Support Quartus into VtR flow

[mithro]

Verilog to Routing supports using Quartus as a frontend for synthesis and then VtR for doing the place and route. You can find out more about this flow @ http://www.eecg.utoronto.ca/~kmurray/titan/fpl_13_demo.pdf

It would be really great if there was inbuilt support in FuseSoC / edalize for this flow. It would mean we could get more real world designs into the VtR benchmarks (and thus enable more research that is applicable to real world stuff!).

The process seems to be;

3. VQM GENERATION

To generate BLIF, a Verilog Quartus Map (VQM) file must first be produced by Quartus II. To enable VQM generation, hidden variables must be added to Quartus settings file (.qsf) before synthesis is performed. This is shown in Listing 2 for the Stratix IV family.

Listing 2: Assignments added to the .qsf for VQM Generation

set_global_assignment -name INI_VARS "qatm_force_vqm=on;vqmo_gen_sivgx_vqm=on"

The VQM is generated by first synthesizing and merging the design, and finally writing out the VQM. The commands are shown in Listing 3.

Listing 3: Synthesizing & Generating the VQM

$ quartus_map bitcoin_small
$ quartus_cdb bitcoin_small --merge
$ quartus_cdb bitcoin_small --vqm=bc_small.vqm

4. VQM TO BLIF CONVERSION

The plain-text VQM can now be converted to BLIF, using the vqm2blif tool, as shown in Listing 5. Advanced usage is described in vqm2blif’s documentation.

Listing 5: VQM to BLIF conversion

$ ../vqm2blif/vqm2blif.exe -vqm bc_small.vqm -arch ../test_arch.xml -out bc_small.blif

5. RUNNING VPR

The generated BLIF file can now be used in academic CAD tools that read BLIF. Figure 1 shows the placement generated by VPR [2], created with the command shown in Listing 6.

Listing 6: VPR command to generate Figure 1

$ vpr ../test_arch.xml bc_small.blif --timing_analysis off

[mithro]

FYI -- @acomodi @kgugala