From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from compulab.co.il (compulab.co.il [67.18.134.219]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 7F8E91007D2 for ; Wed, 16 Jun 2010 17:02:53 +1000 (EST) Message-ID: <4C186AA8.4040709@compulab.co.il> Date: Wed, 16 Jun 2010 09:09:44 +0300 From: Mike Rapoport MIME-Version: 1.0 To: Mitch Bradley Subject: Re: Request review of device tree documentation References: <4C13430B.5000907@firmworks.com> <1276339529.1962.184.camel@pasglop> <1276339684.1962.186.camel@pasglop> <4C13B618.1030006@firmworks.com> <1276383132.1962.195.camel@pasglop> <4C146F18.9030008@firmworks.com> <20100614124438.GF9323@yookeroo> <20100614160201.GD9550@shareable.org> <4C165FD1.6080505@firmworks.com> In-Reply-To: <4C165FD1.6080505@firmworks.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: Nicolas Pitre , microblaze-uclinux@itee.uq.edu.au, devicetree-discuss , Jamie Lokier , linuxppc-dev , Mike Rapoport , Dan Malek , Jeremy Kerr , linux-arm-kernel@lists.infradead.org, David Gibson List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Mitch Bradley wrote: > The second topic is the hypothetical use of OFW as a HAL. That will not > happen for several reasons. The opposition to the idea is widespread > and deeply held, and there are good arguments to support that > opposition. Furthermore, the economic conditions necessary for the > creation of such a HAL do not exist in the ARM world, nor indeed in the > Linux world in general. (The necessary condition is the ability for one > company to impose a substantial change by fiat - essentially a monopoly > position.) > > Shall we agree, then, that any further discussion of the HAL issue is > "just for fun", and that nobody needs to feel threatened that it would > actually happen? I've recently worked with vendor versions of U-Boot for advanced ARM SoCs. There is already *huge* chunk of HAL code in those versions. And if there would be possibility to have callbacks into the firmware these chunks would only grow, IMHO. > The potential for "vendors breaking out of the debugging use case and > turning it into a HAL" is miniscule, because > > a) The callback is disabled by default > b) The technical challenges of the callback interface limit its > applicability to specific "wizard user" scenarios > c) OFW is unlikely to achieve sufficient market penetration for the HAL > thing to be worth doing > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Sincerely yours, Mike. From mboxrd@z Thu Jan 1 00:00:00 1970 From: mike@compulab.co.il (Mike Rapoport) Date: Wed, 16 Jun 2010 09:09:44 +0300 Subject: Request review of device tree documentation In-Reply-To: <4C165FD1.6080505@firmworks.com> References: <4C13430B.5000907@firmworks.com> <1276339529.1962.184.camel@pasglop> <1276339684.1962.186.camel@pasglop> <4C13B618.1030006@firmworks.com> <1276383132.1962.195.camel@pasglop> <4C146F18.9030008@firmworks.com> <20100614124438.GF9323@yookeroo> <20100614160201.GD9550@shareable.org> <4C165FD1.6080505@firmworks.com> Message-ID: <4C186AA8.4040709@compulab.co.il> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Mitch Bradley wrote: > The second topic is the hypothetical use of OFW as a HAL. That will not > happen for several reasons. The opposition to the idea is widespread > and deeply held, and there are good arguments to support that > opposition. Furthermore, the economic conditions necessary for the > creation of such a HAL do not exist in the ARM world, nor indeed in the > Linux world in general. (The necessary condition is the ability for one > company to impose a substantial change by fiat - essentially a monopoly > position.) > > Shall we agree, then, that any further discussion of the HAL issue is > "just for fun", and that nobody needs to feel threatened that it would > actually happen? I've recently worked with vendor versions of U-Boot for advanced ARM SoCs. There is already *huge* chunk of HAL code in those versions. And if there would be possibility to have callbacks into the firmware these chunks would only grow, IMHO. > The potential for "vendors breaking out of the debugging use case and > turning it into a HAL" is miniscule, because > > a) The callback is disabled by default > b) The technical challenges of the callback interface limit its > applicability to specific "wizard user" scenarios > c) OFW is unlikely to achieve sufficient market penetration for the HAL > thing to be worth doing > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Sincerely yours, Mike. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: Re: Request review of device tree documentation Date: Wed, 16 Jun 2010 09:09:44 +0300 Message-ID: <4C186AA8.4040709@compulab.co.il> References: <4C13430B.5000907@firmworks.com> <1276339529.1962.184.camel@pasglop> <1276339684.1962.186.camel@pasglop> <4C13B618.1030006@firmworks.com> <1276383132.1962.195.camel@pasglop> <4C146F18.9030008@firmworks.com> <20100614124438.GF9323@yookeroo> <20100614160201.GD9550@shareable.org> <4C165FD1.6080505@firmworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4C165FD1.6080505@firmworks.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Mitch Bradley Cc: Nicolas Pitre , microblaze-uclinux@itee.uq.edu.au, devicetree-discuss , Jamie Lokier , Grant Likely , linuxppc-dev , Mike Rapoport , Dan Malek , Jeremy Kerr , linux-arm-kernel@lists.infradead.org, David Gibson List-Id: devicetree@vger.kernel.org Mitch Bradley wrote: > The second topic is the hypothetical use of OFW as a HAL. That will not > happen for several reasons. The opposition to the idea is widespread > and deeply held, and there are good arguments to support that > opposition. Furthermore, the economic conditions necessary for the > creation of such a HAL do not exist in the ARM world, nor indeed in the > Linux world in general. (The necessary condition is the ability for one > company to impose a substantial change by fiat - essentially a monopoly > position.) > > Shall we agree, then, that any further discussion of the HAL issue is > "just for fun", and that nobody needs to feel threatened that it would > actually happen? I've recently worked with vendor versions of U-Boot for advanced ARM SoCs. There is already *huge* chunk of HAL code in those versions. And if there would be possibility to have callbacks into the firmware these chunks would only grow, IMHO. > The potential for "vendors breaking out of the debugging use case and > turning it into a HAL" is miniscule, because > > a) The callback is disabled by default > b) The technical challenges of the callback interface limit its > applicability to specific "wizard user" scenarios > c) OFW is unlikely to achieve sufficient market penetration for the HAL > thing to be worth doing > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- Sincerely yours, Mike.