32 lines
1.4 KiB
ReStructuredText
32 lines
1.4 KiB
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******************************
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Memory Managment Unit on ARM64
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******************************
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This part describes the memory managment unit on ARM64 and how it is used by the debugger.
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Single Level Pagetable at EL3
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=============================
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The documentation described here can also be found at the `official ARM documentation <https://developer.arm.com/documentation/102416/0100/Single-level-table-at-EL3>`_.
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Translation Regime
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******************
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Register ``TCR_ELx`` is used to control the **Tranlation Regime** for the pagetables. The documentation for the ``TCR_EL3`` can be found in the `official ARM documentation <https://developer.arm.com/documentation/ddi0500/d/system-control/aarch64-register-descriptions/translation-control-register--el3>`_.
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Translation Table
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*****************
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The location of the page table is located in register ``ttbr0_el3``. Depending of the configuration of ``TCR_EL3`` the bits for address selection can change.
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More documentation can be found `here <https://developer.arm.com/documentation/ddi0595/2021-06/AArch64-Registers/TTBR0-EL3--Translation-Table-Base-Register-0--EL3->`_
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Pagetable Entry
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***************
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The following diagram shows the format of a stage 1 level 1 table entry on EL3.
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.. image:: images/mmu/singlelevel_el3_pte.png
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Automatic Paging
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================
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Automatic paging for page walking will be setup in the debugger.
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For this the ``ARM64_Concrete_State`` contains a mmu with class ``ARM64_MMU``.
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