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, 218 insertions, 0 deletions

diff --git a/drivers/gpu/host1x/debug.c b/drivers/gpu/host1x/debug.c
new file mode 100644
index 000000000..b828f773f
--- /dev/null
+++ b/drivers/gpu/host1x/debug.c
@@ -0,0 +1,218 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2010 Google, Inc.
+ * Author: Erik Gilling <konkers@android.com>
+ *
+ * Copyright (C) 2011-2013 NVIDIA Corporation
+ */
+
+#include <linux/debugfs.h>
+#include <linux/pm_runtime.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
+
+#include <linux/io.h>
+
+#include "dev.h"
+#include "debug.h"
+#include "channel.h"
+
+static DEFINE_MUTEX(debug_lock);
+
+unsigned int host1x_debug_trace_cmdbuf;
+
+static pid_t host1x_debug_force_timeout_pid;
+static u32 host1x_debug_force_timeout_val;
+static u32 host1x_debug_force_timeout_channel;
+
+void host1x_debug_output(struct output *o, const char *fmt, ...)
+{
+	va_list args;
+	int len;
+
+	va_start(args, fmt);
+	len = vscnprintf(o->buf, sizeof(o->buf), fmt, args);
+	va_end(args);
+
+	o->fn(o->ctx, o->buf, len, false);
+}
+
+void host1x_debug_cont(struct output *o, const char *fmt, ...)
+{
+	va_list args;
+	int len;
+
+	va_start(args, fmt);
+	len = vscnprintf(o->buf, sizeof(o->buf), fmt, args);
+	va_end(args);
+
+	o->fn(o->ctx, o->buf, len, true);
+}
+
+static int show_channel(struct host1x_channel *ch, void *data, bool show_fifo)
+{
+	struct host1x *m = dev_get_drvdata(ch->dev->parent);
+	struct output *o = data;
+	int err;
+
+	err = pm_runtime_resume_and_get(m->dev);
+	if (err < 0)
+		return err;
+
+	mutex_lock(&ch->cdma.lock);
+	mutex_lock(&debug_lock);
+
+	if (show_fifo)
+		host1x_hw_show_channel_fifo(m, ch, o);
+
+	host1x_hw_show_channel_cdma(m, ch, o);
+
+	mutex_unlock(&debug_lock);
+	mutex_unlock(&ch->cdma.lock);
+
+	pm_runtime_put(m->dev);
+
+	return 0;
+}
+
+static void show_syncpts(struct host1x *m, struct output *o, bool show_all)
+{
+	unsigned long irqflags;
+	struct list_head *pos;
+	unsigned int i;
+	int err;
+
+	host1x_debug_output(o, "---- syncpts ----\n");
+
+	err = pm_runtime_resume_and_get(m->dev);
+	if (err < 0)
+		return;
+
+	for (i = 0; i < host1x_syncpt_nb_pts(m); i++) {
+		u32 max = host1x_syncpt_read_max(m->syncpt + i);
+		u32 min = host1x_syncpt_load(m->syncpt + i);
+		unsigned int waiters = 0;
+
+		spin_lock_irqsave(&m->syncpt[i].fences.lock, irqflags);
+		list_for_each(pos, &m->syncpt[i].fences.list)
+			waiters++;
+		spin_unlock_irqrestore(&m->syncpt[i].fences.lock, irqflags);
+
+		if (!kref_read(&m->syncpt[i].ref))
+			continue;
+
+		if (!show_all && !min && !max && !waiters)
+			continue;
+
+		host1x_debug_output(o,
+				    "id %u (%s) min %d max %d (%d waiters)\n",
+				    i, m->syncpt[i].name, min, max, waiters);
+	}
+
+	for (i = 0; i < host1x_syncpt_nb_bases(m); i++) {
+		u32 base_val;
+
+		base_val = host1x_syncpt_load_wait_base(m->syncpt + i);
+		if (base_val)
+			host1x_debug_output(o, "waitbase id %u val %d\n", i,
+					    base_val);
+	}
+
+	pm_runtime_put(m->dev);
+
+	host1x_debug_output(o, "\n");
+}
+
+static void show_all(struct host1x *m, struct output *o, bool show_fifo)
+{
+	unsigned int i;
+
+	host1x_hw_show_mlocks(m, o);
+	show_syncpts(m, o, true);
+	host1x_debug_output(o, "---- channels ----\n");
+
+	for (i = 0; i < m->info->nb_channels; ++i) {
+		struct host1x_channel *ch = host1x_channel_get_index(m, i);
+
+		if (ch) {
+			show_channel(ch, o, show_fifo);
+			host1x_channel_put(ch);
+		}
+	}
+}
+
+static int host1x_debug_all_show(struct seq_file *s, void *unused)
+{
+	struct output o = {
+		.fn = write_to_seqfile,
+		.ctx = s
+	};
+
+	show_all(s->private, &o, true);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(host1x_debug_all);
+
+static int host1x_debug_show(struct seq_file *s, void *unused)
+{
+	struct output o = {
+		.fn = write_to_seqfile,
+		.ctx = s
+	};
+
+	show_all(s->private, &o, false);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(host1x_debug);
+
+static void host1x_debugfs_init(struct host1x *host1x)
+{
+	struct dentry *de = debugfs_create_dir("tegra-host1x", NULL);
+
+	/* Store the created entry */
+	host1x->debugfs = de;
+
+	debugfs_create_file("status", S_IRUGO, de, host1x, &host1x_debug_fops);
+	debugfs_create_file("status_all", S_IRUGO, de, host1x,
+			    &host1x_debug_all_fops);
+
+	debugfs_create_u32("trace_cmdbuf", S_IRUGO|S_IWUSR, de,
+			   &host1x_debug_trace_cmdbuf);
+
+	host1x_hw_debug_init(host1x, de);
+
+	debugfs_create_u32("force_timeout_pid", S_IRUGO|S_IWUSR, de,
+			   &host1x_debug_force_timeout_pid);
+	debugfs_create_u32("force_timeout_val", S_IRUGO|S_IWUSR, de,
+			   &host1x_debug_force_timeout_val);
+	debugfs_create_u32("force_timeout_channel", S_IRUGO|S_IWUSR, de,
+			   &host1x_debug_force_timeout_channel);
+}
+
+static void host1x_debugfs_exit(struct host1x *host1x)
+{
+	debugfs_remove_recursive(host1x->debugfs);
+}
+
+void host1x_debug_init(struct host1x *host1x)
+{
+	if (IS_ENABLED(CONFIG_DEBUG_FS))
+		host1x_debugfs_init(host1x);
+}
+
+void host1x_debug_deinit(struct host1x *host1x)
+{
+	if (IS_ENABLED(CONFIG_DEBUG_FS))
+		host1x_debugfs_exit(host1x);
+}
+
+void host1x_debug_dump(struct host1x *host1x)
+{
+	struct output o = {
+		.fn = write_to_printk
+	};
+
+	show_all(host1x, &o, true);
+}