PM / devfreq: event: Add new Rockchip NoC probe driver

This patch adds NoC (Network on Chip) Probe driver which provides
the primitive values to get the performance data. For example, RK3399
has multiple NoC probes to monitor traffic statistics for analyzing
the transaction flow.

Change-Id: I66f6708f0d244488ca08f0f1f1cb36b19c7a2d0a
Signed-off-by: Finley Xiao <finley.xiao@rock-chips.com>

Documentation/devicetree/bindings/devfreq/event/rockchip-nocp.txt

@@ -0,0 +1,23 @@
+
+* Rockchip NoC (Network on Chip) Probe device
+
+The Rockchip SoCs have NoC (Network on Chip) Probe for NoC bus.
+NoC provides the primitive values to get the performance data, The
+packets that the Network on Chip (NoC) probes detects are transported
+over the network infrastructure to observer units. For example, RK3399
+has multiple NoC probes to monitor traffic statistics for analyzing the
+transaction flow.
+
+Required properties:
+- compatible: Should be one of the following.
+  - "rockchip,rk3288-nocp" - for RK3288 SoC.
+  - "rockchip,rk3368-nocp" - for RK3368 SoC.
+  - "rockchip,rk3399-nocp" - for RK3399 SoC.
+- reg: physical base address of each NoC Probe and length of memory mapped region.
+
+Example : NoC Probe nodes in Device Tree are listed below.
+
+	nocp_cci_msch0: nocp-cci-msch0@ffa86000 {
+		compatible = "rockchip,rk3399-nocp";
+		reg = <0xffa86000 0x400>;
+	};

drivers/devfreq/event/Kconfig

@@ -29,4 +29,11 @@ config DEVFREQ_EVENT_ROCKCHIP_DFI
 	  This add the devfreq-event driver for Rockchip SoC. It provides DFI
 	  (DDR Monitor Module) driver to count ddr load.
 
+config DEVFREQ_EVENT_ROCKCHIP_NOCP
+	tristate "ROCKCHIP NoC (Network On Chip) Probe DEVFREQ event Driver"
+	depends on ARCH_ROCKCHIP
+	help
+	  This add the devfreq-event driver for Rockchip SoC. It provides NoC
+	  (Network on Chip) Probe counters to monitor traffic statistics.
+
 endif # PM_DEVFREQ_EVENT

drivers/devfreq/event/Makefile

@@ -1,3 +1,4 @@
 # Exynos DEVFREQ Event Drivers
 obj-$(CONFIG_DEVFREQ_EVENT_EXYNOS_PPMU) += exynos-ppmu.o
 obj-$(CONFIG_DEVFREQ_EVENT_ROCKCHIP_DFI) += rockchip-dfi.o
+obj-$(CONFIG_DEVFREQ_EVENT_ROCKCHIP_NOCP) += rockchip-nocp.o

drivers/devfreq/event/rockchip-nocp.c

@@ -0,0 +1,166 @@
+/*
+ * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/devfreq-event.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#define EVENT_BYTE		0x08
+#define EVENT_CHAIN		0x10
+
+#define START_EN		BIT(3)
+#define GLOBAL_EN		BIT(0)
+#define START_GO		BIT(0)
+
+#define PROBE_MAINCTL		0x0008
+#define PROBE_CFGCTL		0x000c
+#define PROBE_STATPERIOD	0x0024
+#define PROBE_STATGO		0x0028
+#define PROBE_COUNTERS_0_SRC	0x0138
+#define PROBE_COUNTERS_0_VAL	0x013c
+#define PROBE_COUNTERS_1_SRC	0x014c
+#define PROBE_COUNTERS_1_VAL	0x0150
+
+struct rockchip_nocp {
+	void __iomem *reg_base;
+	struct device *dev;
+	struct devfreq_event_dev *edev;
+	struct devfreq_event_desc *desc;
+	ktime_t time;
+};
+
+static int rockchip_nocp_enable(struct devfreq_event_dev *edev)
+{
+	struct rockchip_nocp *nocp = devfreq_event_get_drvdata(edev);
+	void __iomem *reg_base = nocp->reg_base;
+
+	writel_relaxed(GLOBAL_EN, reg_base + PROBE_CFGCTL);
+	writel_relaxed(START_EN, reg_base + PROBE_MAINCTL);
+	writel_relaxed(0, reg_base + PROBE_STATPERIOD);
+	writel_relaxed(EVENT_BYTE, reg_base + PROBE_COUNTERS_0_SRC);
+	writel_relaxed(EVENT_CHAIN, reg_base + PROBE_COUNTERS_1_SRC);
+	writel_relaxed(START_GO, reg_base + PROBE_STATGO);
+
+	nocp->time = ktime_get();
+
+	return 0;
+}
+
+static int rockchip_nocp_disable(struct devfreq_event_dev *edev)
+{
+	struct rockchip_nocp *nocp = devfreq_event_get_drvdata(edev);
+	void __iomem *reg_base = nocp->reg_base;
+
+	writel_relaxed(0, reg_base + PROBE_STATGO);
+	writel_relaxed(0, reg_base + PROBE_MAINCTL);
+	writel_relaxed(0, reg_base + PROBE_CFGCTL);
+	writel_relaxed(0, reg_base + PROBE_COUNTERS_0_SRC);
+	writel_relaxed(0, reg_base + PROBE_COUNTERS_1_SRC);
+
+	return 0;
+}
+
+static int rockchip_nocp_get_event(struct devfreq_event_dev *edev,
+				   struct devfreq_event_data *edata)
+{
+	struct rockchip_nocp *nocp = devfreq_event_get_drvdata(edev);
+	void __iomem *reg_base = nocp->reg_base;
+	u32 counter = 0, counter0 = 0, counter1 = 0;
+	int time_ms = 0;
+
+	time_ms = ktime_to_ms(ktime_sub(ktime_get(), nocp->time));
+
+	counter0 = readl_relaxed(reg_base + PROBE_COUNTERS_0_VAL);
+	counter1 = readl_relaxed(reg_base + PROBE_COUNTERS_1_VAL);
+	counter = (counter0 & 0xffff) | ((counter1 & 0xffff) << 16);
+	counter = counter / 1000000;
+	if (time_ms > 0)
+		edata->load_count = (counter * 1000) / time_ms;
+
+	writel_relaxed(START_GO, reg_base + PROBE_STATGO);
+	nocp->time = ktime_get();
+
+	return 0;
+}
+
+static int rockchip_nocp_set_event(struct devfreq_event_dev *edev)
+{
+	return 0;
+}
+
+static const struct devfreq_event_ops rockchip_nocp_ops = {
+	.disable = rockchip_nocp_disable,
+	.enable = rockchip_nocp_enable,
+	.get_event = rockchip_nocp_get_event,
+	.set_event = rockchip_nocp_set_event,
+};
+
+static const struct of_device_id rockchip_nocp_id_match[] = {
+	{ .compatible = "rockchip,rk3288-nocp" },
+	{ .compatible = "rockchip,rk3368-nocp" },
+	{ .compatible = "rockchip,rk3399-nocp" },
+	{ },
+};
+
+static int rockchip_nocp_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct rockchip_nocp *nocp;
+	struct devfreq_event_desc *desc;
+	struct device_node *np = pdev->dev.of_node;
+
+	nocp = devm_kzalloc(&pdev->dev, sizeof(*nocp), GFP_KERNEL);
+	if (!nocp)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	nocp->reg_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(nocp->reg_base))
+		return PTR_ERR(nocp->reg_base);
+
+	desc = devm_kzalloc(&pdev->dev, sizeof(*desc), GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+
+	desc->ops = &rockchip_nocp_ops;
+	desc->driver_data = nocp;
+	desc->name = np->name;
+	nocp->desc = desc;
+	nocp->dev = &pdev->dev;
+	nocp->edev = devm_devfreq_event_add_edev(&pdev->dev, desc);
+	if (IS_ERR(nocp->edev)) {
+		dev_err(&pdev->dev, "failed to add devfreq-event device\n");
+		return PTR_ERR(nocp->edev);
+	}
+
+	platform_set_drvdata(pdev, nocp);
+
+	return 0;
+}
+
+static struct platform_driver rockchip_nocp_driver = {
+	.probe = rockchip_nocp_probe,
+	.driver = {
+		.name = "rockchip-nocp",
+		.of_match_table = rockchip_nocp_id_match,
+	},
+};
+module_platform_driver(rockchip_nocp_driver);
+
+MODULE_DESCRIPTION("Rockchip NoC (Network on Chip) Probe driver");
+MODULE_AUTHOR("Finley Xiao <finley.xiao@rock-chips.com>");
+MODULE_LICENSE("GPL v2");