From mboxrd@z Thu Jan 1 00:00:00 1970 From: dannym@scratchpost.org (Danny Milosavljevic) Date: Tue, 9 Feb 2016 21:33:21 +0100 Subject: [linux-sunxi] Re: [PATCH 11/11] arm64: dts: add Pine64 support In-Reply-To: References: <1454348370-3816-1-git-send-email-andre.przywara@arm.com> <1454348370-3816-12-git-send-email-andre.przywara@arm.com> <20160205090337.GB1139@lukather> <56B47391.1040709@arm.com> Message-ID: <20160209213321.7ab6beba@scratchpost.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, On Mon, 8 Feb 2016 11:55:43 +1100 Julian Calaby wrote: > I believe that device tree overlays are the generally recommended method. I agree. But last time I tried, the device tree compiler didn't support overlays - neither in Debian nor in the in-kernel dtc ("-@" is unsupported; last tried with linux-4.3-rc7). And even if you could compile them, the platform has to support specifying which overlays to use in the first place (for example as a Linux cmdline option). For example Beaglebone Black (TI Sitara) does. I don't know whether sunxi does. Also, the overlay dts files are very different from normal dts files, see . The original Linux device tree changeset patchset also introduced an in-kernel interface for loading/unloading of DT overlays at runtime. AFAIK, this is still not available to user space. More info at . (I tried some 4 months ago - it wasn't integrated enough. So now I just patch the main dts every time - which I probably shouldn't) Regards, Danny