From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38192) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XoX1a-0000bd-HT for qemu-devel@nongnu.org; Wed, 12 Nov 2014 07:27:56 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XoX1U-0000te-CV for qemu-devel@nongnu.org; Wed, 12 Nov 2014 07:27:50 -0500 Received: from mx1.redhat.com ([209.132.183.28]:47617) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XoX1U-0000tC-0R for qemu-devel@nongnu.org; Wed, 12 Nov 2014 07:27:44 -0500 Message-ID: <54635222.5000700@redhat.com> Date: Wed, 12 Nov 2014 13:27:14 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1414691045-4793-1-git-send-email-a.spyridakis@virtualopensystems.com> <546323A7.6040805@huawei.com> <20141112105640.GB28015@leverpostej> <1857764.BysEu3dgOQ@wuerfel> <20141112113401.GH19598@cbox> <5463490B.9080101@redhat.com> <20141112121809.GF28015@leverpostej> In-Reply-To: <20141112121809.GF28015@leverpostej> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [Linaro-acpi] [RFC PATCH 0/7] hw/arm/virt: Dynamic ACPI v5.1 table generation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mark Rutland Cc: Peter Maydell , Arnd Bergmann , "linaro-acpi@lists.linaro.org" , Paul Mundt , Claudio Fontana , QEMU Developers , Jani Kokkonen , "tech@virtualopensystems.com" , Christoffer Dall On 12/11/2014 13:18, Mark Rutland wrote: > On Wed, Nov 12, 2014 at 11:48:27AM +0000, Paolo Bonzini wrote: >> >> On 12/11/2014 12:34, Christoffer Dall wrote: >>> AFAIU ACPI already has a method for doing this >> >> It's not defined in the spec. QEMU defines a bunch of registers to do >> that, and provides AML that works with those registers. > > Huh? SCI + AML is the method, and that's defined by the spec. I thought Christoffer meant a method to do the actual hotplug, not just to signal events. If you want to "support the low-level interfaces in the kernel for this anyway", you certainly need to know the details underneath the AML. >> Perhaps you could treat it as a shared level-triggered interrupt in DT? >> I don't know. > > Putting an interrupt in DT is trivial. The hard part is the rest of the > interface, which so far there is no specification for. Have you looked at docs/specs/acpi_{cpu,mem}_hotplug.txt? Writing a DT binding for it is trivial too. Or are we talking about two different things? Paolo