ARM AMBA NIC-301 - Manual (Page 20)

Functional Description
ARM DDI 0397G Copyright © 2006-2010 ARM. All rights reserved. 2-5
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Combination 1
If you configure
INCR promotion and Early Write Response
and do not configure
allow broken
bursts
then the network converts all:
• AHB read fixed length bursts to AXI fixed length bursts.
• AHB write fixed length bursts with HPROT[3] asserted to AXI fixed length bursts:
—
All AHB write data beats receive an automatic OKAY response from the bridge
irrespective of the B-channel AXI response. This means that if the network receives
an error response, it does not feed it back to the master.
— The bridge can support up to five outstanding write accesses.
• Write fixed-length bursts with HPROT[3] negated to AXI fixed length bursts, and only
the last AHB write data beat receives the AXI buffered response for the complete AHB
transaction.
• AHB read INCR bursts with HPROT[3] asserted to AXI INCR4 bursts.
• Write INCR bursts with HPROT[3] asserted to AXI INCR4 bursts, and all AHB write
data beats receive an automatic OKAY response from the bridge, irrespective of the
B-channel AXI response. This means that if the network receives an error response, it
does not feed it back to the master.
• Read INCR bursts with HPROT[3] negated to a series of AXI singles.
• Write INCR bursts with HPROT[3] negated to a series of AXI singles, and each AHB
write beat is acknowledged with the AXI buffered write response.
Combination 2
If you configure
allow broken bursts
and do not configure
INCR promotion and Early Write
Response
, the network converts all:
• Read fixed length bursts with HPROT[3] asserted to AXI fixed length bursts.
• Read fixed length bursts with HPROT[3] negated to AXI singles.
• Write fixed length bursts with HPROT[3] asserted to AXI fixed length bursts, but only
the last AHB write data beat receives the AXI buffered response for the whole AHB
transaction. However, if the AHB burst is broken, then the network does not feed the AXI
response back to the master.
• Write fixed length bursts with HPROT[3] negated to AXI singles, and each AHB write
beat is acknowledged with the AXI buffered write response.
• Read INCR bursts to a series of AXI singles.
• Write INCR bursts to a series of AXI singles, and each AHB write beat is acknowledged
with the AXI buffered write response.
Combination 3
If you configure
INCR promotion and Early Write Response
and configure
allow broken bursts
then the network converts all:
• Read fixed length bursts with HPROT[3] asserted to AXI fixed length bursts.
• Read fixed length bursts with HPROT[3] negated to AXI singles.