16 lines
629 B
Markdown
16 lines
629 B
Markdown
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# x86_32 PAE documentation
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Due to missing x86_64 support it's required to use PAE enabled x86_32 code.
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The corresponding functions can be found in ``src/cpu/x86/pae/``.
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## Memory clearing helper functions
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To clear all DRAM on request of the
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[Security API](../../security/memory_clearing.md), a helper function can be used
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called `memset_pae`.
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The function has additional requirements in contrast to `memset`, and has more
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overhead as it uses virtual memory to access memory above 4GiB.
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Memory is cleared in 2MiB chunks, which might take a while.
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Make sure to enable caches through MTRRs, otherwise `memset_pae` will be slow!
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