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) --- scripts/check-sysctl-docs | 174 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 174 insertions(+) create mode 100755 scripts/check-sysctl-docs (limited to 'scripts/check-sysctl-docs') diff --git a/scripts/check-sysctl-docs b/scripts/check-sysctl-docs new file mode 100755 index 000000000..910fd8a9a --- /dev/null +++ b/scripts/check-sysctl-docs @@ -0,0 +1,174 @@ +#!/usr/bin/env -S gawk -f +# SPDX-License-Identifier: GPL-2.0 + +# Script to check sysctl documentation against source files +# +# Copyright (c) 2020 Stephen Kitt + +# Example invocation: +# scripts/check-sysctl-docs -vtable="kernel" \ +# Documentation/admin-guide/sysctl/kernel.rst \ +# $(git grep -l register_sysctl) +# +# Specify -vdebug=1 to see debugging information + +BEGIN { + if (!table) { + print "Please specify the table to look for using the table variable" > "/dev/stderr" + exit 1 + } + + # Documentation title skiplist + skiplist[0] = "^Documentation for" + skiplist[1] = "Network core options$" + skiplist[2] = "POSIX message queues filesystem$" + skiplist[3] = "Configuration options" + skiplist[4] = ". /proc/sys/fs" + skiplist[5] = "^Introduction$" + skiplist[6] = "^seccomp$" + skiplist[7] = "^pty$" + skiplist[8] = "^firmware_config$" + skiplist[9] = "^random$" +} + +# The following globals are used: +# documented: maps documented entries (each key is an entry) +# entries: maps ctl_table names and procnames to counts (so +# enumerating the subkeys for a given ctl_table lists its +# procnames) +# curtable: the name of the current ctl_table struct +# curentry: the name of the current proc entry (procname when parsing +# a ctl_table, constructed path when parsing a ctl_path) + + +# Remove punctuation from the given value +function trimpunct(value) { + while (value ~ /^["&]/) { + value = substr(value, 2) + } + while (value ~ /[]["&,}]$/) { + value = substr(value, 1, length(value) - 1) + } + return value +} + +# Print the information for the given entry +function printentry(entry) { + seen[entry]++ + printf "* %s from %s", entry, file[entry] + if (documented[entry]) { + printf " (documented)" + } + print "" +} + + +# Stage 1: build the list of documented entries +FNR == NR && /^=+$/ { + for (i in skiplist) { + if (prevline ~ skiplist[i]) { + next + } + } + + # The previous line is a section title, parse it + $0 = prevline + if (debug) print "Parsing " $0 + inbrackets = 0 + for (i = 1; i <= NF; i++) { + if (length($i) == 0) { + continue + } + if (!inbrackets && substr($i, 1, 1) == "(") { + inbrackets = 1 + } + if (!inbrackets) { + token = trimpunct($i) + if (length(token) > 0 && token != "and") { + if (debug) print trimpunct($i) + documented[trimpunct($i)]++ + } + } + if (inbrackets && substr($i, length($i), 1) == ")") { + inbrackets = 0 + } + } +} + +FNR == NR { + prevline = $0 + next +} + + +# Stage 2: process each file and find all sysctl tables +BEGINFILE { + delete entries + curtable = "" + curentry = "" + delete vars + if (debug) print "Processing file " FILENAME +} + +/^static( const)? struct ctl_table/ { + match($0, /static( const)? struct ctl_table ([^][]+)/, tables) + curtable = tables[2] + if (debug) print "Processing table " curtable +} + +/^};$/ { + curtable = "" + curentry = "" + delete vars +} + +curtable && /\.procname[\t ]*=[\t ]*".+"/ { + match($0, /.procname[\t ]*=[\t ]*"([^"]+)"/, names) + curentry = names[1] + if (debug) print "Adding entry " curentry " to table " curtable + entries[curtable][curentry]++ + file[curentry] = FILENAME +} + +curtable && /UCOUNT_ENTRY.*/ { + match($0, /UCOUNT_ENTRY\("([^"]+)"\)/, names) + curentry = names[1] + if (debug) print "Adding entry " curentry " to table " curtable + entries[curtable][curentry]++ + file[curentry] = FILENAME +} + +/register_sysctl.*/ { + match($0, /register_sysctl(|_init|_sz)\("([^"]+)" *, *([^,)]+)/, tables) + if (debug) print "Registering table " tables[3] " at " tables[2] + if (tables[2] == table) { + for (entry in entries[tables[3]]) { + printentry(entry) + } + } +} + +/kmemdup.*/ { + match($0, /([^ \t]+) *= *kmemdup\(([^,]+) *,/, names) + if (debug) print "Found variable " names[1] " for table " names[2] + if (names[2] in entries) { + vars[names[1]] = names[2] + } +} + +/__register_sysctl_table.*/ { + match($0, /__register_sysctl_table\([^,]+, *"([^"]+)" *, *([^,]+)/, tables) + if (debug) print "Registering variable table " tables[2] " at " tables[1] + if (tables[1] == table && tables[2] in vars) { + for (entry in entries[vars[tables[2]]]) { + printentry(entry) + } + } +} + +END { + for (entry in documented) { + if (!seen[entry]) + print "No implementation for " entry + } +} -- cgit v1.3.1