Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cb9d0434 authored by Christoffer Dall's avatar Christoffer Dall
Browse files

KVM: arm/arm64: Clarification and relaxation to ITS save/restore ABI 



Clarify what is meant by the save/restore ABI only supporting virtual
physical interrupts.

Relax the requirement of the order that the collection entries are
written in and be clear that there is no particular ordering enforced.

Some cosmetic changes in the capitalization of ID names to align with
the GICv3 manual and remove the empty line in the bottom of the patch.

Signed-off-by: default avatarChristoffer Dall <cdall@linaro.org>
Reviewed-by: default avatarEric Auger <eric.auger@redhat.com>
parent 28077125

Documentation/virtual/kvm/devices/arm-vgic-its.txt

+12 −11
Original line number Diff line number Diff line
@@ -97,8 +97,8 @@ Groups: 
The following ordering must be followed when restoring the GIC and the ITS:

a) restore all guest memory and create vcpus

b) restore all redistributors

c) initialize the ITS and then provide its base address

   (KVM_DEV_ARM_VGIC_CTRL_INIT, KVM_DEV_ARM_VGIC_GRP_ADDR)

c) provide the its base address

   (KVM_DEV_ARM_VGIC_GRP_ADDR)

d) restore the ITS in the following order:

   1. Restore GITS_CBASER

   2. Restore all other GITS_ registers, except GITS_CTLR!
@@ -110,12 +110,14 @@ Then vcpus can be started. 
 ITS Table ABI REV0:

 -------------------



 Revision 0 of the ABI only supports physical LPIs.

 Revision 0 of the ABI only supports the features of a virtual GICv3, and does

 not support a virtual GICv4 with support for direct injection of virtual

 interrupts for nested hypervisors.



 The device table and ITT are indexed by the deviceid and eventid,

 respectively. The collection table is not indexed by collectionid:

 CTEs are written in the table in the order of collection creation. All

 entries are 8 bytes.

 The device table and ITT are indexed by the DeviceID and EventID,

 respectively. The collection table is not indexed by CollectionID, and the

 entries in the collection are listed in no particular order.

 All entries are 8 bytes.



 Device Table Entry (DTE):
@@ -126,10 +128,10 @@ Then vcpus can be started. 
 - V indicates whether the entry is valid. If not, other fields

   are not meaningful.

 - next: equals to 0 if this entry is the last one; otherwise it

   corresponds to the deviceid offset to the next DTE, capped by

   corresponds to the DeviceID offset to the next DTE, capped by

   2^14 -1.

 - ITT_addr matches bits [51:8] of the ITT address (256 Byte aligned).

 - Size specifies the supported number of bits for the eventid,

 - Size specifies the supported number of bits for the EventID,

   minus one



 Collection Table Entry (CTE):
@@ -151,8 +153,7 @@ Then vcpus can be started. 


 where:

 - next: equals to 0 if this entry is the last one; otherwise it corresponds

   to the eventid offset to the next ITE capped by 2^16 -1.

   to the EventID offset to the next ITE capped by 2^16 -1.

 - pINTID is the physical LPI ID; if zero, it means the entry is not valid

   and other fields are not meaningful.

 - ICID is the collection ID