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RISC-V Instruction Set Manual
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menvcfg.CBIE not specified as WARL or other behavior #1682

Closed davidharrishmc closed 1 month ago

davidharrishmc commented 1 month ago

menfcfg is defined in privileged spec Section 3.1.18 Figure 25. CBIE is a 2-bit field, with the 10 encoding Reserved (see unprivileged spec Table 23).

The privileged spec does not define the behavior of writing 10 to menvcfg.CBIE. Should it be WARL, WLRL, WPRI, etc. ?

aswaterman commented 1 month ago

@gfavor any objections to changing this text to declare the field WARL? That's what Spike does.

gfavor commented 1 month ago

No objections. And I assume you feel that WARL is more appropriate than WLRL (as well as being what Spike does)?

aswaterman commented 1 month ago

Yeah, in this case, it seems preferable to leaving the machine in an unspecified state.