Re: [PATCH] Add direct memory access synchronize extension
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-----Original Message-----It's not that simple. Providing shared executable code pages from M-mode to S-mode means: 1) We will have to define ABI for entry/exit of functions in this shared 2) Define a format of function table offset which M-mode can export to S-mode in the shared code pages itself. Let's have a simple SBI DMA sync extension in SBI v0.4 spec.I was thinking that as part of the extension, we can have an SBI call that wouldI'm not veryThat's what I am thinking. The only additional cost is just a "ecall The shared code pages between M-mode and S-mode will have it's own Challenges and we will have to define more stuff in SBI spec to support this (see above). It seems CMO extension might freeze sooner than we think (others can comment on this). If CMO extension is frozen by year end then we can trap-n-emulate CMO instructions instead of SBI DMA sync extension. If it does not freeze by year end then we will have to go ahead with SBI DMA sync extension as stop-gap solution. Regards, Anup
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