Historically there is no common trace event for GPU frequency, in
downstream Android each different hardware vendor implements their own
way to expose GPU frequency, for example as a debugfs node. This patch
standardize it as a common trace event in upstream linux kernel to help
the ecosystem have a common implementation across hardware vendors.
Toolings in the Linux ecosystem will benefit from this especially in the
downstream Android, where this information is critical to graphics
developers.
Signed-off-by: Peiyong Lin <l...@google.com>
---
Changelog since v3:
- Correct copyright title.
Changelog since v2:
- Add more comments to indicate when the event should be emitted.
- Change state to frequency.
Changelog since v1:
- Use %u in TP_printk
drivers/gpu/Makefile | 1 +
drivers/gpu/trace/Kconfig | 3 +++
drivers/gpu/trace/Makefile | 1 +
drivers/gpu/trace/trace_gpu_frequency.c | 13 ++++++++++
include/trace/events/power.h | 33 +++++++++++++++++++++++++
5 files changed, 51 insertions(+)
create mode 100644 drivers/gpu/trace/trace_gpu_frequency.c
diff --git a/drivers/gpu/Makefile b/drivers/gpu/Makefile
index 835c88318cec..f289a47eb031 100644
--- a/drivers/gpu/Makefile
+++ b/drivers/gpu/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_TEGRA_HOST1X) += host1x/
obj-y += drm/ vga/
obj-$(CONFIG_IMX_IPUV3_CORE) += ipu-v3/
obj-$(CONFIG_TRACE_GPU_MEM) += trace/
+obj-$(CONFIG_TRACE_GPU_FREQUENCY) += trace/
diff --git a/drivers/gpu/trace/Kconfig b/drivers/gpu/trace/Kconfig
index c24e9edd022e..ac4aec8d5845 100644
--- a/drivers/gpu/trace/Kconfig
+++ b/drivers/gpu/trace/Kconfig
@@ -2,3 +2,6 @@
config TRACE_GPU_MEM
bool
+
+config TRACE_GPU_FREQUENCY
+ bool
diff --git a/drivers/gpu/trace/Makefile b/drivers/gpu/trace/Makefile
index b70fbdc5847f..2b7ae69327d6 100644
--- a/drivers/gpu/trace/Makefile
+++ b/drivers/gpu/trace/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_TRACE_GPU_MEM) += trace_gpu_mem.o
+obj-$(CONFIG_TRACE_GPU_FREQUENCY) += trace_gpu_frequency.o
diff --git a/drivers/gpu/trace/trace_gpu_frequency.c
b/drivers/gpu/trace/trace_gpu_frequency.c
new file mode 100644
index 000000000000..668fabd6b77a
--- /dev/null
+++ b/drivers/gpu/trace/trace_gpu_frequency.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * GPU frequency trace points
+ *
+ * Copyright (C) 2020 Google LLC
+ */
+
+#include <linux/module.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/power.h>
+
+EXPORT_TRACEPOINT_SYMBOL(gpu_frequency);
diff --git a/include/trace/events/power.h b/include/trace/events/power.h
index af5018aa9517..343825a76953 100644
--- a/include/trace/events/power.h
+++ b/include/trace/events/power.h
@@ -500,6 +500,39 @@ DEFINE_EVENT(dev_pm_qos_request, dev_pm_qos_remove_request,
TP_ARGS(name, type, new_value)
);
+
+/**
+ * gpu_frequency - Reports the GPU frequency in GPU clock domains.
+ *
+ * This event should be emitted whenever there's a GPU frequency change
happens,
+ * or a GPU goes from idle state to active state, or vice versa.
+ *
+ * When the GPU goes from idle state to active state, this event should report
+ * the GPU frequency of the active state. When the GPU goes from active state
to
+ * idle state, this event should report a zero frequency value.
+ *
+ * @frequency: New frequency (in KHz)
+ * @gpu_id: Id for each GPU clock domain
+ */
+TRACE_EVENT(gpu_frequency,
+
+ TP_PROTO(unsigned int frequency, unsigned int gpu_id),
+
+ TP_ARGS(frequency, gpu_id),
+
+ TP_STRUCT__entry(
+ __field(unsigned int, frequency)
+ __field(unsigned int, gpu_id)
+ ),
+
+ TP_fast_assign(
+ __entry->frequency = frequency;
+ __entry->gpu_id = gpu_id;
+ ),
+
+ TP_printk("frequency=%u gpu_id=%u",
+ __entry->frequency, __entry->gpu_id)
+);
#endif /* _TRACE_POWER_H */
/* This part must be outside protection */
--
2.29.0.rc1.297.gfa9743e501-goog
