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

From: [email-masked] (hl)
Date: Mon, 1 Aug 2016 16:27:05 +0800

Hi Chanwoo Choi,

On 2016?08?01? 16:08, Chanwoo Choi wrote:
> Hi Lin,
>
> I add the one minor comment for full name of 'DRI'.
>
> On 2016? 08? 01? 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 2016? 07? 29? 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 <[email-masked]>
>>> Acked-by: Chanwoo Choi <[email-masked]>
>>> ---
>>> 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 <[email-masked]>
>>> + *
>>> + * 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 <[email-masked]>");
>>> +MODULE_DESCRIPTION("Rockchip dfi driver");
> s/dfi -> DFI
>
> Regards,
> Chanwoo Choi
>
>
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip

-- 
Lin Huang