Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934442Ab2JXHo3 (ORCPT ); Wed, 24 Oct 2012 03:44:29 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:54780 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934420Ab2JXHo1 (ORCPT ); Wed, 24 Oct 2012 03:44:27 -0400 Message-ID: <50879C4E.6020003@ti.com> Date: Wed, 24 Oct 2012 09:44:14 +0200 From: Benoit Cousson Organization: Texas Instruments User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: Sebastien Guiriec CC: Jon Hunter , Tony Lindgren , , , Santosh Shilimkar , , Subject: Re: [PATCH v2 1/4] ARM: dts: omap5: Update GPIO with address space and interrupts References: <1350981432-6750-1-git-send-email-s-guiriec@ti.com> <1350981432-6750-2-git-send-email-s-guiriec@ti.com> <5086AE8E.60106@ti.com> <5086B316.6000001@ti.com> <5086BECA.9070502@ti.com> <5086C0C3.1060305@ti.com> <5086C29C.5000209@ti.com> In-Reply-To: <5086C29C.5000209@ti.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3725 Lines: 94 On 10/23/2012 06:15 PM, Sebastien Guiriec wrote: > Hi Benoit and John, > > On 10/23/2012 06:07 PM, Benoit Cousson wrote: >> On 10/23/2012 05:59 PM, Jon Hunter wrote: >>> >>> On 10/23/2012 10:09 AM, Benoit Cousson wrote: >>>> On 10/23/2012 04:49 PM, Jon Hunter wrote: >>>>> Hi Seb, >>>>> >>>>> On 10/23/2012 03:37 AM, Sebastien Guiriec wrote: >>>>>> Add base address and interrupt line inside Device Tree data for >>>>>> OMAP5 >>>>>> >>>>>> Signed-off-by: Sebastien Guiriec >>>>>> --- >>>>>> arch/arm/boot/dts/omap5.dtsi | 16 ++++++++++++++++ >>>>>> 1 file changed, 16 insertions(+) >>>>>> >>>>>> diff --git a/arch/arm/boot/dts/omap5.dtsi >>>>>> b/arch/arm/boot/dts/omap5.dtsi >>>>>> index 42c78be..9e39f9f 100644 >>>>>> --- a/arch/arm/boot/dts/omap5.dtsi >>>>>> +++ b/arch/arm/boot/dts/omap5.dtsi >>>>>> @@ -104,6 +104,8 @@ >>>>>> >>>>>> gpio1: gpio@4ae10000 { >>>>>> compatible = "ti,omap4-gpio"; >>>>>> + reg = <0x4ae10000 0x200>; >>>>>> + interrupts = <0 29 0x4>; >>>>>> ti,hwmods = "gpio1"; >>>>>> gpio-controller; >>>>>> #gpio-cells = <2>; >>>>> >>>>> I am wondering if we should add the "interrupt-parent" property to add >>>>> nodes in the device-tree source. I know that today the >>>>> interrupt-parent >>>>> is being defined globally, but when device-tree maps an interrupt >>>>> for a >>>>> device it searches for the interrupt-parent starting the current >>>>> device >>>>> node. >>>>> >>>>> So in other words, for gpio1 it will search the gpio1 binding for >>>>> "interrupt-parent" and if not found move up a level and search >>>>> again. It >>>>> will keep doing this until it finds the "interrupt-parent". >>>>> >>>>> Therefore, I believe it will improve search time and hence, boot >>>>> time if >>>>> we have interrupt-parent defined in each node. >>>> >>>> Mmm, I'm not that sure. it will increase the size of the blob, so >>>> increase the time to load it and then to parse it. Where in the current >>>> case, it is just going up to the parent node using the already >>>> un-flatten tree in memory and thus that should not take that much time. >>> >>> Yes it will definitely increase the size, so that could slow things >>> down. >>> >>>> That being said, it might be interesting to benchmark that to see what >>>> is the real impact. >>> >>> Right, I wonder what the key functions are we need to benchmark to get >>> an overall feel for what is best? Right now I am seeing some people add >>> the interrupt-parent for device nodes and others not. Ideally we should >>> be consistent, but at the same time it is probably something that we can >>> easily sort out later. So not a big deal either way. >> >> For consistency, I'd rather not add it at all for the moment. >> Later, when we will only support DT boot, people will start complaining >> about the boot time increase and then we will start optimizing a little >> bit :-) > > I just do it like that to be consistent with what is inside OMAP4 dtsi > for those IPs (GPIO/UART/MMC/I2C). Now after checking Peter already add > the interrupt-parent for all audio IPs (OMAP3/4/5). But here we need > also interrupts name. So here we should try to be consistent. > > So I can send back the series for OMAP5 and update the OMAP4 with > interrupts-parent = <&gic> No, you should not, as explained previously. You'd better remove the one already in audio IPs for consistency. Regards, Benoit -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/