Raspberry Pi support for AXI bus events in Linux perf tool

Documentation/devicetree/bindings/perf/brcm,bcm2835-axiperf.yaml

@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/perf/brcm,bcm2835-axiperf.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom BCM2835/2711/2712 AXI Performance Monitor
+
+maintainers:
+  - Ian Rogers <irogers@google.com>
+
+description: |
+  The Broadcom BCM2835 series (including BCM2711 and BCM2712) features hardware
+  performance monitors on the AXI bus for evaluating memory bandwidth and
+  system traffic. Depending on the SoC architecture, multiple monitors exist.
+  The primary
+  monitor evaluates the System fabric, while the secondary monitor evaluates the
+  VideoCore VPU hardware.
+
+  Older silicon generally restricts direct MMIO access to the VPU endpoints,
+  requiring them to be accessed over the Raspberry Pi firmware mailbox
+  interface. If the VPU endpoints are memory-mapped, they are supplied as
+  secondary resources.
+
+properties:
+  compatible:
+    enum:
+      - brcm,bcm2835-axiperf
+      - brcm,bcm2711-axiperf
+      - brcm,bcm2712-axiperf
+
+  reg:
+    minItems: 1
+    maxItems: 2
+    description: |
+      Memory-mapped I/O resource regions for the AXI PMU endpoints.
+      Typically ordered as System monitor, followed by VPU monitor if directly
+      mapped.
+
+  firmware:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: |
+      Phandle to the Raspberry Pi firmware node. Required on older silicon
+      (BCM2835-BCM2711) where VideoCore VPU endpoints are exclusively accessed
+      via firmware mailbox IPC.
+
+required:
+  - compatible
+  - reg
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - brcm,bcm2835-axiperf
+              - brcm,bcm2711-axiperf
+    then:
+      required:
+        - firmware
+
+additionalProperties: false
+
+examples:
+  - |
+    pmu@7e00a000 {
+        compatible = "brcm,bcm2835-axiperf";
+        reg = <0x7e00a000 0x100>;
+        firmware = <&firmware>;
+    };
+  - |
+    pmu@7d620000 {
+        compatible = "brcm,bcm2712-axiperf";
+        reg = <0x7d620000 0x100>,
+              <0x7d630000 0x100>;
+    };

drivers/perf/Kconfig

@@ -279,6 +279,15 @@
           Say y if you want to use Raspberry Pi AXI performance monitors, m if
           you want to build it as a module.
 
+config RPI_AXI_PMU
+	tristate "Raspberry Pi AXI PMU support"
+	depends on ARCH_BRCMSTB || RASPBERRYPI_FIRMWARE || (COMPILE_TEST && !RASPBERRYPI_FIRMWARE)
+	help
+	  Support for the perf AXI Performance Monitoring Unit (PMU) found on Broadcom
+	  SoCs used in Raspberry Pi platforms (BCM2835, BCM2836, BCM2837, BCM2711, BCM2712).
+
+	  If compiled as a module, it will be called rpi_axi_pmu.
+
 source "drivers/perf/hisilicon/Kconfig"
 
 config MARVELL_CN10K_DDR_PMU

drivers/perf/Makefile

@@ -36,3 +36,4 @@ obj-$(CONFIG_ARM_CORESIGHT_PMU_ARCH_SYSTEM_PMU) += arm_cspmu/
 obj-$(CONFIG_MESON_DDR_PMU) += amlogic/
 obj-$(CONFIG_CXL_PMU) += cxl_pmu.o
 obj-$(CONFIG_RPI_AXIPERF) += raspberrypi_axi_monitor.o
+obj-$(CONFIG_RPI_AXI_PMU) += rpi_axi_pmu.o