[Replicant] GNU/Android

Denis 'GNUtoo' Carikli GNUtoo at no-log.org
Mon Dec 14 23:42:44 UTC 2015


On Sun, 13 Dec 2015 09:22:30 +0000
Josh Branning <lovell.joshyyy at gmail.com> wrote:

> I do not expect that all non-touchscreen apps can be used with a touch
> screen, but it's certainly possible to make things 'easier' for the
> user when switching between things. There are several devices now,
> like a laptop, where the keyboard can be detached to make a tablet.
The thing to watch out is if the desktop environments that are friendly
to tablets all require 3D acceleration.

As for 3D acceleration, I don't see the any work to convert LIMA into a
proper upstream driver. This is because Luke had to stop working on it.
He did a wonderful work. Thanks a lot Luke.

Qualcomm drivers are upstream and should work well, some tablets
use a qualcomm SOC that lacks a modem. However that doesn't make such
SOC acceptable due to other freedom issues, such as the lack of free
bootloader.

I think the most promising SOC for 3D and freedom are the I.MX6 ones.
Their GPU has been documented trough reverse engineering, and patches
series are being posted to mainline Linux to support it.

However this SOC is typically used in industrial or automotive
environments. I know no phone nor tablets using it. Given that this SOC
also supports PCIe, ath9k mPCIe cards are possible.
There are power consumption tests here[1], and such card might fit in
tablets. I'm unsure if it's doable to fit one in a phablet.
I've no idea if the power consumption is low enough for a tablet.

Note that the ath9k(and ath5k) supported cards have no fimrware, it's
just hardware and a driver. This architecture is truly wonderful.

Nvidia Tegra are also promising with regard to the Tegra K1, however the
more recent Tegra X1 require some signed fimrwares for the GPU.

As for Replicant we now aim to support devices with free software
bootloader and isolated modem. So I'd expect a GNU/Linux replacement to
be at least as free as that.

Given that we don't have 3D acceleration on such devices, and we
probably won't on the ones using powerVR GPUs, I'm unsure if some phone
friendly GNU/Linux desktop environments could work well enough on such
phones.

The LG optimus black specifications would be the kind of worst case
scenario for GNU/Linux:
-> PowerVR: No 3D acceleration.
-> Capacitive touchscreen without a stylus.
-> 480×800 display (~233 ppi).
-> (512M of RAM.)

So here, the screen is small, the DPI is high, the touchscreen is not
precise, you have no 3D acceleration, and 512M of RAM.

Given how rare are phones with unsigned bootloaders, increasing the
requirements would not be a good idea.

The GTA04 is way better in some respects for that (resistive
touchscreen, way better documentation(only 3D is missing)
and already runs GNU/Linux by default), not everybody can afford it.

The last batch is or will be done soon. If we find the time, we want to
support both phones, and possibly other with free bootloaders in
Replicant. The wifi/bluetooth firmwares issues is still unsolved, since
we know no phones nor tablets with free bootloaders, isolated modem, and
WiFi that works without any non free software/drivers/firmware that
could run Replicant. The OpenMoko FreeRunner is way to slow to run
Replicant.

References:
-----------
[1]https://wireless.wiki.kernel.org/en/users/drivers/ath9k/power-consumption

Denis.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://lists.osuosl.org/pipermail/replicant/attachments/20151215/5ba3f132/attachment.asc>


More information about the Replicant mailing list