We are planning on switching to a TileLink interconnect throughout and
convert to AXI only on the very edge. Therefore, we need to get rid of
all the existing AXI masters other than the TileLink to AXI converter.
* Get rid of DMA engine for now
* Connect RTC to TileLink interconnect instead of AXI interconnect
Chisel 3 can't build the C++ emulator, so we currently can't have direct
support for testing RocketChip. We can at least test to see if the
Verilog builds when run through Chisel 3, which this patch does.
This allows users to specify if they want to build RocketChip against
Chisel 2 or 3. Since Chisel 3 is now open source we can add these
submodule pointers directly to avoid a fork of upstream.
(1) Introduce tracegen.py, a script that invokes the emulator (built
with TraceGenConfig), sending a SIGTERM once all cores are finished.
(2) Update toaxe.py to gather some statistics about the trace.
(3) Introduce tracestats.py, which displays the stats in a useful way.
(4) Introduce tracegen+check.py, a top-level script that generates
traces, checks them, and emits stats. If this commit is pulled, it
should be done after pulling my latest groundtest commit.
It turns out the Chisel C++ backend can't emit correct initialization
code for a 128 bit wide NastiROM. Rather than trying to fix Chisel, I'm
just going to hack up the backup memory port Verilog harness a bit more
to make it work.
Note that the backup memory port Verilog already couldn't take arbitrary
parameters for MIF_*, so it's not like we're losing any flexibility
here.
The backup memory port doesn't work on multi-channel configurations, it
just screws up the Nasti tag bits. This patch always instantiates a
single-channel backup memory port, which relies on the memory channel
selector to only enable a single memory channel when the backup memory
port is enabled. There are some assertions to make sure this happens,
as otherwise memory gets silently corrupted.
While this is a bit of a hack, the backup memory port will be going away
soon so I don't want to spend a whole lot of time fixing it. The
generated hardware is actually very similar: we used to elaborate a
Nasti arbiter inside the backup memory support, now there's one outside
of it instead.