IDT CPS-1848, User Manual

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6. Event Management > Event Isolation
CPS-1848 User Manual 154 June 2, 2014
Formal Status This document is confidential and is subject to an NDA.
Integrated Device Technology
6.4 Event Isolation
The RapidIO Error Management Extensions specify four standard event isolation behaviors when the physical layer error
counters reach the port failed threshold value (
Port {0..17} Error and Status CSR .OUTPUT_FAIL is set). The event isolation
behavior selected depends on the STOP_ON_PORT_FAIL_ENC_EN and DROP_PKT_EN fields in the Port {0..17} Control 1
CSR . The behaviors are described in Table 58 .
When a port detects an OUTPUT_FAIL condition and STOP_ON_PORT_FAIL_ENC_EN and DROP_PKT_EN are set, the port
(or device) must be reset to safely clear the OUTPUT_FAIL condition. One implication of this requirement is that when
STOP_ON_FAIL_ENC_EN and DROP_PKT_EN are set, the
Port {0..17} Error Rate CSR [ERR_RATE_BIAS] must be set to 0
to prevent the port from “healing” on its own.
Event isolation is in effect while Port {0..17} Error and Status CSR .PORT_FAIL is set.
The value of the physical layer counters does not affect the event isolation behavior when PORT_FAIL
is set. This behavior is not compliant to the RapidIO Specification (Rev. 2.1).
Table 58: Standard Event Isolation Behaviors
Bit Setting
Port Behavior
STOP_ON_PORT_FAIL
_ENC_EN
DROP_PKT_EN
0 0 The port continues to attempt to transmit packets to the connected device if the
Output Failed Encountered (OUTPUT_FAIL) bit is set in
Port {0..17} Error and Status
CSR and/or if the Error Rate Failed threshold has been met or exceeded in the Port
{0..17} Error Rate Threshold CSR .
0 1 The port discards packets that receive a Packet-not-accepted control symbol when
the Error Rate Failed Threshold has been met or exceeded. When a packet is
discarded, the port sets the Output Packet-dropped bit in the
Port {0..17} Error and
Status CSR . If the output port “heals”, the Error Rate Counter falls below the Error
Rate Failed Threshold and the output port continues to forward all packets.
1 0 The port stops attempting to send packets to the connected device when the Output
Failed Encountered (OUTPUT_FAIL) bit is set. The output port becomes congested.
1 1 The port discards all output packets without attempting to send them when the port’s
Output Failed Encountered (OUTPUT_FAIL) bit is set. When a packet is discarded,
the port sets the Output Packet-dropped (OUTPUT_DROP) bit in the
Port {0..17}
Error and Status CSR . If the output port “heals,” the Error Rate Counter may fall
below the Error Rate Failed Threshold. However, contrary to the
RapidIO Specification (Rev. 2.1), the port will continue to discard packets until this
state is cleared, as described in
Clearing and Handling Port Fail and Port Degraded
Events .
When STOP_ON_PORT_FAIL_ENC_EN and DROP_PKT_EN are set, only events which indicate that
the link partner has been removed can be used to detect an OUTPUT_FAIL condition. These events
are restricted to those documented in
Hot Extraction/Insertion . Use of any other events requires a
device reset to recover the CPS-1848 after an OUTPUT_FAIL condition is detected. For more
information on device resets, see
Resets after Power-Up .