From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Unable to boot mainline on snow chromebook since 3.15 Date: Fri, 5 Sep 2014 12:57:04 +0100 Message-ID: <20140905115704.GO13515@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:42150 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932096AbaIEL4u (ORCPT ); Fri, 5 Sep 2014 07:56:50 -0400 Content-Disposition: inline Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: kgene.kim@samsung.com, olof@lixom.net, dianders@chromium.org, rahul.sharma@samsung.com Cc: linux-arm-kernel@lists-infradead.org, linux-samsung-soc@vger.kernel.org Hi all, I'm one of the few, foolish people to try running mainline on my 5250-based Samsung Chromebook (snow). I can live without wireless, usb3 and video acceleration, so actually it makes a reasonable development platform for doing A15-based (micro)-architectural work. However, since 3.15 I've not been able to boot *any* mainline kernels on this board. I did mean to report this earlier, but I have other machines that can run mainline so this has fallen by the wayside. The problems started with 3.16, where simple-fb would fail to initialise and I lost my display. Note that I don't have a serial console on this machine (I looked at the PCB and there's no way I can solder one of those myself :) I bisected the issue at the time, and I could get my display back by removing some of the new regulator and hdmi properties from the DT. At that point, I could boot, but DMA didn't initialise for the MMC controller so I couldn't mount my root filesystem. With 3.17-rc3, it seems a lot worse -- I don't get any output after nv-uboot (i.e. the nv-uboot screen just remains on the display, with the last line reading "Stashed 20 records"). I'd usually try to debug this a bit further, but without a console it's really painful to get anywhere. I've been working with 3.15, but now I'm having to backport patches when I want to test them, which is more effort than I can be bothered with. Is anybody else running mainline on this device and are these known/fixed problems? Cheers, Will