Debugging CVA6 APU on a KC705 board
Created by: Juan-Gg
I am attempting to get the CVA6 APU running on a KC705 board.
What I have done so far:
- Cloned the CVA6 repository, installed the tools and successfully ran smoke-tests.sh
- Ran $make fpga BOARD=kc705, and obtained the ariane_xilinx.mcs file.
- Programmed the kc705’s configuration memory using this file. I am using Vivado 2018.2.
- When pressing the “FPGA Prog” button, after about 3 minutes the “GPIO LEDS” start flashing, four in a counting pattern and the other four in a shifting pattern. No UART activity.
- I prepared an SD card with the Ariane 4.2 image (https://github.com/openhwgroup/cva6-sdk/releases), when powering on with this SD card I could not see any activity on the UART.
- Following the instructions here: https://github.com/openhwgroup/cva6?tab=readme-ov-file#debugging, I tried to debug the design. When I run “openocd -f ariane.cfg”, it does not find the core. I get the following output:
ubuntu@ubuntu-2204:~/Documents$ openocd -f ariane.cfg
Open On-Chip Debugger 0.11.0
Licensed under GNU GPL v2
For bug reports, read
http://openocd.org/doc/doxygen/bugs.html
DEPRECATED! use 'adapter speed' not 'adapter_khz'
DEPRECATED! use 'adapter driver' not 'interface'
Info : auto-selecting first available session transport "jtag". To override use 'transport select <transport>'.
Info : clock speed 1000 kHz
Error: JTAG scan chain interrogation failed: all ones
Error: Check JTAG interface, timings, target power, etc.
Error: Trying to use configured scan chain anyway...
Error: riscv.cpu: IR capture error; saw 0x1f not 0x01
Warn : Bypassing JTAG setup events due to errors
Error: Unsupported DTM version: 15
Warn : target riscv.cpu examination failed
Info : starting gdb server for riscv.cpu on 3333
Info : Listening on port 3333 for gdb connections
Error: Target not examined yet
Error: Unsupported DTM version: 15Any ideas on what may be going wrong? What do the LEDs mean? I could not find any documentation on these. Thanks.