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   Lup Yuen Lee 李立源 (lupyuen@qoto.org)'s status on Monday, 18-Mar-2024 23:32:27 JST Lup Yuen Lee 李立源

   #RISCV "Wait for Interrupt instruction (WFI) provides a hint to the implementation that the current hart can be stalled until an interrupt ... so a legal implementation is to simply implement WFI as a NOP" 🤔

   Source: https://github.com/riscv/riscv-isa-manual/releases/download/Priv-v1.12/riscv-privileged-20211203.pdf

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     🎓 Doc Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Tuesday, 19-Mar-2024 01:21:15 JST 🎓 Doc Freemo :jpf: 🇳🇱

     in reply to

     • AmpBenzScientist

     @AmpBenzScientist

     No, the whole point of an interrupt is that it isnt a conditional NOP.

     @lupyuen

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     ampbenzscientist@qoto.org's status on Tuesday, 19-Mar-2024 01:21:21 JST AmpBenzScientist

     in reply to

     @lupyuen Wait For Interrupt would be a conditional NOP wouldn't it? Perhaps it's fine, but it just seems wrong to use it like that. Not wrong as in it won't work but wrong as in it works and that's fine.

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     ampbenzscientist@qoto.org's status on Tuesday, 19-Mar-2024 02:51:21 JST AmpBenzScientist

     in reply to

     • 🎓 Doc Freemo :jpf: 🇳🇱

     @freemo @lupyuen It makes more sense when I look at an RTOS. It also makes sense why it's in the Privileged category.

     A few NOPs exist in RISC-V but it's rather clever that WFI would be used instead of NOP. It should allow time sensitive operations to run as soon as they become ready.