Altera RapidIO MegaCore Function - Manual (Page 43)

Chapter 3: Parameter Settings 3–7
I/O and Doorbell Settings
August 2014 Altera Corporation RapidIO MegaCore Function
User Guide
This parameter is not available for variations that target an Arria 10 device. RapidIO
IP core Arria 10 variations that include an I/O Logical layer Avalon-MM slave
module preserve transaction ordering between read and write operations in the I/O
Avalon-MM Logical layer slave module.
Whether you turn on this feature or not, as required by the Avalon-MM specification,
each individual Logical layer Avalon-MM slave module preserves response order.
Even if the responses to two requests from the same Logical layer Avalon-MM slave
module arrive in reverse order on the RapidIO link, the Logical layer module enforces
the response order on the Avalon-MM interface. The slave module enforces the order
by maintaining a queue of the Transaction IDs of transactions awaiting responses
from the RapidIO link.
For more information about the I/O read and write order preservation feature, refer
to
“Input/Output Avalon-MM Slave Module” on page 4–41 .
Avalon-MM Master
Number of Rx address translation windows is only applicable if you select an I/O
Avalon-MM master as an I/O Logical layer interface. You can specify a value from 1
to 16.
This parameter is not available for variations that target an Arria 10 device. RapidIO
IP core Arria 10 variations that include I/O Logical layer master module have 16 Rx
address translation windows.
Avalon-MM Slave
Number of Tx address translation windows is only applicable if you select an I/O
Avalon-MM slave as an I/O Logical layer interface. You can specify a value from 1 to
16
.
This parameter is not available for variations that target an Arria 10 device. RapidIO
IP core Arria 10 variations that include I/O Logical layer slave module have 16 Tx
address translation windows.
Doorbell Slave
Doorbell Tx enable controls support for the generation of outbound DOORBELL
messages.
Doorbell Rx enable controls support for the processing of inbound DOORBELL
messages. If not enabled, received DOORBELL messages are routed to the Avalon-ST
pass-through interface if it is enabled, or are silently dropped if the pass-through
interface is not enabled.
These parameters are linked for variations that target an Arria 10 device. RapidIO IP
core Arria 10 variations either support outbound and inbound DOORBELL messages, or
do not support DOORBELL messages. If you turn on one of these options, you must turn
on both.
Prevent doorbell messages from passing write transactions controls support for
preserving transaction order between DOORBELL messages and I/O write request
transactions. This option is available only if you turn on Doorbell Tx enable and set
I/O logical layer Interfaces
to Avalon-MM Master and Slave or Avalon-MM Slave.