From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E2E70606A329 for ; Sat, 14 Nov 2026 02:50:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QYItl27q Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0D7E510E1F0; Sat, 14 Nov 2026 02:50:05 +0000 (UTC) Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id BA0E610E1F0 for ; Sat, 14 Nov 2026 02:49:58 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 67744417F3 for ; Sat, 14 Nov 2026 02:49:58 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPS id 4B51C1F000C5 for ; Sat, 14 Nov 2026 02:49:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794624598; bh=UizdDx/yb95rK0tTi0afEM4sxMr92PJ3xZkPFHYq/Yw=; h=From:To:Subject:Date; b=QYItl27qLYx9MZa3CMDb7CDYhEEmTZisxkIrGAtQYs0OG7X5N4taFuBvDycpZ8lg8 BVMIjCpC9uWgjP0GqbxB1v63YgaVnQIRMbc1iPVoWVd779tBGob9UqLslYe3TTVikf 4sX2pkqprbmofxbdRCQS1l4oAk2px/Rmn/WuW7AeEc9um01Piwfy4c75C0AkyODmXD W32MOu9u6rRqvdCiHafzX6NdldT7a12sG2fb6DHem15LolspA0CVA2/hpNzi55iNa7 3AgrvxPvzikInoOGxJ+PB1FP9oluHFUwX22HJX+PFP61EI58YK+kHrF9cDx9N3+rmq g41/fdbXoRbvg== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 43552C41612; Sat, 14 Nov 2026 02:49:58 +0000 (UTC) From: bugzilla-daemon@kernel.org To: dri-devel@lists.freedesktop.org Subject: [Bug 222265] New: amdgpu: RX 7600 defaults to limited RGB range (washed-out blacks) over HDMI since kernel 7.3.4 Date: Sat, 14 Nov 2026 02:49:57 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: AssignedTo drivers_video-dri@kernel-bugs.osdl.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: Video(DRI - non Intel) X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: mister.freeman@laposte.net X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: drivers_video-dri@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version cf_kernel_version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter cf_regression attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated X-Archived-By: MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "dri-devel" X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 https://bugzilla.kernel.org/show_bug.cgi?id=3D222265 Bug ID: 222265 Summary: amdgpu: RX 7600 defaults to limited RGB range (washed-out blacks) over HDMI since kernel 7.3.4 Product: Drivers Version: 2.5 Kernel Version: 7.3 Hardware: All OS: Linux Status: NEW Severity: normal Priority: P3 Component: Video(DRI - non Intel) Assignee: drivers_video-dri@kernel-bugs.osdl.org Reporter: mister.freeman@laposte.net Regression: Yes Created attachment 311464 --> https://bugzilla.kernel.org/attachment.cgi?id=3D311464&action=3Dedit Attaching the original unmodified 256-byte EDID binary (`original_edid.bin`) from the Iiyama ProLite X2483/X2481 monitor Starting with Linux kernel 7.3.4, my AMD Radeon RX 7600 outputs washed-out blacks (greyish blacks, indicative of limited RGB range 16-235 or incorrect color format negotiation) over HDMI (`HDMI-A-1`) immediately at early KMS b= oot, prior to any display manager or Wayland compositor loading. Hardware & Software Environment - **Distribution:** Arch Linux (up to date) - **Kernel version:** 7.3.4 (Regression; previous kernels / LTS work proper= ly) - **GPU:** AMD Radeon RX 7600 (RDNA 3 / Navi 33) - **Connection:** HDMI (`HDMI-A-1`) - **Monitor:** Iiyama ProLite X2483/X2481 (1920x1080 @ 60Hz, EDID 1.3 with CTA-861 extension block) - **Desktop Environment:** KDE Plasma (Wayland) / Plasma Login Manager ### Steps to Reproduce 1. Boot Linux kernel 7.3.4 with `amdgpu` enabled (early KMS). 2. Observe the TTY console and login screen on the HDMI monitor before any = user session overrides DRM properties. ### Actual Results Black levels appear washed out (dark grey) right from kernel mode-setting initialization at boot. ### Expected Results The `amdgpu` driver should negotiate and output Full RGB range (0-255) by default on a standard PC monitor over HDMI, producing true deep blacks from early boot. ### Workarounds & Diagnostic Findings 1. **Desktop Compositor Override:** Manually changing the "RGB Range" prope= rty from "Automatic" to "Full" inside KDE Plasma Display Settings immediately f= ixes the blacks once the desktop session starts. This confirms the default autom= atic negotiation in `amdgpu` 7.3.x is selecting Limited RGB (16-235) instead of = Full RGB (0-255). 2. **EDID Override (CTA-861 removal):** Stripping the CTA-861 extension blo= ck from the monitor's EDID (reducing it to a 128-byte Base EDID block without CEA/HDMI extensions) and loading it via `drm.edid_firmware=3Dedid/custom.bi= n` forces `amdgpu` to treat the display as a DVI/PC monitor and restores Full = RGB range (true blacks) immediately at boot. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=