Help: Ingenic XBurst2 X2000 SoC series USB serial port connetion

[andreoliveirapguerra]

I saw that there is a sand clock on the X2000 USB serial port, does it means it does not have those capabilities?

Context: I own a Creality K1 3d printer, which uses an modified board that runs on the X2000 and the ingenic linux kernel. But while trying to get an serial connetion, I cannot seem to be able to get the board and kernel to recognize the other USB.
the lsusb command returns to me:
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
and the ls /dev/tty* command outputs this:

/dev/tty    /dev/tty15  /dev/tty22  /dev/tty3   /dev/tty37  /dev/tty44  /dev/tty51  /dev/tty59  /dev/tty9
/dev/tty0   /dev/tty16  /dev/tty23  /dev/tty30  /dev/tty38  /dev/tty45  /dev/tty52  /dev/tty6   /dev/ttyS0
/dev/tty1   /dev/tty17  /dev/tty24  /dev/tty31  /dev/tty39  /dev/tty46  /dev/tty53  /dev/tty60  /dev/ttyS1
/dev/tty10  /dev/tty18  /dev/tty25  /dev/tty32  /dev/tty4   /dev/tty47  /dev/tty54  /dev/tty61  /dev/ttyS2
/dev/tty11  /dev/tty19  /dev/tty26  /dev/tty33  /dev/tty40  /dev/tty48  /dev/tty55  /dev/tty62  /dev/ttyS3
/dev/tty12  /dev/tty2   /dev/tty27  /dev/tty34  /dev/tty41  /dev/tty49  /dev/tty56  /dev/tty63  /dev/ttyS5
/dev/tty13  /dev/tty20  /dev/tty28  /dev/tty35  /dev/tty42  /dev/tty5   /dev/tty57  /dev/tty7   /dev/ttyS7
/dev/tty14  /dev/tty21  /dev/tty29  /dev/tty36  /dev/tty43  /dev/tty50  /dev/tty58  /dev/tty8   /dev/ttyS9

The build roots for this were:
ftp://ftp.ingenic.com.cn/DevSupport/X2000/X2000/01_SW/07_kernel4.4.94_x2000-sdk_v8.0-20220125 ftp://ftp.ingenic.com.cn/DevSupport/X2000/X2000/01_SW/01_Buildroot_dl

The modded creality board from their official github here:
https://github.com/CrealityOfficial/K1_Series_Annex/blob/main/pin%20out/motherboard-en.PNG

[ReimuNotMoe]

What do you mean by sand clock?

Sorry, but we are unable to give support for devices that use Ingenic's own outdated 4.4 kernel.

[andreoliveirapguerra]

I see, than do you know how could I perhaps use this kernel on the board? Creality offers tools for flashing the image, so if perhaps could flash this ingenic comunity board, could I perhaps get it to recognize USB devices properly? Or this Ingenic comunity does not have image for the XBurst2 X2000?

My final objective is simply to obtain serial uart connection from the board, so I can connect it to an rasp that will act as the main MCU and give commands to the X2000. To be able to run octoprint on the printer.

[ClassicOldSong]

We currently haven't add support for the X2000. You may wait a few months later since we're planning on adding support for the X2000 but we might not be able to provide help for that specific board.

[ClassicOldSong]

Also X2000 is very capable, there's totally no need for a RPI as a host.

[X-Ryl669]

Also, even if you had a fully working kernel, you won't have the device tree used in Creality's screen module, nor the pinout, nor the GUI software, nor all the additional stuff Creality made to their kernel/drivers for this board to work. I think, unless Creality deliver the source code for their module, you're struck. You might be able to compile Octoprint on Ingenic's MIPS ISA and run it directly on the board itself.

It's very likely the printer motherboard already discuss on the plain serial line (/dev/ttyS something and not USB), so once you've installled octoprint or moonraker, you'll be able to control it.

[ReimuNotMoe]

It's quite easy to dump the device tree in use from /proc/device-tree/. If the kernel is too old, one can always dump the GPIO pinmux registers using busybox devmem <reg>. So no problem for the pinout part.

[pavels]

As for the DT and LCD

I actually did it - https://github.com/k1-debian/linux

Panel Init Code: https://github.com/k1-debian/linux/blob/master/module_drivers/drivers/video/fbdev/ingenic/fb_stage/displays/creality_lcd/panel-creality-lcd.c

DT: https://github.com/k1-debian/linux/blob/master/module_drivers/dts/creality_k1.dts

the code https://github.com/k1-debian/linux is based off of Ingenic Kernel Tree so it use their LCD driver (there are 2 parts - the ingenic LCD peripheral, which acts like a framebuffer device in linux, and the driver for the panel, which is responsible for initializing the LCD panel)

now maybe somebody here can help (sorry for hijacking this issue a bit) - i ended up in a dead end with the ingenic tree. Both 5.x and 6.x branches tends to freeze when the UART peripheral is used a lot (the case in 3D printer control board) - and by freeze i mean complete - not kernel panic - the CPU just stops working. The creality board has no JTAG broken out - so no chance there.

Did somebody here heard about such issue? Maybe some clues?

[X-Ryl669]

If you know which pins the JTAG pins should be on this SOC, you can try to solder wires directly on those. It's very likely they are traces for these signals on the board, even if they don't end up on a connector, since it's how many board are first programmed. Based on this page 21, it's on pin (C6 B6 A6 A7 D6). You'll need openocd too and a JTAG probe.

Without such feature, it'll be impossible to debug, even if you rerouted the kernel output to another UART line, if it freezes/crash before it can log anything, you won't be able to know what happens. Even with JTAG and a debugger, it's already very hard to debug, at best, you'll be able to find out where the PC is for the current CPU, but you won't be able to switch threads and if it's crashed, it's likely the PC is not relevant anyway. Maybe you'll be able to inspect the stack and the memory around by / pointer to the registers. It's all guess work here.