4.3.  AHB Slave Capabilities

It is worth noting at this point that the L2CC performs different types of accesses than the connected ARM processor core under some conditions, including extensive use of the BUSY transfer type and INCR burst types. In order for your existing slaves to work with the L2CC they must support the full AHB 2 specification.

The L2CC will produce BUSY transfer types when it needs to hold off the master from producing any further access so that the response from the slave can be correctly asserted to the master in time for the address that caused it.

There is no way of removing these BUSY transfers since if they are removed then any ERROR being returned from the slave would not be back to the master in time to indicate the ERROR to the correct address. The result of this would produce software errors (where the software is being told by the system that a particular address caused an error, when in fact it was a different address).

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