Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756249AbcJWI0j (ORCPT ); Sun, 23 Oct 2016 04:26:39 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:33984 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752216AbcJWI0g (ORCPT ); Sun, 23 Oct 2016 04:26:36 -0400 Date: Sun, 23 Oct 2016 10:26:31 +0200 From: LABBE Corentin To: Maxime Ripard Cc: Jean-Francois Moine , robh+dt@kernel.org, mark.rutland@arm.com, wens@csie.org, devicetree@vger.kernel.org, linux@armlinux.org.uk, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] ARM: dt: sun8i-h3: Add sunxi-sid to dts for sun8i-h3 Message-ID: <20161023082631.GA28485@Red> References: <1475660904-7959-1-git-send-email-clabbe.montjoie@gmail.com> <20161005122130.8cc229ff5d4990149956b49c@free.fr> <20161019074016.GA31440@Red> <20161020203654.2erph2mr73yzksla@lukather> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161020203654.2erph2mr73yzksla@lukather> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2252 Lines: 58 On Thu, Oct 20, 2016 at 10:36:54PM +0200, Maxime Ripard wrote: > On Wed, Oct 19, 2016 at 09:40:16AM +0200, LABBE Corentin wrote: > > On Wed, Oct 05, 2016 at 12:21:30PM +0200, Jean-Francois Moine wrote: > > > On Wed, 5 Oct 2016 11:48:24 +0200 > > > Corentin Labbe wrote: > > > > > > > This patch add support for the sunxi-sid driver to the device tree for sun8i-h3. > > > > > > > > Signed-off-by: Corentin Labbe > > > > --- > > > > arch/arm/boot/dts/sun8i-h3.dtsi | 5 +++++ > > > > 1 file changed, 5 insertions(+) > > > > > > > > diff --git a/arch/arm/boot/dts/sun8i-h3.dtsi b/arch/arm/boot/dts/sun8i-h3.dtsi > > > > index 9f58bb4..abfd29c 100644 > > > > --- a/arch/arm/boot/dts/sun8i-h3.dtsi > > > > +++ b/arch/arm/boot/dts/sun8i-h3.dtsi > > > > @@ -211,6 +211,11 @@ > > > > #size-cells = <0>; > > > > }; > > > > > > > > + sid: eeprom@01c14200 { > > > > + compatible = "allwinner,sun7i-a20-sid"; > > > > + reg = <0x01c14200 0x200>; > > > > > > The datasheet says 1Kb starting at 0x01c14000. > > > Is there any reason to reduce the area and to shift the offset? > > > > > > > According to http://linux-sunxi.org/SID_Register_Guide "For > > Allwinner A83T and H3 the SID address space starts at 0x01c14000, > > and the e-fuses are at offset 0x200". > > > > So I use this offset, since the sunxi_sid driver need the base > > address of e-fuses. > > > > The easiest solution is to use 0x01c14200 since the other part of > > sid is not used and not known (A83T/H3 user manual doesnt give any > > information on all sid space, worse for A64 which reference SID only > > in memory map). > > > > So probably for H3/A64/A83T, there will never any usage of the rest > > of the SID address space. > > And since we can't know that, and we have to maintain the DT ABI, > using the whole address map and an offset, with a new compatible, is > definetely the safest thing to do. > I have two way of doing it, which one do you prefer ? - Adding two optionnal properties: efuses-offset and efuses-size defaulting to 0 and resourcesize. - Adding a subnode called efuses with its own reg=<> The first one is easy and didnt need any work on previous DT entries. Regards Corentin Labbe