Hi Ian, On 30/01/14 16:11, Ian Campbell wrote: > mach-virt has existed for a while but it is not written down what it actually > consists of. Although it seems a bit unusual to document a binding for an > entire platform since mach-virt is entirely virtual it is helpful to have > something to refer to in the absence of a single concrete implementation. > > I've done my best to capture the requirements based on the git log and my > memory/understanding. > > While here remove the xenvm dts example, the Xen tools will now build a > suitable mach-virt compatible dts when launching the guest. > > Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx> > Cc: Rob Herring <robh+dt@xxxxxxxxxx> > Cc: Pawel Moll <pawel.moll@xxxxxxx> > Cc: Mark Rutland <mark.rutland@xxxxxxx> > Cc: Kumar Gala <galak@xxxxxxxxxxxxxx> > Cc: Olof Johansson <olof@xxxxxxxxx> > Cc: Arnd Bergmann <arnd@xxxxxxxx> > Cc: Marc Zyngier <marc.zyngier@xxxxxxx> > Cc: Will Deacon <will.deacon@xxxxxxx> > Cc: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx> > Cc: devicetree@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > --- > I'm not sure which tree this sort of thing should go though, sorry for the > huge Cc. > --- > .../devicetree/bindings/arm/mach-virt.txt | 32 ++++++++ > arch/arm/boot/dts/xenvm-4.2.dts | 81 -------------------- > 2 files changed, 32 insertions(+), 81 deletions(-) > create mode 100644 Documentation/devicetree/bindings/arm/mach-virt.txt > delete mode 100644 arch/arm/boot/dts/xenvm-4.2.dts > > diff --git a/Documentation/devicetree/bindings/arm/mach-virt.txt b/Documentation/devicetree/bindings/arm/mach-virt.txt > new file mode 100644 > index 0000000..562bcda > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/mach-virt.txt > @@ -0,0 +1,32 @@ > +* Mach-virt "Dummy Virtual Machine" platform > + > +"mach-virt" is the smallest, dumbest platform possible, to be used as > +a guest for Xen, KVM and other hypervisors. It has no > +properties/functionality of its own and is driven entirely by device > +tree. > + > +This document defines the requirements for such a platform. > + > +* Required properties: > + > +- compatible: should be one of: > + "linux,dummy-virt" > + "xen,xenvm" > + > +In addition to the standard nodes (chosen, cpus, memory etc) the > +platform is required to provide certain other basic functionality > +which must be described in the device tree: > + > + The platform must provide an ARM Generic Interrupt Controller > + (GIC), defined in Documentation/devicetree/bindings/arm/gic.txt. > + > + The platform must provide ARM architected timer, defined in > + Documentation/devicetree/bindings/arm/arch_timer.txt. > + > + If the platform is SMP then it must provide the Power State > + Coordination Interface (PSCI) described in > + Documentation/devicetree/bindings/arm/psci.txt. I'm afraid I disagree with most of the above. The whole point of mach-virt is to provide a shell for DT platforms. None of this hardware is mandated. Instead, all the necessary information should be described in DT. Actually, mach-virt doesn't really stand for Virtual Machine. It stands for virtual mach-* directory! Eventually, mach-virt should become the default platform, the one we use when we don't match anything else in the kernel What you've described here are requirements for a hypervisor like Xen or KVM. mach-virt itself shouldn't have any of that. Cheers, 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@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
