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diff --git a/docs/hardware/c201.md b/docs/hardware/c201.md new file mode 100644 index 00000000..1aede14a --- /dev/null +++ b/docs/hardware/c201.md @@ -0,0 +1,180 @@ +--- +title: ASUS Chromebook C201 +... + +This is a Chromebook, using the Rockchip RK3288 SoC. It uses an ARM CPU, +and has free EC firmware (unlike some other laptops). More RK3288-based +laptops will be added to libreboot at a later date. + +Paul Kocialkowski, a [Replicant](http://www.replicant.us/) developer, +ported this laptop to libreboot. Thank you, Paul! + +**More info will be added later, including build/installation +instructions. The board is supported in libreboot, however, and has been +confirmed to work.** + +Flashing instructions can be found at +[../install/\#flashrom](../install/#flashrom) + +- [Google's intent with CrOS devices](#googlesintent) +- [Considerations about ChromeOS and free operating systems](#os) +- [Caution: Video acceleration requires a non-free blob, software + rendering can be used instead.](#videoblobs) +- [Caution: WiFi requires a non-free blob, a USB dongle can be used + instead.](#wifiblobs) +- [EC firmware is free software!](#ec) +- [No microcode!](#microcode) +- [Depthcharge payload](#depthcharge) +- [Flash chip write protection: the screw](#thescrew) + +Google's intent with CrOS devices {#googlesintent} +================================== + +CrOS (Chromium OS/Chrome OS) devices, such as Chromebooks, were not +designed with the intent of bringing more freedom to users. However, +they run with a lot of free software at the boot software and embedded +controller levels, since free software gives Google enough flexibility +to optimize various aspects such as boot time and most importantly, to +implement the CrOS security system, that involves various aspects of the +software. Google does hire a lot of Coreboot developers, who are +generally friendly to the free software movement and try to be good +members of the free software community, by contributing code back. + +CrOS devices are designed (from the factory) to actually coax the user +into using proprietary web services (SaaSS) that invade the user's +privacy (ChromeOS is literally just the Google Chrome browser when you +boot up, itself proprietary and comes with proprietary add-ons like +flash. It's only intended for SaaSS, not actual, real computing). +Google is even a member of the *PRISM* program, as outlined by Edward +Snowden. See notes about ChromeOS below. The libreboot project +recommends that the user replace the default *ChromeOS* with a +distribution that can be used in freedom, without invading the user's +privacy. + +We also use a similar argument for the MacBook and the ThinkPads that +are supported in libreboot. Those laptops are supported, in spite of +Apple and Lenovo, companies which are actually *hostile* to the free +software movement. + +Considerations about ChromeOS and free operating systems {#os} +======================================================== + +This laptop comes preinstalled (from the factory) with Google ChromeOS. +This is a GNU+Linux distribution, but it's not general purpose and it +comes with proprietary software. It's designed for SaaSS. Libreboot +recommends that users of this laptop replace it with another +distribution. + +Debian GNU+Linux +---------------- + +<https://wiki.debian.org/InstallingDebianOn/Asus/C201> shows how to +install Debian. + +TODO: instructions for Devuan + +Caution: Video acceleration requires a non-free blob, software rendering can be used instead. {#videoblobs} +============================================================================================= + +The Tamil driver source code for the onboard Mali T GPU is not released. +The developer has so-far withheld it. Until that is released, the only +way to use video (in freedom) on this laptop is to not have video +acceleration, by making sure not to install the relevant blob. Most +tasks can still be performed without video acceleration, without any +noticeable performance penalty. + +In practise, this means that certain things like games, blender and +GNOME shell (or other fancy desktops) won't work well. The libreboot +project recommends a lightweight desktop which does not need video +acceleration, such as *XFCE* or *LXDE*. + +The Tamil developer wrote this blog post, which sheds light on the +story: +[http://libv.livejournal.com/27461.html,http://libv.livejournal.com/27461.html](http://libv.livejournal.com/27461.html). + +Caution: WiFi requires a non-free blob, a USB dongle can be used instead. {#wifiblobs} +========================================================================= + +These laptops have non-removeable (soldered on) WiFi chips, which +require non-free firmware in the Linux kernel in order to work. + +The libreboot project recommends using an external USB wifi dongle that +works with free software. See +[\#recommended\_wifi](./#recommended_wifi). + +There are 2 companies (endorsed by Creative Commons, under their +*Respects your Freedom* guidelines), that sell USB WiFi dongles +guaranteed to work with free software (i.e. linux-libre kernel): + +- [ThinkPenguin sells + them](https://www.thinkpenguin.com/gnu-linux/penguin-wireless-n-usb-adapter-gnu-linux-tpe-n150usb) + (company based in USA) +- [Tehnoetic sells + them](https://tehnoetic.com/tehnoetic-wireless-adapter-gnu-linux-libre-tet-n150) + (company based in Europe) + +These wifi dongles use the AR9271 (atheros) chipset, supported by the +free *ath9k\_htc* driver in the Linux kernel. They work in *linux-libre* +too. + +EC firmware is free software! {#ec} +============================= + +It's free software. Google provides the source. Build scripts will be +added later, with EC sources provided in libreboot, and builds of the EC +firmware. + +This is unlike the other current libreboot laptops (Intel based). In +practise, you can (if you do without the video/wifi blobs, and replace +ChromeOS with a distribution that respects your freedom) be more free +when using one of these laptops. + +The libreboot FAQ briefly describes what an *EC* is: +[../../faq/#firmware-ec](../../faq/#firmware-ec) + +No microcode! {#microcode} +============= + +Unlike x86 (e.g. Intel/AMD) CPUs, ARM CPUs do not use microcode, not +even built in. On the Intel/AMD based libreboot systems, there is still +microcode in the CPU (not considered problematic by the FSF, provided +that it is reasonably trusted to not be malicious, since it's part of +the hardware and read-only), but we exclude microcode updates (volatile +updates which are uploaded at boot time by the boot firmware, if +present), which are proprietary software. + +On ARM CPUs, the instruction set is implemented in circuitry, without +microcode. + +Depthcharge payload {#depthcharge} +=================== + +These systems do not use the GRUB payload. Instead, they use a payload +called depthcharge, which is common on CrOS devices. This is free +software, maintained by Google. + +Flash chip write protection: the screw {#thescrew} +====================================== + +It's next to the flash chip. Unscrew it, and the flash chip is +read-write. Screw it back in, and the flash chip is read-only. It's +called the screw. + +*The screw* is accessible by removing other screws and gently prying off +the upper shell, where the flash chip and the screw are then directly +accessible. User flashing from software is possible, without having to +externally re-flash, but the flash chip is SPI (SOIC-8 form factor) so +you can also externally re-flash if you want to. In practise, you only +need to externally re-flash if you brick the laptop; read +[../install/bbb\_setup.html](../install/bbb_setup.html) for an example +of how to set up an SPI programmer. + +Write protection is useful, because it prevents the firmware from being +re-flashed by any malicious software that might become executed on your +GNU+Linux system, as root. In other words, it can prevent a +firmware-level *evil maid* attack. It's possible to write protect on +all current libreboot systems, but CrOS devices make it easy. The screw +is such a stupidly simple idea, which all designs should implement. + +Copyright © 2015 Leah Rowe <info@minifree.org>\ +This page is available under the [CC BY SA 4.0](../cc-by-sa-4.0.txt) |