Cores-SweRV

SweRV EH1 core SweRV RISC-V CoreTM from Western Digital This repository contains the SweRV CoreTM design RTL

License By contributing to this project, you agree that your contribution is governed by Apache-2.0. Files under the tools directory may be available under a different license. Please review individual file for details.

Directory Structure ├── configs # Configurations Dir │ └── snapshots # Where generated configuration files are created ├── design # Design root dir │ ├── dbg # Debugger │ ├── dec # Decode, Registers and Exceptions │ ├── dmi # DMI block │ ├── exu # EXU (ALU/MUL/DIV) │ ├── ifu # Fetch & Branch Prediction │ ├── include
│ ├── lib │ └── lsu # Load/Store ├── docs ├── tools # Scripts/Makefiles └── testbench # (Very) simple testbench ├── asm # Example assembly files └── hex # Canned demo hex files Dependencies Verilator (3.926 or later) must be installed on the system If adding/removing instructions, espresso must be installed (used by tools/coredecode) Quickstart guide Clone the repository Setup RV_ROOT to point to the path in your local filesystem Determine your configuration {optional} Run make with tools/Makefile Configurations SweRV can be configured by running the $RV_ROOT/configs/swerv.config script:

% $RV_ROOT/configs/swerv.config -h for detailed help options

For example to build with a DCCM of size 64 :

% $RV_ROOT/configs/swerv.config -dccm_size=64

This will update the default snapshot in $RV_ROOT/configs/snapshots/default/ with parameters for a 64K DCCM.

Add -snapshot=dccm64, for example, if you wish to name your build snapshot dccm64 and refer to it during the build.

This script derives the following consistent set of include files :

$RV_ROOT/configs/snapshots/default ├── common_defines.vh # defines for testbench or design ├── defines.h # #defines for C/assembly headers ├── pd_defines.vh # defines for physical design ├── perl_configs.pl # Perl %configs hash for scripting ├── pic_ctrl_verilator_unroll.sv # Unrolled verilog based on PIC size ├── pic_map_auto.h # PIC memory map based on configure size └── whisper.json # JSON file for swerv-iss Building a model Set the RV_ROOT environment variable to the root of the SweRV directory structure

RV_ROOT = /path/to/swerv export RV_ROOT

Create your configuration

(Skip if default is sufficient) (Name your snapshot to distinguish it from the default. Without an explicit name, it will update/override the default snapshot) $RV_ROOT/configs/swerv.config [configuration options..] -snapshot=mybuild

Snapshots are placed in $RV_ROOT/configs/snapshots// directory

Build with verilator:

make -f $RV_ROOT/tools/Makefile verilator [snapshot=name]

This will create and populate the verilator obj_dir/ in the current work dir.

Other targets supported:

vcs (Synopsys)
irun (Cadence)
Running a simple Hello World program (verilator) RV_ROOT = /path/to/swerv export RV_ROOT

make -f $RV_ROOT/tools/Makefile verilator-run This will build a verilator model of SweRV with AHB-lite bus, and execute a short sequence of instructions that writes out "HELLO WORLD" to the bus.

You can re-execute using

./obj_dir/Vtb_top

Start of sim

---

Hello World from SweRV @WDC !!

Finished : minstret = 389, mcycle = 1658

End of sim A vcd file sim.vcd is created which can be browsed by gtkwave or similar waveform viewers. trace_port.csv contains a log of the trace port.

The Makefile allows you to specify different assembly files from command line

make -f $RV_ROOT/tools/Makefile verilator-run ASM_TEST=my_hellow_world.s ASM_TEST_DIR=/path/to/dir If you change only the assembly files, you do not need to rebuild verilator, just specify the target as program.hex :

make -f $RV_ROOT/tools/Makefile program.hex ASM_TEST=my_hello_world.s ASM_TEST_DIR=/path/to/dir ./obj_dir/Vtb_top Western Digital, the Western Digital logo, G-Technology, SanDisk, Tegile, Upthere, WD, SweRV Core, SweRV ISS, and OmniXtend are registered trademarks or trademarks of Western Digital Corporation or its affiliates in the US and/or other countries. All other marks are the property of their respective owners.