• ARMv7: How to set SP in secure and non secure mode ?
    Hello, I'm working on Raspberry PI2, ARMv7 and now specifically trying the secure modes. I managed to get the PI start in secure state, then here I can set the SP for all the modes I intend to use...
  • Differences between Privilege Modes and Non-Privilege Mode ?
    Hi everyone , I'm currently using a Cortex-A9 processor (NXP Freescale i.MX6S). My project is to develop a simple OS, but I met a problem: When I am trying to control some peripherals (such as...
  • Security Extensions and Privilege Levels
    Introduction In ARM® Cortex®-A class CPUs, the Memory Management Unit (MMU) and Operating System (OS) work together to protect address spaces. A process running in unprivileged mode has its own virtual...
  • Security Extensions in ARMv7
    "the Security Extensions integrate hardware security features into the architecture". Please can anybody make clear what exactly is "security" in hardware point of view in an ARMv7-A profile..? can you...
  • Privilege mode on CM0+
    CM0+ reference manual said the below. Unprivileged The software:      - xxxx      - xxxx      - Might have restricted access to memory or peripherals. Here, I don't know what is meaning the last line...