This stores the most common SPRs in the register file.
This includes CTR and LR and a not yet final list of others.
The register file is set to 64 entries for now. Specific types
are defined that can represent a GPR index (gpr_index_t) or
a GPR/SPR index (gspr_index_t) along with conversion functions
between the two.
On order to deal with some forms of branch updating both LR and
CTR, we introduced a delayed update of LR after a branch link.
Note: We currently stall the pipeline on such a delayed branch,
but we could avoid stalling fetch in that specific case as we
know we have a branch delay. We could also limit that to the
specific case where we need to update both CTR and LR.
This allows us to make bcreg, mtspr and mfspr pipelined. decode1
will automatically force the single issue flag on mfspr/mtspr to
a "slow" SPR.
[paulus@ozlabs.org - fix direction of decode2.stall_in]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
We were copying in XER[SO] for the dot-form instructions but not the
explicit compare instructions. Fix this.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Some VHDL compilers like verific [1] don't like these, so let's remove
them. Lots of random code changes, but passes make check.
Also add basic script to run verific and generate verilog.
1. https://www.verific.com/
Signed-off-by: Michael Neuling <mikey@neuling.org>
Benjamin Herrenschmidt
Paul Mackerras
Michael Neuling