blob: 39ac069cabc756c93bd38b2f8c11aff42ed6bd7e [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
* Author: Lin Huang <hl@rock-chips.com>
*/
#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>
#include <soc/rockchip/rk3399_grf.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 SOFTWARE_DIS (0x10000 << 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
struct dmc_usage {
u32 access;
u32 total;
};
/*
* The dfi controller can monitor DDR load. It has an upper and lower threshold
* for the operating points. Whenever the usage leaves these bounds an event is
* generated to indicate the DDR frequency should be changed.
*/
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, RK3399_PMUGRF_OS_REG2, &val);
ddr_type = (val >> RK3399_PMUGRF_DDRTYPE_SHIFT) &
RK3399_PMUGRF_DDRTYPE_MASK;
/* clear DDRMON_CTRL setting */
writel_relaxed(CLR_DDRMON_CTRL, dfi_regs + DDRMON_CTRL);
/* set ddr type to dfi */
if (ddr_type == RK3399_PMUGRF_DDRTYPE_LPDDR3)
writel_relaxed(LPDDR3_EN, dfi_regs + DDRMON_CTRL);
else if (ddr_type == RK3399_PMUGRF_DDRTYPE_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;
writel_relaxed(SOFTWARE_DIS, 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) * 4;
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" },
{ },
};
MODULE_DEVICE_TABLE(of, rockchip_dfi_id_match);
static int rockchip_dfi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct rockchip_dfi *data;
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;
data->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(data->regs))
return PTR_ERR(data->regs);
data->clk = devm_clk_get(dev, "pclk_ddr_mon");
if (IS_ERR(data->clk))
return dev_err_probe(dev, PTR_ERR(data->clk),
"Cannot get the clk pclk_ddr_mon\n");
/* 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);
of_node_put(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");