docs: kvm: convert devices/vcpu.txt to ReST

- Use title markups;
- adjust indentation and add blank lines as needed;
- adjust tables to match ReST accepted formats;
- use :field: markups;
- mark code blocks as such.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 114 insertions, 0 deletions

diff --git a/Documentation/virt/kvm/devices/vcpu.rst b/Documentation/virt/kvm/devices/vcpu.rst
new file mode 100644
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+++ b/Documentation/virt/kvm/devices/vcpu.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+======================
+Generic vcpu interface
+======================
+
+The virtual cpu "device" also accepts the ioctls KVM_SET_DEVICE_ATTR,
+KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same struct
+kvm_device_attr as other devices, but targets VCPU-wide settings and controls.
+
+The groups and attributes per virtual cpu, if any, are architecture specific.
+
+1. GROUP: KVM_ARM_VCPU_PMU_V3_CTRL
+==================================
+
+:Architectures: ARM64
+
+1.1. ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_IRQ
+---------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address for PMU overflow interrupt is a
+	     pointer to an int
+
+Returns:
+
+	 =======  ========================================================
+	 -EBUSY   The PMU overflow interrupt is already set
+	 -ENXIO   The overflow interrupt not set when attempting to get it
+	 -ENODEV  PMUv3 not supported
+	 -EINVAL  Invalid PMU overflow interrupt number supplied or
+		  trying to set the IRQ number without using an in-kernel
+		  irqchip.
+	 =======  ========================================================
+
+A value describing the PMUv3 (Performance Monitor Unit v3) overflow interrupt
+number for this vcpu. This interrupt could be a PPI or SPI, but the interrupt
+type must be same for each vcpu. As a PPI, the interrupt number is the same for
+all vcpus, while as an SPI it must be a separate number per vcpu.
+
+1.2 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_INIT
+---------------------------------------
+
+:Parameters: no additional parameter in kvm_device_attr.addr
+
+Returns:
+
+	 =======  ======================================================
+	 -ENODEV  PMUv3 not supported or GIC not initialized
+	 -ENXIO   PMUv3 not properly configured or in-kernel irqchip not
+		  configured as required prior to calling this attribute
+	 -EBUSY   PMUv3 already initialized
+	 =======  ======================================================
+
+Request the initialization of the PMUv3.  If using the PMUv3 with an in-kernel
+virtual GIC implementation, this must be done after initializing the in-kernel
+irqchip.
+
+
+2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
+=================================
+
+:Architectures: ARM, ARM64
+
+2.1. ATTRIBUTES: KVM_ARM_VCPU_TIMER_IRQ_VTIMER, KVM_ARM_VCPU_TIMER_IRQ_PTIMER
+-----------------------------------------------------------------------------
+
+:Parameters: in kvm_device_attr.addr the address for the timer interrupt is a
+	     pointer to an int
+
+Returns:
+
+	 =======  =================================
+	 -EINVAL  Invalid timer interrupt number
+	 -EBUSY   One or more VCPUs has already run
+	 =======  =================================
+
+A value describing the architected timer interrupt number when connected to an
+in-kernel virtual GIC.  These must be a PPI (16 <= intid < 32).  Setting the
+attribute overrides the default values (see below).
+
+=============================  ==========================================
+KVM_ARM_VCPU_TIMER_IRQ_VTIMER  The EL1 virtual timer intid (default: 27)
+KVM_ARM_VCPU_TIMER_IRQ_PTIMER  The EL1 physical timer intid (default: 30)
+=============================  ==========================================
+
+Setting the same PPI for different timers will prevent the VCPUs from running.
+Setting the interrupt number on a VCPU configures all VCPUs created at that
+time to use the number provided for a given timer, overwriting any previously
+configured values on other VCPUs.  Userspace should configure the interrupt
+numbers on at least one VCPU after creating all VCPUs and before running any
+VCPUs.
+
+3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
+==================================
+
+:Architectures: ARM64
+
+3.1 ATTRIBUTE: KVM_ARM_VCPU_PVTIME_IPA
+--------------------------------------
+
+:Parameters: 64-bit base address
+
+Returns:
+
+	 =======  ======================================
+	 -ENXIO   Stolen time not implemented
+	 -EEXIST  Base address already set for this VCPU
+	 -EINVAL  Base address not 64 byte aligned
+	 =======  ======================================
+
+Specifies the base address of the stolen time structure for this VCPU. The
+base address must be 64 byte aligned and exist within a valid guest memory
+region. See Documentation/virt/kvm/arm/pvtime.txt for more information
+including the layout of the stolen time structure.