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Clarify Memory Access acts like data access. #1065

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merged 1 commit into from
Aug 22, 2024
Merged

Clarify Memory Access acts like data access. #1065

merged 1 commit into from
Aug 22, 2024

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rtwfroody
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I'm not sure if this is necessary. Does RISC-V allow data loads to differ from instruction fetches? For a long time any mention of caches was avoided in all specs.

Inspired by #1062.

@pdonahue-ventana
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Does RISC-V allow data loads to differ from instruction fetches?

Yes. The Zifencei chapter of the unpriv spec says: "RISC-V does not guarantee that stores to instruction memory will be made visible to instruction fetches on a RISC-V hart until that hart executes a FENCE.I instruction."

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I would say something more like "This command lets the debugger perform memory accesses, with the exact same memory view and permissions as performing a load/store on the selected hart." Then that leads nicely into the next sentence about memory-mapped registers.

I'm not sure if this is necessary. Does RISC-V allow data loads to
differ from instruction fetches? For a long time any mention of caches
was avoided in all specs.

Inspired by #1062.
@rtwfroody
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@pdonahue-ventana sounds good. Changed.

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Great

@rtwfroody rtwfroody merged commit 40f80ef into main Aug 22, 2024
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@rtwfroody rtwfroody deleted the memory_access branch August 22, 2024 18:17
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2 participants