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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/virtual/kvm/devices/arm-vgic.txt
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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+ARM Virtual Generic Interrupt Controller (VGIC)
+===============================================
+
+Device types supported:
+ KVM_DEV_TYPE_ARM_VGIC_V2 ARM Generic Interrupt Controller v2.0
+ KVM_DEV_TYPE_ARM_VGIC_V3 ARM Generic Interrupt Controller v3.0
+
+Only one VGIC instance may be instantiated through either this API or the
+legacy KVM_CREATE_IRQCHIP api. The created VGIC will act as the VM interrupt
+controller, requiring emulated user-space devices to inject interrupts to the
+VGIC instead of directly to CPUs.
+
+Creating a guest GICv3 device requires a host GICv3 as well.
+GICv3 implementations with hardware compatibility support allow a guest GICv2
+as well.
+
+Groups:
+ KVM_DEV_ARM_VGIC_GRP_ADDR
+ Attributes:
+ KVM_VGIC_V2_ADDR_TYPE_DIST (rw, 64-bit)
+ Base address in the guest physical address space of the GIC distributor
+ register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
+ This address needs to be 4K aligned and the region covers 4 KByte.
+
+ KVM_VGIC_V2_ADDR_TYPE_CPU (rw, 64-bit)
+ Base address in the guest physical address space of the GIC virtual cpu
+ interface register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V2.
+ This address needs to be 4K aligned and the region covers 4 KByte.
+
+ KVM_VGIC_V3_ADDR_TYPE_DIST (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3 distributor
+ register mappings. Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+ This address needs to be 64K aligned and the region covers 64 KByte.
+
+ KVM_VGIC_V3_ADDR_TYPE_REDIST (rw, 64-bit)
+ Base address in the guest physical address space of the GICv3
+ redistributor register mappings. There are two 64K pages for each
+ VCPU and all of the redistributor pages are contiguous.
+ Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+ This address needs to be 64K aligned.
+
+
+ KVM_DEV_ARM_VGIC_GRP_DIST_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes two values:
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | cpu id | offset |
+
+ All distributor regs are (rw, 32-bit)
+
+ The offset is relative to the "Distributor base address" as defined in the
+ GICv2 specs. Getting or setting such a register has the same effect as
+ reading or writing the register on the actual hardware from the cpu
+ specified with cpu id field. Note that most distributor fields are not
+ banked, but return the same value regardless of the cpu id used to access
+ the register.
+ Limitations:
+ - Priorities are not implemented, and registers are RAZ/WI
+ - Currently only implemented for KVM_DEV_TYPE_ARM_VGIC_V2.
+ Errors:
+ -ENODEV: Getting or setting this register is not yet supported
+ -EBUSY: One or more VCPUs are running
+
+ KVM_DEV_ARM_VGIC_GRP_CPU_REGS
+ Attributes:
+ The attr field of kvm_device_attr encodes two values:
+ bits: | 63 .... 40 | 39 .. 32 | 31 .... 0 |
+ values: | reserved | cpu id | offset |
+
+ All CPU interface regs are (rw, 32-bit)
+
+ The offset specifies the offset from the "CPU interface base address" as
+ defined in the GICv2 specs. Getting or setting such a register has the
+ same effect as reading or writing the register on the actual hardware.
+
+ The Active Priorities Registers APRn are implementation defined, so we set a
+ fixed format for our implementation that fits with the model of a "GICv2
+ implementation without the security extensions" which we present to the
+ guest. This interface always exposes four register APR[0-3] describing the
+ maximum possible 128 preemption levels. The semantics of the register
+ indicate if any interrupts in a given preemption level are in the active
+ state by setting the corresponding bit.
+
+ Thus, preemption level X has one or more active interrupts if and only if:
+
+ APRn[X mod 32] == 0b1, where n = X / 32
+
+ Bits for undefined preemption levels are RAZ/WI.
+
+ Limitations:
+ - Priorities are not implemented, and registers are RAZ/WI
+ - Currently only implemented for KVM_DEV_TYPE_ARM_VGIC_V2.
+ Errors:
+ -ENODEV: Getting or setting this register is not yet supported
+ -EBUSY: One or more VCPUs are running
+
+ KVM_DEV_ARM_VGIC_GRP_NR_IRQS
+ Attributes:
+ A value describing the number of interrupts (SGI, PPI and SPI) for
+ this GIC instance, ranging from 64 to 1024, in increments of 32.
+
+ Errors:
+ -EINVAL: Value set is out of the expected range
+ -EBUSY: Value has already be set, or GIC has already been initialized
+ with default values.
+
+ KVM_DEV_ARM_VGIC_GRP_CTRL
+ Attributes:
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the VGIC, no additional parameter in
+ kvm_device_attr.addr.
+ Errors:
+ -ENXIO: VGIC not properly configured as required prior to calling
+ this attribute
+ -ENODEV: no online VCPU
+ -ENOMEM: memory shortage when allocating vgic internal data