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, 129 insertions, 0 deletions

diff --git a/include/trace/events/pci.h b/include/trace/events/pci.h
new file mode 100644
index 000000000..9a9122f62
--- /dev/null
+++ b/include/trace/events/pci.h
@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM pci
+
+#if !defined(_TRACE_HW_EVENT_PCI_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_HW_EVENT_PCI_H
+
+#include <uapi/linux/pci_regs.h>
+#include <linux/tracepoint.h>
+
+#define PCI_HOTPLUG_EVENT						\
+	EM(PCI_HOTPLUG_LINK_UP,			"LINK_UP")		\
+	EM(PCI_HOTPLUG_LINK_DOWN,		"LINK_DOWN")		\
+	EM(PCI_HOTPLUG_CARD_PRESENT,		"CARD_PRESENT")		\
+	EMe(PCI_HOTPLUG_CARD_NOT_PRESENT,	"CARD_NOT_PRESENT")
+
+/* Enums require being exported to userspace, for user tool parsing */
+#undef EM
+#undef EMe
+#define EM(a, b)	TRACE_DEFINE_ENUM(a);
+#define EMe(a, b)	TRACE_DEFINE_ENUM(a);
+
+PCI_HOTPLUG_EVENT
+
+/*
+ * Now redefine the EM() and EMe() macros to map the enums to the strings
+ * that will be printed in the output.
+ */
+#undef EM
+#undef EMe
+#define EM(a, b)	{a, b},
+#define EMe(a, b)	{a, b}
+
+/*
+ * Note: For generic PCI hotplug events, we pass already-resolved strings
+ * (port_name, slot) instead of driver-specific structures like 'struct
+ * controller'.  This is because different PCI hotplug drivers (pciehp, cpqphp,
+ * ibmphp, shpchp) define their own versions of 'struct controller' with
+ * different fields and helper functions. Using driver-specific structures would
+ * make the tracepoint interface non-generic and cause compatibility issues
+ * across different drivers.
+ */
+TRACE_EVENT(pci_hp_event,
+
+	TP_PROTO(const char *port_name,
+		 const char *slot,
+		 const int event),
+
+	TP_ARGS(port_name, slot, event),
+
+	TP_STRUCT__entry(
+		__string(	port_name,	port_name	)
+		__string(	slot,		slot		)
+		__field(	int,		event	)
+	),
+
+	TP_fast_assign(
+		__assign_str(port_name);
+		__assign_str(slot);
+		__entry->event = event;
+	),
+
+	TP_printk("%s slot:%s, event:%s\n",
+		__get_str(port_name),
+		__get_str(slot),
+		__print_symbolic(__entry->event, PCI_HOTPLUG_EVENT)
+	)
+);
+
+#define PCI_EXP_LNKSTA_LINK_STATUS_MASK (PCI_EXP_LNKSTA_LBMS | \
+					 PCI_EXP_LNKSTA_LABS | \
+					 PCI_EXP_LNKSTA_LT | \
+					 PCI_EXP_LNKSTA_DLLLA)
+
+#define LNKSTA_FLAGS					\
+	{ PCI_EXP_LNKSTA_LT,	"LT"},			\
+	{ PCI_EXP_LNKSTA_DLLLA,	"DLLLA"},		\
+	{ PCI_EXP_LNKSTA_LBMS,	"LBMS"},		\
+	{ PCI_EXP_LNKSTA_LABS,	"LABS"}
+
+TRACE_EVENT(pcie_link_event,
+
+	TP_PROTO(struct pci_bus *bus,
+		  unsigned int reason,
+		  unsigned int width,
+		  unsigned int status
+		),
+
+	TP_ARGS(bus, reason, width, status),
+
+	TP_STRUCT__entry(
+		__string(	port_name,	pci_name(bus->self))
+		__field(	unsigned int,	type		)
+		__field(	unsigned int,	reason		)
+		__field(	unsigned int,	cur_bus_speed	)
+		__field(	unsigned int,	max_bus_speed	)
+		__field(	unsigned int,	width		)
+		__field(	unsigned int,	flit_mode	)
+		__field(	unsigned int,	link_status	)
+	),
+
+	TP_fast_assign(
+		__assign_str(port_name);
+		__entry->type			= pci_pcie_type(bus->self);
+		__entry->reason			= reason;
+		__entry->cur_bus_speed		= bus->cur_bus_speed;
+		__entry->max_bus_speed		= bus->max_bus_speed;
+		__entry->width			= width;
+		__entry->flit_mode		= bus->flit_mode;
+		__entry->link_status		= status;
+	),
+
+	TP_printk("%s type:%d, reason:%d, cur_bus_speed:%d, max_bus_speed:%d, width:%u, flit_mode:%u, status:%s\n",
+		__get_str(port_name),
+		__entry->type,
+		__entry->reason,
+		__entry->cur_bus_speed,
+		__entry->max_bus_speed,
+		__entry->width,
+		__entry->flit_mode,
+		__print_flags((unsigned long)__entry->link_status, "|",
+				LNKSTA_FLAGS)
+	)
+);
+
+#endif /* _TRACE_HW_EVENT_PCI_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>