From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: Re: [PATCH] help guest boot up on AArch64 host with GICv2 Date: Fri, 29 Jan 2016 18:55:44 +0000 Message-ID: <56ABB5B0.4090900@arm.com> References: <56995068.9050207@ezchip.com> <569CB034.1060307@arm.com> <56A7DA7C.8090202@ezchip.com> <56A88A0E.40002@arm.com> <56AA7618.8030406@ezchip.com> <56ABA74A.3080500@arm.com> <56ABAF80.4090400@ezchip.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 910CC40B40 for ; Fri, 29 Jan 2016 13:50:41 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id kUxieKM3ESdP for ; Fri, 29 Jan 2016 13:50:40 -0500 (EST) Received: from foss.arm.com (foss.arm.com [217.140.101.70]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4DE66407A0 for ; Fri, 29 Jan 2016 13:50:40 -0500 (EST) In-Reply-To: <56ABAF80.4090400@ezchip.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Chris Metcalf , Christoffer Dall , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu List-Id: kvmarm@lists.cs.columbia.edu On 29/01/16 18:29, Chris Metcalf wrote: > On 01/29/2016 12:54 PM, Marc Zyngier wrote: >> By the look of it, you're trying to use a GICv3 firmware, and pass a >> GICv2 DT to the kernel. Do not do that. Either you use a GICv2 firmware >> (having spoken to the ATF guys, there is a GICv2 driver in there that >> should work for your case) and pass a GICv2 DT, or you go GICv3 all the way. >> >> A mix of the two things is completely unsupported on the model, and >> solidly places you in the UNPREDICTABLE category when running that on >> actual HW... > > Once we upgrade to ATF 1.2 we will remove all of our GICv2 > stuff and see if everything works smoothly; till then, at least, we > seem to have a workaround in place for development that will > let us keep moving forward. > > From the ATF docs it does seem that using a v3 GIC in v2 > compatibility mode should be supported, but it's not pressing > from our side to drill any deeper to try to see why it's not > actually working correctly for us (though I'd be happy to try > any further testing in this configuration if that's helpful). That's what I've been told as well - the GICv2 code in ATF 1.2 should do the trick out of the box. Thanks, M. -- Jazz is not dead. It just smells funny... From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Fri, 29 Jan 2016 18:55:44 +0000 Subject: [PATCH] help guest boot up on AArch64 host with GICv2 In-Reply-To: <56ABAF80.4090400@ezchip.com> References: <56995068.9050207@ezchip.com> <569CB034.1060307@arm.com> <56A7DA7C.8090202@ezchip.com> <56A88A0E.40002@arm.com> <56AA7618.8030406@ezchip.com> <56ABA74A.3080500@arm.com> <56ABAF80.4090400@ezchip.com> Message-ID: <56ABB5B0.4090900@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 29/01/16 18:29, Chris Metcalf wrote: > On 01/29/2016 12:54 PM, Marc Zyngier wrote: >> By the look of it, you're trying to use a GICv3 firmware, and pass a >> GICv2 DT to the kernel. Do not do that. Either you use a GICv2 firmware >> (having spoken to the ATF guys, there is a GICv2 driver in there that >> should work for your case) and pass a GICv2 DT, or you go GICv3 all the way. >> >> A mix of the two things is completely unsupported on the model, and >> solidly places you in the UNPREDICTABLE category when running that on >> actual HW... > > Once we upgrade to ATF 1.2 we will remove all of our GICv2 > stuff and see if everything works smoothly; till then, at least, we > seem to have a workaround in place for development that will > let us keep moving forward. > > From the ATF docs it does seem that using a v3 GIC in v2 > compatibility mode should be supported, but it's not pressing > from our side to drill any deeper to try to see why it's not > actually working correctly for us (though I'd be happy to try > any further testing in this configuration if that's helpful). That's what I've been told as well - the GICv2 code in ATF 1.2 should do the trick out of the box. Thanks, M. -- Jazz is not dead. It just smells funny...