Re: [PATCH v4 5/7] PM / devfreq: event: support rockchip dfi controller

From: hl
Date: Mon Aug 01 2016 - 04:27:51 EST


Hi Chanwoo Choi,

On 2016å08æ01æ 16:08, Chanwoo Choi wrote:
Hi Lin,

I add the one minor comment for full name of 'DRI'.

On 2016ë 08ì 01ì 16:41, Chanwoo Choi wrote:
Hi Lin,

Because you remove the 'RFC' prefix on patch title,
I think that you better to make the documentation as following:
- Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt

Regards,
Chanwoo Choi

On 2016ë 07ì 29ì 16:56, Lin Huang wrote:
on rk3399 platform, there is dfi conroller can monitor
ddr load, base on this result, we can do ddr freqency
scaling.

Signed-off-by: Lin Huang <hl@xxxxxxxxxxxxxx>
Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
---
Changes in v4:
- None

Changes in v3:
- None

Changes in v2:
- use clk_disable_unprepare and clk_enable_prepare
- remove clk_enable_prepare in probe
- remove rockchip_dfi_remove function

Changes in v1:
- None

drivers/devfreq/event/Kconfig | 7 +
drivers/devfreq/event/Makefile | 1 +
drivers/devfreq/event/rockchip-dfi.c | 253 +++++++++++++++++++++++++++++++++++
3 files changed, 261 insertions(+)
create mode 100644 drivers/devfreq/event/rockchip-dfi.c

diff --git a/drivers/devfreq/event/Kconfig b/drivers/devfreq/event/Kconfig
index a11720a..ff9279f 100644
--- a/drivers/devfreq/event/Kconfig
+++ b/drivers/devfreq/event/Kconfig
@@ -22,4 +22,11 @@ config DEVFREQ_EVENT_EXYNOS_PPMU
(Platform Performance Monitoring Unit) counters to estimate the
utilization of each module.
+config DEVFREQ_EVENT_ROCKCHIP_DFI
+ tristate "ROCKCHIP DFI DEVFREQ event Driver"
+ depends on ARCH_ROCKCHIP
+ help
+ This add the devfreq-event driver for Rockchip SoC. It provides DFI
+ (DDR Monitor Module) driver to count ddr load.
The DFI is "DDR Monitor Module" full name? I need the correct abbreviation
and full name.
We just call this module DFI in datasheet, and this module function is ddr monitor module,
yes, it is do not fit the full name, but i think it is better follow the datasheet name.

+
endif # PM_DEVFREQ_EVENT
diff --git a/drivers/devfreq/event/Makefile b/drivers/devfreq/event/Makefile
index be146ea..e3f88fc 100644
--- a/drivers/devfreq/event/Makefile
+++ b/drivers/devfreq/event/Makefile
@@ -1,2 +1,3 @@
# Exynos DEVFREQ Event Drivers
obj-$(CONFIG_DEVFREQ_EVENT_EXYNOS_PPMU) += exynos-ppmu.o
+obj-$(CONFIG_DEVFREQ_EVENT_ROCKCHIP_DFI) += rockchip-dfi.o
diff --git a/drivers/devfreq/event/rockchip-dfi.c b/drivers/devfreq/event/rockchip-dfi.c
new file mode 100644
index 0000000..96a0307
--- /dev/null
+++ b/drivers/devfreq/event/rockchip-dfi.c
@@ -0,0 +1,253 @@
+/*
+ * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
+ * Author: Lin Huang <hl@xxxxxxxxxxxxxx>
+ *
+ * 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/clk.h>
+#include <linux/devfreq-event.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/of.h>
+
+#define RK3399_DMC_NUM_CH 2
+
+/* DDRMON_CTRL */
+#define DDRMON_CTRL 0x04
+#define CLR_DDRMON_CTRL (0x1f0000 << 0)
+#define LPDDR4_EN (0x10001 << 4)
+#define HARDWARE_EN (0x10001 << 3)
+#define LPDDR3_EN (0x10001 << 2)
+#define SOFTWARE_EN (0x10001 << 1)
+#define TIME_CNT_EN (0x10001 << 0)
+
+#define DDRMON_CH0_COUNT_NUM 0x28
+#define DDRMON_CH0_DFI_ACCESS_NUM 0x2c
+#define DDRMON_CH1_COUNT_NUM 0x3c
+#define DDRMON_CH1_DFI_ACCESS_NUM 0x40
+
+/* pmu grf */
+#define PMUGRF_OS_REG2 0x308
+#define DDRTYPE_SHIFT 13
+#define DDRTYPE_MASK 7
+
+enum {
+ DDR3 = 3,
+ LPDDR3 = 6,
+ LPDDR4 = 7,
+ UNUSED = 0xFF
+};
+
+struct dmc_usage {
+ u32 access;
+ u32 total;
+};
+
+struct rockchip_dfi {
+ struct devfreq_event_dev *edev;
+ struct devfreq_event_desc *desc;
+ struct dmc_usage ch_usage[RK3399_DMC_NUM_CH];
+ struct device *dev;
+ void __iomem *regs;
+ struct regmap *regmap_pmu;
+ struct clk *clk;
+};
+
+static void rockchip_dfi_start_hardware_counter(struct devfreq_event_dev *edev)
+{
+ struct rockchip_dfi *info = devfreq_event_get_drvdata(edev);
+ void __iomem *dfi_regs = info->regs;
+ u32 val;
+ u32 ddr_type;
+
+ /* get ddr type */
+ regmap_read(info->regmap_pmu, PMUGRF_OS_REG2, &val);
+ ddr_type = (val >> DDRTYPE_SHIFT) & DDRTYPE_MASK;
+
+ /* clear DDRMON_CTRL setting */
+ writel_relaxed(CLR_DDRMON_CTRL, dfi_regs + DDRMON_CTRL);
+
+ /* set ddr type to dfi */
+ if (ddr_type == LPDDR3)
+ writel_relaxed(LPDDR3_EN, dfi_regs + DDRMON_CTRL);
+ else if (ddr_type == LPDDR4)
+ writel_relaxed(LPDDR4_EN, dfi_regs + DDRMON_CTRL);
+
+ /* enable count, use software mode */
+ writel_relaxed(SOFTWARE_EN, dfi_regs + DDRMON_CTRL);
+}
+
+static void rockchip_dfi_stop_hardware_counter(struct devfreq_event_dev *edev)
+{
+ struct rockchip_dfi *info = devfreq_event_get_drvdata(edev);
+ void __iomem *dfi_regs = info->regs;
+ u32 val;
+
+ val = readl_relaxed(dfi_regs + DDRMON_CTRL);
+ val &= ~SOFTWARE_EN;
+ writel_relaxed(val, dfi_regs + DDRMON_CTRL);
+}
+
+static int rockchip_dfi_get_busier_ch(struct devfreq_event_dev *edev)
+{
+ struct rockchip_dfi *info = devfreq_event_get_drvdata(edev);
+ u32 tmp, max = 0;
+ u32 i, busier_ch = 0;
+ void __iomem *dfi_regs = info->regs;
+
+ rockchip_dfi_stop_hardware_counter(edev);
+
+ /* Find out which channel is busier */
+ for (i = 0; i < RK3399_DMC_NUM_CH; i++) {
+ info->ch_usage[i].access = readl_relaxed(dfi_regs +
+ DDRMON_CH0_DFI_ACCESS_NUM + i * 20);
+ info->ch_usage[i].total = readl_relaxed(dfi_regs +
+ DDRMON_CH0_COUNT_NUM + i * 20);
+ tmp = info->ch_usage[i].access;
+ if (tmp > max) {
+ busier_ch = i;
+ max = tmp;
+ }
+ }
+ rockchip_dfi_start_hardware_counter(edev);
+
+ return busier_ch;
+}
+
+static int rockchip_dfi_disable(struct devfreq_event_dev *edev)
+{
+ struct rockchip_dfi *info = devfreq_event_get_drvdata(edev);
+
+ rockchip_dfi_stop_hardware_counter(edev);
+ clk_disable_unprepare(info->clk);
+
+ return 0;
+}
+
+static int rockchip_dfi_enable(struct devfreq_event_dev *edev)
+{
+ struct rockchip_dfi *info = devfreq_event_get_drvdata(edev);
+ int ret;
+
+ ret = clk_prepare_enable(info->clk);
+ if (ret) {
+ dev_err(&edev->dev, "failed to enable dfi clk: %d\n", ret);
+ return ret;
+ }
+
+ rockchip_dfi_start_hardware_counter(edev);
+ return 0;
+}
+
+static int rockchip_dfi_set_event(struct devfreq_event_dev *edev)
+{
+ return 0;
+}
+
+static int rockchip_dfi_get_event(struct devfreq_event_dev *edev,
+ struct devfreq_event_data *edata)
+{
+ struct rockchip_dfi *info = devfreq_event_get_drvdata(edev);
+ int busier_ch;
+
+ busier_ch = rockchip_dfi_get_busier_ch(edev);
+
+ edata->load_count = info->ch_usage[busier_ch].access;
+ edata->total_count = info->ch_usage[busier_ch].total;
+
+ return 0;
+}
+
+static const struct devfreq_event_ops rockchip_dfi_ops = {
+ .disable = rockchip_dfi_disable,
+ .enable = rockchip_dfi_enable,
+ .get_event = rockchip_dfi_get_event,
+ .set_event = rockchip_dfi_set_event,
+};
+
+static const struct of_device_id rockchip_dfi_id_match[] = {
+ { .compatible = "rockchip,rk3399-dfi" },
+ { },
+};
+
+static int rockchip_dfi_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rockchip_dfi *data;
+ struct resource *res;
+ struct devfreq_event_desc *desc;
+ struct device_node *np = pdev->dev.of_node, *node;
+
+ data = devm_kzalloc(dev, sizeof(struct rockchip_dfi), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ data->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(data->regs))
+ return PTR_ERR(data->regs);
+
+ data->clk = devm_clk_get(dev, "pclk_ddr_mon");
+ if (IS_ERR(data->clk)) {
+ dev_err(dev, "Cannot get the clk dmc_clk\n");
+ return PTR_ERR(data->clk);
+ };
+
+ /* try to find the optional reference to the pmu syscon */
+ node = of_parse_phandle(np, "rockchip,pmu", 0);
+ if (node) {
+ data->regmap_pmu = syscon_node_to_regmap(node);
+ if (IS_ERR(data->regmap_pmu))
+ return PTR_ERR(data->regmap_pmu);
+ }
+ data->dev = dev;
+
+ desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
+ if (!desc)
+ return -ENOMEM;
+
+ desc->ops = &rockchip_dfi_ops;
+ desc->driver_data = data;
+ desc->name = np->name;
+ data->desc = desc;
+
+ data->edev = devm_devfreq_event_add_edev(&pdev->dev, desc);
+ if (IS_ERR(data->edev)) {
+ dev_err(&pdev->dev,
+ "failed to add devfreq-event device\n");
+ return PTR_ERR(data->edev);
+ }
+
+ platform_set_drvdata(pdev, data);
+
+ return 0;
+}
+
+static struct platform_driver rockchip_dfi_driver = {
+ .probe = rockchip_dfi_probe,
+ .driver = {
+ .name = "rockchip-dfi",
+ .of_match_table = rockchip_dfi_id_match,
+ },
+};
+module_platform_driver(rockchip_dfi_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Lin Huang <hl@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Rockchip dfi driver");
s/dfi -> DFI

Regards,
Chanwoo Choi


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--
Lin Huang