GR740-UM-DS, Nov 2017, Version 1.7
421
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GR740
Table 551.
GRSPW hardware RMAP handling of different packet type and command fields.
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Command
Action
Reserved
Command
/ Response
Write /
Read
Verify
data
before
write
Acknow-
ledge
Increment
Address
0
0
-
-
-
-
Response
Stored to DMA-channel.
0
1
0
0
0
0
Not used
Does nothing. No reply is sent.
0
1
0
0
0
1
Not used
Does nothing. No reply is sent.
0
1
0
0
1
0
Read single
address
Executed normally. Address has
to be word aligned and data size
a multiple of four. Reply is sent.
If alignment restrictions are vio-
lated error code is set to 10.
0
1
0
0
1
1
Read incre-
menting
address.
Executed normally. No restric-
tions. Reply is sent.
0
1
0
1
0
0
Not used
Does nothing. No reply is sent.
0
1
0
1
0
1
Not used
Does nothing. No reply is sent.
0
1
0
1
1
0
Not used
Does nothing. Reply is sent with
error code 2.
0
1
0
1
1
1
Read-Mod-
ify-Write
increment-
ing address
Executed normally. If length is
not one of the allowed rmw val-
ues nothing is done and error
code is set to 11. If the length
was correct, alignment restric-
tions are checked next. 1 byte
can be rmw to any address. 2
bytes must be halfword aligned.
3 bytes are not allowed. 4 bytes
must be word aligned. If these
restrictions are violated nothing
is done and error code is set to
10. If an AHB error occurs error
code is set to 1. Reply is sent.
0
1
1
0
0
0
Write, sin-
gle-address,
do not verify
before writ-
ing, no
acknowledge
Executed normally. Address has
to be word aligned and data size
a multiple of four. If alignment is
violated nothing is done. No
reply is sent.
0
1
1
0
0
1
Write, incre-
menting
address, do
not verify
before writ-
ing, no
acknowledge
Executed normally. No restric-
tions. No reply is sent.
0
1
1
0
1
0
Write, sin-
gle-address,
do not verify
before writ-
ing, send
acknowledge
Executed normally. Address has
to be word aligned and data size
a multiple of four. If alignment is
violated nothing is done and
error code is set to 10. If an AHB
error occurs error code is set to 1.
Reply is sent.