
4–30 Chapter 4: Functional Description
Logical Layer Modules
RapidIO MegaCore Function August 2014 Altera Corporation
User Guide
■
config_offset
is generated by using the values programmed in the
Tx
Maintenance
Address
Translation
Window
registers, as described in Table 6–28
through Table 6–35.
■
wdptr
Each window is enabled if the window enable (
WEN
) bit of the
Tx Maintenance
Window
n
Mask
register (Table 6–30 on page 6–18) is set. Each window is defined by the
following registers:
■ A base register:
Tx
Maintenance
Mapping
Window
n
Base
(Table 6–29 on page 6–18)
■ A mask register:
Tx
Maintenance
Mapping
Window
n
Mask
(Table 6–30)
■ An offset register:
Tx
Maintenance
Mapping
Window
n
Offset
(Table 6–31)
■ A control register:
Tx
Maintenance
Mapping
Window
n
Control
(Table 6–32)
For each defined and enabled window, the Avalon-MM address's least significant bits
are masked out by the window mask and the resulting address is compared to the
window base. If the addresses match,
config_offset
is created based on the
following equation:
If
(mnt_s_address[23:1]
&
mask[25:3])
==
base[25:3]
then
config_offset
=
(offset[23:3]
&
mask[23:3])
|
(mnt_s_address[21:1]
&
~mask
[23:3])
where:
■
mnt_s_address[23:0]
is the Avalon-MM slave interface address
■
config_offset[20:0]
is the outgoing RapidIO register double-word offset
■
base[31:0]
is the base address register
■
mask[31:0]
is the mask register
■
offset[23:0]
is the window offset register
If the address matches multiple windows, the lowest number window register set is
used.
The following fields are inserted from the control register of the mapping window
that matches.
■
prio
■
dest_id
■
hop_count
The
tt
value is determined by your selection of device ID width at the time you create
this RapidIO IP core variation. The
source_tid
is generated internally and the
wdptr
is assigned the negation of
mnt_s_address[0]
.
For a
MAINTENANCE
Avalon-MM slave write, the value on the
mnt_s_writedata[31:0]
bus is inserted in the
payload
field of the
MAINTENANCE
write packet.
Maintenance Master Processor
This module performs the following tasks:
■ For a
MAINTENANCE
read, converts the received request packet to an Avalon read
and presents it across the Maintenance Avalon-MM master interface.
Komentáře k této Příručce