[RFC PATCHv2 4/7] devfreq: event: Add exynos-ppmu devfreq event driver

From: Chanwoo Choi
Date: Tue Dec 09 2014 - 09:16:48 EST


This patch add exynos-ppmu devfreq event driver to provider raw data about
the utilization of each IP in Exynos SoC series.

Cc: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
Cc: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
---
drivers/devfreq/Kconfig | 9 +
drivers/devfreq/event/Makefile | 1 +
drivers/devfreq/event/exynos-ppmu.c | 409 ++++++++++++++++++++++++++++++++++++
3 files changed, 419 insertions(+)
create mode 100644 drivers/devfreq/event/exynos-ppmu.c

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 4d15b62..d4559f7 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -89,4 +89,13 @@ config ARM_EXYNOS5_BUS_DEVFREQ

comment "DEVFREQ Event Drivers"

+config DEVFREQ_EVENT_EXYNOS_PPMU
+ bool "EXYNOS PPMU (Performance Profiling Monitoring Unit) DEVFREQ event Driver"
+ depends on ARCH_EXYNOS
+ select PM_OPP
+ help
+ This add the DEVFREQ event driver for Exynos SoC. It provides PPMU
+ (Performance Profiling Monitoring Unit) counters to estimate the
+ utilization of each module.
+
endif # PM_DEVFREQ
diff --git a/drivers/devfreq/event/Makefile b/drivers/devfreq/event/Makefile
index dc56005..be146ea 100644
--- a/drivers/devfreq/event/Makefile
+++ b/drivers/devfreq/event/Makefile
@@ -1 +1,2 @@
# Exynos DEVFREQ Event Drivers
+obj-$(CONFIG_DEVFREQ_EVENT_EXYNOS_PPMU) += exynos-ppmu.o
diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
new file mode 100644
index 0000000..2706f23
--- /dev/null
+++ b/drivers/devfreq/event/exynos-ppmu.c
@@ -0,0 +1,409 @@
+/*
+ * exynos_ppmu.c - EXYNOS PPMU (Performance Profiling Monitoring Units) support
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Author : Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This driver is based on drivers/devfreq/exynos/exynos_ppmu.c
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/suspend.h>
+#include <linux/devfreq.h>
+
+#define PPMU_ENABLE BIT(0)
+#define PPMU_DISABLE 0x0
+#define PPMU_CYCLE_RESET BIT(1)
+#define PPMU_COUNTER_RESET BIT(2)
+
+#define PPMU_ENABLE_COUNT0 BIT(0)
+#define PPMU_ENABLE_COUNT1 BIT(1)
+#define PPMU_ENABLE_COUNT2 BIT(2)
+#define PPMU_ENABLE_COUNT3 BIT(3)
+#define PPMU_ENABLE_CYCLE BIT(31)
+
+#define PPMU_CNTENS 0x10
+#define PPMU_FLAG 0x50
+#define PPMU_CCNT_OVERFLOW BIT(31)
+#define PPMU_CCNT 0x100
+
+#define PPMU_PMCNT0 0x110
+#define PPMU_PMCNT_OFFSET 0x10
+#define PMCNT_OFFSET(x) (PPMU_PMCNT0 + (PPMU_PMCNT_OFFSET * x))
+
+#define PPMU_BEVT0SEL 0x1000
+#define PPMU_BEVTSEL_OFFSET 0x100
+#define PPMU_BEVTSEL(x) (PPMU_BEVT0SEL + (x * PPMU_BEVTSEL_OFFSET))
+
+#define RD_DATA_COUNT 0x5
+#define WR_DATA_COUNT 0x6
+#define RDWR_DATA_COUNT 0x7
+
+enum ppmu_counter {
+ PPMU_PMNCNT0,
+ PPMU_PMNCNT1,
+ PPMU_PMNCNT2,
+ PPMU_PMNCNT3,
+ PPMU_PMNCNT_MAX,
+};
+
+/* Platform data */
+struct exynos_ppmu_data {
+ struct devfreq *devfreq;
+ struct devfreq_event_dev **event_dev;
+ struct devfreq_event_desc *desc;
+ unsigned int num_events;
+
+ struct device *dev;
+ struct clk *clk_ppmu;
+ struct mutex lock;
+
+ struct __exynos_ppmu {
+ void __iomem *hw_base;
+ unsigned int ccnt;
+ unsigned int event[PPMU_PMNCNT_MAX];
+ unsigned int count[PPMU_PMNCNT_MAX];
+ unsigned long long ns;
+ ktime_t reset_time;
+ bool ccnt_overflow;
+ bool count_overflow[PPMU_PMNCNT_MAX];
+ } ppmu;
+};
+
+struct __exynos_ppmu_events {
+ char *name;
+ int id;
+} ppmu_events[] = {
+ { "ppmu-dmc0-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-dmc0-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-dmc0-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-dmc0-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-dmc1-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-dmc1-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-dmc1-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-dmc1-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-cpu-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-cpu-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-cpu-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-cpu-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-rightbus-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-rightbus-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-rightbus-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-rightbus-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-leftbus-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-leftbus-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-leftbus-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-leftbus-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-camif-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-camif-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-camif-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-camif-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-lcd0-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-lcd0-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-lcd0-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-lcd0-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-g3d-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-g3d-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-g3d-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-g3d-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-mfc-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-mfc-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-mfc-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-mfc-pmcnt3", PPMU_PMNCNT3 },
+
+ { "ppmu-fsys-pmcnt0", PPMU_PMNCNT0 },
+ { "ppmu-fsys-pmcnt1", PPMU_PMNCNT1 },
+ { "ppmu-fsys-pmcnt2", PPMU_PMNCNT2 },
+ { "ppmu-fsys-pmcnt3", PPMU_PMNCNT3 },
+ { /* sentinel */ },
+};
+
+static int exynos_ppmu_enable(struct devfreq_event_dev *event_dev)
+{
+ struct exynos_ppmu_data *exynos_ppmu = event_dev_get_drvdata(event_dev);
+
+ __raw_writel(PPMU_ENABLE, exynos_ppmu->ppmu.hw_base);
+
+ return 0;
+}
+
+static int exynos_ppmu_disable(struct devfreq_event_dev *event_dev)
+{
+ struct exynos_ppmu_data *exynos_ppmu = event_dev_get_drvdata(event_dev);
+
+ __raw_writel(PPMU_DISABLE, exynos_ppmu->ppmu.hw_base);
+
+ return 0;
+}
+
+static bool exynos_ppmu_is_enabled(struct devfreq_event_dev *event_dev)
+{
+ struct exynos_ppmu_data *exynos_ppmu = event_dev_get_drvdata(event_dev);
+ int val;
+
+ val = __raw_readl(exynos_ppmu->ppmu.hw_base);
+ if (val & PPMU_ENABLE)
+ return true;
+
+ return false;
+}
+
+static int exynos_ppmu_find_ppmu_id(struct devfreq_event_dev *event_dev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ppmu_events); i++)
+ if (!strcmp(event_dev->desc->name, ppmu_events[i].name))
+ return ppmu_events[i].id;
+
+ return -EINVAL;
+}
+
+static int exynos_ppmu_set_event(struct devfreq_event_dev *event_dev,
+ enum devfreq_event_type event_type)
+{
+ struct exynos_ppmu_data *exynos_ppmu = event_dev_get_drvdata(event_dev);
+ void __iomem *ppmu_base = exynos_ppmu->ppmu.hw_base;
+ int id = exynos_ppmu_find_ppmu_id(event_dev);
+
+ __raw_writel(RDWR_DATA_COUNT, ppmu_base + PPMU_BEVTSEL(id));
+
+ return 0;
+}
+
+static int exynos_ppmu_get_event(struct devfreq_event_dev *event_dev,
+ enum devfreq_event_type event_type,
+ int *total_event)
+{
+ struct exynos_ppmu_data *exynos_ppmu = event_dev_get_drvdata(event_dev);
+ void __iomem *ppmu_base = exynos_ppmu->ppmu.hw_base;
+ int id = exynos_ppmu_find_ppmu_id(event_dev);
+ int cnt, total_cnt;
+
+ total_cnt = __raw_readl(ppmu_base + PPMU_CCNT);
+
+ if (id == PPMU_PMNCNT3)
+ cnt = ((__raw_readl(ppmu_base + PMCNT_OFFSET(id)) << 8) |
+ __raw_readl(ppmu_base + PMCNT_OFFSET(id + 1)));
+ else
+ cnt = __raw_readl(ppmu_base + PMCNT_OFFSET(id));
+
+ *total_event = total_cnt;
+
+ return cnt;
+}
+
+static int exynos_ppmu_reset(struct devfreq_event_dev *event_dev)
+{
+ struct exynos_ppmu_data *exynos_ppmu = event_dev_get_drvdata(event_dev);
+ void __iomem *ppmu_base = exynos_ppmu->ppmu.hw_base;
+
+ __raw_writel(PPMU_CYCLE_RESET | PPMU_COUNTER_RESET, ppmu_base);
+ __raw_writel(PPMU_ENABLE_CYCLE |
+ PPMU_ENABLE_COUNT0 |
+ PPMU_ENABLE_COUNT1 |
+ PPMU_ENABLE_COUNT2 |
+ PPMU_ENABLE_COUNT3,
+ ppmu_base + PPMU_CNTENS);
+ __raw_writel(PPMU_ENABLE, exynos_ppmu->ppmu.hw_base);
+
+ return 0;
+}
+
+static struct devfreq_event_ops exynos_ppmu_ops = {
+ .enable = exynos_ppmu_enable,
+ .disable = exynos_ppmu_disable,
+ .is_enabled = exynos_ppmu_is_enabled,
+ .set_event = exynos_ppmu_set_event,
+ .get_event = exynos_ppmu_get_event,
+ .reset = exynos_ppmu_reset,
+};
+
+static int of_get_devfreq_events(struct device_node *np,
+ struct exynos_ppmu_data *exynos_ppmu)
+{
+ struct devfreq_event_desc *desc;
+ struct device *dev = exynos_ppmu->dev;
+ struct device_node *events_np, *node;
+ int i, j, count;
+
+ events_np = of_find_node_by_name(np, "events");
+ if (!events_np) {
+ dev_err(dev, "Failed to find ppmus sub-node\n");
+ return -EINVAL;
+ }
+
+ count = of_get_child_count(events_np);
+ desc = devm_kzalloc(dev, sizeof(struct devfreq_event_desc) * count,
+ GFP_KERNEL);
+ if (!desc)
+ return -ENOMEM;
+ exynos_ppmu->num_events = count;
+
+ j = 0;
+ for_each_child_of_node(events_np, node) {
+ for (i = 0; i < ARRAY_SIZE(ppmu_events); i++) {
+ if (!of_node_cmp(node->name, ppmu_events[i].name))
+ break;
+ }
+
+ if (i == ARRAY_SIZE(ppmu_events)) {
+ dev_warn(dev,
+ "don't know how to configure events : %s\n",
+ node->name);
+ continue;
+ }
+ desc[j].ops = &exynos_ppmu_ops;
+ desc[j].driver_data = exynos_ppmu;
+ desc[j].event_type |= DEVFREQ_EVENT_TYPE_RAW_DATA;
+ of_property_read_string(node, "event-name", &desc[j].name);
+ j++;
+ }
+ exynos_ppmu->desc = desc;
+
+ return 0;
+}
+
+static int exynos_ppmu_parse_dt(struct exynos_ppmu_data *exynos_ppmu)
+{
+ struct device *dev = exynos_ppmu->dev;
+ struct device_node *np = dev->of_node;
+ int ret = 0;
+
+ if (!np) {
+ dev_err(dev, "Failed to find devicetree node\n");
+ return -EINVAL;
+ }
+
+ /* Maps the memory mapped IO to control PPMU register */
+ exynos_ppmu->ppmu.hw_base = of_iomap(np, 0);
+ if (IS_ERR_OR_NULL(exynos_ppmu->ppmu.hw_base)) {
+ dev_err(dev, "Failed to map memory region\n");
+ ret = -EINVAL;
+ goto err_iomap;
+ }
+
+ /* FIXME: Get the clock of ppmu and enable this clock */
+ exynos_ppmu->clk_ppmu = devm_clk_get(dev, "ppmu");
+ if (IS_ERR(exynos_ppmu->clk_ppmu))
+ dev_warn(dev, "Failed to get PPMU clock\n");
+
+ ret = of_get_devfreq_events(np, exynos_ppmu);
+ if (ret < 0) {
+ dev_err(dev, "Failed to parse exynos ppmu dt node\n");
+ goto err_clock;
+ }
+
+ return 0;
+
+err_clock:
+ clk_disable_unprepare(exynos_ppmu->clk_ppmu);
+err_iomap:
+ iounmap(exynos_ppmu->ppmu.hw_base);
+
+ return ret;
+}
+
+static int exynos_ppmu_probe(struct platform_device *pdev)
+{
+ struct exynos_ppmu_data *exynos_ppmu;
+ struct devfreq_event_dev **event_dev;
+ struct devfreq_event_desc *desc;
+ int i, ret = 0, size;
+
+ /* Allocate the memory of exynos_ppmu_data and initialize it */
+ exynos_ppmu = devm_kzalloc(&pdev->dev, sizeof(struct exynos_ppmu_data),
+ GFP_KERNEL);
+ if (!exynos_ppmu)
+ return -ENOMEM;
+
+ mutex_init(&exynos_ppmu->lock);
+ exynos_ppmu->dev = &pdev->dev;
+
+ /* Parse dt data to get resource */
+ ret = exynos_ppmu_parse_dt(exynos_ppmu);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to parse DT node for resource\n");
+ return ret;
+ }
+ desc = exynos_ppmu->desc;
+
+ size = sizeof(struct devfreq_event_dev *) * exynos_ppmu->num_events;
+ exynos_ppmu->event_dev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
+ if (!exynos_ppmu->event_dev) {
+ dev_err(&pdev->dev,
+ "Failed to allocate memory devfreq_event_dev list\n");
+ return -ENOMEM;
+ }
+ event_dev = exynos_ppmu->event_dev;
+ platform_set_drvdata(pdev, exynos_ppmu);
+
+ for (i = 0; i < exynos_ppmu->num_events; i++) {
+ event_dev[i] = devfreq_add_event_device(&pdev->dev, &desc[i]);
+ if (IS_ERR(event_dev)) {
+ ret = PTR_ERR(event_dev);
+ dev_err(&pdev->dev, "Failed to add devfreq evt dev\n");
+ goto err;
+ }
+ }
+
+ return 0;
+err:
+ clk_disable_unprepare(exynos_ppmu->clk_ppmu);
+ iounmap(exynos_ppmu->ppmu.hw_base);
+
+ return ret;
+}
+
+static int exynos_ppmu_remove(struct platform_device *pdev)
+{
+ struct exynos_ppmu_data *exynos_ppmu = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(exynos_ppmu->clk_ppmu);
+ iounmap(exynos_ppmu->ppmu.hw_base);
+
+ /* Remove devfreq instance */
+ devfreq_remove_device(exynos_ppmu->devfreq);
+
+ return 0;
+}
+
+static struct of_device_id exynos_ppmu_id_match[] = {
+ { .compatible = "samsung,exynos-ppmu", },
+ { /* sentinel */ },
+};
+
+static struct platform_driver exynos_ppmu_driver = {
+ .probe = exynos_ppmu_probe,
+ .remove = exynos_ppmu_remove,
+ .driver = {
+ .name = "exynos-ppmu",
+ .owner = THIS_MODULE,
+ .of_match_table = exynos_ppmu_id_match,
+ },
+};
+
+module_platform_driver(exynos_ppmu_driver);
+
+MODULE_DESCRIPTION("EXYNOS PPMU(Performance Profiling Monitoring Unit) driver");
+MODULE_AUTHOR("Chanwoo Choi <cw00.choi@xxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:exynos-ppmu");
--
1.8.5.5

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