This is an unavoidably invasive commit, because it affects the unit tests
(which formerly exited using stop()), the test harness Verilog generator
(since it is no longer necessary), and the DRAM model (since it is no
longer connected). However, this should substantially reduce the effort
of building test harnesses in the future, since manual or semi-automatic
Verilog writing should no longer be necessary. Furthermore, there is now
very little duplication of effort between the Verilator and VCS test
harnesses.
This commit removes support for DRAMsim, which is a bit of an unfortunate
consequence. The main blocker is the lack of Verilog parameterization for
BlackBox. It would be straightforward to revive DRAMsim once support for
that feature is added to Chisel and FIRRTL. But that might not even be
necessary, as we move towards synthesizable DRAM models and FAME-1
transformations.
Until now, the number of L1 client channels was set statically in the
configuration. This static configuration also assumed the same number of
cached and uncached channels per tile. As we plan to move towards
heterogenous multicore systems, this restriction should be removed.
This commit changes the generator so that number of channels per tile
can be independently set (using cde.Parameters.alterPartial).
The OuterMemorySystem will dynamically compute the number of cached and
uncached channels by summing the number of each kind of channel per core.
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.
We need this to work for our chip, and it's not been tested in a long
time in upstream -- it didn't even used to build since the Nasti
conversion. This makes a few changes:
* Rather than calling the backup memory port parameters MEM_*, it calls
them MIF_* (to match the MIT* paramater objects). A new name was
necessary because the Nasti stuff is now dumped as MEM_*, which has
similar names but incompatible values.
* p(MIFDataBits) was changed back to 128, as otherwise the backup
memory port doesn't work (it only send half a TileLink transaction).
64 also causes readmemh to bail out, but changing the elf2hex parameters
works around that.
* A configuration was added that enabled the backup memory port in the
tester. While this is kind of an awkward way to do it, I want to
make sure I can start testing this regularly and this makes it easy to
integrate.
