Altera RapidIO MegaCore Function - Manual (Page 110)

4–64 Chapter 4: Functional Description
Error Detection and Management
RapidIO MegaCore Function August 2014 Altera Corporation
User Guide
■ Unsolicited Response is declared when a response is received that does not
correspond to any pending MAINTENANCE read or write request.
■ Packet Response Timeout is declared when a response is not received within the
time specified by the Port Response Time-Out CSR ( Table 6–7 on page 6–6 ) for a
pending MAINTENANCE read or write request.
■ Illegal Transaction Decode is declared for malformed received response packets
occurring from any of the following events:
■ Response packet to pending MAINTENANCE read or write request with status not
DONE
nor ERROR.
■ Response packet with payload with a transaction type different from
MAINTENANCE
read response.
■ Response packet without payload, with a transaction type different from
MAINTENANCE
write response.
■ Response to a pending MAINTENANCE read request with more than 32 bits of
payload. (The RapidIO IP core issues only 32-bit read requests.)
Registers in the Implementation Defined Space
The Maintenance register module defines the Maintenance Interrupt register
(
Table 6–26 on page 6–16 ) in which the following two bits report Maintenance
Avalon-MM slave related error conditions:
■ WRITE_OUT_OF_BOUNDS
■ READ_OUT_OF_BOUNDS
These bits are set when the address of a write or read transfer on the Maintenance
Avalon-MM slave interface falls outside of all the enabled address mapping windows.
When these bits are set, the system interrupt signal sys_mnt_s_irq is also asserted if
the corresponding bit in the Maintenance Interrupt Enable register (
Table 6–27 on
page 6–17 ) is set.
Maintenance Avalon-MM Slave Interface's Error Indication Signal
The mnt_s_readerror output is asserted when a response with ERROR status is
received for a MAINTENANCE read request packet, when a MAINTENANCE read times out,
or when the Avalon-MM read address falls outside of all the enabled address
mapping windows.
Maintenance Avalon-MM Master
The Maintenance Avalon-MM master module processes the MAINTENANCE read and
write request packets that it receives and generates response packets. Anomalies are
reported by generating ERROR response packets. A response packet with ERROR status
is generated in the following cases:
■ Received a MAINTENANCE write request packet without payload or with more than
64 bytes of payload
■ Received a MAINTENANCE read request packet of the wrong size (too large or too
small)
■ Received a MAINTENANCE read or write request packet with an invalid rdsize or
wrsize
value