Palm Pre (palm-castle)

The Palm Pre (codenamed 'Castle' ) is the first device in a line of devices released running Palm's then-new webOS software, which was based on Linux.

The WebOS-Internals wiki is still online (albeit with an expired SSL certificate, as of 8 Jan 2022) with a trove of information if you can dig through it, though overall the documentation surrounding hacking on webOS devices seems quite disorganised nowadays across old forum posts and wikis that have managed to survive since 2009.

Broken links are also abound, both as far as old HP/Palm resources go and in terms of community resources. Keep the Wayback Machine handy :)

Contributors

 * thejsa

Porting notes
webOS is built on a downstream Linux 2.6.24 kernel tree, based on TI's OMAP3 flavor. Fortunately however the Pre uses the same SoC as the Nokia N900, which is well supported by postmarketOS and has been mainlined, so this is likely to be a good starting point.

webOS devices are generally considered to be quite hackable, as the flash and bootloader are all accessible over USB using Novacom (see 'How to enter flash mode' below); you can fairly trivially build and boot a custom kernel. It seems that there's no code-signing to get in the way in the boot chain!

How to enter flash mode
Not exactly 'flash mode', per se, but you can send commands (and Linux images!) to the bootloader using Novacom. It's packaged in the Arch Linux AUR, though I haven't tried this distribution of it yet.

In particular, Palm's Bootie bootloader supports booting a kernel sent over USB from memory, see https://www.webos-internals.org/wiki/Memboot.