3.1.3. AHB restrictions

Using a multilayer AHB system requires that certain restrictions are placed on the use of locked transfers to prevent a deadlock situation. A sequence of locked transfers must all be performed to the same slave in the system. A bus master can ensure this restriction is met by ensuring that a locked sequence of transfers remains inside a 1KB address region.

Specifically, if a bus master is to perform two locked transfer sequences to different address regions, the bus master must not start the second locked transfer sequence until the final data phase of the first locked transfer sequence has completed.

Copyright © 2004, 2006 ARM Limited. All rights reserved.ARM DDI 0287B
Non-Confidential