2. RapidIO Ports > Hot Extraction/Insertion
CPS-1848 User Manual
42
June 2, 2014
Formal Status
This document is confidential and is subject to an NDA.
Integrated Device Technology
2.7.2
Port Disable/Enable
When a port is disabled and then enabled by setting and clearing
.PORT_DIS, the behavior of the
port is as described in
. The only difference is that packets are discarded for the entire period when PORT_DIS
is set.
2.7.3
Generating a Reset Request
The CPS-1848 can generate a reset request to its link partner by writing 0x0000_0003 to the
In some systems, it may be necessary to check that the link partner has acted on the reset request. This should be apparent
when the
Port {0..17} Error and Status CSR
PORT_OK bit is cleared, and the
Port {0..17} Error and Status CSR
PORT_UNINIT bit is asserted. Event notification can be configured to send a port-write or assert an interrupt when this occurs
(for more information, see
Once the link partner acts on the reset request,
.PORT_LOCKOUT should be asserted until the link
has retrained. This will cause all packets destined for the port to be discarded.
If the link partner accepts the reset, it will clear the expected and transmitted ackID values to 0. The
should be cleared to 0, and the CLR bit in this register should be set to 1. This will cause all outstanding unacknowledged
packets to be dropped.
Alternatively, the procedure for hot insertion can reset the link partner and discard all packets, as described in
2.8
Hot Extraction/Insertion
The hot extraction and insertion procedure is used to replace or upgrade hardware. It can also reset and then re-establish
communication with link partners, whether or not they have been physically replaced.
ackID resynchronization is required when PORT_DIS is set and cleared.
The procedure for ackID resynchronization is specific to the link partner device. If the link partner is a
CPS Gen2 device, resetting the link partner port and the local port will resynchronize the ackIDs (for
more information, see
A Link-Request/Input-Status control symbol should be sent to the link partner by writing to
[CMD] after a reset request followed by a link-response.
The following sections use the phrase “hot-swap link partner” (HS-LP) to identify the entity that is the
subject of the hot extraction/insertion or reset. The HS-LP can be the link partner of the CPS-1848, or
can be the CPS-1848 itself.
Hot Extraction/Insertion support requires exclusive use of the following registers. No Standard Physical
Layer Errors can be enabled when Hot Extraction/Insertion functionality is required.
•
Port {0..17} Error Report Enable Register
•
Lane {0..47} Error Report Enable Register
•
Port {0..17} Implementation Specific Error Rate Enable Register