8.11.1. Breakpoint with prefetch abort

When a breakpointed instruction fetch causes a prefetch abort, the abort is taken and the breakpoint is disregarded. Normally, prefetch aborts occur when, for example, an access is made to a virtual address which does not physically exist, and the returned data is therefore invalid.

In such a case, the operating system’s normal action is to swap in the page of memory and return to the previously invalid address. Here, when the instruction is fetched, and providing the breakpoint is activated (it may be data-dependent), ARM7DMT enters debug state.

In this case, the prefetch abort takes higher priority than the breakpoint.

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