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Since it seems AI is pretty good at reverse-engineering stuff like this, is there any educational material on how to use it for that purpose? Seems like it could really help port things like postmarketOS to new devices (and improve support on existing ones)?
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> No BSP, no kernel source, no vendor documentation — just a DTB extracted from the stock Android firmware and rebuilt from there. That's exactly how I'd write it, save for the em dash with spaces around it, which is not how em dashes are normally used in English language. I think it's an overreaction.
What? That's exactly how em dashes are used in normal English.
I think surrounding it with spaces comes from people using a regular dash (the em dash is not readily accessible on the keyboard), then surrounding it with spaces to make sure it’s not interpreted as a dash.
What was the motivation for this? Why this particular tablet?
the tablet is cheap and was launched a few years ago, but they still sell it. because it boots from the SD card first, it makes a perfect candidate for this project.
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Pretty much everything. I only had 4GB ram until two or three years ago. No swap. Never ran into an issue.
I have 8GB, which I've had since 2012. Never had a problem - I run a lean Nixos with just xmonad and dmenu, chrome, emacs, and about a dozen open pdfs and video tutorials.
Since I have a desktop I do use rustdesk way more often to just boot into that.
Once the news gets out about epic breakthroughs on commodity hardware and devices, there's unfortunately a likely spike in the purchase cost, even if such devices can be found at all anymore on the usual online sources of new and used goods.
Earlier quoted context omitted.
the tablet is cheap and was launched a few years ago, but they still sell it. because it boots from the SD card first, it makes a perfect candidate for this project.
Did you get it from AliExpress? If so can you post the link to the listing, because I'm not certain that you'll get the same CPU even for the model number.
I reverse-engineered a Doogee U10 (Rockchip RK3562) to boot Debian natively from an SD card. No BSP, no kernel source, no vendor documentation — just a DTB extracted from the stock Android firmware and rebuilt from there. The tablet boots Linux directly from SD without modifying internal Android storage. Remove the card and Android still boots normally. The process is intentionally simple: write the image to an SD ca…
I’m running the risk of just getting an AI response back, but: How are you able to boot Debian from an SD card, and without unlocking the bootloader? Does the bootloader look for an OS on SD card by default? SD and eMMC are basically the same thing, is it just the same lines but an SD card takes priority over the eMMC? And does it not enforce verified boot properly / at all? Maybe being a Rockchip and not MTK/QCOM ha…
But the answer is fairly simple, on a lot of Rockchip devices I’ve used, if there is no SPI flash or custom boot order, the BootROM checks the SD card first and then falls back to eMMC.
That is what happens here. Take the tablet out of the box, write the image to an SD card, insert it, and it boots directly into Linux instead of Android.
So the eMMC Android bootloader can be locked, but it doesn’t matter much if the SoC boots from SD first. Verified boot applies to the Android boot chain on eMMC, not to an external boot path that is accepted earlier by the Rockchip boot flow.
And now you’ll never know if this was an AI answer or not :)
I reverse-engineered a Doogee U10 (Rockchip RK3562) to boot Debian natively from an SD card. No BSP, no kernel source, no vendor documentation — just a DTB extracted from the stock Android firmware and rebuilt from there. The tablet boots Linux directly from SD without modifying internal Android storage. Remove the card and Android still boots normally. The process is intentionally simple: write the image to an SD ca…
> No BSP, no kernel source, no vendor documentation — just a DTB extracted from the stock Android firmware and rebuilt from there. Judging from the build.sh, it looks like this is just using unmodified upstream u-boot and tools from the rockchip-linux repository, so "from scratch" is really just analyzing the DTB to see what drivers need to be loaded?
here the hardware is fixed and undocumented. I didnt modify the tablet, I had to figure out what was inside, what could be supported, where to find missing drivers and how to integrate and debug everything until it actually booted and worked.
I am not claiming to be a C or kernel developer. I am just someone hacking around until the device works. Maybe for others this is trivial, but for me it was a very exciting project.