Differential D39828
arm64 pmap: introduce PHYS_TO_PTE macro Authored by zachary.leaf_arm.com on Apr 26 2023, 12:25 PM. Tags None Referenced Files
Details Introduce macro for PHYS_TO_PTE, setting the groundwork for future For extensions such as 52-bit VA/PA (FEAT_LPA2), the representation of Currently PHYS_TO_PTE is a NOP. Replace all instances where we go from Sponsored by: Arm Ltd
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Event TimelineComment Actions I was initially confused by the macro name and no description. The purpose is to convert a physical address into the output address field of a PTE, not into PTE. At least a comment would be useful, if not a different name. Comment Actions Right. This is really only the first step in creating a PTE, we still need to set all the required attribute bits etc. It's just about changing the representation back to the input address/pte format. e.g. for FEAT_LPA2, bits 51:50 of an OA are represented by bits 9:8 of the PTE so that will need switching around. The only alternative I can think of is PA_TO_IA(...) but not sure that's any clearer and we lose the symmetry with PTE_TO_PA; have added a comment as suggested and updated commit message. At least for now this step is mostly about documenting places where this change of representations will need to happen. Comment Actions I'm not sure it's immediately clear that the OA in PA_TO_PTE_OA refers to the PTE field name. I find that slightly confusing since the PA *is* the OA. We're going from OA -> IA not the other way around. Comment Actions
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