hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tu…

…ne and Trace device

HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
Endpoint(RCiEP) device, providing the capability to dynamically monitor and
tune the PCIe traffic and trace the TLP headers.

Add the driver for the device to enable the trace function. Register PMU
device of PTT trace, then users can use trace through perf command. The
driver makes use of perf AUX trace function and support the following
events to configure the trace:

- filter: select Root port or Endpoint to trace
- type: select the type of traced TLP headers
- direction: select the direction of traced TLP headers
- format: select the data format of the traced TLP headers

This patch initially add basic trace support of PTT device.

Acked-by: Mathieu Poirier <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Reviewed-by: John Garry <[email protected]>
Signed-off-by: Yicong Yang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mathieu Poirier <[email protected]>

drivers/Makefile

@@ -175,6 +175,7 @@ obj-$(CONFIG_USB4)		+= thunderbolt/
 obj-$(CONFIG_CORESIGHT)		+= hwtracing/coresight/
 obj-y				+= hwtracing/intel_th/
 obj-$(CONFIG_STM)		+= hwtracing/stm/
+obj-$(CONFIG_HISI_PTT)		+= hwtracing/ptt/
 obj-y				+= android/
 obj-$(CONFIG_NVMEM)		+= nvmem/
 obj-$(CONFIG_FPGA)		+= fpga/

drivers/hwtracing/Kconfig

@@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
 
 source "drivers/hwtracing/intel_th/Kconfig"
 
+source "drivers/hwtracing/ptt/Kconfig"
+
 endmenu

drivers/hwtracing/ptt/Kconfig

@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config HISI_PTT
+	tristate "HiSilicon PCIe Tune and Trace Device"
+	depends on ARM64 || (COMPILE_TEST && 64BIT)
+	depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
+	help
+	  HiSilicon PCIe Tune and Trace device exists as a PCIe RCiEP
+	  device, and it provides support for PCIe traffic tuning and
+	  tracing TLP headers to the memory.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called hisi_ptt.

drivers/hwtracing/ptt/Makefile

@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_HISI_PTT) += hisi_ptt.o