When you connect to a target you might see warning messages of the form:

Warning: Overlapping un-controlled memory region 'region_1' and 'region_2'

Also, this message is accompanied by one or more instances of the following message:

Warning: Memory map overlaps with existing mapping(s).

These messages are displayed for the following reasons:

Memory areas are uncontrolled when they are not associated with a memory map rule. This is the default configuration. If you have defined multiple memory areas that occupy the same area of memory, but only one is to be active at a time, then the memory areas must be controlled using map rules.

Uncontrolled memory map areas that overlap is not usually a problem if one BCD file defines a generic memory region, and another defines one or more specific memory regions. RealView Debugger creates a combined memory region by overlaying the generic region with the specific memory regions.

Example

With the CM926EJ-S.bcd file and the CP.bcd file assigned to a Debug Configuration, warning messages similar to the following are displayed when you connect to an ARM926EJ-S target:

Warning: Overlapping un-controlled memory region 'M_REGS (I/O Registers)' and 'M_CM_Regs (CM Registers)'

In this example, Figure 4.40 shows the memory map for the ARM926EJ-S target.

Figure 4.40. Memory map defined in the CM926EJ-S.bcd file

Figure 4.41 shows the combined memory from both the CM926EJ-S.bcd file and the CP.bcd file.

Figure 4.41. Combined memory map for CM926EJ-S.bcd and CP.bcd

In Figure 4.41 you see that the memory regions CPU Int.Ctrl and SDRAM SPDMEM from the CP.bcd file overlay the CM Registers memory region from the CM926EJ-S.bcd file.