From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jookia <166291@gmail.com> Subject: Re: Guix on Mobile (Was: Interest check: U-Boot bootloader support) Date: Tue, 23 Feb 2016 07:29:51 +1100 Message-ID: <20160222202951.GA14346@novena-choice-citizen.lan> References: <20160220204325.GA16645@novena-choice-citizen.lan> <87vb5giupe.fsf@grrlz.net> <87povo8w0k.fsf@dustycloud.org> <20160222191927.GA4900@novena-choice-citizen.lan> <20160222211756.6f286f57@scratchpost.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:43824) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from <166291@gmail.com>) id 1aXx9X-0001QK-PO for guix-devel@gnu.org; Mon, 22 Feb 2016 15:32:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from <166291@gmail.com>) id 1aXx9S-0002Cf-Q2 for guix-devel@gnu.org; Mon, 22 Feb 2016 15:32:19 -0500 Received: from mail-wm0-x22e.google.com ([2a00:1450:400c:c09::22e]:32916) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from <166291@gmail.com>) id 1aXx9S-0002CT-IT for guix-devel@gnu.org; Mon, 22 Feb 2016 15:32:14 -0500 Received: by mail-wm0-x22e.google.com with SMTP id g62so173539882wme.0 for ; Mon, 22 Feb 2016 12:32:14 -0800 (PST) Content-Disposition: inline In-Reply-To: <20160222211756.6f286f57@scratchpost.org> List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org To: Danny Milosavljevic Cc: guix-devel@gnu.org On Mon, Feb 22, 2016 at 09:17:56PM +0100, Danny Milosavljevic wrote: > Hi, Hey! > > Basically the bootloader would just be Linux to do some hardware init (touch screen, etc) > Actually, on ARM you usually have to do basic hardware init before Linux runs. > Linux doesn't do it all. Often, booting Linux without U-Boot doesn't work. > > On linux-sunxi, U-Boot initializes some clocks, memory, important regulators, USB, MMC and the framebuffer (I'm sure I forgot some). > > U-Boot started out as just a tiny copy of Linux, but it has diverged a bit since. This is true, I should've said that it'd go from u-boot -> linux. Rather than, u-boot -> grub -> linux. The advantage here is Linux can do initialization of things like the screen or touchpad. > There are also weird things like you aren't allowed to turn stuff you need later off (in, say, U-Boot), because once it's off, you can't turn it on again (because it's off, duh) without rebooting. So kexeced Linux can find itself in a world of hurt. > > (There's a special data-passing mechanism between U-Boot and Linux in order to mitigate that problem - but does it work between Linux and kexec-Linux?) Not sure you'd need to do that if you're already in a set up Linux? > > systems with GRUB and U-Boot as Linux tends to initialize hardware better than > > them (neither U-Boot nor Libreboot like either of the EDID values of my screen!) > > and would probably allow faster bootup given you're not initializing the > > hardware twice. > > I also have a screen with wrong EDID. I have a DVI<->HDMI adapter by ATI which contains an EDID chip in order to fake the data in order to get it to work. How insane is that? Insane! > That said, on the general interest: guix is already slooow on a fairly modern X200. If that ran on an armv7, it would probably be much slower. Not fun. > > But might be worth a try. Did someone try the non-GuixSD armv7 thing? Is the speed acceptable? I already run NixOS on ARM as my desktop machine, not sure how much slower GuixSD would be. On a phone, though it could be much worse. Jookia.