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)

13 files changed, 65 insertions, 0 deletions

diff --git a/usr/dummy-include/endian.h b/usr/dummy-include/endian.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/endian.h
diff --git a/usr/dummy-include/limits.h b/usr/dummy-include/limits.h
new file mode 100644
index 000000000..49b17c10c
--- /dev/null
+++ b/usr/dummy-include/limits.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_LIMITS_H
+#define _DUMMY_LIMITS_H
+
+#define INT_MAX ((int)(~0U >> 1))
+#define INT_MIN (-INT_MAX - 1)
+
+#endif /* _DUMMY_LIMITS_H */
diff --git a/usr/dummy-include/netinet/if_ether.h b/usr/dummy-include/netinet/if_ether.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/netinet/if_ether.h
diff --git a/usr/dummy-include/netinet/in.h b/usr/dummy-include/netinet/in.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/netinet/in.h
diff --git a/usr/dummy-include/stddef.h b/usr/dummy-include/stddef.h
new file mode 100644
index 000000000..525489daf
--- /dev/null
+++ b/usr/dummy-include/stddef.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_STDDEF_H
+#define _DUMMY_STDDEF_H
+
+#define offsetof(TYPE, MEMBER)	__builtin_offsetof(TYPE, MEMBER)
+
+#ifdef __cplusplus
+#define NULL 0
+#else
+#define NULL ((void *)0)
+#endif
+
+#endif /* _DUMMY_STDDEF_H */
diff --git a/usr/dummy-include/stdint.h b/usr/dummy-include/stdint.h
new file mode 100644
index 000000000..93b1962fd
--- /dev/null
+++ b/usr/dummy-include/stdint.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_STDINT_H
+#define _DUMMY_STDINT_H
+
+#include <linux/types.h>
+
+typedef	__u64	uint64_t;
+typedef	__u32	uint32_t;
+typedef	__u16	uint16_t;
+typedef	__u8	uint8_t;
+
+typedef	__s64	int64_t;
+typedef	__s32	int32_t;
+typedef	__s16	int16_t;
+typedef	__s8	int8_t;
+
+#endif /* _DUMMY_STDINT_H */
diff --git a/usr/dummy-include/string.h b/usr/dummy-include/string.h
new file mode 100644
index 000000000..e059808d3
--- /dev/null
+++ b/usr/dummy-include/string.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_STRING_H
+#define _DUMMY_STRING_H
+
+#include <stddef.h>
+
+#define memset(_s, _c, _n) __builtin_memset(_s, _c, _n)
+#define memcpy(_dest, _src, _n) __builtin_memcpy(_dest, _src, _n)
+
+#define strlen(_s) __builtin_strlen(_s)
+
+#endif /* _DUMMY_STRING_H */
diff --git a/usr/dummy-include/sys/ioctl.h b/usr/dummy-include/sys/ioctl.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/sys/ioctl.h
diff --git a/usr/dummy-include/sys/socket.h b/usr/dummy-include/sys/socket.h
new file mode 100644
index 000000000..748751f9e
--- /dev/null
+++ b/usr/dummy-include/sys/socket.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _DUMMY_SYS_SOCKET_H
+#define _DUMMY_SYS_SOCKET_H
+
+#include <linux/socket.h>
+
+struct sockaddr {
+	__kernel_sa_family_t	sa_family;	/* address family, AF_xxx	*/
+	char			sa_data[14];	/* 14 bytes of protocol address	*/
+};
+
+#endif /* _DUMMY_SYS_SOCKET_H */
diff --git a/usr/dummy-include/sys/time.h b/usr/dummy-include/sys/time.h
new file mode 100644
index 000000000..9817b8afb
--- /dev/null
+++ b/usr/dummy-include/sys/time.h
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <linux/time.h>
diff --git a/usr/dummy-include/sys/types.h b/usr/dummy-include/sys/types.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/sys/types.h
diff --git a/usr/dummy-include/time.h b/usr/dummy-include/time.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/time.h
diff --git a/usr/dummy-include/unistd.h b/usr/dummy-include/unistd.h
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/usr/dummy-include/unistd.h