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, 262 insertions, 0 deletions

diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
new file mode 100644
index 000000000..2691a5da3
--- /dev/null
+++ b/drivers/md/bcache/debug.c
@@ -0,0 +1,262 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Assorted bcache debug code
+ *
+ * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
+ * Copyright 2012 Google, Inc.
+ */
+
+#include "bcache.h"
+#include "btree.h"
+#include "debug.h"
+#include "extents.h"
+
+#include <linux/console.h>
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/seq_file.h>
+
+struct dentry *bcache_debug;
+
+#ifdef CONFIG_BCACHE_DEBUG
+
+#define for_each_written_bset(b, start, i)				\
+	for (i = (start);						\
+	     (void *) i < (void *) (start) + (KEY_SIZE(&b->key) << 9) &&\
+	     i->seq == (start)->seq;					\
+	     i = (void *) i + set_blocks(i, block_bytes(b->c->cache)) *	\
+		 block_bytes(b->c->cache))
+
+void bch_btree_verify(struct btree *b)
+{
+	struct btree *v = b->c->verify_data;
+	struct bset *ondisk, *sorted, *inmemory;
+	struct bio *bio;
+
+	if (!b->c->verify || !b->c->verify_ondisk)
+		return;
+
+	down(&b->io_mutex);
+	mutex_lock(&b->c->verify_lock);
+
+	ondisk = b->c->verify_ondisk;
+	sorted = b->c->verify_data->keys.set->data;
+	inmemory = b->keys.set->data;
+
+	bkey_copy(&v->key, &b->key);
+	v->written = 0;
+	v->level = b->level;
+	v->keys.ops = b->keys.ops;
+
+	bio = bch_bbio_alloc(b->c);
+	bio_set_dev(bio, b->c->cache->bdev);
+	bio->bi_iter.bi_sector	= PTR_OFFSET(&b->key, 0);
+	bio->bi_iter.bi_size	= KEY_SIZE(&v->key) << 9;
+	bio->bi_opf		= REQ_OP_READ | REQ_META;
+	bch_bio_map(bio, sorted);
+
+	submit_bio_wait(bio);
+	bch_bbio_free(bio, b->c);
+
+	memcpy(ondisk, sorted, KEY_SIZE(&v->key) << 9);
+
+	bch_btree_node_read_done(v);
+	sorted = v->keys.set->data;
+
+	if (inmemory->keys != sorted->keys ||
+	    memcmp(inmemory->start,
+		   sorted->start,
+		   (void *) bset_bkey_last(inmemory) -
+		   (void *) inmemory->start)) {
+		struct bset *i;
+		unsigned int j;
+
+		console_lock();
+
+		pr_err("*** in memory:\n");
+		bch_dump_bset(&b->keys, inmemory, 0);
+
+		pr_err("*** read back in:\n");
+		bch_dump_bset(&v->keys, sorted, 0);
+
+		for_each_written_bset(b, ondisk, i) {
+			unsigned int block = ((void *) i - (void *) ondisk) /
+				block_bytes(b->c->cache);
+
+			pr_err("*** on disk block %u:\n", block);
+			bch_dump_bset(&b->keys, i, block);
+		}
+
+		pr_err("*** block %zu not written\n",
+		       ((void *) i - (void *) ondisk) / block_bytes(b->c->cache));
+
+		for (j = 0; j < inmemory->keys; j++)
+			if (inmemory->d[j] != sorted->d[j])
+				break;
+
+		pr_err("b->written %u\n", b->written);
+
+		console_unlock();
+		panic("verify failed at %u\n", j);
+	}
+
+	mutex_unlock(&b->c->verify_lock);
+	up(&b->io_mutex);
+}
+
+void bch_data_verify(struct cached_dev *dc, struct bio *bio)
+{
+	unsigned int nr_segs = bio_segments(bio);
+	struct bio *check;
+	struct bio_vec bv, cbv;
+	struct bvec_iter iter, citer = { 0 };
+
+	check = bio_kmalloc(nr_segs, GFP_NOIO);
+	if (!check)
+		return;
+	bio_init_inline(check, bio->bi_bdev, nr_segs, REQ_OP_READ);
+	check->bi_iter.bi_sector = bio->bi_iter.bi_sector;
+	check->bi_iter.bi_size = bio->bi_iter.bi_size;
+
+	bch_bio_map(check, NULL);
+	if (bch_bio_alloc_pages(check, GFP_NOIO))
+		goto out_put;
+
+	submit_bio_wait(check);
+
+	citer.bi_size = UINT_MAX;
+	bio_for_each_segment(bv, bio, iter) {
+		void *p1 = bvec_kmap_local(&bv);
+		void *p2;
+
+		cbv = bio_iter_iovec(check, citer);
+		p2 = bvec_kmap_local(&cbv);
+
+		cache_set_err_on(memcmp(p1, p2, bv.bv_len),
+				 dc->disk.c,
+				 "verify failed at dev %pg sector %llu",
+				 dc->bdev,
+				 (uint64_t) bio->bi_iter.bi_sector);
+
+		kunmap_local(p2);
+		kunmap_local(p1);
+		bio_advance_iter(check, &citer, bv.bv_len);
+	}
+
+	bio_free_pages(check);
+out_put:
+	bio_uninit(check);
+	kfree(check);
+}
+
+#endif
+
+#ifdef CONFIG_DEBUG_FS
+
+/* XXX: cache set refcounting */
+
+struct dump_iterator {
+	char			buf[PAGE_SIZE];
+	size_t			bytes;
+	struct cache_set	*c;
+	struct keybuf		keys;
+};
+
+static bool dump_pred(struct keybuf *buf, struct bkey *k)
+{
+	return true;
+}
+
+static ssize_t bch_dump_read(struct file *file, char __user *buf,
+			     size_t size, loff_t *ppos)
+{
+	struct dump_iterator *i = file->private_data;
+	ssize_t ret = 0;
+	char kbuf[80];
+
+	while (size) {
+		struct keybuf_key *w;
+		unsigned int bytes = min(i->bytes, size);
+
+		if (copy_to_user(buf, i->buf, bytes))
+			return -EFAULT;
+
+		ret	 += bytes;
+		buf	 += bytes;
+		size	 -= bytes;
+		i->bytes -= bytes;
+		memmove(i->buf, i->buf + bytes, i->bytes);
+
+		if (i->bytes)
+			break;
+
+		w = bch_keybuf_next_rescan(i->c, &i->keys, &MAX_KEY, dump_pred);
+		if (!w)
+			break;
+
+		bch_extent_to_text(kbuf, sizeof(kbuf), &w->key);
+		i->bytes = snprintf(i->buf, PAGE_SIZE, "%s\n", kbuf);
+		bch_keybuf_del(&i->keys, w);
+	}
+
+	return ret;
+}
+
+static int bch_dump_open(struct inode *inode, struct file *file)
+{
+	struct cache_set *c = inode->i_private;
+	struct dump_iterator *i;
+
+	i = kzalloc_obj(struct dump_iterator);
+	if (!i)
+		return -ENOMEM;
+
+	file->private_data = i;
+	i->c = c;
+	bch_keybuf_init(&i->keys);
+	i->keys.last_scanned = KEY(0, 0, 0);
+
+	return 0;
+}
+
+static int bch_dump_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+static const struct file_operations cache_set_debug_ops = {
+	.owner		= THIS_MODULE,
+	.open		= bch_dump_open,
+	.read		= bch_dump_read,
+	.release	= bch_dump_release
+};
+
+void bch_debug_init_cache_set(struct cache_set *c)
+{
+	if (!IS_ERR_OR_NULL(bcache_debug)) {
+		char name[50];
+
+		snprintf(name, 50, "bcache-%pU", c->set_uuid);
+		c->debug = debugfs_create_file(name, 0400, bcache_debug, c,
+					       &cache_set_debug_ops);
+	}
+}
+
+#endif
+
+void bch_debug_exit(void)
+{
+	debugfs_remove_recursive(bcache_debug);
+}
+
+void __init bch_debug_init(void)
+{
+	/*
+	 * it is unnecessary to check return value of
+	 * debugfs_create_file(), we should not care
+	 * about this.
+	 */
+	bcache_debug = debugfs_create_dir("bcache", NULL);
+}