Darkhan Kubigenov kdarkhan

Normally to cross compile a LineageOS kernel requires a massive amount of storage as it requires downloading the entirety of the android source, including building LineageOS itself, which you may not care to do if you just want to fiddle with kernel configuration or patching.

Here's a way around that! (In the form of a script with comments.)

Special thanks to this blog post in particular, which does a decent job of explaining what to do-- hopefully my comments offer some additional clarification.

Docker on Android 🐋📱

Edit 🎉

All packages, except for Tini have been added to termux-root. To install them, simply pkg install root-repo && pkg install docker. This will install the whole docker suite, left only Tini to be compiled manually.

Summary

What is OpenOCD? Why Raspberry Pi and not ROCK64 or Nvidia Jetson Nano?

OpenOCD (Open On-Chip Debugger) is the open-source tool that we use to flash and debug PineTime.

OpenOCD runs on our Raspberry Pi and connects via GPIO Pins to the SWD (Serial Wire Debug) port of PineTime to perform flashing and debugging.

Because SWD is a serial protocol, OpenOCD needs to have very precise timing in order to control PineTime correctly. (More about SWD)

OpenOCD on Raspberry Pi uses the Broadcom GPIO driver to achieve precise timing. We can see this in the OpenOCD configuration file for Raspberry Pi: swd-pi.ocd

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

	; Autohotkey Capslock Remapping Script
	; - Deactivates capslock for normal (accidental) use.
	; - Hold Capslock and drag anywhere in a window to move it (not just the title bar).
	; - Access the following functions when pressing Capslock:
	;Cursor keys - h, j, k, l
	;Home,End - N, ;
	;Page up,down - - =
	;Esc - CapsLock only
	;CapsLock - Space