From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- .../access-controllers/access-controllers.yaml | 84 ++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 Documentation/devicetree/bindings/access-controllers/access-controllers.yaml (limited to 'Documentation/devicetree/bindings/access-controllers') diff --git a/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml b/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml new file mode 100644 index 000000000..99e2865f0 --- /dev/null +++ b/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml @@ -0,0 +1,84 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/access-controllers/access-controllers.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic Domain Access Controllers + +maintainers: + - Oleksii Moisieiev + +description: |+ + Common access controllers properties + + Access controllers are in charge of stating which of the hardware blocks under + their responsibility (their domain) can be accesssed by which compartment. A + compartment can be a cluster of CPUs (or coprocessors), a range of addresses + or a group of hardware blocks. An access controller's domain is the set of + resources covered by the access controller. + + This device tree binding can be used to bind devices to their access + controller provided by access-controllers property. In this case, the device + is a consumer and the access controller is the provider. + + An access controller can be represented by any node in the device tree and + can provide one or more configuration parameters, needed to control parameters + of the consumer device. A consumer node can refer to the provider by phandle + and a set of phandle arguments, specified by '#access-controller-cells' + property in the access controller node. + + Access controllers are typically used to set/read the permissions of a + hardware block and grant access to it. Any of which depends on the access + controller. The capabilities of each access controller are defined by the + binding of the access controller device. + + Each node can be a consumer for the several access controllers. + +# always select the core schema +select: true + +properties: + "#access-controller-cells": + description: + Number of cells in an access-controllers specifier; + Can be any value as specified by device tree binding documentation + of a particular provider. The node is an access controller. + + access-controller-names: + $ref: /schemas/types.yaml#/definitions/string-array + description: + A list of access-controllers names, sorted in the same order as + access-controllers entries. Consumer drivers will use + access-controller-names to match with existing access-controllers entries. + + access-controllers: + $ref: /schemas/types.yaml#/definitions/phandle-array + description: + A list of access controller specifiers, as defined by the + bindings of the access-controllers provider. + +additionalProperties: true + +examples: + - | + clock_controller: access-controllers@50000 { + reg = <0x50000 0x400>; + #access-controller-cells = <2>; + }; + + bus_controller: bus@60000 { + reg = <0x60000 0x10000>; + #address-cells = <1>; + #size-cells = <1>; + ranges; + #access-controller-cells = <3>; + + uart4: serial@60100 { + reg = <0x60100 0x400>; + clocks = <&clk_serial>; + access-controllers = <&clock_controller 1 2>, + <&bus_controller 1 3 5>; + access-controller-names = "clock", "bus"; + }; + }; -- cgit v1.3.1