From mboxrd@z Thu Jan 1 00:00:00 1970 From: stefano.stabellini@eu.citrix.com (Stefano Stabellini) Date: Thu, 27 Feb 2014 12:31:55 +0000 Subject: [RFC] ARM VM System Sepcification In-Reply-To: <20140226214843.GD12169@bivouac.eciton.net> References: <20140226183454.GA14639@cbox> <5553754.0b4gMg5OS7@wuerfel> <20140226214843.GD12169@bivouac.eciton.net> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, 26 Feb 2014, Leif Lindholm wrote: > > > no FDT. In this case, the VM implementation must provide ACPI, and > > > the OS must be able to locate the ACPI root pointer through the UEFI > > > system table. > > > > > > For more information about the arm and arm64 boot conventions, see > > > Documentation/arm/Booting and Documentation/arm64/booting.txt in the > > > Linux kernel source tree. > > > > > > For more information about UEFI and ACPI booting, see [4] and [5]. > > > > What's the point of having ACPI in a virtual machine? You wouldn't > > need to abstract any of the hardware in AML since you already know > > what the virtual hardware is, so I can't see how this would help > > anyone. > > The point is that if we need to share any real hw then we need to use > whatever the host has. That's right. I dislike ACPI as much as the next guy, but unfortunately if the host only supports ACPI, the Linux driver for a particular device only works together with ACPI, and you want to assign that device to a VM, then we might be forced to use ACPI to describe it.