SoylentNews is people
SoylentNews
from the you-can-change-more-than-the-battery dept.
Olimex just announced the avaliability of their TERES I DIY laptop. The name is from king of ancient times that ruled in the area of Plovdiv, Bulgaria. Return of the netbook? At least once the products stop being out of stock.
This kit lets you assemble a laptop with quad core Allwinner A64 (64 bit ARM Cortex A53 cores), 1GB RAM, 11.6" inch screen 1366 x 768, 4GB eMMC, WiFi & BT, camera, 7000 mAh battery in just under a Kg. Avaliable in black or white, with US keyboard showing a nice Tux. In the assembly instructions you can see two USB ports, HDMI, 3.5 headphone jack, microSD slot, mic and side speakers. Multiple modular cards to update or fix as needed. No fans. Current price 225 EUR incl VAT.
AC opinion: the RAM is soldered and small for modern times, but it could become a plataform upon which to improve without having to throw away everything. Olimex already lists some ideas for future add ons, like FPGA based Logic Analyzer, in the instructions. All spare parts are listed already in shop, some with PCB files (Open Source Hardware, developed with KiCAD) for those wanting to do custom versions.
(Score: 4, Interesting) by Rich on Saturday February 04 2017, @12:13PM
I had a glance at the specs quite some time ago, but if I remember correctly, that's just some kind of super-supervisor mode on ARM, maybe with some attestation trail registers mixed in. So, if you pick up the boot from reset on, you're free to do whatever you want with it. With a plain Allwinner chip, there shouldn't be much in the way. Note, that for the Raspi, the Videocore blob brings up the ARM, so things might be different there, and recent Intel CPUs refuse to boot anything not signed by Intel.
On a sidenote, I'm quite impressed. Whenever you look for Raspi alternatives, Olimex are somewhere in view. The Bulgarians in general seem to have a good grasp of such stuff. Ages ago, I had a little MP3 player, called "Diva Player" - made in Bulgaria. Neat thing, it cost half of the competition, would run off an AA cell, had a CF slot, and when I wrote them about some incompatibility with classic Mac OS (yes, it was that old), they responded with a fixed firmware.
(Score: 3, Informative) by NCommander on Sunday February 05 2017, @06:06AM
Specifically, and in an ARM64 chip, we're talking about the EL3 mode, or TrustZone*. I did a little work of this when I was involved with UEFI for Linario, but the basic way it works is when the processor comes out of reset, its in EL3, and in TrustZone mode which has some extremely odd rules involved (such as disabling virtual memory, and limiting the operations you can do). If the processor's reset point is in flash, then installing your own EL3 code is possible, but most production chips I've seen lock it to a mask ROM.
The initial EL3 bootstrap (known as a monitor) finishes and usually validates the EL2 boot image (which is the UEFI firwmare blob) and jumps to the entry point. UEFI then boots the kernel. The kernel has the option to install a hook for a hypervisor at the EL2 level, then drops to EL1. Userland applications run at EL0. The practical upshot of this mostly depends if the processor reset point is a place we can write, or if its mask ROM. If the mask ROM simply does a jmp instruction into UEFI, it's de-facto disabled. Not all ARM64 chips have TrustZone and can directly come out of reset in EL1 or 2 depending if the chip supports virtualization. Without an examination of one of the SoCs and a look at its bootstrap code though, I can't honestly say if its possible to change or replace the monitor or even the UEFI image with a home rolled one.
* - TrustZone exists on ARM32 bit chips, but is fairly different in operation as it's a completely different mode vs. an integrated set of the security system.
Still always moving