github/acrn-hypervisor
1
0
Fork 0
mirror of https://github.com/projectacrn/acrn-hypervisor.git synced 2025-06-22 05:30:24 +00:00
Code Issues Projects Releases Wiki Activity

doc: remove invalid kernel parameters for gvt-g

Browse Source 
After change to IDV display solution for gvt-g, the kernel parameters:
i915.domain_plane_owners, i915.domain_plane_owners and i915.enable_pvmmio
related instruction is invalid and should be removed.

Signed-off-by: Xiaoguang Wu <xiaoguang.wu@intel.com>
This commit is contained in:
Xiaoguang Wu 2020-08-06 14:25:30 +08:00 committed by David Kinder
parent f788d2746f
commit 116c7f7823
1 changed files with 0 additions and 173 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

173
doc/user-guides/kernel-parameters.rst
View File

@ -342,14 +342,6 @@ section below has more details on a few select parameters.
i915.enable_gvt=1
* - i915.enable_pvmmio
- Service VM, User VM
- Control Para-Virtualized MMIO (PVMMIO). It batches sequential MMIO writes
into a shared buffer between the Service VM and User VM
- ::
i915.enable_pvmmio=0x1F
* - i915.gvt_workload_priority
- Service VM
- Define the priority level of User VM graphics workloads
@ -373,20 +365,6 @@ section below has more details on a few select parameters.
i915.nuclear_pageflip=1
* - i915.avail_planes_per_pipe
- Service VM
- See :ref:`i915-avail-planes-owners`.
- ::
i915.avail_planes_per_pipe=0x01010F
* - i915.domain_plane_owners
- Service VM
- See :ref:`i915-avail-planes-owners`.
- ::
i915.domain_plane_owners=0x011111110000
* - i915.domain_scaler_owner
- Service VM
- See `i915.domain_scaler_owner`_
@ -401,13 +379,6 @@ section below has more details on a few select parameters.
i915.enable_guc=0x02
* - i915.avail_planes_per_pipe
- User VM
- See :ref:`i915-avail-planes-owners`.
- ::
i915.avail_planes_per_pipe=0x070F00
* - i915.enable_guc
- User VM
- Disable GuC
@ -445,38 +416,6 @@ support in the host. By default, it's not enabled, so we need to add
``i915.enable_gvt=1`` in the Service VM kernel command line. This is a Service
OS only parameter, and cannot be enabled in the User VM.
i915.enable_pvmmio
------------------
We introduce the feature named **Para-Virtualized MMIO** (PVMMIO)
to improve graphics performance of the GVT-g guest.
This feature batches sequential MMIO writes into a
shared buffer between the Service VM and User VM, and then submits a
para-virtualized command to notify to GVT-g in Service VM. This
effectively reduces the trap numbers of MMIO operations and improves
overall graphics performance.
The ``i915.enable_pvmmio`` option controls
the optimization levels of the PVMMIO feature: each bit represents a
sub-feature of the optimization. By default, all
sub-features of PVMMIO are enabled. They can also be selectively
enabled or disabled..
The PVMMIO optimization levels are:
* PVMMIO_ELSP_SUBMIT = 0x1 - Batch submission of the guest graphics
workloads
* PVMMIO_PLANE_UPDATE = 0x2 - Batch plane register update operations
* PVMMIO_PLANE_WM_UPDATE = 0x4 - Batch watermark registers update operations
* PVMMIO_MASTER_IRQ = 0x8 - Batch IRQ related registers
* PVMMIO_PPGTT_UPDATE = 0x10 - Use PVMMIO method to update the PPGTT table
of guest.
.. note:: This parameter works in both the Service VM and User VM, but
changes to one will affect the other. For example, if either Service VM or User VM
disables the PVMMIO_PPGTT_UPDATE feature, this optimization will be
disabled for both.
i915.gvt_workload_priority
--------------------------
@ -522,118 +461,6 @@ In the current configuration, we will set
This parameter is not used on UEFI platforms.
.. _i915-avail-planes-owners:
i915.avail_planes_per_pipe and i915.domain_plane_owners
-------------------------------------------------------
Both Service VM and User VM are provided a set of HW planes where they
can display their contents. Since each domain provides its content,
there is no need for any extra composition to be done through Service VM.
``i915.avail_planes_per_pipe`` and ``i915.domain_plane_owners`` work
together to provide the plane restriction (or plan-based domain
ownership) feature.
* i915.domain_plane_owners
On Intel's display hardware, each pipeline contains several planes, which are
blended
together by their Z-order and rendered to the display monitors. In
AcrnGT, we can control each planes' ownership so that the domains can
display contents on the planes they own.
The ``i915.domain_plane_owners`` parameter controls the ownership of all
the planes in the system, as shown in :numref:`i915-planes-pipes`. Each
4-bit nibble identifies the domain id owner for that plane and a group
of 4 nibbles represents a pipe. This is a Service VM only configuration
and cannot be modified at runtime. Domain ID 0x0 is for the Service VM,
the User VM use domain IDs from 0x1 to 0xF.
.. figure:: images/i915-image1.png
:width: 900px
:align: center
:name: i915-planes-pipes
i915.domain_plane_owners
For example, if we set ``i915.domain_plane_owners=0x010001101110``, the
plane ownership will be as shown in :numref:`i915-planes-example1` - Service VM
(green) owns plane 1A, 1B, 4B, 1C, and 2C, and User VM #1 owns plane 2A, 3A,
4A, 2B, 3B and 3C.
.. figure:: images/i915-image2.png
:width: 900px
:align: center
:name: i915-planes-example1
i915.domain_plane_owners example
Some other examples:
* i915.domain_plane_owners=0x022211110000 - Service VM (0x0) owns planes on pipe A;
User VM #1 (0x1) owns all planes on pipe B; and User VM #2 (0x2) owns all
planes on pipe C (since, in the representation in
:numref:`i915-planes-pipes` above, there are only 3 planes attached to
pipe C).
* i915.domain_plane_owners=0x000001110000 - Service VM owns all planes on pipe A
and pipe C; User VM #1 owns plane 1, 2 and 3 on pipe B. Plane 4 on pipe B
is owned by the Service VM so that if it wants to display notice message, it
can display on top of the User VM.
* i915.avail_planes_per_pipe
Option ``i915.avail_planes_per_pipe`` is a bitmask (shown in
:numref:`i915-avail-planes`) that tells the i915
driver which planes are available and can be exposed to the compositor.
This is a parameter that must to be set in each domain. If
``i915.avail_planes_per_pipe=0``, the plane restriction feature is disabled.
.. figure:: images/i915-image3.png
:width: 600px
:align: center
:name: i915-avail-planes
i915.avail_planes_per_pipe
For example, if we set ``i915.avail_planes_per_pipe=0x030901`` in Service VM
and ``i915.avail_planes_per_pipe=0x04060E`` in User VM, the planes will be as
shown in :numref:`i915-avail-planes-example1` and
:numref:`i915-avail-planes-example1`:
.. figure:: images/i915-image4.png
:width: 500px
:align: center
:name: i915-avail-planes-example1
Service VM i915.avail_planes_per_pipe
.. figure:: images/i915-image5.png
:width: 500px
:align: center
:name: i915-avail-planes-example2
User VM i915.avail_planes_per_pipe
``i915.avail_planes_per_pipe`` controls the view of planes from i915 drivers
inside of every domain, and ``i915.domain_plane_owners`` is the global
arbiter controlling which domain can present its content onto the
real hardware. Generally, they are aligned. For example, we can set
``i915.domain_plane_owners= 0x011111110000``,
``i915.avail_planes_per_pipe=0x00000F`` in Service VM, and
``i915.avail_planes_per_pipe=0x070F00`` in domain 1, so every domain will
only flip on the planes they owns.
However, we don't force alignment: ``avail_planes_per_pipe`` might
not be aligned with the
setting of ``domain_plane_owners``. Consider this example:
``i915.domain_plane_owners=0x011111110000``,
``i915.avail_planes_per_pipe=0x01010F`` in Service VM and
``i915.avail_planes_per_pipe=0x070F00`` in domain 1.
With this configuration, Service VM will be able to render on plane 1B and
plane 1C, however, the content of plane 1B and plane 1C will not be
flipped onto the real hardware.
i915.domain_scaler_owner
========================