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| author | Cédric Le Goater <clg@kaod.org> | 2019-04-18 12:39:31 +0200 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2019-04-30 11:35:16 +0200 |
| commit | 13ce3297c5766b9541b6a7a255794c5168a7ae1a (patch) | |
| tree | e2d75ee5fedbc81061d5c359f140fb4656c8ec5c /Documentation | |
| parent | KVM: PPC: Book3S HV: XIVE: Add a control to configure a source (diff) | |
| download | linux-13ce3297c5766b9541b6a7a255794c5168a7ae1a.tar.xz linux-13ce3297c5766b9541b6a7a255794c5168a7ae1a.zip | |
KVM: PPC: Book3S HV: XIVE: Add controls for the EQ configuration
These controls will be used by the H_INT_SET_QUEUE_CONFIG and
H_INT_GET_QUEUE_CONFIG hcalls from QEMU to configure the underlying
Event Queue in the XIVE IC. They will also be used to restore the
configuration of the XIVE EQs and to capture the internal run-time
state of the EQs. Both 'get' and 'set' rely on an OPAL call to access
the EQ toggle bit and EQ index which are updated by the XIVE IC when
event notifications are enqueued in the EQ.
The value of the guest physical address of the event queue is saved in
the XIVE internal xive_q structure for later use. That is when
migration needs to mark the EQ pages dirty to capture a consistent
memory state of the VM.
To be noted that H_INT_SET_QUEUE_CONFIG does not require the extra
OPAL call setting the EQ toggle bit and EQ index to configure the EQ,
but restoring the EQ state will.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/virtual/kvm/devices/xive.txt | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/xive.txt b/Documentation/virtual/kvm/devices/xive.txt index 33c64b2cdbe8..cc13bfd5cf53 100644 --- a/Documentation/virtual/kvm/devices/xive.txt +++ b/Documentation/virtual/kvm/devices/xive.txt @@ -53,3 +53,37 @@ the legacy interrupt mode, referred as XICS (POWER7/8). -ENXIO: CPU event queues not configured or configuration of the underlying HW interrupt failed -EBUSY: No CPU available to serve interrupt + + 4. KVM_DEV_XIVE_GRP_EQ_CONFIG (read-write) + Configures an event queue of a CPU + Attributes: + EQ descriptor identifier (64-bit) + The EQ descriptor identifier is a tuple (server, priority) : + bits: | 63 .... 32 | 31 .. 3 | 2 .. 0 + values: | unused | server | priority + The kvm_device_attr.addr points to : + struct kvm_ppc_xive_eq { + __u32 flags; + __u32 qshift; + __u64 qaddr; + __u32 qtoggle; + __u32 qindex; + __u8 pad[40]; + }; + - flags: queue flags + KVM_XIVE_EQ_ALWAYS_NOTIFY (required) + forces notification without using the coalescing mechanism + provided by the XIVE END ESBs. + - qshift: queue size (power of 2) + - qaddr: real address of queue + - qtoggle: current queue toggle bit + - qindex: current queue index + - pad: reserved for future use + Errors: + -ENOENT: Invalid CPU number + -EINVAL: Invalid priority + -EINVAL: Invalid flags + -EINVAL: Invalid queue size + -EINVAL: Invalid queue address + -EFAULT: Invalid user pointer for attr->addr. + -EIO: Configuration of the underlying HW failed |