drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted

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 <adolfotregosa@gmail.com>
Assisted-by: Claude Code:claude-fable-5-1
Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch>
Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)

1 files changed, 418 insertions, 0 deletions

diff --git a/Documentation/sphinx/maintainers_include.py b/Documentation/sphinx/maintainers_include.py
new file mode 100755
index 000000000..7ffe19b5e
--- /dev/null
+++ b/Documentation/sphinx/maintainers_include.py
@@ -0,0 +1,418 @@
+#!/usr/bin/env python
+# SPDX-License-Identifier: GPL-2.0
+# -*- coding: utf-8; mode: python -*-
+# pylint: disable=C0209, C0301, E0401, R0022, R0902, R0903, R0912, R0914
+
+"""
+Implementation of the ``maintainers-include`` reST-directive.
+
+:copyright:  Copyright (C) 2019  Kees Cook <keescook@chromium.org>
+:license:    GPL Version 2, June 1991 see linux/COPYING for details.
+
+The ``maintainers-include`` reST-directive performs extensive parsing
+specific to the Linux kernel's standard "MAINTAINERS" file, in an
+effort to avoid needing to heavily mark up the original plain text.
+"""
+
+import os.path
+import re
+
+from glob import glob
+
+from docutils import statemachine
+from docutils.parsers.rst.directives.misc import Include
+
+#
+# Base URL for intersphinx-like links to maintainer profiles
+#
+KERNELDOC_URL = "https://docs.kernel.org/"
+
+__version__ = "1.0"
+
+maint_parser = None  # pylint: disable=C0103
+
+JS_FILTER = """
+(function() {
+  function filterTable(table) {
+    const filter = document.getElementById("filter-table").value.trim();
+    const rows = table.querySelectorAll("tbody tr");
+    for (let i = 0; i < rows.length; i++) {
+      const tds = rows[i].getElementsByTagName("td");
+      let match = false;
+      for (let j = 0; j < tds.length; j++) {
+        const cellText = (tds[j].textContent || tds[j].innerText);
+        if (cellText.includes(filter)) {
+          match = true;
+          break;
+        }
+      }
+      rows[i].style.display = match ? "table-row" : "none";
+    }
+  }
+  function addInput() {
+    const table = document.getElementById("maintainers-table");
+    if (!table) return;
+    let input = document.getElementById("filter-table");
+    if (!input) {
+      const filt_div = document.createElement('div');
+      filt_div.innerHTML = `
+        <p>Filter:
+          <input type="search" id="filter-table" placeholder="search string"/>
+          subsystem or property (case-sensitive)
+        </p>
+      `;
+      table.parentNode.insertBefore(filt_div, table);
+      const input = document.getElementById("filter-table")
+      input.addEventListener('input', () => filterTable(table));
+    }
+  }
+  if (document.readyState === 'loading') {
+    document.addEventListener('DOMContentLoaded', addInput);
+  } else {
+    addInput();
+  }
+})();
+"""
+
+
+# Shamelessly stolen from docutils
+def ErrorString(exc):  # pylint: disable=C0103, C0116
+    return f"{exc.__class__.__name}: {exc}"  # pylint: disable=W0212
+
+class MaintainersParser:
+    """Parse MAINTAINERS file(s) content"""
+
+    def __init__(self, base_dir, app_dir, path):
+        self.path = path
+
+        # Poor man's state machine.
+        self.descriptions = False
+        self.maintainers = False
+        self.subsystems = False
+
+        self.subsystem_name = None
+
+        self.base_dir = base_dir
+        self.app_dir = app_dir
+
+        self.re_doc = re.compile(r'(Documentation/(\S*)\.rst)')
+
+        #
+        # Output variables with maintainers content to be stored
+        #
+        self.profile_toc = set()
+        self.profile_entries = {}
+        self.header = ""
+        self.maint_entries = {}
+        self.fields = {}
+
+        prev = None
+        with open(path, "r", encoding="utf-8") as fp:
+            for line in fp:
+                if self.descriptions:
+                    self.parse_descriptions(line)
+                elif self.maintainers and not self.subsystems:
+                    if re.search('^[A-Z0-9]', line):
+                        self.subsystems = True
+                        self.parse_subsystems(line)
+                    else:
+                        self.header += line
+                elif self.subsystems:
+                    self.parse_subsystems(line)
+                else:
+                    self.header += line
+
+                # Update the state machine when we find heading separators.
+                if line.startswith("----------"):
+                    if prev.startswith("Descriptions"):
+                        self.descriptions = True
+                    if prev.startswith("Maintainers"):
+                        self.maintainers = True
+
+                # Retain previous line for state machine transitions.
+                prev = line
+
+    def get_entries(self, text):
+        """Generate refs to ReST files in Documentation/"""
+
+        if "Documentation/" not in text:
+            return None
+
+        if "*" in text or "?" in text:
+            m = self.re_doc.search(text)
+            if not m:
+                return None
+
+            doc_list = glob(os.path.join(self.base_dir, m.group(1)))
+        else:
+            doc_list = [text]
+
+        entries = {}
+        for doc in doc_list:
+            m = self.re_doc.search(doc)
+            if m:
+                fname = m.group(1)
+                ename = m.group(2)
+
+                entry = os.path.relpath(self.base_dir + fname, self.app_dir)
+                entry = entry.removesuffix(".rst")
+
+                if entry.startswith("../"):
+                    html = KERNELDOC_URL + ename + ".html"
+                    entries[entry] = f'`{ename} <{html}>`_'
+                else:
+                    entries[entry] = f'/{entry}'
+
+        return entries
+
+    def linkify(self, text):
+        """Return a list of doc files converted to cross-references"""
+
+        entries = self.get_entries(text)
+        if not entries:
+            return text
+
+        return self.re_doc.sub(", ".join(entries.values()), text)
+
+    def parse_descriptions(self, line):
+        """Handle contents of the descriptions section."""
+
+        # Have we reached the end of the preformatted Descriptions text?
+        if line.startswith("Maintainers"):
+            self.descriptions = False
+            self.header += "\n" + line
+            return
+
+        # Look for and record field letter to field name mappings:
+        #   R: Designated *reviewer*: FullName <address@domain>
+        m = re.match(r"\s+(\S):\s+(\S+)", line)
+        if m:
+            field = m.group(1)
+            details = m.group(2)
+
+            if field not in self.fields:
+                m = re.search(r"\*([^\*]+)\*", line)
+                if m:
+                    self.fields[field] = m.group(1)
+            elif field in ['F', 'N', 'X', 'K']:
+                line = line.replace(details, f'``{details}``')
+
+        self.header += "| " + self.linkify(line)
+
+
+    def parse_subsystems(self, line):
+        """Handle contents of the per-subsystem sections."""
+
+        # Drop needless input whitespace.
+        line = line.rstrip()
+
+        # Skip empty lines: subsystem parser adds them as needed.
+        if not line:
+            return
+
+        if line[1] != ':':
+            self.subsystem_name = re.sub(r"\s+", " ", self.linkify(line))
+            return
+
+        # Render a subsystem field as:
+        #   :Field: entry
+        #           entry...
+        field, details = line.split(":", 1)
+        details = details.strip()
+
+        #
+        # Handle profile entries - either as files or as https refs
+        #
+        if field == "P":
+            entries = self.get_entries(details)
+            if entries:
+                for e, link in entries.items():
+                    if "html" not in link:
+                        self.profile_toc.add(e)
+
+                    self.profile_entries[self.subsystem_name] = link
+
+                details = ", ".join(entries.values())
+            else:
+                match = re.match(r"(https?://.*)", details)
+                if match:
+                    entry = match.group(1).strip()
+                    self.profile_entries[self.subsystem_name] = entry
+                else:
+                    self.profile_entries[self.subsystem_name] = f"``{details}``"
+
+                details = self.linkify(details)
+        else:
+            details = self.linkify(details)
+
+        #
+        # Mark paths (and regexes) as literal text for improved
+        # readability and to escape any escapes.
+        #
+        if field in ['F', 'N', 'X', 'K']:
+            # But only if not already marked :)
+            if ':doc:' not in details and "http" not in details:
+                details = '``%s``' % (details)
+
+        if self.subsystem_name not in self.maint_entries:
+            self.maint_entries[self.subsystem_name] = {}
+
+        if field not in self.maint_entries[self.subsystem_name]:
+            self.maint_entries[self.subsystem_name][field] = []
+
+        self.maint_entries[self.subsystem_name][field].append(details)
+
+        self.field_prev = field
+
+
+class MaintainersInclude(Include):
+    """MaintainersInclude (``maintainers-include``) directive"""
+
+    required_arguments = 0
+
+    def emit(self):
+        """Parse all the MAINTAINERS lines into ReST for human-readability"""
+        path = maint_parser.path
+        output = ".. _maintainers:\n\n"
+        output += maint_parser.header
+
+        output += ".. _maintainers_table:\n\n"
+        output += ".. flat-table::\n"
+        output += "  :header-rows: 1\n\n"
+        output += "  * - Subsystem\n"
+        output += "    - Properties\n\n"
+
+        self.state.document['maintainers_included'] = True
+
+        # Keep the last entry ("THE REST") in the end
+        entries = list(maint_parser.maint_entries.keys())
+        entries = sorted(entries[:-1], key=str.casefold) + [entries[-1]]
+
+        for name in entries:
+            fields = maint_parser.maint_entries[name]
+            output += f"  * - {name}\n"
+            tag = "-"
+            for field, lines in fields.items():
+                field_name = maint_parser.fields.get(field, field)
+
+                output += f"    {tag} :{field_name}:\n        "
+                output += ",\n        ".join(lines) + "\n"
+                tag = " "
+
+            output += "\n"
+
+        # For debugging the pre-rendered results...
+        #print(output, file=open("/tmp/MAINTAINERS.rst", "w"))
+
+        self.state.document.settings.record_dependencies.add(path)
+        self.state_machine.insert_input(statemachine.string2lines(output), path)
+
+    def run(self):
+        """Include the MAINTAINERS file as part of this reST file."""
+        if not self.state.document.settings.file_insertion_enabled:
+            raise self.warning('"%s" directive disabled.' % self.name)
+
+        try:
+            self.emit()
+        except IOError as error:
+            raise self.severe('Problems with "%s" directive path:\n%s.' %
+                      (self.name, ErrorString(error)))
+
+        return []
+
+
+class MaintainersProfile(Include):
+    """Generate a list with all maintainer's profiles"""
+
+    required_arguments = 0
+
+    def emit(self):
+        """Parse all the MAINTAINERS lines looking for profile entries"""
+        env = self.state.document.settings.env
+        docdir = os.path.dirname(os.path.join(env.srcdir, env.docname))
+        path = maint_parser.path
+
+        #
+        # Produce a list with all maintainer profiles, sorted by subsystem name
+        #
+        output = ""
+        for profile, entry in sorted(maint_parser.profile_entries.items()):
+            name = profile.title()
+
+            if entry.startswith("http"):
+                output += f"- `{name} <{entry}>`_\n"
+            elif entry.startswith("`"):
+                output += f"- {name}: {entry}\n"
+                self.warning(f"{profile}: Invalid 'P' tag: {entry}\n")
+            else:
+                if not name:
+                    name = entry
+
+                output += f"- :doc:`{name} <{entry}>`\n"
+
+        #
+        # Create a hidden TOC table with all profiles. That allows adding
+        # profiles without needing to add them on any index.rst file.
+        #
+        output += "\n.. toctree::\n"
+        output += "   :hidden:\n\n"
+
+        for f in sorted(maint_parser.profile_toc):
+            fname = os.path.join(maint_parser.base_dir, "Documentation", f)
+            fname = os.path.relpath(fname, docdir)
+            output += f"   {fname}\n"
+
+        output += "\n"
+
+        # For debugging the pre-rendered results...
+        #print(output, file=open("/tmp/profiles.rst", "w"))
+
+        self.state.document.settings.record_dependencies.add(path)
+        self.state_machine.insert_input(statemachine.string2lines(output), path)
+
+    def run(self):
+        """Include the MAINTAINERS file as part of this reST file."""
+        if not self.state.document.settings.file_insertion_enabled:
+            raise self.warning('"%s" directive disabled.' % self.name)
+
+        try:
+            self.emit()
+        except IOError as error:
+            raise self.severe('Problems with "%s" directive path:\n%s.' %
+                      (self.name, ErrorString(error)))
+
+        return []
+
+
+# pylint: disable=W0613
+def add_filter_script(app, pagename, templatename, context, doctree):
+    """Add Filter javascript only to maintainers page"""
+
+    if doctree and doctree.get('maintainers_included'):
+        app.add_js_file(None, body=JS_FILTER)
+
+
+def setup(app):
+    """Setup Sphinx extension"""
+    global maint_parser  # pylint: disable=W0603
+
+    app_dir = os.path.abspath(app.srcdir)
+    match = re.match(r"(.*/)Documentation", app_dir)
+    if not match:
+        raise ValueError('Documentation directory not found.')
+
+    base_dir = match.group(1)
+    path = os.path.join(base_dir, "MAINTAINERS")
+
+    maint_parser = MaintainersParser(base_dir, app_dir, path)
+
+    app.add_directive("maintainers-include", MaintainersInclude)
+    app.add_directive("maintainers-profile-toc", MaintainersProfile)
+
+    app.connect("html-page-context", add_filter_script)
+
+    return {
+        "version": __version__,
+        "parallel_read_safe": True,
+        "parallel_write_safe": True,
+    }