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trustzone translation table

Note: This was originally posted on 15th November 2011 at http://forums.arm.com

After reading the documents in the website, i am quite puzzled about the trustzone feature.
1. Can i disable trustzone extension?
2. Each world has its own virtual processor, virtual mmu and translation table. How to make sure that the normal world can't access the secure world memory? The normal world can't see the physical address of the secure world? Or it can translate the virtual address to the physical address of the secure world, but it can't access that region of memory?
3. Normal world ignores the NS bit in the translation table. So it can access all the physical memory in normal world?
I have read the book: ARM Security Technology: Building a Secure System Using TrustZone Technology, ARM Architecure Reference Manual and ARM Cortex-A programming guide. Did i miss the important part? Can anyone advise me some books regarding the arm cortex-a architecture? I am a beginner at ARM. Thanks.
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  • Note: This was originally posted on 16th November 2011 at http://forums.arm.com

    Thanks, ttfn.
    I have one more question.

    since the normal world can only see the non-secure physical address space, so the normal can address 4G space. the secure world can see the secure and non-secure physical address space, so it can address 8G space. is that right?
    for example, you want to access a virtual address in the secure world and that virtual address is marked as secure in the translation table in the secure world. my question is: how to access the same virtual address which is marked as non-secure in the secure world?

    By the way, i can't find any resources about what you have said about trustzone. Could you provide me some materials?

    Thanks
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  • Note: This was originally posted on 16th November 2011 at http://forums.arm.com

    Thanks, ttfn.
    I have one more question.

    since the normal world can only see the non-secure physical address space, so the normal can address 4G space. the secure world can see the secure and non-secure physical address space, so it can address 8G space. is that right?
    for example, you want to access a virtual address in the secure world and that virtual address is marked as secure in the translation table in the secure world. my question is: how to access the same virtual address which is marked as non-secure in the secure world?

    By the way, i can't find any resources about what you have said about trustzone. Could you provide me some materials?

    Thanks
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