[PATCH] arm: introduce a DTS for Xen unprivileged virtual machines

[Stefano Stabellini]

On Thu, 20 Sep 2012, Rob Herring wrote:
> On 09/19/2012 12:44 PM, Stefano Stabellini wrote:
> > Signed-off-by: Stefano Stabellini <stefano.stabellini at eu.citrix.com>
> > CC: Pawel Moll <pawel.moll at arm.com>
> > CC: linux-arm-kernel at lists.infradead.org
> > ---
> >  arch/arm/boot/dts/vexpress-xenvm-4.2.dts |  115 ++++++++++++++++++++++++++++++
> >  arch/arm/mach-vexpress/Makefile.boot     |    3 +-
> >  2 files changed, 117 insertions(+), 1 deletions(-)
> >  create mode 100644 arch/arm/boot/dts/vexpress-xenvm-4.2.dts
> > 
> > diff --git a/arch/arm/boot/dts/vexpress-xenvm-4.2.dts b/arch/arm/boot/dts/vexpress-xenvm-4.2.dts
> > new file mode 100644
> > index 0000000..bfb802c
> > --- /dev/null
> > +++ b/arch/arm/boot/dts/vexpress-xenvm-4.2.dts
> > @@ -0,0 +1,115 @@
> > +/*
> > + * Xen Virtual Machine for unprivileged guests
> > + *
> > + * Based on ARM Ltd. Versatile Express CoreTile Express (single CPU)
> > + * Cortex-A15 MPCore (V2P-CA15)
> > + *
> > + */
> > +
> > +/dts-v1/;
> > +
> > +/include/ "skeleton.dtsi"
> > +
> > +/ {
> > +	model = "XENVM-4.2";
> > +	compatible = "xen,xenvm-4.2", "arm,vexpress";
> > +	interrupt-parent = <&gic>;
> > +
> > +	chosen {
> > +		bootargs = "earlyprintk console=hvc0 root=/dev/xvda init=/sbin/init";
> > +	};
> > +
> > +	cpus {
> > +		#address-cells = <1>;
> > +		#size-cells = <0>;
> > +
> > +		cpu at 0 {
> > +			device_type = "cpu";
> > +			compatible = "arm,cortex-a15";
> > +			reg = <0>;
> > +		};
> > +	};
> > +
> > +	memory {
> > +		device_type = "memory";
> > +		reg = <0x80000000 0x08000000>;
> 
> How much guest memory can be supported here?

There are no particular restrictions other than the amount of memory
present on the physical hardware and the memory already used by other
guests.


> I would expect something like the memory size to be filled in by the
> hypervisor. If so, perhaps a note on any fields hypervisor will adjust.
> 

Yes, that's a good idea. Certainly the amount of memory would be
adjusted by the hypervisor. Also the properties of the hypervisor node
and maybe the bootargs could be adjusted too.


> > +	};
> > +
> > +	gic: interrupt-controller at 2c001000 {
> > +		compatible = "arm,cortex-a9-gic";
> > +		#interrupt-cells = <3>;
> > +		#address-cells = <0>;
> > +		interrupt-controller;
> > +		reg = <0x2c001000 0x1000>,
> > +		      <0x2c002000 0x100>;
> > +	};
> > +
> > +	timer {
> > +		compatible = "arm,armv7-timer";
> > +		interrupts = <1 13 0xf08>,
> > +			     <1 14 0xf08>,
> > +			     <1 11 0xf08>,
> > +			     <1 10 0xf08>;
> > +	};
> > +
> > +	hypervisor {
> > +		compatible = "xen,xen-4.2", "xen,xen";
> > +		reg = <0xb0000000 0x20000>;
> > +		interrupts = <1 15 0xf08>;
> > +	};
> > +
> > +	motherboard {
> > +		arm,v2m-memory-map = "rs1";
> > +		ranges = <0 0 0x08000000 0x04000000>,
> > +			 <1 0 0x14000000 0x04000000>,
> > +			 <2 0 0x18000000 0x04000000>,
> > +			 <3 0 0x1c000000 0x04000000>,
> > +			 <4 0 0x0c000000 0x04000000>,
> > +			 <5 0 0x10000000 0x04000000>;
> > +
> > +		interrupt-map-mask = <0 0 63>;
> > +		interrupt-map = <0 0  0 &gic 0  0 4>,
> > +				<0 0  1 &gic 0  1 4>,
> > +				<0 0  2 &gic 0  2 4>,
> > +				<0 0  3 &gic 0  3 4>,
> > +				<0 0  4 &gic 0  4 4>,
> > +				<0 0  5 &gic 0  5 4>,
> > +				<0 0  6 &gic 0  6 4>,
> > +				<0 0  7 &gic 0  7 4>,
> > +				<0 0  8 &gic 0  8 4>,
> > +				<0 0  9 &gic 0  9 4>,
> > +				<0 0 10 &gic 0 10 4>,
> > +				<0 0 11 &gic 0 11 4>,
> > +				<0 0 12 &gic 0 12 4>,
> > +				<0 0 13 &gic 0 13 4>,
> > +				<0 0 14 &gic 0 14 4>,
> > +				<0 0 15 &gic 0 15 4>,
> > +				<0 0 16 &gic 0 16 4>,
> > +				<0 0 17 &gic 0 17 4>,
> > +				<0 0 18 &gic 0 18 4>,
> > +				<0 0 19 &gic 0 19 4>,
> > +				<0 0 20 &gic 0 20 4>,
> > +				<0 0 21 &gic 0 21 4>,
> > +				<0 0 22 &gic 0 22 4>,
> > +				<0 0 23 &gic 0 23 4>,
> > +				<0 0 24 &gic 0 24 4>,
> > +				<0 0 25 &gic 0 25 4>,
> > +				<0 0 26 &gic 0 26 4>,
> > +				<0 0 27 &gic 0 27 4>,
> > +				<0 0 28 &gic 0 28 4>,
> > +				<0 0 29 &gic 0 29 4>,
> > +				<0 0 30 &gic 0 30 4>,
> > +				<0 0 31 &gic 0 31 4>,
> > +				<0 0 32 &gic 0 32 4>,
> > +				<0 0 33 &gic 0 33 4>,
> > +				<0 0 34 &gic 0 34 4>,
> > +				<0 0 35 &gic 0 35 4>,
> > +				<0 0 36 &gic 0 36 4>,
> > +				<0 0 37 &gic 0 37 4>,
> > +				<0 0 38 &gic 0 38 4>,
> > +				<0 0 39 &gic 0 39 4>,
> > +				<0 0 40 &gic 0 40 4>,
> > +				<0 0 41 &gic 0 41 4>,
> > +				<0 0 42 &gic 0 42 4>;
> > +	};
> > +};
> > diff --git a/arch/arm/mach-vexpress/Makefile.boot b/arch/arm/mach-vexpress/Makefile.boot
> > index 318d308..5c633c5 100644
> > --- a/arch/arm/mach-vexpress/Makefile.boot
> > +++ b/arch/arm/mach-vexpress/Makefile.boot
> > @@ -7,4 +7,5 @@ initrd_phys-y	:= 0x60800000
> >  dtb-$(CONFIG_ARCH_VEXPRESS_DT)	+= vexpress-v2p-ca5s.dtb \
> >  				   vexpress-v2p-ca9.dtb \
> >  				   vexpress-v2p-ca15-tc1.dtb \
> > -				   vexpress-v2p-ca15_a7.dtb
> > +				   vexpress-v2p-ca15_a7.dtb \
> > +				   vexpress-xenvm-4.2.dtb
> > 
>