Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755373AbcCXBsv (ORCPT ); Wed, 23 Mar 2016 21:48:51 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:36764 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751117AbcCXBss (ORCPT ); Wed, 23 Mar 2016 21:48:48 -0400 Subject: Re: [PATCH 04/12] ARM: dts: dragonboard-600c: add board support with serial To: Bjorn Andersson , Srinivas Kandagatla References: <1458762366-9233-1-git-send-email-srinivas.kandagatla@linaro.org> <1458762442-9492-1-git-send-email-srinivas.kandagatla@linaro.org> <56F2F78E.8050002@codeaurora.org> <56F2FCD0.1000708@linaro.org> Cc: Andy Gross , linux-arm-msm , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, lkml , linux-soc@vger.kernel.org From: Stephen Boyd X-Enigmail-Draft-Status: N1110 Message-ID: <56F3477E.8090205@codeaurora.org> Date: Wed, 23 Mar 2016 18:48:46 -0700 User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2628 Lines: 62 On 03/23/2016 06:04 PM, Bjorn Andersson wrote: > On Wed, Mar 23, 2016 at 1:30 PM, Srinivas Kandagatla > wrote: >> >> On 23/03/16 20:07, Stephen Boyd wrote: >>> On 03/23/2016 12:47 PM, Srinivas Kandagatla wrote: >>>> diff --git a/arch/arm/boot/dts/qcom-apq8064-dragonboard-600c.dts >>>> b/arch/arm/boot/dts/qcom-apq8064-dragonboard-600c.dts >>>> new file mode 100644 >>>> index 0000000..e96aab6 >>>> --- /dev/null >>>> +++ b/arch/arm/boot/dts/qcom-apq8064-dragonboard-600c.dts >>>> @@ -0,0 +1,36 @@ >>>> +#include "qcom-apq8064-v2.0.dtsi" >>>> + >>>> +/ { >>>> + model = "Qualcomm Technologies, Inc. APQ8064 DragonBoard600c"; >>>> + compatible = "qcom,apq8064-dragonboard600c", "qcom,apq8064"; >>> >>> Does the bootloader look at this string at all or is it using appended >>> DTB design? I'm mostly worried about having that >> Not at least on APQ8064 bootloaders, as they are still missing DT support. >> Currently we append dtb to the kernel. >>> qcom,apq8064-dragonboard600c part. It should probably be >>> qcom,apq8064-sbc or something like that instead. >> Will do that in next version. >> > This "sbc" isn't that just the abbreviation for "single board > computer"? I find it hard to believe this is _the_ 8064 sbc or the > only 8064 sbc. I don't make up the names, but for other qcom sbc products the bootloader is looking for sbc there to make sure it picks the right dtb blob. So I guess this is _the_ qcom 8064 sbc? Definitely not _the_ 8064 sbc though. If this device won't get those bootloaders that look for this then it doesn't really matter and I don't care what this is named. Please take a look at Documentation/devicetree/bindings/arm/qcom.txt for what I'm talking about though. > > Also, if I make a product based of this board, with some minor > changes, is that still the sbc? > > I think the compatible should be "qcom,apq8064-db600c", > "qcom,apq8064-sbc", "qcom,apq8064" > > I really hope that people don't keep using the qcom bootloader dtb picking design if they make a new product based off qcom boards with a slight variation. They should replace the vendor part of the compatible anyway with their own vendor prefix, and then the bootloader would need to be updated to look for that string or something else. I really don't want to get in the business of updating dtbTool for all the non-qcom designs that pop up because they keep using the qcom dtb identification scheme. It almost doesn't scale right now and that's just qcom designs. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project