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 Acked-by: Chanwoo Choi cw00.choi@samsung.com ---
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 1e8b4f4..96f2331 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 + (DDR Monitor Module) 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..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@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_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@rock-chips.com"); +MODULE_DESCRIPTION("Rockchip dfi driver");