IDT CPS-1848, User Manual

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6. Event Management > Event Clearing and Recovery
CPS-1848 User Manual 165 June 2, 2014
Formal Status This document is confidential and is subject to an NDA.
Integrated Device Technology
6.5.2.1 Loss of AckID Synchronization
Each S-RIO port supports the software-assisted error recovery registers defined in the RapidIO Specification (Rev. 2.1). These
registers include the
Port {0..17} Link Maintenance Request CSR , the Port {0..17} Link Maintenance Response CSR , and the
Port {0..17} Local ackID CSR . A set of each of these three registers are provided per S-RIO port. Their use is described in
subsequent sections.
Additionally, if the link partner supports a per-port reset function, it may be possible to cleanly recover from loss of ackID sync
by resetting the link partner (for more information, see
Reset Control Symbol Processing ).
6.5.2.1.1 Usage Definition for Port {0..17} Link Maintenance Request CSR
A write to this register forces the S-RIO port to transmit a Link-Request symbol on the associated link. The command field in
the transmitted symbol are the contents of the CMD field written into this register. A read of this register returns the value of the
CMD field in the register.
Support is provided for the following CMD field values:
• 0b011 = Reset device
• 0b100 = Input status
6.5.2.1.2 Port {0..17} Link Maintenance Request CSR (Reset Command Field)
When a write to this register is received with the CMD field set to 0b011 (reset device) the device will:
• Cease all current and pending transmissions (data and S-RIO control symbols – including multicast control symbols)
• Transmit four Link-Request – Reset Symbols in succession. After transmitting the Link-Request - Reset Symbols, the port
will enter the output error state and wait for a corresponding Link-Response.
6.5.2.1.3 Usage Definition for Port {0..17} Link Maintenance Response CSR
This register is read-only and contains the information contained in the most recently received Link-Response by the specific
port. When read, it returns this data.
Bad control character sequence Port {0..17} Implementation
Specific Error Detect
Register
.BAD_CTL = 0, then
Port {0..17} Error Detect
CSR
.IMP_SPEC_ERR = 0
Transmission error - hardware error recovery
Lanes reordered Port {0..17} Implementation
Specific Error Detect
Register
.REORDER = 0, then
Port {0..17} Error Detect
CSR
.IMP_SPEC_ERR = 0
May be expected on some boards due to lane connections
between devices.
Table 61: Physical Layer Events and Information Capture Summary (Continued)
Event Clearing The Event Event Handling Discussion