From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liviu Dudau Subject: Re: [PATCH 3/4] arm64: Juno: Add support for the PCIe host bridge on Juno R1 Date: Fri, 9 Oct 2015 17:09:10 +0100 Message-ID: <20151009160910.GF3394@e106497-lin.cambridge.arm.com> References: <1444398323-17354-1-git-send-email-Liviu.Dudau@arm.com> <20151009141107.GD3394@e106497-lin.cambridge.arm.com> <20151009154408.GD21629@leverpostej> <40550712.xdsq5nNSTG@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <40550712.xdsq5nNSTG@wuerfel> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Mark Rutland , Jon Medhurst , Ian Campbell , linux-pci , Linus Walleij , Kumar Gala , Will Deacon , LKML , device-tree , Rob Herring , Catalin Marinas , Bjorn Helgaas , Robin Murphy List-Id: devicetree@vger.kernel.org On Fri, Oct 09, 2015 at 05:49:18PM +0200, Arnd Bergmann wrote: > On Friday 09 October 2015 16:44:08 Mark Rutland wrote: > > On Fri, Oct 09, 2015 at 03:11:07PM +0100, Liviu Dudau wrote: > > > On Fri, Oct 09, 2015 at 08:54:33AM -0500, Rob Herring wrote: > > > Or maybe I can claim the use of the string on account on being th= e first on arm64=20 > > >=20 > > > I can add a vendor prefix if you want, but pci-host-generic is go= ing to ignore it=20 > > > *because* it is trying to be a generic driver. > >=20 > > The point here is to have the string ready if we need it later, so = it's > > fine that it's not used currently. > >=20 > > Rob's suggestion is that the compatible list should look something = like: > >=20 > > compatible =3D "arm,juno-r1-pcie", "plda,xpressrich3", "pci-host-ec= am-generic"; > >=20 > > We can match on "pci-host-ecam-generic" for now (and hopefully fore= ver), > > but if for some reason we need to special-case this host controller= (or > > Juno's integration thereof), we can do that based on the compatible > > string. >=20 > Sounds good to me, it certainly can't hurt. >=20 > Arnd Hmm, I'm sorry, but this time I'm going to disagree. I understand the principle that the DTS is a description of the hardwar= e and it should not have any built in knowledge of how a driver works but describe the = physical properties of the device (where such description makes sense, in this case it does= ). However, when ARM has created the Juno platform it has also created a s= tandard called SBSA and has claimed that Juno is compliant with that standard. My curr= ent position (and it used to be MarkR's as well when we have argued internally the pros a= nd cons of having a bespoke driver for PLDA's XpressRICH3) is that SBSA compliant behavio= ur *is* the expected behaviour and if the device doesn't conform it needs to be fixed in fir= mware. Otherwise, I could've posted months ago the other public driver[1] that= I've wrote that doesn't depend on firmware and could have been done with this long time= ago. Best regards, Liviu 1. https://github.com/ARM-software/linux/commit/ca9d82679916c3b6bdb8463= 19e343a43a6bbb31c > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" = in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >=20 --=20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- =C2=AF\_(=E3=83=84)_/=C2=AF -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html