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Add sfence.vma in the disable_pmp function #537
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SFENCE.VMA is illegal on implementations without S-mode. I think this should be conditionalized.
PMP changes require an SFENCE.VMA on any hart that implements page-based virtual memory, even if VM is not currently enabled. If the implementation without S-mode, does this mean that PMP registers are optional? |
As you said, "any hart that implements page-based virtual memory" needs to execute SFENCE.VMA. If S-mode is not implemented, then the hart doesn't implement page-based virtual memory. So there's no contradiction here. But I did misspeak earlier. It is true that SFENCE.VMA is illegal on implementations without S-mode. But it is also illegal on implementations with S-mode but without virtual memory. So, it needs to be conditionalized on "is S-mode implemented" and "is page-based virtual memory implemented". You can determine the latter property by checking whether But note that writing |
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Signed-off-by: liangzhen <zhen.liang@spacemit.com> Change-Id: Ief659c0e68618f5b08a1eee98bc7df92817b8b51
Thank you for your explanation,I've introduced an implements_page_virtual_memory property for the target. But, There is a pipeline failure in Build Spike. |
I think we need to do something similar to the following. Can you give it a try and see if you can make it work? https://github.com/riscv-software-src/riscv-isa-sim/pull/1584/files |
Yes, It works now. |
Change-Id: Ief659c0e68618f5b08a1eee98bc7df92817b8b51