2 register (0x0A8) of the PCI Express
Capability Structure Version 2.0 described in
. For all other functions this field is reserved and must be
hardwired to 0x0000b. Four time value ranges are defined:
■
Range A: 50 us to 10 ms
■
Range B: 10 ms to 250 ms
■
Range C: 250 ms to 4 s
■
Range D: 4 s to 64 s
Bits are set to show timeout value ranges supported. The function
must implement a timeout value in the range 50 s to 50 ms. The
following values are used to specify the range:
■
None – Completion timeout programming is not supported
■
0001 Range A
■
0010 Range B
■
0011 Ranges A and B
■
0110 Ranges B and C
■
0111 Ranges A, B, and C
■
1110 Ranges B, C and D
■
1111 Ranges A, B, C, and D
All other values are reserved. Altera recommends that the
completion timeout mechanism expire in no less than 10 ms.
Implement
completion timeout
disable
On/Off
On
For Endpoints using PCI Express version 2.0, this option must be
On
. The timeout range is selectable. When
On
, the core supports
the completion timeout disable mechanism via the PCI Express
Device Control Register 2
. The Application Layer logic must
implement the actual completion timeout mechanism for the
required ranges.
Table 4–6. Capabilities Registers (Part 2 of 2)
Parameter
Possible
Values
Default Value
Description