Re: [RFC PATCH v1 4/6] PM / devfreq: event: support rockchip dfi controller

hl
2016-06-06T03:50:43Z

On 2016年06月03日 18:26, Chanwoo Choi wrote:
> Hi Lin,
>
> I add the some comment on below. If you modify it,
> You can add my acked-by tag. Looks good to me.
Thanks for you reviewing, i will update the code folloiwing your comment.
> Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
>
> Also, I'd like you to add me to mail thread
> on next version because I'm supporter of devfreq-event.
I am sorry for missing you mail in before patch:-[ , will add you to
mail thread next vesion.
> On 2016년 06월 03일 18:55, 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@rock-chips.com>
>> ---
>> Changes in v1:
>> - NOne
>>
>> drivers/devfreq/event/Kconfig | 7 +
>> drivers/devfreq/event/Makefile | 1 +
>> drivers/devfreq/event/rockchip-dfi.c | 265 +++++++++++++++++++++++++++++++++++
>> 3 files changed, 273 insertions(+)
>> create mode 100644 drivers/devfreq/event/rockchip-dfi.c
>>
>> diff --git a/drivers/devfreq/event/Kconfig b/drivers/devfreq/event/Kconfig
>> index 1e8b4f4..6ebdc13 100644
>> --- a/drivers/devfreq/event/Kconfig
>> +++ b/drivers/devfreq/event/Kconfig
>> @@ -30,4 +30,11 @@ config DEVFREQ_EVENT_EXYNOS_PPMU
>> (Platform Performance Monitoring Unit) counters to estimate the
>> utilization of each module.
>>
>> +config DEVFREQ_EVENT_ROCKCHIP_DFI
>> + bool "ROCKCHIP DFI DEVFREQ event Driver"
>> + depends on ARCH_ROCKCHIP
>> + help
>> + This add the devfreq-event driver for Rockchip SoC. It provides DFI
> You better to full name of 'DFI' abbreviation as following:
> - DFI (Dxxx Fxxx Ixxx)
>
>> + driver to count ddr load.
>> +
>> endif # PM_DEVFREQ_EVENT
>> diff --git a/drivers/devfreq/event/Makefile b/drivers/devfreq/event/Makefile
>> index 3d6afd3..dda7090 100644
>> --- a/drivers/devfreq/event/Makefile
>> +++ b/drivers/devfreq/event/Makefile
>> @@ -2,3 +2,4 @@
>>
>> obj-$(CONFIG_DEVFREQ_EVENT_EXYNOS_NOCP) += exynos-nocp.o
>> obj-$(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..e3b020f9
>> --- /dev/null
>> +++ b/drivers/devfreq/event/rockchip-dfi.c
>> @@ -0,0 +1,265 @@
>> +/*
>> + * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
>> + * Author: Lin Huang <hl@rock-chips.com>
>> + *
>> + * 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(info->clk);
> I prefer to change the function as following. I add the comment on below in probe()
> - clk_disable -> clk_disable_unprepare()
>
>
>> +
>> + 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_enable(info->clk);
> I prefer to change the function as following. I add the comment on below in probe()
> - clk_enable -> clk_prepare_enable()
>
>> + if (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;
>> + int ret;
>> + 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)) {
>> + ret = PTR_ERR(data->edev);
>> + dev_err(&pdev->dev,
>> + "failed to add devfreq-event device\n");
>> + return ret;
> You can simply return the PTR_ERR(data->edev) without 'ret' variable as following:
>
> return PTR_ERR(data->edev);
>
>
>> + }
>> +
>> + ret = clk_prepare_enable(data->clk);
>> + if (ret) {
>> + dev_err(&pdev->dev, "failed to enable clk: %d\n", ret);
>> + clk_disable_unprepare(data->clk);
>> + return ret;
>> + }
> The following two functions handle the clock. So, rockchip_dfi_probe()
> don't need to enable the clock. Just pass the role of clock control to the following functions.
> Because of calling the twice of enable function of clock, the usage count of clock
> is mismatch when disabling the clock.
> - rockchip_dfi_enable(struct devfreq_event_dev *edev) enable the clock.
> - rockchip_dfi_disable(struct devfreq_event_dev *edev) disable the clock.
>
>
>> +
>> + platform_set_drvdata(pdev, data);
>> +
>> + return 0;
>> +}
>> +
>> +static int rockchip_dfi_remove(struct platform_device *pdev)
>> +{
>> + return 0;
>> +}
> If the rockchip_dfi_remove() don't do anything, you can remove it
>
>> +
>> +static struct platform_driver rockchip_dfi_driver = {
>> + .probe = rockchip_dfi_probe,
>> + .remove = rockchip_dfi_remove,
> ditto.
>
>> + .driver = {
>> + .name = "rockchip-dfi",
>> + .of_match_table = rockchip_dfi_id_match,
>> + },
>> +};
>> +module_platform_driver(rockchip_dfi_driver);
>> +
>> +MODULE_LICENSE("GPL v2");
> You need to add MODULE_AUTHOR("").
>
>> +MODULE_DESCRIPTION("Rockchip dfi driver");
>>
> Remove unneeded blank line
>
> Regards,
> Chanwoo Choi
>
>
>
>

--
Lin Huang