sphinx.addnodesdocument)}( rawsourcechildren]( translations LanguagesNode)}(hhh](h pending_xref)}(hhh]docutils.nodesTextChinese (Simplified)}parenthsba attributes}(ids]classes]names]dupnames]backrefs] refdomainstdreftypedoc reftarget/translations/zh_CN/gpu/vkmsmodnameN classnameN refexplicitutagnamehhh ubh)}(hhh]hChinese (Traditional)}hh2sbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget/translations/zh_TW/gpu/vkmsmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hItalian}hhFsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget/translations/it_IT/gpu/vkmsmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hJapanese}hhZsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget/translations/ja_JP/gpu/vkmsmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hKorean}hhnsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget/translations/ko_KR/gpu/vkmsmodnameN classnameN refexplicituh1hhh ubh)}(hhh]hSpanish}hhsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget/translations/sp_SP/gpu/vkmsmodnameN classnameN refexplicituh1hhh ubeh}(h]h ]h"]h$]h&]current_languageEnglishuh1h hh _documenthsourceNlineNubhtarget)}(h .. _vkms:h]h}(h]h ]h"]h$]h&]refidvkmsuh1hhKhhhhh6/var/lib/git/docbuild/linux/Documentation/gpu/vkms.rstubhsection)}(hhh](htitle)}(h#drm/vkms Virtual Kernel Modesettingh]h#drm/vkms Virtual Kernel Modesetting}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhhhhhKubh paragraph)}(hVKMS is a software-only model of a KMS driver that is useful for testing and for running X (or similar) on headless machines. VKMS aims to enable a virtual display with no need of a hardware display capability, releasing the GPU in DRM API tests.h]hVKMS is a software-only model of a KMS driver that is useful for testing and for running X (or similar) on headless machines. VKMS aims to enable a virtual display with no need of a hardware display capability, releasing the GPU in DRM API tests.}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhW/var/lib/git/docbuild/linux/Documentation/gpu/vkms:7: ./drivers/gpu/drm/vkms/vkms_drv.chKhhhhubh)}(hhh](h)}(hSetuph]hSetup}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhhhhhK ubh)}(h6The VKMS driver can be setup with the following steps:h]h6The VKMS driver can be setup with the following steps:}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK hhhhubh)}(h!To check if VKMS is loaded, run::h]h To check if VKMS is loaded, run:}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubh literal_block)}(hlsmod | grep vkmsh]hlsmod | grep vkms}hjsbah}(h]h ]h"]h$]h&] xml:spacepreserveuh1jhhhKhhhhubh)}(hThis should list the VKMS driver. If no output is obtained, then you need to enable and/or load the VKMS driver. Ensure that the VKMS driver has been set as a loadable module in your kernel config file. Do::h]hThis should list the VKMS driver. If no output is obtained, then you need to enable and/or load the VKMS driver. Ensure that the VKMS driver has been set as a loadable module in your kernel config file. Do:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubj)}(h[make nconfig Go to `Device Drivers> Graphics support` Enable `Virtual KMS (EXPERIMENTAL)`h]h[make nconfig Go to `Device Drivers> Graphics support` Enable `Virtual KMS (EXPERIMENTAL)`}hj#sbah}(h]h ]h"]h$]h&]jjuh1jhhhKhhhhubh)}(h]Compile and build the kernel for the changes to get reflected. Now, to load the driver, use::h]h\Compile and build the kernel for the changes to get reflected. Now, to load the driver, use:}(hj1hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubj)}(hsudo modprobe vkmsh]hsudo modprobe vkms}hj?sbah}(h]h ]h"]h$]h&]jjuh1jhhhK!hhhhubh)}(hOn running the lsmod command now, the VKMS driver will appear listed. You can also observe the driver being loaded in the dmesg logs.h]hOn running the lsmod command now, the VKMS driver will appear listed. You can also observe the driver being loaded in the dmesg logs.}(hjMhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK#hhhhubh)}(hThe VKMS driver has optional features to simulate different kinds of hardware, which are exposed as module options. You can use the `modinfo` command to see the module options for vkms::h](hThe VKMS driver has optional features to simulate different kinds of hardware, which are exposed as module options. You can use the }(hj[hhhNhNubhtitle_reference)}(h `modinfo`h]hmodinfo}(hjehhhNhNubah}(h]h ]h"]h$]h&]uh1jchj[ubh, command to see the module options for vkms:}(hj[hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK&hhhhubj)}(h modinfo vkmsh]h modinfo vkms}hj}sbah}(h]h ]h"]h$]h&]jjuh1jhhhK*hhhhubh)}(hModule options are helpful when testing, and enabling modules can be done while loading vkms. For example, to load vkms with cursor enabled, use::h]hModule options are helpful when testing, and enabling modules can be done while loading vkms. For example, to load vkms with cursor enabled, use:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK,hhhhubj)}(h"sudo modprobe vkms enable_cursor=1h]h"sudo modprobe vkms enable_cursor=1}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhK0hhhhubh)}(hTo disable the driver, use ::h]hTo disable the driver, use}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK2hhhhubj)}(hsudo modprobe -r vkmsh]hsudo modprobe -r vkms}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhK4hhhhubeh}(h]setupah ]h"]setupah$]h&]uh1hhhhhhhhK ubh)}(hhh](h)}(hConfiguring With Configfsh]hConfiguring With Configfs}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhK7ubh)}(hLIt is possible to create and configure multiple VKMS instances via configfs.h]hLIt is possible to create and configure multiple VKMS instances via configfs.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK9hjhhubh)}(h-Start by mounting configfs and loading VKMS::h]h,Start by mounting configfs and loading VKMS:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK;hjhhubj)}(h6sudo mount -t configfs none /config sudo modprobe vkmsh]h6sudo mount -t configfs none /config sudo modprobe vkms}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhK=hjhhubh)}(hOnce VKMS is loaded, ``/config/vkms`` is created automatically. Each directory under ``/config/vkms`` represents a VKMS instance, create a new one::h](hOnce VKMS is loaded, }(hjhhhNhNubhliteral)}(h``/config/vkms``h]h /config/vkms}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1jhjubh0 is created automatically. Each directory under }(hjhhhNhNubj)}(h``/config/vkms``h]h /config/vkms}(hj"hhhNhNubah}(h]h ]h"]h$]h&]uh1jhjubh. represents a VKMS instance, create a new one:}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK@hjhhubj)}(hsudo mkdir /config/vkms/my-vkmsh]hsudo mkdir /config/vkms/my-vkms}hj:sbah}(h]h ]h"]h$]h&]jjuh1jhhhKChjhhubh)}(h&By default, the instance is disabled::h]h%By default, the instance is disabled:}(hjHhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKEhjhhubj)}(h"cat /config/vkms/my-vkms/enabled 0h]h"cat /config/vkms/my-vkms/enabled 0}hjVsbah}(h]h ]h"]h$]h&]jjuh1jhhhKGhjhhubh)}(hPAnd directories are created for each configurable item of the display pipeline::h]hOAnd directories are created for each configurable item of the display pipeline:}(hjdhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKJhjhhubj)}(httree /config/vkms/my-vkms ├── connectors ├── crtcs ├── enabled ├── encoders └── planesh]httree /config/vkms/my-vkms ├── connectors ├── crtcs ├── enabled ├── encoders └── planes}hjrsbah}(h]h ]h"]h$]h&]jjuh1jhhhKLhjhhubh)}(h_To add items to the display pipeline, create one or more directories under the available paths.h]h_To add items to the display pipeline, create one or more directories under the available paths.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKShjhhubh)}(h&Start by creating one or more planes::h]h%Start by creating one or more planes:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKVhjhhubj)}(h-sudo mkdir /config/vkms/my-vkms/planes/plane0h]h-sudo mkdir /config/vkms/my-vkms/planes/plane0}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKXhjhhubh)}(h%Planes have 1 configurable attribute:h]h%Planes have 1 configurable attribute:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKZhjhhubh bullet_list)}(hhh]h list_item)}(hrtype: Plane type: 0 overlay, 1 primary, 2 cursor (same values as those exposed by the "type" property of a plane) h]h)}(hqtype: Plane type: 0 overlay, 1 primary, 2 cursor (same values as those exposed by the "type" property of a plane)h]hutype: Plane type: 0 overlay, 1 primary, 2 cursor (same values as those exposed by the “type” property of a plane)}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK\hjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubah}(h]h ]h"]h$]h&]bullet-uh1jhhhK\hjhhubh)}(h(Continue by creating one or more CRTCs::h]h'Continue by creating one or more CRTCs:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK_hjhhubj)}(h+sudo mkdir /config/vkms/my-vkms/crtcs/crtc0h]h+sudo mkdir /config/vkms/my-vkms/crtcs/crtc0}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKahjhhubh)}(h$CRTCs have 1 configurable attribute:h]h$CRTCs have 1 configurable attribute:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKchjhhubj)}(hhh]j)}(hKwriteback: Enable or disable writeback connector support by writing 1 or 0 h]h)}(hJwriteback: Enable or disable writeback connector support by writing 1 or 0h]hJwriteback: Enable or disable writeback connector support by writing 1 or 0}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKehj ubah}(h]h ]h"]h$]h&]uh1jhj hhhhhNubah}(h]h ]h"]h$]h&]jjuh1jhhhKehjhhubh)}(h#Next, create one or more encoders::h]h"Next, create one or more encoders:}(hj*hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKghjhhubj)}(h1sudo mkdir /config/vkms/my-vkms/encoders/encoder0h]h1sudo mkdir /config/vkms/my-vkms/encoders/encoder0}hj8sbah}(h]h ]h"]h$]h&]jjuh1jhhhKihjhhubh)}(h3Last but not least, create one or more connectors::h]h2Last but not least, create one or more connectors:}(hjFhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKkhjhhubj)}(h5sudo mkdir /config/vkms/my-vkms/connectors/connector0h]h5sudo mkdir /config/vkms/my-vkms/connectors/connector0}hjTsbah}(h]h ]h"]h$]h&]jjuh1jhhhKmhjhhubh)}(h)Connectors have 1 configurable attribute:h]h)Connectors have 1 configurable attribute:}(hjbhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKohjhhubj)}(hhh]j)}(hstatus: Connection status: 1 connected, 2 disconnected, 3 unknown (same values as those exposed by the "status" property of a connector) h]h)}(hstatus: Connection status: 1 connected, 2 disconnected, 3 unknown (same values as those exposed by the "status" property of a connector)h]hstatus: Connection status: 1 connected, 2 disconnected, 3 unknown (same values as those exposed by the “status” property of a connector)}(hjwhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKqhjsubah}(h]h ]h"]h$]h&]uh1jhjphhhhhNubah}(h]h ]h"]h$]h&]jjuh1jhhhKqhjhhubh)}(h@To finish the configuration, link the different pipeline items::h]h?To finish the configuration, link the different pipeline items:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKthjhhubj)}(hX.sudo ln -s /config/vkms/my-vkms/crtcs/crtc0 /config/vkms/my-vkms/planes/plane0/possible_crtcs sudo ln -s /config/vkms/my-vkms/crtcs/crtc0 /config/vkms/my-vkms/encoders/encoder0/possible_crtcs sudo ln -s /config/vkms/my-vkms/encoders/encoder0 /config/vkms/my-vkms/connectors/connector0/possible_encodersh]hX.sudo ln -s /config/vkms/my-vkms/crtcs/crtc0 /config/vkms/my-vkms/planes/plane0/possible_crtcs sudo ln -s /config/vkms/my-vkms/crtcs/crtc0 /config/vkms/my-vkms/encoders/encoder0/possible_crtcs sudo ln -s /config/vkms/my-vkms/encoders/encoder0 /config/vkms/my-vkms/connectors/connector0/possible_encoders}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKvhjhhubh)}(hOSince at least one primary plane is required, make sure to set the right type::h]hNSince at least one primary plane is required, make sure to set the right type:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKzhjhhubj)}(h;echo "1" | sudo tee /config/vkms/my-vkms/planes/plane0/typeh]h;echo "1" | sudo tee /config/vkms/my-vkms/planes/plane0/type}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhK|hjhhubh)}(h`_ .h](hThe IGT GPU Tools is a test suite used specifically for debugging and development of the DRM drivers. The IGT Tools can be installed from }(hj6hhhNhNubh reference)}(h:`here `_h]hhere}(hj@hhhNhNubah}(h]h ]h"]h$]h&]namehererefuri0https://gitlab.freedesktop.org/drm/igt-gpu-toolsuh1j>hj6ubh)}(h3 h]h}(h]hereah ]h"]hereah$]h&]refurijQuh1h referencedKhj6ubh .}(hj6hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhj%hhubh)}(hlThe tests need to be run without a compositor, so you need to switch to text only mode. You can do this by::h]hkThe tests need to be run without a compositor, so you need to switch to text only mode. You can do this by:}(hjjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj%hhubj)}(h(sudo systemctl isolate multi-user.targeth]h(sudo systemctl isolate multi-user.target}hjxsbah}(h]h ]h"]h$]h&]jjuh1jhhhKhj%hhubh)}(h!To return to graphical mode, do::h]h To return to graphical mode, do:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj%hhubj)}(h'sudo systemctl isolate graphical.targeth]h'sudo systemctl isolate graphical.target}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKhj%hhubh)}(hOnce you are in text only mode, you can run tests using the IGT_FORCE_DRIVER variable to specify the device filter for the driver we want to test. IGT_FORCE_DRIVER can also be used with the run-tests.sh script to run the tests for a specific driver::h]hOnce you are in text only mode, you can run tests using the IGT_FORCE_DRIVER variable to specify the device filter for the driver we want to test. IGT_FORCE_DRIVER can also be used with the run-tests.sh script to run the tests for a specific driver:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj%hhubj)}(hsudo IGT_FORCE_DRIVER="vkms" ./build/tests/ sudo IGT_FORCE_DRIVER="vkms" ./scripts/run-tests.sh -t h]hsudo IGT_FORCE_DRIVER="vkms" ./build/tests/ sudo IGT_FORCE_DRIVER="vkms" ./scripts/run-tests.sh -t }hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKhj%hhubh)}(hdFor example, to test the functionality of the writeback library, we can run the kms_writeback test::h]hcFor example, to test the functionality of the writeback library, we can run the kms_writeback test:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj%hhubj)}(h}sudo IGT_FORCE_DRIVER="vkms" ./build/tests/kms_writeback sudo IGT_FORCE_DRIVER="vkms" ./scripts/run-tests.sh -t kms_writebackh]h}sudo IGT_FORCE_DRIVER="vkms" ./build/tests/kms_writeback sudo IGT_FORCE_DRIVER="vkms" ./scripts/run-tests.sh -t kms_writeback}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKhj%hhubh)}(hEYou can also run subtests if you do not want to run the entire test::h]hDYou can also run subtests if you do not want to run the entire test:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj%hhubj)}(hRsudo IGT_FORCE_DRIVER="vkms" ./build/tests/kms_flip --run-subtest basic-plain-fliph]hRsudo IGT_FORCE_DRIVER="vkms" ./build/tests/kms_flip --run-subtest basic-plain-flip}hjsbah}(h]h ]h"]h$]h&]jjuh1jhhhKhj%hhubeh}(h]testing-with-igtah ]h"]testing with igtah$]h&]uh1hhhhhhhhKubh)}(hhh](h)}(hTesting With KUnith]hTesting With KUnit}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(hKUnit (Kernel unit testing framework) provides a common framework for unit tests within the Linux kernel. More information in ../dev-tools/kunit/index.rst .h]hKUnit (Kernel unit testing framework) provides a common framework for unit tests within the Linux kernel. More information in ../dev-tools/kunit/index.rst .}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubh)}(hTo run the VKMS KUnit tests::h]hTo run the VKMS KUnit tests:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubj)}(hItools/testing/kunit/kunit.py run --kunitconfig=drivers/gpu/drm/vkms/testsh]hItools/testing/kunit/kunit.py run --kunitconfig=drivers/gpu/drm/vkms/tests}hj+sbah}(h]h ]h"]h$]h&]jjuh1jhhhKhjhhubeh}(h]testing-with-kunitah ]h"]testing with kunitah$]h&]uh1hhhhhhhhKubh)}(hhh](h)}(hTODOh]hTODO}(hjDhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjAhhhhhKubh)}(hbIf you want to do any of the items listed below, please share your interest with VKMS maintainers.h]hbIf you want to do any of the items listed below, please share your interest with VKMS maintainers.}(hjRhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjAhhubh)}(hhh](h)}(hIGT better supporth]hIGT better support}(hjchhhNhNubah}(h]h ]h"]h$]h&]uh1hhj`hhhhhKubh)}(h Debugging:h]h Debugging:}(hjqhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj`hhubj)}(hhh]j)}(hHkms_plane: some test cases are failing due to timeout on capturing CRC; h]h)}(hGkms_plane: some test cases are failing due to timeout on capturing CRC;h]hGkms_plane: some test cases are failing due to timeout on capturing CRC;}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubah}(h]h ]h"]h$]h&]jjuh1jhhhKhj`hhubh)}(h$Virtual hardware (vblank-less) mode:h]h$Virtual hardware (vblank-less) mode:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj`hhubj)}(hhh]j)}(hXVKMS already has support for vblanks simulated via hrtimers, which can be tested with kms_flip test; in some way, we can say that VKMS already mimics the real hardware vblank. However, we also have virtual hardware that does not support vblank interrupt and completes page_flip events right away; in this case, compositor developers may end up creating a busy loop on virtual hardware. It would be useful to support Virtual Hardware behavior in VKMS because this can help compositor developers to test their features in multiple scenarios. h]h)}(hXVKMS already has support for vblanks simulated via hrtimers, which can be tested with kms_flip test; in some way, we can say that VKMS already mimics the real hardware vblank. However, we also have virtual hardware that does not support vblank interrupt and completes page_flip events right away; in this case, compositor developers may end up creating a busy loop on virtual hardware. It would be useful to support Virtual Hardware behavior in VKMS because this can help compositor developers to test their features in multiple scenarios.h]hXVKMS already has support for vblanks simulated via hrtimers, which can be tested with kms_flip test; in some way, we can say that VKMS already mimics the real hardware vblank. However, we also have virtual hardware that does not support vblank interrupt and completes page_flip events right away; in this case, compositor developers may end up creating a busy loop on virtual hardware. It would be useful to support Virtual Hardware behavior in VKMS because this can help compositor developers to test their features in multiple scenarios.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubah}(h]h ]h"]h$]h&]jjuh1jhhhKhj`hhubeh}(h]igt-better-supportah ]h"]igt better supportah$]h&]uh1hhjAhhhhhKubh)}(hhh](h)}(hAdd Plane Featuresh]hAdd Plane Features}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(h8There's lots of plane features we could add support for:h]h:There’s lots of plane features we could add support for:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubj)}(hhh](j)}(h8Add background color KMS property[Good to get started]. h]h)}(h7Add background color KMS property[Good to get started].h]h7Add background color KMS property[Good to get started].}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubj)}(h Scaling. h]h)}(hScaling.h]hScaling.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubj)}(h`Additional buffer formats. Low/high bpp RGB formats would be interesting [Good to get started]. h]h)}(h_Additional buffer formats. Low/high bpp RGB formats would be interesting [Good to get started].h]h_Additional buffer formats. Low/high bpp RGB formats would be interesting [Good to get started].}(hj-hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhj)ubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubj)}(hUAsync updates (currently only possible on cursor plane using the legacy cursor api). h]h)}(hTAsync updates (currently only possible on cursor plane using the legacy cursor api).h]hTAsync updates (currently only possible on cursor plane using the legacy cursor api).}(hjEhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjAubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubeh}(h]h ]h"]h$]h&]jjuh1jhhhKhjhhubh)}(hFor all of these, we also want to review the igt test coverage and make sure all relevant igt testcases work on vkms. They are good options for internship project.h]hFor all of these, we also want to review the igt test coverage and make sure all relevant igt testcases work on vkms. They are good options for internship project.}(hj_hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubeh}(h]add-plane-featuresah ]h"]add plane featuresah$]h&]uh1hhjAhhhhhKubh)}(hhh](h)}(hRuntime Configurationh]hRuntime Configuration}(hjxhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjuhhhhhKubh)}(huWe want to be able to reconfigure vkms instance without having to reload the module through configfs. Use/Test-cases:h]huWe want to be able to reconfigure vkms instance without having to reload the module through configfs. Use/Test-cases:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjuhhubj)}(hhh](j)}(h]Hotplug/hotremove connectors on the fly (to be able to test DP MST handling of compositors). h]h)}(h\Hotplug/hotremove connectors on the fly (to be able to test DP MST handling of compositors).h]h\Hotplug/hotremove connectors on the fly (to be able to test DP MST handling of compositors).}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubj)}(h`Change output configuration: Plug/unplug screens, change EDID, allow changing the refresh rate. h]h)}(h_Change output configuration: Plug/unplug screens, change EDID, allow changing the refresh rate.h]h_Change output configuration: Plug/unplug screens, change EDID, allow changing the refresh rate.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubeh}(h]h ]h"]h$]h&]jjuh1jhhhKhjuhhubeh}(h]runtime-configurationah ]h"]runtime configurationah$]h&]uh1hhjAhhhhhKubh)}(hhh](h)}(hWriteback supporth]hWriteback support}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubj)}(hhh](j)}(hThe writeback and CRC capture operations share the use of composer_enabled boolean to ensure vblanks. Probably, when these operations work together, composer_enabled needs to refcounting the composer state to proper work. [Good to get started] h]h)}(hThe writeback and CRC capture operations share the use of composer_enabled boolean to ensure vblanks. Probably, when these operations work together, composer_enabled needs to refcounting the composer state to proper work. [Good to get started]h]hThe writeback and CRC capture operations share the use of composer_enabled boolean to ensure vblanks. Probably, when these operations work together, composer_enabled needs to refcounting the composer state to proper work. [Good to get started]}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubj)}(hpAdd support for cloned writeback outputs and related test cases using a cloned output in the IGT kms_writeback. h]h)}(hoAdd support for cloned writeback outputs and related test cases using a cloned output in the IGT kms_writeback.h]hoAdd support for cloned writeback outputs and related test cases using a cloned output in the IGT kms_writeback.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubj)}(hAs a v4l device. This is useful for debugging compositors on special vkms configurations, so that developers see what's really going on. h]h)}(hAs a v4l device. This is useful for debugging compositors on special vkms configurations, so that developers see what's really going on.h]hAs a v4l device. This is useful for debugging compositors on special vkms configurations, so that developers see what’s really going on.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhMhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubeh}(h]h ]h"]h$]h&]jjuh1jhhhKhjhhubeh}(h]writeback-supportah ]h"]writeback supportah$]h&]uh1hhjAhhhhhKubh)}(hhh](h)}(hOutput Featuresh]hOutput Features}(hjBhhhNhNubah}(h]h ]h"]h$]h&]uh1hhj?hhhhhMubj)}(hhh](j)}(hVariable refresh rate/freesync support. This probably needs prime buffer sharing support, so that we can use vgem fences to simulate rendering in testing. Also needs support to specify the EDID. h]h)}(hVariable refresh rate/freesync support. This probably needs prime buffer sharing support, so that we can use vgem fences to simulate rendering in testing. Also needs support to specify the EDID.h]hVariable refresh rate/freesync support. This probably needs prime buffer sharing support, so that we can use vgem fences to simulate rendering in testing. Also needs support to specify the EDID.}(hjWhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhMhjSubah}(h]h ]h"]h$]h&]uh1jhjPhhhhhNubj)}(h~Add support for link status, so that compositors can validate their runtime fallbacks when e.g. a Display Port link goes bad. h]h)}(h}Add support for link status, so that compositors can validate their runtime fallbacks when e.g. a Display Port link goes bad.h]h}Add support for link status, so that compositors can validate their runtime fallbacks when e.g. a Display Port link goes bad.}(hjohhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhM hjkubah}(h]h ]h"]h$]h&]uh1jhjPhhhhhNubeh}(h]h ]h"]h$]h&]jjuh1jhhhMhj?hhubeh}(h]output-featuresah ]h"]output featuresah$]h&]uh1hhjAhhhhhMubh)}(hhh](h)}(hCRC API Improvementsh]hCRC API Improvements}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhMubj)}(hhh]j)}(hJOptimize CRC computation ``compute_crc()`` and plane blending ``blend()`` h]h)}(hIOptimize CRC computation ``compute_crc()`` and plane blending ``blend()``h](hOptimize CRC computation }(hjhhhNhNubj)}(h``compute_crc()``h]h compute_crc()}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1jhjubh and plane blending }(hjhhhNhNubj)}(h ``blend()``h]hblend()}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1jhjubeh}(h]h ]h"]h$]h&]uh1hhhhMhjubah}(h]h ]h"]h$]h&]uh1jhjhhhhhNubah}(h]h ]h"]h$]h&]jjuh1jhhhMhjhhubeh}(h]crc-api-improvementsah ]h"]crc api improvementsah$]h&]uh1hhjAhhhhhMubh)}(hhh](h)}(hAtomic Check using eBPFh]hAtomic Check using eBPF}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhMubh)}(hXAtomic drivers have lots of restrictions which are not exposed to userspace in any explicit form through e.g. possible property values. Userspace can only inquiry about these limits through the atomic IOCTL, possibly using the TEST_ONLY flag. Trying to add configurable code for all these limits, to allow compositors to be tested against them, would be rather futile exercise. Instead we could add support for eBPF to validate any kind of atomic state, and implement a library of different restrictions.h]hXAtomic drivers have lots of restrictions which are not exposed to userspace in any explicit form through e.g. possible property values. Userspace can only inquiry about these limits through the atomic IOCTL, possibly using the TEST_ONLY flag. Trying to add configurable code for all these limits, to allow compositors to be tested against them, would be rather futile exercise. Instead we could add support for eBPF to validate any kind of atomic state, and implement a library of different restrictions.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhMhjhhubh)}(hhThis needs a bunch of features (plane compositing, multiple outputs, ...) enabled already to make sense.h]hhThis needs a bunch of features (plane compositing, multiple outputs, ...) enabled already to make sense.}(hj hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhMhjhhubeh}(h]atomic-check-using-ebpfah ]h"]atomic check using ebpfah$]h&]uh1hhjAhhhhhMubeh}(h]todoah ]h"]todoah$]h&]uh1hhhhhhhhKubeh}(h](#drm-vkms-virtual-kernel-modesettingheh ]h"](#drm/vkms virtual kernel modesettingvkmseh$]h&]uh1hhhhhhhhKexpect_referenced_by_name}j.hsexpect_referenced_by_id}hhsubeh}(h]h ]h"]h$]h&]sourcehuh1hcurrent_sourceN current_lineNsettingsdocutils.frontendValues)}(hN generatorN datestampN source_linkN source_urlN toc_backlinksentryfootnote_backlinksK sectnum_xformKstrip_commentsNstrip_elements_with_classesN strip_classesN report_levelK halt_levelKexit_status_levelKdebugNwarning_streamN tracebackinput_encoding utf-8-siginput_encoding_error_handlerstrictoutput_encodingutf-8output_encoding_error_handlerjXerror_encodingutf-8error_encoding_error_handlerbackslashreplace language_codeenrecord_dependenciesNconfigN id_prefixhauto_id_prefixid dump_settingsNdump_internalsNdump_transformsNdump_pseudo_xmlNexpose_internalsNstrict_visitorN_disable_configN_sourceh _destinationN _config_files]7/var/lib/git/docbuild/linux/Documentation/docutils.confafile_insertion_enabled raw_enabledKline_length_limitM'pep_referencesN pep_base_urlhttps://peps.python.org/pep_file_url_templatepep-%04drfc_referencesN rfc_base_url&https://datatracker.ietf.org/doc/html/ tab_widthKtrim_footnote_reference_spacesyntax_highlightlong smart_quotessmartquotes_locales]character_level_inline_markupdoctitle_xform docinfo_xformKsectsubtitle_xform image_loadinglinkembed_stylesheetcloak_email_addressessection_self_linkenvNubreporterNindirect_targets]substitution_defs}substitution_names}refnames}refids}h]hasnameids}(j.hj-j*jjj"jjjj[jXj>j;j%j"jjjrjojjj<j9jjjjjju nametypes}(j.j-jj"jj[j>j%jjrjj<jjjuh}(hhj*hjhjjjj%jXjRj;jj"jAjj`jojjjuj9jjj?jjjju footnote_refs} citation_refs} autofootnotes]autofootnote_refs]symbol_footnotes]symbol_footnote_refs] footnotes] citations]autofootnote_startKsymbol_footnote_startK id_counter collectionsCounter}Rparse_messages]transform_messages]hsystem_message)}(hhh]h)}(hhh]h*Hyperlink target "vkms" is not referenced.}hjsbah}(h]h ]h"]h$]h&]uh1hhjubah}(h]h ]h"]h$]h&]levelKtypeINFOsourcehlineKuh1juba transformerN include_log] decorationNhhub.