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riscv / riscv-CMOs

https://jira.riscv.org/browse/RVG-59
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Is there a required/suggested legalization value for writing xenvcfg.CBIE to 2'b10? #65

Closed YenHaoChen closed 1 year ago

YenHaoChen commented 1 year ago

Hello,

The xenvcfg.CBIE has a reserved value of 2'b10. Thus, writing the reserved value 2'b10, an implementation should legalize to another legal value.

Is there a required/suggested legalization value for writing xenvcfg.CBIE to 2'b10?

Thank you.

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gfavor commented 1 year ago

As with WARL fields in general, there is no required or suggested legalization value. So you're free to choose whatever you think is best. One view would say to legalize to the conservative (and all 0's) value that raises an exception on CBO.INVAL usage - for the sake of more readily catching what one would probably consider to be a programming error.

YenHaoChen commented 1 year ago

Thank you.