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/diffconfig | 144 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100755 scripts/diffconfig (limited to 'scripts/diffconfig') diff --git a/scripts/diffconfig b/scripts/diffconfig new file mode 100755 index 000000000..43f0f3d27 --- /dev/null +++ b/scripts/diffconfig @@ -0,0 +1,144 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0 +# +# diffconfig - a tool to compare .config files. +# +# originally written in 2006 by Matt Mackall +# (at least, this was in his bloatwatch source code) +# last worked on 2008 by Tim Bird +# + +import sys, os + +def usage(): + print("""Usage: diffconfig [-h] [-m] [ ] + +Diffconfig is a simple utility for comparing two .config files. +Using standard diff to compare .config files often includes extraneous and +distracting information. This utility produces sorted output with only the +changes in configuration values between the two files. + +Added and removed items are shown with a leading plus or minus, respectively. +Changed items show the old and new values on a single line. + +If -m is specified, then output will be in "merge" style, which has the +changed and new values in kernel config option format. + +If no config files are specified, .config and .config.old are used. + +Example usage: + $ diffconfig .config config-with-some-changes +-EXT2_FS_XATTR n + CRAMFS n -> y + EXT2_FS y -> n + LOG_BUF_SHIFT 14 -> 16 + PRINTK_TIME n -> y +""") + sys.exit(0) + +# returns a dictionary of name/value pairs for config items in the file +def readconfig(config_file): + d = {} + for line in config_file: + line = line[:-1] + if line[:7] == "CONFIG_": + name, val = line[7:].split("=", 1) + d[name] = val + if line[-11:] == " is not set": + d[line[9:-11]] = "n" + return d + +def print_config(op, config, value, new_value): + global merge_style + + if merge_style: + if new_value: + if new_value=="n": + print("# CONFIG_%s is not set" % config) + else: + print("CONFIG_%s=%s" % (config, new_value)) + else: + if op=="-": + print("-%s %s" % (config, value)) + elif op=="+": + print("+%s %s" % (config, new_value)) + else: + print(" %s %s -> %s" % (config, value, new_value)) + +def show_diff(): + global merge_style + + # parse command line args + if ("-h" in sys.argv or "--help" in sys.argv): + usage() + + merge_style = 0 + if "-m" in sys.argv: + merge_style = 1 + sys.argv.remove("-m") + + argc = len(sys.argv) + if not (argc==1 or argc == 3): + print("Error: incorrect number of arguments or unrecognized option") + usage() + + if argc == 1: + # if no filenames given, assume .config and .config.old + build_dir="" + if "KBUILD_OUTPUT" in os.environ: + build_dir = os.environ["KBUILD_OUTPUT"]+"/" + configa_filename = build_dir + ".config.old" + configb_filename = build_dir + ".config" + else: + configa_filename = sys.argv[1] + configb_filename = sys.argv[2] + + try: + a = readconfig(open(configa_filename)) + b = readconfig(open(configb_filename)) + except (IOError): + e = sys.exc_info()[1] + print("I/O error[%s]: %s\n" % (e.args[0],e.args[1])) + usage() + + # print items in a but not b (accumulate, sort and print) + old = [] + for config in a: + if config not in b: + old.append(config) + old.sort() + for config in old: + print_config("-", config, a[config], None) + del a[config] + + # print items that changed (accumulate, sort, and print) + changed = [] + for config in a: + if a[config] != b[config]: + changed.append(config) + else: + del b[config] + changed.sort() + for config in changed: + print_config("->", config, a[config], b[config]) + del b[config] + + # now print items in b but not in a + # (items from b that were in a were removed above) + new = sorted(b.keys()) + for config in new: + print_config("+", config, None, b[config]) + +def main(): + try: + show_diff() + except BrokenPipeError: + # Python flushes standard streams on exit; redirect remaining output + # to devnull to avoid another BrokenPipeError at shutdown + devnull = os.open(os.devnull, os.O_WRONLY) + os.dup2(devnull, sys.stdout.fileno()) + sys.exit(1) # Python exits with error code 1 on EPIPE + + +if __name__ == '__main__': + main() -- cgit v1.3.1