[PATCH 2/2] devfreq: rockchip: support rk3399 dmc devfreq
Lin Huang
hl at rock-chips.com
Thu Nov 19 02:21:11 PST 2015
rk3399 do ddr frequency scaling use devfreq framework,
use simple_ondemand policy, and use rk3399 dfi controller
to get ddr busy time.
Signed-off-by: Lin Huang <hl at rock-chips.com>
---
drivers/devfreq/Kconfig | 1 +
drivers/devfreq/Makefile | 1 +
drivers/devfreq/rockchip/Kconfig | 8 +
drivers/devfreq/rockchip/Makefile | 1 +
drivers/devfreq/rockchip/rk3399_dmc.c | 327 ++++++++++++++++++++++++++++++++++
5 files changed, 338 insertions(+)
create mode 100644 drivers/devfreq/rockchip/Kconfig
create mode 100644 drivers/devfreq/rockchip/Makefile
create mode 100644 drivers/devfreq/rockchip/rk3399_dmc.c
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 64281bb..acb2a57 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -99,5 +99,6 @@ config ARM_TEGRA_DEVFREQ
operating frequencies and voltages with OPP support.
source "drivers/devfreq/event/Kconfig"
+source "drivers/devfreq/rockchip/Kconfig"
endif # PM_DEVFREQ
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 5134f9e..d844e23 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_DEVFREQ_GOV_USERSPACE) += governor_userspace.o
obj-$(CONFIG_ARM_EXYNOS4_BUS_DEVFREQ) += exynos/
obj-$(CONFIG_ARM_EXYNOS5_BUS_DEVFREQ) += exynos/
obj-$(CONFIG_ARM_TEGRA_DEVFREQ) += tegra-devfreq.o
+obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
# DEVFREQ Event Drivers
obj-$(CONFIG_PM_DEVFREQ_EVENT) += event/
diff --git a/drivers/devfreq/rockchip/Kconfig b/drivers/devfreq/rockchip/Kconfig
new file mode 100644
index 0000000..ceb7f37
--- /dev/null
+++ b/drivers/devfreq/rockchip/Kconfig
@@ -0,0 +1,8 @@
+config ARM_RK3399_DMC_DEVFREQ
+ tristate "ARM RK3399 DMC DEVFREQ Driver"
+ depends on ARCH_ROCKCHIP
+ select PM_OPP
+ select DEVFREQ_GOV_SIMPLE_ONDEMAND
+ help
+ This adds the DEVFREQ driver for the RK3399 dmc. It sets the frequency
+ for the memory controller and reads the usage counts from hardware.
diff --git a/drivers/devfreq/rockchip/Makefile b/drivers/devfreq/rockchip/Makefile
new file mode 100644
index 0000000..c62c105
--- /dev/null
+++ b/drivers/devfreq/rockchip/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ) += rk3399_dmc.o
diff --git a/drivers/devfreq/rockchip/rk3399_dmc.c b/drivers/devfreq/rockchip/rk3399_dmc.c
new file mode 100644
index 0000000..6bf4230
--- /dev/null
+++ b/drivers/devfreq/rockchip/rk3399_dmc.c
@@ -0,0 +1,327 @@
+/*
+ * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
+ *
+ * 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/completion.h>
+#include <linux/delay.h>
+#include <linux/devfreq.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/rwsem.h>
+#include <linux/suspend.h>
+#include <linux/syscore_ops.h>
+#include <soc/rockchip/rk3399-dmc-clk.h>
+
+#define RK3399_DMC_NUM_CH 2
+
+/* DDRMON_CTRL */
+#define DDRMON_CTRL 0x04
+#define LPDDR4_EN (1 << 4)
+#define HARDWARE_EN (1 << 3)
+#define LPDDR3_EN (1 << 2)
+#define SOFTWARE_EN (1 << 1)
+#define TIME_CNT_EN (1 << 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;
+};
+
+struct rk3399_dmcfreq {
+ struct device *clk_dev;
+ struct devfreq *devfreq;
+ struct devfreq_simple_ondemand_data ondemand_data;
+ struct clk *dmc_clk;
+ struct regulator *vdd_logic;
+ struct dmc_usage ch_usage[RK3399_DMC_NUM_CH];
+ struct rk3399_dmcclk *dmc_data;
+ struct mutex lock;
+ unsigned long rate, target_rate;
+ unsigned long volt, target_volt;
+};
+
+static struct rk3399_dmcfreq dmcfreq;
+
+static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
+ u32 flags)
+{
+ struct dev_pm_opp *opp;
+ unsigned long old_clk_rate = dmcfreq.rate;
+ unsigned long target_volt, target_rate;
+ int err;
+
+ rcu_read_lock();
+ opp = devfreq_recommended_opp(dev, freq, flags);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ return PTR_ERR(opp);
+ }
+ target_rate = dev_pm_opp_get_freq(opp);
+ target_volt = dev_pm_opp_get_voltage(opp);
+
+ opp = devfreq_recommended_opp(dev, &dmcfreq.rate, flags);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ return PTR_ERR(opp);
+ }
+ dmcfreq.volt = dev_pm_opp_get_voltage(opp);
+ rcu_read_unlock();
+
+ if (dmcfreq.rate == dmcfreq.target_rate)
+ return 0;
+
+ mutex_lock(&dmcfreq.lock);
+
+ if (old_clk_rate < target_rate) {
+ err = regulator_set_voltage(dmcfreq.vdd_logic, target_volt,
+ target_volt);
+ if (err) {
+ dev_err(dev, "Unable to set vol %lu\n", target_volt);
+ goto out;
+ }
+ }
+
+ err = clk_set_rate(dmcfreq.dmc_clk, target_rate);
+ if (err) {
+ dev_err(dev,
+ "Unable to set freq %lu. Current freq %lu. Error %d\n",
+ target_rate, old_clk_rate, err);
+ regulator_set_voltage(dmcfreq.vdd_logic, dmcfreq.volt,
+ dmcfreq.volt);
+ goto out;
+ }
+
+ dmcfreq.rate = target_rate;
+
+ if (old_clk_rate > target_rate)
+ err = regulator_set_voltage(dmcfreq.vdd_logic, target_volt,
+ target_volt);
+ if (err)
+ dev_err(dev, "Unable to set vol %lu\n", target_volt);
+out:
+ mutex_unlock(&dmcfreq.lock);
+ return err;
+}
+
+static void rk3399_dmc_start_hardware_counter(void)
+{
+ void __iomem *ctrl_regs = dmcfreq.dmc_data->ctrl_regs;
+ void __iomem *dfi_regs = dmcfreq.dmc_data->dfi_regs;
+ u32 val;
+ u32 ddr_type;
+
+ /* get ddr type */
+ val = readl_relaxed(ctrl_regs + DENALI_CTL_00);
+ ddr_type = (val >> DRAM_CLASS_SHIFT) & DRAM_CLASS_MASK;
+
+ /* set ddr type to dfi */
+ val = readl_relaxed(dfi_regs + DDRMON_CTRL);
+ if (ddr_type == LPDDR3) {
+ val &= ~LPDDR4_EN;
+ val |= LPDDR3_EN;
+ } else if (ddr_type == LPDDR4) {
+ val &= ~LPDDR3_EN;
+ val |= LPDDR4_EN;
+ } else
+ val &= ~(LPDDR3_EN | LPDDR4_EN);
+
+ /* enable count, use software mode */
+ val &= ~HARDWARE_EN;
+ val |= SOFTWARE_EN;
+
+ writel_relaxed(val, dfi_regs + DDRMON_CTRL);
+}
+
+static void rk3399_dmc_stop_hardware_counter(void)
+{
+ void __iomem *dfi_regs = dmcfreq.dmc_data->dfi_regs;
+ u32 val;
+
+ val = readl_relaxed(dfi_regs + DDRMON_CTRL);
+ val &= ~SOFTWARE_EN;
+ writel_relaxed(val, dfi_regs + DDRMON_CTRL);
+}
+
+static int rk3399_dmc_get_busier_ch(void)
+{
+ u32 tmp, max = 0;
+ u32 i, busier_ch = 0;
+ void __iomem *dfi_regs = dmcfreq.dmc_data->dfi_regs;
+
+ rk3399_dmc_stop_hardware_counter();
+
+ /* Find out which channel is busier */
+ for (i = 0; i < RK3399_DMC_NUM_CH; i++) {
+ dmcfreq.ch_usage[i].access = readl_relaxed(dfi_regs +
+ DDRMON_CH0_DFI_ACCESS_NUM + i * 20);
+ dmcfreq.ch_usage[i].total = readl_relaxed(dfi_regs +
+ DDRMON_CH0_COUNT_NUM + i * 20);
+ tmp = dmcfreq.ch_usage[i].access;
+ if (tmp > max) {
+ busier_ch = i;
+ max = tmp;
+ }
+ }
+ rk3399_dmc_start_hardware_counter();
+
+ return busier_ch;
+}
+
+static int rk3399_dmcfreq_get_dev_status(struct device *dev,
+ struct devfreq_dev_status *stat)
+{
+ int busier_ch;
+
+ busier_ch = rk3399_dmc_get_busier_ch();
+ stat->current_frequency = dmcfreq.rate;
+ stat->busy_time = dmcfreq.ch_usage[busier_ch].access;
+ stat->total_time = dmcfreq.ch_usage[busier_ch].total;
+
+ return 0;
+}
+
+static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+ *freq = dmcfreq.rate;
+ return 0;
+}
+
+static void rk3399_dmcfreq_exit(struct device *dev)
+{
+ devfreq_unregister_opp_notifier(dmcfreq.clk_dev, dmcfreq.devfreq);
+}
+
+static struct devfreq_dev_profile rk3399_devfreq_dmc_profile = {
+ .polling_ms = 200,
+ .target = rk3399_dmcfreq_target,
+ .get_dev_status = rk3399_dmcfreq_get_dev_status,
+ .get_cur_freq = rk3399_dmcfreq_get_cur_freq,
+ .exit = rk3399_dmcfreq_exit,
+};
+
+static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
+{
+ unsigned long freq = ULONG_MAX;
+
+ dev_info(dmcfreq.clk_dev, "suspending DVFS and going to max freq\n");
+ devfreq_suspend_device(dmcfreq.devfreq);
+ rk3399_dmc_stop_hardware_counter();
+ rk3399_dmcfreq_target(dmcfreq.clk_dev, &freq, 0);
+
+ return 0;
+}
+
+static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
+{
+ dev_info(dmcfreq.clk_dev, "resuming DVFS\n");
+ rk3399_dmc_start_hardware_counter();
+ devfreq_resume_device(dmcfreq.devfreq);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
+ rk3399_dmcfreq_resume);
+
+static void rk3399_dmcfreq_shutdown(void)
+{
+ devfreq_suspend_device(dmcfreq.devfreq);
+}
+
+static struct syscore_ops rk3399_dmcfreq_syscore_ops = {
+ .shutdown = rk3399_dmcfreq_shutdown,
+};
+
+static int rk3399_dmcfreq_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+
+ dmcfreq.clk_dev = dev->parent;
+ mutex_init(&dmcfreq.lock);
+
+ dmcfreq.dmc_data =
+ (struct rk3399_dmcclk *)dev_get_drvdata(dmcfreq.clk_dev);
+
+ dmcfreq.vdd_logic = regulator_get(dmcfreq.clk_dev, "logic");
+ if (IS_ERR(dmcfreq.vdd_logic)) {
+ dev_err(dev, "Cannot get the regulator \"vdd_logic\"\n");
+ return PTR_ERR(dmcfreq.vdd_logic);
+ }
+
+ dmcfreq.dmc_clk = devm_clk_get(dev, "dmc_clk");
+ if (IS_ERR(dmcfreq.dmc_clk)) {
+ dev_err(dev, "Cannot get the clk dmc_clk\n");
+ return PTR_ERR(dmcfreq.dmc_clk);
+ };
+
+ /*
+ * We add a devfreq driver to our parent since it has a device tree node
+ * with operating points.
+ */
+ if (dev_pm_opp_of_add_table(dmcfreq.clk_dev)) {
+ dev_err(dev, "Invalid operating-points in device tree.\n");
+ return -EINVAL;
+ }
+
+ of_property_read_u32(dmcfreq.clk_dev->of_node, "upthreshold",
+ &dmcfreq.ondemand_data.upthreshold);
+
+ of_property_read_u32(dmcfreq.clk_dev->of_node, "downdifferential",
+ &dmcfreq.ondemand_data.downdifferential);
+
+ dmcfreq.devfreq = devfreq_add_device(dmcfreq.clk_dev,
+ &rk3399_devfreq_dmc_profile,
+ "simple_ondemand",
+ &dmcfreq.ondemand_data);
+ if (IS_ERR(dmcfreq.devfreq))
+ return PTR_ERR(dmcfreq.devfreq);
+
+ devfreq_register_opp_notifier(dmcfreq.clk_dev, dmcfreq.devfreq);
+
+ register_syscore_ops(&rk3399_dmcfreq_syscore_ops);
+
+ return 0;
+}
+
+static int rk3399_dmcfreq_remove(struct platform_device *pdev)
+{
+ devfreq_remove_device(dmcfreq.devfreq);
+ regulator_put(dmcfreq.vdd_logic);
+
+ return 0;
+}
+
+static struct platform_driver rk3399_dmcfreq_driver = {
+ .probe = rk3399_dmcfreq_probe,
+ .remove = rk3399_dmcfreq_remove,
+ .driver = {
+ .name = "rk3399-dmc-freq",
+ .pm = &rk3399_dmcfreq_pm,
+ },
+};
+module_platform_driver(rk3399_dmcfreq_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
--
1.9.1
More information about the Linux-rockchip
mailing list