perf/amlogic: Add support for Amlogic meson G12 SoC DDR PMU driver

This patch adds support Amlogic meson G12 series SoC
DDR bandwidth PMU driver framework and interfaces.

The PMU not only can monitor the total DDR bandwidth,
but also the bandwidth which is from individual IP module.

Example usage:

 $ perf stat -a -e aml_ddr_bw/total_rw_bytes/ -I 1000 sleep 10

- or -

 $ perf stat -a -e \
   aml_ddr_bw/total_rw_bytes/,\
   aml_ddr_bw/chan_1_rw_bytes,arm=1/ -I 1000 \
   sleep 10

g12 SoC support 4 channels to monitor DDR bandwidth
simultaneously. Each channel can monitor up to 4 IP modules
simultaneously.

For Instance, If you want to get the sum of DDR bandwidth
from CPU, GPU, USB3.0 and VDEC. You can use the following
command parameters to display.

 $ perf stat -a -e \
   aml_ddr_bw/chan_2_rw_bytes,arm=1,gpu=1,usb3_0=1,nna=1/ -I 1000 \
   sleep 10

Other events are supported, and advertised via perf list.

Signed-off-by: Jiucheng Xu <jiucheng.xu@amlogic.com>

MAINTAINERS

@@ -1050,6 +1050,13 @@ S:	Maintained
 F:	Documentation/hid/amd-sfh*
 F:	drivers/hid/amd-sfh-hid/
 
+AMLOGIC DDR PMU DRIVER
+M:	Jiucheng Xu <jiucheng.xu@amlogic.com>
+S:	Supported
+W:	http://www.amlogic.com
+F:	drivers/perf/amlogic/
+F:	include/soc/amlogic/
+
 AMPHION VPU CODEC V4L2 DRIVER
 M:	Ming Qian <ming.qian@nxp.com>
 M:	Shijie Qin <shijie.qin@nxp.com>

drivers/perf/Kconfig

@@ -192,4 +192,6 @@ config MARVELL_CN10K_DDR_PMU
 	  Enable perf support for Marvell DDR Performance monitoring
 	  event on CN10K platform.
 
+source "drivers/perf/amlogic/Kconfig"
+
 endmenu

drivers/perf/Makefile

@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_AML_DDR_PMU) += amlogic/
 obj-$(CONFIG_ARM_CCI_PMU) += arm-cci.o
 obj-$(CONFIG_ARM_CCN) += arm-ccn.o
 obj-$(CONFIG_ARM_CMN) += arm-cmn.o

drivers/perf/amlogic/Kconfig

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config AML_DDR_PMU
+	tristate "Amlogic DDR Bandwidth Performance Monitor"
+	depends on ARCH_MESON || COMPILE_TEST
+	help
+          Provides support for the DDR performance monitor
+          in Amlogic SoCs, which can give information about
+          memory throughput and other related events. It
+          supports multiple channels to monitor the memory
+          bandwidth simultaneously.

drivers/perf/amlogic/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_AML_DDR_PMU) += aml_ddr_pmu.o
+
+aml_ddr_pmu-y	:= aml_ddr_pmu_core.o aml_ddr_pmu_g12.o