openrisc / mor1kx

mor1kx - an OpenRISC 1000 processor IP core
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Data bus Wishbone Interface Formal Check fails #134

Open Harshitha172000 opened 3 years ago

Harshitha172000 commented 3 years ago

Properties that failed:

  1. The direction of the write enable shouldn't change within a series of strobe/requests.
  2. Within any given bus cycle, the direction may only change when there are no further outstanding requests

Solver picks up a case where the write enable changes due to atomic signal transition.

Code: https://github.com/openrisc/mor1kx/blob/master/bench/formal/fwb_master.v#L173#L186

Trace showing failure:

image

stffrdhrn commented 3 years ago

can you put a link to the code, or mention the module where this is happening?

Harshitha172000 commented 3 years ago

Wishbone Interface referring to mor1kx.v module.