6.4 About address spaces

You can use address space prefixes in DS-5 Debugger to refer to different addresses spaces. You can use these address space prefixes for various debugging activities such as to:
  • set breakpoint in a specific memory space
  • read or write memory
  • load symbols associated with a specific memory space.
DS-5 Debugger also uses these prefixes when reporting the current memory space where the execution stopped.

Note

The address spaces can be different on different targets. The availability of an address space depends on what architecture features are implemented, such as security extensions.

Address spaces in ARMv7 based processors

The following address space prefixes might be available for ARMv7 based processors:
  • S: This corresponds to the secure address space.
  • H: This corresponds to the hypervisor address space.
  • N: This corresponds to the non-secure address space.
  • SP: This corresponds to secure world physical memory.
  • NP: This corresponds to non-secure world physical memory.
The following are examples of DS-5 Debugger commands with address spaces for ARMv7 based processors:
  • break S:main
  • x N:0x80000000
  • add-symbol-file foo.axf SP:0.
When execution stops, DS-5 Debugger reports the current memory space, for example:
  • Execution stopped in SVC mode at S:0x80000000
  • Execution stopped in SYS mode at breakpoint 1: S:0x80000BA8.

Address spaces in ARMv8 based processors

The following address space prefixes might be available for ARMv8 based processors when in the AArch64 execution state:
  • EL3: This corresponds to the EL3 translation regime. This is a secure address space.
  • EL2: This corresponds to the EL2 translation regime. This is a non-secure address space.
  • EL1S: This corresponds to the Secure EL1 and Secure EL0 translation regimes.
  • EL1N: This corresponds to the Non-secure EL1 and Non-secure EL0 translation regimes.
  • SP: This corresponds to Secure world physical memory.
  • NP: This corresponds to Non-secure world physical memory.
The following address space prefixes might be available for ARMv8 based processors when in the AArch32 execution state:
  • S: This corresponds to the EL3, Secure EL1, and Secure EL0 translation regimes.
  • H: This corresponds to the EL2 translation regime. This is a Non-secure address space.
  • N: This corresponds to the Non-secure EL1 and Non-secure EL0 translation regimes.
  • SP: This corresponds to Secure world physical memory.
  • NP: This corresponds to Non-secure world physical memory.
The following are examples of DS-5 Debugger commands with address spaces for ARMv8 based processors:
  • break EL1N:main
  • x EL1S:0x80000000
  • add-symbol-file foo.axf SP:0.
When execution stops, DS-5 Debugger reports the current memory space, for example:
  • Execution stopped in EL3h mode at: EL3:0x0000000080001500
  • Execution stopped in EL1h mode at breakpoint 2.2: EL1N:0x0000000080000F6C
If the core is stopped in exception level EL3, the debugger cannot reliably determine whether the translation regime at EL1/EL0 is configured for secure or non-secure access. This is because the secure monitor can change this at run-time when switching between secure and non-secure worlds. Memory accesses from EL3, such as setting software breakpoints at EL1S: or EL1N: addresses, might cause corruption or the target to lockup.
The memory spaces for the EL1 and EL0 exception levels have the same prefix because the same translation tables are used for both EL0 and EL1. These translation tables are used for either Secure EL1/EL0 or Non-secure EL1/EL0. The consequence of this is that if the core, in AArch64 state, is stopped in EL0 in secure state, then the debugger reports: Execution stopped in EL0h mode at: EL1S:0x0000000000000000.

Note

The reported EL1S: here refers to the memory space that is common to EL0 and EL1. It does not refer to the exception level.
Related concepts
6.2 About accessing AHB, APB, and AXI buses
6.3 About virtual and physical memory
6.5 About debugging hypervisors
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