+- PINE64 (https://forum.pine64.org)
+-- Forum: General (https://forum.pine64.org/forumdisplay.php?fid=1)
+--- Forum: Getting Started (https://forum.pine64.org/forumdisplay.php?fid=21)
+--- Thread: Star64: jtag debugging? (/showthread.php?tid=18508)
Star64: jtag debugging? - bluepill - 07-15-2023
I'm thinking of getting a Star64 to do some practical learning about operating system development and I haven't been able to find some clear/simple information about compatible equipment and the process for setting up a jtag debugging environment. Please note that my experience is mostly with software and I am really, really new to working so close to the hardware.
The Star64 schematics show GPIO pins 0 to 4 for debug trace and pins 9 to 13 for jtag HIFI4 (audio DSP). From the very little that I know about jtag this is the minimum number of pins - so minimum amount of jtag functionality.
I have been looking at the Segger J-Link Edu because it has support for the U74 and E24 SiFive cores in the Star64, but I'm not sure if it is a good choice.
Has anyone setup jtag debugging for the Star64? What hardware/software are you using and can you recommend a beginners guide that can get me started?
RE: Star64: jtag debugging? - bwooster0 - 09-20-2023
I am using a j-link edu with my star64 board. I am using a macbook pro with my jlink edu. I also connected to the uart pins on the star64.
Here are the pins that need to be connected from the edu to the star64 gpio pins:
JLinkEdu pin Star64 gpio pin
1 40
3 36
5 38
7 35
9 37
1 2
I couldn't figure out how to use the jlinkexe software to connect to the different cores of the jh7110.
I WAS able to use openocd to connect and see all the cores. I was able to load different programs onto different cores.
I used openocd with the following text in a config file:
>>>>
// config.tcl
adapter driver jlink
reset_config trst_only
transport select jtag
adapter speed 4000
jtag newtap e24 cpu -irlen 5
jtag newtap u74 cpu -irlen 5
#target create e24.cpu0 riscv -chain-position e24.cpu -coreid 0
target create u74.cpu0 riscv -chain-position u74.cpu -coreid 0 -rtos hwthread
target create u74.cpu1 riscv -chain-position u74.cpu -coreid 1
target create u74.cpu2 riscv -chain-position u74.cpu -coreid 2
target create u74.cpu3 riscv -chain-position u74.cpu -coreid 3
target create u74.cpu4 riscv -chain-position u74.cpu -coreid 4
#target smp u74.cpu0 u74.cpu1 u74.cpu2 u74.cpu3 u74.cpu4
init
>>>>
There isn't much general documentation for the JH7110. I did write a simple assembly program that wrote to the serial board.
I was able load the program onto the board using openocd. It was fun seeing 4 cores all writing to the serial port at the same time!