Rocket Rocc Examples Save

Collection of example libraries and test programs for the existing Rocket Custom Coprocessor (RoCC) accelerators for Rocket Chip.

Usage

Install the RISC-V toolchain and make sure that it's on your path. You need to pass the path to riscv-tools in as an argument to configure --with-riscvtools=$PATH_TO_RISCV_TOOLS.

autoconf
mkdir build && cd build
../configure --with-riscvtools=$PATH_TO_RISCV_TOOLS
make

This creates two classes of tests:

• bareMetal -- Bare metal tests like RISCV Tests
• pk -- Tests that use the Proxy Kernel

Bare Metal tests can be run directly on the emulator (for instructions on how to build this see the following section), e.g.:

emulator-freechips.rocketchip.system-RoccExampleConfig bareMetal/examples-bareMetal-p-accumulator

Proxy Kernel tests are ELFs and need the Proxy Kernel (or Linux). You must first patch the Proxy Kernel so that the XS bits allow access to the "extension" (the RoCC). You can change this manually or use the provided patch (patches/riscv-pk.patch):

cd $RISCV_PK_DIR
git apply $THIS_REPO_DIR/patches/riscv-pk.patch

mkdir build
cd build
../configure --prefix=$RISCV/riscv64-unknown-elf --host=riscv64-unknown-elf
make
make install

Following that, you can run Proxy Kernel tests, e.g., :

emulator-freechips.rocketchip.system-RoccExampleConfig pk pk/examples-pk-accumulator

Building a Rocket Chip Emulator

Build a rocket-chip emulator with the RoCC examples baked in and run the provided test program:

cd $ROCKETCHIP_DIR/emulator
make CONFIG=RoccExampleConfig

Expected Run Time

The included test should run for ~5 million cycles over a wall clock time of ~5 minutes.

> time $ROCKETCHIP_DIR/emulator-freechips.rocketchip.system-RoccExampleConfig -c pk pk/examples-pk-accumulator
[INFO] Write R[1] = 0xdead
[INFO] Read R[1]
[INFO]   Received 0xdead (expected 0xdead)
[INFO] Accum R[1] with 0xffffffffffffe042
[INFO] Read R[1]
[INFO]   Received 0xbeef (expected 0xbeef)
[INFO] Load 0xbad (virt: 0x0xfee9ac0, phys: 0x0x8ffffac0) via L1 virtual address
[INFO] Read R[1]
[INFO]   Received 0xbad (expected 0xbad)
Completed after 3278954 cycles

real	5m2.738s
user	5m0.262s
sys	0m1.179s