From 9b5da0c6238e7b7172478dc6b7481fa000ae7656 Mon Sep 17 00:00:00 2001 From: Erico Nunes Date: Mon, 21 Oct 2024 19:50:01 +0200 Subject: [PATCH] Primary node clarification for VK_EXT_physical_device_drm The extension hinted that the primary node represents display capabilities as its intended purpose, but the current text let it ambiguous enough that there has been confusion and proposed implementations which expose different devices for the primary node. Add clarification notes to further define the scope of primary node in the context of this extension. Signed-off-by: Erico Nunes --- appendices/VK_EXT_physical_device_drm.adoc | 24 +++++++++++++++------- xml/vk.xml | 2 +- 2 files changed, 18 insertions(+), 8 deletions(-) diff --git a/appendices/VK_EXT_physical_device_drm.adoc b/appendices/VK_EXT_physical_device_drm.adoc index 72bcfed20..7cb850074 100644 --- a/appendices/VK_EXT_physical_device_drm.adoc +++ b/appendices/VK_EXT_physical_device_drm.adoc @@ -7,7 +7,7 @@ include::{generated}/meta/{refprefix}VK_EXT_physical_device_drm.adoc[] === Other Extension Metadata *Last Modified Date*:: - 2021-06-09 + 2024-11-07 *IP Status*:: No known IP claims. *Contributors*:: @@ -25,16 +25,22 @@ Unlike the EGL extension, this extension does not expose a string containing the name of the device file and instead exposes device minor numbers. DRM defines multiple device node types. -Each physical device may have one primary node and one render node -associated. -Physical devices may have no primary node (e.g. if the device does not have -a display subsystem), may have no render node (e.g. if it is a software -rendering engine), or may have neither (e.g. if it is a software rendering -engine without a display subsystem). +Each physical device can only be associated with a single underlying DRM +device, which has one primary node and may have one render node. + +A physical device always has the primary node if it is associated with a DRM +device. It may have no render node if e.g. it uses a software rendering engine. To query DRM properties for a physical device, chain slink:VkPhysicalDeviceDrmPropertiesEXT to slink:VkPhysicalDeviceProperties2. +[NOTE] +==== +This extension only returns the primary node and render node from the same +DRM device for a Vulkan physical device. Implementations should not return the +primary node and render node from different DRM devices. +==== + include::{generated}/interfaces/VK_EXT_physical_device_drm.adoc[] === References @@ -44,5 +50,9 @@ include::{generated}/interfaces/VK_EXT_physical_device_drm.adoc[] === Version History + * Revision 2, 2024-11-07 + ** Clarification about the meaning of the primary node + ** Clarification to not advertise more than one DRM device + * Revision 1, 2021-06-09 ** First stable revision diff --git a/xml/vk.xml b/xml/vk.xml index 86d497ece..4d772730d 100644 --- a/xml/vk.xml +++ b/xml/vk.xml @@ -22497,7 +22497,7 @@ typedef void* MTLSharedEvent_id; - +