{"id":6564,"date":"2024-02-29T08:57:41","date_gmt":"2024-02-29T15:57:41","guid":{"rendered":"https:\/\/jasonsblog.ddns.net\/?p=6564"},"modified":"2024-02-29T08:57:41","modified_gmt":"2024-02-29T15:57:41","slug":"hdmi-forum-rejects-open-source-hdmi-2-1-driver-support-sought-by-amd","status":"publish","type":"post","link":"https:\/\/jasonsblog.ddns.net\/index.php\/2024\/02\/29\/hdmi-forum-rejects-open-source-hdmi-2-1-driver-support-sought-by-amd\/","title":{"rendered":"HDMI Forum Rejects Open-Source HDMI 2.1 Driver Support Sought By AMD"},"content":{"rendered":"\n<p>And the megacorps were not having it, though it is worth noting how much effort AMD has been giving to support the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Open-source_software\">open-source software<\/a> community.<\/p>\n\n\n\n<p><a href=\"https:\/\/www.phoronix.com\/news\/HDMI-2.1-OSS-Rejected\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/www.phoronix.com\/news\/HDMI-2.1-OSS-Rejected<\/a><\/p>\n\n\n<div class=\"wp-block-ub-divider ub_divider ub-divider-orientation-horizontal\" id=\"ub_divider_ccaac596-3508-4ba8-93ab-d1e775e2cf95\"><div class=\"ub_divider_wrapper\" style=\"position: relative; margin-bottom: 2px; width: 100%; height: 2px; \" data-divider-alignment=\"center\"><div class=\"ub_divider_line\" style=\"border-top: 2px solid #ccc; margin-top: 2px; \"><\/div><\/div><\/div>\n\n\n<p>By Michael Larabel<\/p>\n\n\n\n<p>One of the limitations of AMD&#8217;s open-source Linux graphics driver has been the inability to implement HDMI 2.1+ functionality on the basis of legal requirements by the HDMI Forum. AMD engineers had been working to come up with a solution in conjunction with the HDMI Forum for being able to provide HDMI 2.1+ capabilities with their open-source Linux kernel driver, but it looks like those efforts for now have concluded and failed.<br><br>For three years there has been a bug report around <a href=\"https:\/\/gitlab.freedesktop.org\/drm\/amd\/-\/issues\/1417\">4K@120Hz being unavailable via HDMI 2.1<\/a> on the AMD Linux driver. Similarly, there have been bug reports like <a href=\"https:\/\/gitlab.freedesktop.org\/drm\/amd\/-\/issues\/1442\">5K @ 240Hz not possible<\/a> either with the AMD graphics driver on Linux.<br><br>As covered back in 2021, <a href=\"https:\/\/www.phoronix.com\/news\/HDMI-Closed-Spec-Hurts-Open\">the HDMI Forum closing public specification access is hurting open-source support<\/a>. AMD as well as the X.Org Foundation have been engaged with the HDMI Forum to try to come up with a solution to be able to provide open-source implementations of the now-private HDMI specs.<br><br>AMD Linux engineers have spent months working with their legal team and evaluating all HDMI features to determine if\/how they can be exposed in their open-source driver. AMD had code working internally and then the past few months were waiting on approval from the HDMI Forum&#8230; Sadly, the HDMI Forum has turned down AMD&#8217;s request for open-source driver support.<br><br>AMD Linux engineer Alex Deucher <a href=\"https:\/\/gitlab.freedesktop.org\/drm\/amd\/-\/issues\/1417#note_2303163\">commented<\/a> on the ticket:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p>&#8220;The HDMI Forum has rejected our proposal unfortunately. At this time an open source HDMI 2.1 implementation is not possible without running afoul of the HDMI Forum requirements.&#8221;<\/p>\n<\/blockquote>\n\n\n\n<p>Thus a sad day for open-source GPU drivers with no apparent solution to safely implement HDMI 2.1+ functionality within open-source display drivers&#8230;<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"https:\/\/www.phoronix.com\/image-viewer.php?id=2024&amp;image=hdmi_scheisse_lrg\" target=\"_blank\" rel=\"noreferrer noopener\"><img decoding=\"async\" src=\"https:\/\/www.phoronix.net\/image.php?id=2024&amp;image=hdmi_scheisse_med\" alt=\"Chop off HDMI\"\/><\/a><\/figure>\n\n\n\n<p>Needless to say, open-source Linux advocates should try to use DisplayPort instead if at all possible.<\/p>\n\n\n\n<p><em>Update for added context [20:30 EST]:<\/em> Further insult to the injury is also that it sounds like AMD spent months of engineering time prototyping code for showing HDMI 2.1+ features within their internal open-source AMDGPU codebase to provide for review to the HDMI Forum. If that never sees the light of day now, it&#8217;s all a largely wasted effort of significant resources.<\/p>\n\n\n\n<p>As another tid-bit, in the early days of the open-source AMD driver effort there were concerns around exposing GPU video acceleration in the open-source driver as to not potentially compromise HDCP \/ digital video restrictions with MPEG-LA and the like&#8230; It&#8217;s already been a decade since <a href=\"https:\/\/www.phoronix.com\/review\/amd_opensource_uvd\">AMD open-sourced UVD video support<\/a>. These HDMI headaches sound like much the same boat as their early days of open-source video acceleration.<\/p>\n\n\n\n<p>We&#8217;ll see if AMD can find a compromise like implementing more bits within their (closed-source) firmware or some other blob protected by their PSP IP block or the like, but in any event today&#8217;s news is very much a disappointment and means in the near-term there is unlikely to be any HDMI 2.1+ feature support in open-source drivers. So open-source supporters should be pursuing DisplayPort if at all possible for the best experience.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>And the megacorps were not having it, though it is worth noting how much effort AMD has been giving to support the open-source software community. https:\/\/www.phoronix.com\/news\/HDMI-2.1-OSS-Rejected By Michael Larabel One of the limitations of AMD&#8217;s open-source Linux graphics driver has been the inability to implement HDMI 2.1+ functionality on the basis of legal requirements by [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-6564","post","type-post","status-publish","format-standard","hentry","category-tech"],"blocksy_meta":[],"featured_image_src":null,"author_info":{"display_name":"Jason","author_link":"https:\/\/jasonsblog.ddns.net\/index.php\/author\/jturning\/"},"_links":{"self":[{"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/posts\/6564","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/comments?post=6564"}],"version-history":[{"count":1,"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/posts\/6564\/revisions"}],"predecessor-version":[{"id":6565,"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/posts\/6564\/revisions\/6565"}],"wp:attachment":[{"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/media?parent=6564"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/categories?post=6564"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jasonsblog.ddns.net\/index.php\/wp-json\/wp\/v2\/tags?post=6564"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}