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How to set inner of outer shareability on page table entry WITHOUT TEX remap??

At first, sorry to my fool English.

I want to know how to set to inner or outer shareable attribute on page table entry using TEX, C, B and  S bit (without TEX remap).

I knew if i use TEX remap, the PRRR NOT bit used to set to outer or inner but i didn't find explain in without TEX remap.

Thanks.

Parents
  • Hi levi,

    The quick answer is that you can just set the TEX encoding to reflect the shareability and use the "S" bit for certain encodings, you just can't set inner/outer shareability separately - but certain TEX values do infer shareability for both regions. This is documented in B3.8.2 of the ARMv7-AR ARM ("Short-descriptor format memory region attributes, without TEX remap."

    Ta,

    Matt

Reply
  • Hi levi,

    The quick answer is that you can just set the TEX encoding to reflect the shareability and use the "S" bit for certain encodings, you just can't set inner/outer shareability separately - but certain TEX values do infer shareability for both regions. This is documented in B3.8.2 of the ARMv7-AR ARM ("Short-descriptor format memory region attributes, without TEX remap."

    Ta,

    Matt

Children
  • Thanks a lot your answer. But i have still a question.. when i see ur mentioned part, i can find this.

    quest.PNG

    i think these bit define cash policy about inner/outer. but is it related also to SHAREABLITIY??

    for example when TEX 000, B 1 C 1 ===> Cuz it defind Outer and Inner policy of cash, it also implies inner/outer shareability.

                                  and when using last one (TBX : 1BB , C:A, B:A), Could i set sharability of inner/outer with cashability of that?

    Thanks.

  • Hi levi,

    It's the right-hand column - it's either (Inner AND Outer) Shareable, (Inner AND Outer) Non-Shareable, or controlled by the S bit (one bit controls both Inner AND Outer shareability).

    Ta,

    Matt