From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH 2/3] arm64: dts: add the Alpine v2 EVP Date: Tue, 9 Feb 2016 09:30:29 +0000 Message-ID: <56B9B1B5.5070106@arm.com> References: <1454922699-16785-1-git-send-email-antoine.tenart@free-electrons.com> <1454922699-16785-3-git-send-email-antoine.tenart@free-electrons.com> <56B8B45D.1020902@arm.com> <20160209085633.GA5388@kwain> <20160209090131.GB5388@kwain> <56B9ACE2.1060200@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Tsahee Zidenberg Cc: Antoine Tenart , catalin.marinas-5wv7dgnIgG8@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , Ronen Shitrit , Thomas Petazzoni , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Barak Wasserstrom List-Id: devicetree@vger.kernel.org On 09/02/16 09:14, Tsahee Zidenberg wrote: > > > On 9 February 2016 at 11:09, Marc Zyngier > wrote: > > On 09/02/16 09:01, Antoine Tenart wrote: > > On Tue, Feb 09, 2016 at 09:56:33AM +0100, Antoine Tenart wrote: > >> Hi Marc, > >> > >> On Mon, Feb 08, 2016 at 03:29:33PM +0000, Marc Zyngier wrote: > >>> On 08/02/16 09:11, Antoine Tenart wrote: > >>> > >>>> + gic: gic@f0100000 { > >>>> + compatible = "arm,gic-v3"; > >>>> + reg = <0x0 0xf0200000 0x0 0x10000>, /* GIC Dist */ > >>>> + <0x0 0xf0280000 0x0 0x200000>, /* GICR */ > >>>> + <0x0 0xf0100000 0x0 0x2000>; /* GICC */ > >>>> + interrupt-controller; > >>>> + #interrupt-cells = <3>; > >>>> + }; > >>> > >>> Something is wrong here. Either you are missing GICH and GICV (assuming > >>> you have legacy support), or you have an extra GICC region (which > >>> doesn't make sense on its own). > >> > >> I'll add the missing regions. > > > > Hmm, in fact the GICC region shouldn't be there. I'll make some tests > > and remove it. > > If you have a GICv3 with legacy support, you will probably have GICC, > GICH and GICV. Linux itself will only use GICD and GICR, but it needs at > least GICV to be able to virtualize GICv2 guests. And GICV is not > allowed to exist without GICC and GICH, so I really recommend that you > keep GICC around. > > > We use the GIC without legacy support (we disable it in early boot > stages), so I think removing the GICC region is the better solution. Disabling legacy support doesn't mean that: - the HW isn't present - the associated regions are not useful Here, we describe the HW, not the usage you make of it. And unless you think that having working virtualization is completely useless, I strongly suggest that you properly document the HW in the device tree. Thanks, M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html