drm/tegra: dc: Trace register accesses

Add tracepoint events for display controller register accesses.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/Makefile

@@ -17,4 +17,6 @@ tegra-drm-y := \
 	falcon.o \
 	vic.o
 
+tegra-drm-y += trace.o
+
 obj-$(CONFIG_DRM_TEGRA) += tegra-drm.o

drivers/gpu/drm/tegra/drm.h

@@ -23,6 +23,7 @@
 #include <drm/drm_fixed.h>
 
 #include "gem.h"
+#include "trace.h"
 
 struct reset_control;
 
@@ -174,12 +175,17 @@ static inline struct tegra_dc *to_tegra_dc(struct drm_crtc *crtc)
 static inline void tegra_dc_writel(struct tegra_dc *dc, u32 value,
 				   unsigned int offset)
 {
+	trace_dc_writel(dc->dev, offset, value);
 	writel(value, dc->regs + (offset << 2));
 }
 
 static inline u32 tegra_dc_readl(struct tegra_dc *dc, unsigned int offset)
 {
-	return readl(dc->regs + (offset << 2));
+	u32 value = readl(dc->regs + (offset << 2));
+
+	trace_dc_readl(dc->dev, offset, value);
+
+	return value;
 }
 
 struct tegra_dc_window {

drivers/gpu/drm/tegra/trace.c

+#define CREATE_TRACE_POINTS
+#include "trace.h"

drivers/gpu/drm/tegra/trace.h

+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM tegra
+
+#if !defined(DRM_TEGRA_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define DRM_TEGRA_TRACE_H 1
+
+#include <linux/device.h>
+#include <linux/tracepoint.h>
+
+DECLARE_EVENT_CLASS(register_access,
+	TP_PROTO(struct device *dev, unsigned int offset, u32 value),
+	TP_ARGS(dev, offset, value),
+	TP_STRUCT__entry(
+		__field(struct device *, dev)
+		__field(unsigned int, offset)
+		__field(u32, value)
+	),
+	TP_fast_assign(
+		__entry->dev = dev;
+		__entry->offset = offset;
+		__entry->value = value;
+	),
+	TP_printk("%s %04x %08x", dev_name(__entry->dev), __entry->offset,
+		  __entry->value)
+);
+
+DEFINE_EVENT(register_access, dc_writel,
+	TP_PROTO(struct device *dev, unsigned int offset, u32 value),
+	TP_ARGS(dev, offset, value));
+DEFINE_EVENT(register_access, dc_readl,
+	TP_PROTO(struct device *dev, unsigned int offset, u32 value),
+	TP_ARGS(dev, offset, value));
+
+#endif /* DRM_TEGRA_TRACE_H */
+
+/* This part must be outside protection */
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE trace
+#include <trace/define_trace.h>