[PATCH v6 7/8] PM / devfreq: rockchip: add devfreq driver for rk3399 dmc

Lin Huang
2016-08-16T22:37:25Z

base on dfi result, we do ddr frequency scaling, register
dmc driver to devfreq framework, and use simple-ondemand
policy.

Signed-off-by: Lin Huang <hl@rock-chips.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
---
Changes in v6:
- fix some nit suggest by Chanwoo Choi

Changes in v5:
- improve dmc driver suggest by Chanwoo Choi

Changes in v4:
- use arm_smccc_smc() function talk to bl31
- delete rockchip_dmc.c file and config
- delete dmc_notify
- adjust probe order

Changes in v3:
- operate dram setting through sip call
- imporve set rate flow

Changes in v2:
- None

Changes in v1:
- move dfi controller to event
- fix set voltage sequence when set rate fail
- change Kconfig type from tristate to bool
- move unuse EXPORT_SYMBOL_GPL()

drivers/devfreq/Kconfig | 11 +
drivers/devfreq/Makefile | 1 +
drivers/devfreq/rk3399_dmc.c | 497 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 509 insertions(+)
create mode 100644 drivers/devfreq/rk3399_dmc.c

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index a5be56e..e848121 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -100,6 +100,17 @@ config ARM_TEGRA_DEVFREQ
It reads ACTMON counters of memory controllers and adjusts the
operating frequencies and voltages with OPP support.

+config ARM_RK3399_DMC_DEVFREQ
+ tristate "ARM RK3399 DMC DEVFREQ Driver"
+ depends on ARCH_ROCKCHIP
+ select DEVFREQ_EVENT_ROCKCHIP_DFI
+ select DEVFREQ_GOV_SIMPLE_ONDEMAND
+ select PM_OPP
+ help
+ This adds the DEVFREQ driver for the RK3399 DMC(Dynamic Memory Controller).
+ It sets the frequency for the memory controller and reads the usage counts
+ from hardware.
+
source "drivers/devfreq/event/Kconfig"

endif # PM_DEVFREQ
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 09f11d9..fbff40a 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_DEVFREQ_GOV_PASSIVE) += governor_passive.o

# DEVFREQ Drivers
obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ) += exynos-bus.o
+obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ) += rk3399_dmc.o
obj-$(CONFIG_ARM_TEGRA_DEVFREQ) += tegra-devfreq.o

# DEVFREQ Event Drivers
diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
new file mode 100644
index 0000000..5f98f5e
--- /dev/null
+++ b/drivers/devfreq/rk3399_dmc.c
@@ -0,0 +1,497 @@
+/*
+ * 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/arm-smccc.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/devfreq.h>
+#include <linux/devfreq-event.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/regulator/consumer.h>
+#include <linux/rwsem.h>
+#include <linux/suspend.h>
+
+#include <soc/rockchip/rockchip_sip.h>
+
+struct dram_timing {
+ unsigned int ddr3_speed_bin;
+ unsigned int pd_idle;
+ unsigned int sr_idle;
+ unsigned int sr_mc_gate_idle;
+ unsigned int srpd_lite_idle;
+ unsigned int standby_idle;
+ unsigned int dram_dll_dis_freq;
+ unsigned int phy_dll_dis_freq;
+ unsigned int ddr3_odt_dis_freq;
+ unsigned int ddr3_drv;
+ unsigned int ddr3_odt;
+ unsigned int phy_ddr3_ca_drv;
+ unsigned int phy_ddr3_dq_drv;
+ unsigned int phy_ddr3_odt;
+ unsigned int lpddr3_odt_dis_freq;
+ unsigned int lpddr3_drv;
+ unsigned int lpddr3_odt;
+ unsigned int phy_lpddr3_ca_drv;
+ unsigned int phy_lpddr3_dq_drv;
+ unsigned int phy_lpddr3_odt;
+ unsigned int lpddr4_odt_dis_freq;
+ unsigned int lpddr4_drv;
+ unsigned int lpddr4_dq_odt;
+ unsigned int lpddr4_ca_odt;
+ unsigned int phy_lpddr4_ca_drv;
+ unsigned int phy_lpddr4_ck_cs_drv;
+ unsigned int phy_lpddr4_dq_drv;
+ unsigned int phy_lpddr4_odt;
+};
+
+struct rk3399_dmcfreq {
+ struct device *dev;
+ struct devfreq *devfreq;
+ struct devfreq_simple_ondemand_data ondemand_data;
+ struct clk *dmc_clk;
+ struct devfreq_event_dev *edev;
+ struct mutex lock;
+ struct dram_timing *timing;
+
+ /*
+ * DDR Converser of Frequency (DCF) is used to implement DDR frequency
+ * conversion without the participation of CPU, we will implement and
+ * control it in arm trust firmware.
+ */
+ wait_queue_head_t wait_dcf_queue;
+ int irq;
+ int wait_dcf_flag;
+ struct regulator *vdd_center;
+ unsigned long rate, target_rate;
+ unsigned long volt, target_volt;
+ struct dev_pm_opp *curr_opp;
+};
+
+static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
+ u32 flags)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
+ 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);
+
+ dmcfreq->rate = dev_pm_opp_get_freq(dmcfreq->curr_opp);
+ dmcfreq->volt = dev_pm_opp_get_voltage(dmcfreq->curr_opp);
+
+ rcu_read_unlock();
+
+ if (dmcfreq->rate == target_rate)
+ return 0;
+
+ mutex_lock(&dmcfreq->lock);
+
+ /*
+ * If frequency scaling from low to high, adjust voltage first.
+ * If frequency scaling from high to low, adjust frequency first.
+ */
+ if (old_clk_rate < target_rate) {
+ err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
+ target_volt);
+ if (err) {
+ dev_err(dev, "Cannot to set voltage %lu uV\n",
+ target_volt);
+ goto out;
+ }
+ }
+ dmcfreq->wait_dcf_flag = 1;
+
+ err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
+ if (err) {
+ dev_err(dev, "Cannot to set frequency %lu (%d)\n",
+ target_rate, err);
+ regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
+ dmcfreq->volt);
+ goto out;
+ }
+
+ /*
+ * Wait until bcf irq happen, it means freq scaling finish in
+ * arm trust firmware, use 100ms as timeout time.
+ */
+ if (!wait_event_timeout(dmcfreq->wait_dcf_queue,
+ !dmcfreq->wait_dcf_flag, HZ / 10))
+ dev_warn(dev, "Timeout waiting for dcf interrupt\n");
+
+ /*
+ * Check the dpll rate,
+ * There only two result we will get,
+ * 1. Ddr frequency scaling fail, we still get the old rate.
+ * 2. Ddr frequency scaling sucessful, we get the rate we set.
+ */
+ dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
+
+ /* If get the incorrect rate, set voltage to old value. */
+ if (dmcfreq->rate != target_rate) {
+ dev_err(dev, "Get wrong ddr frequency, Request frequency %lu,\
+ Current frequency %lu\n", target_rate, dmcfreq->rate);
+ regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
+ dmcfreq->volt);
+ goto out;
+ } else if (old_clk_rate > target_rate)
+ err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
+ target_volt);
+ if (err)
+ dev_err(dev, "Cannot to set vol %lu uV\n", target_volt);
+
+ dmcfreq->curr_opp = opp;
+out:
+ mutex_unlock(&dmcfreq->lock);
+ return err;
+}
+
+static int rk3399_dmcfreq_get_dev_status(struct device *dev,
+ struct devfreq_dev_status *stat)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
+ struct devfreq_event_data edata;
+ int ret = 0;
+
+ ret = devfreq_event_get_event(dmcfreq->edev, &edata);
+ if (ret < 0)
+ return ret;
+
+ stat->current_frequency = dmcfreq->rate;
+ stat->busy_time = edata.load_count;
+ stat->total_time = edata.total_count;
+
+ return ret;
+}
+
+static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
+
+ *freq = dmcfreq->rate;
+
+ return 0;
+}
+
+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,
+};
+
+static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
+ int ret = 0;
+
+ ret = devfreq_event_disable_edev(dmcfreq->edev);
+ if (ret < 0) {
+ dev_err(dev, "failed to disable the devfreq-event devices\n");
+ return ret;
+ }
+
+ ret = devfreq_suspend_device(dmcfreq->devfreq);
+ if (ret < 0) {
+ dev_err(dev, "failed to suspend the devfreq devices\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
+ int ret = 0;
+
+ ret = devfreq_event_enable_edev(dmcfreq->edev);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable the devfreq-event devices\n");
+ return ret;
+ }
+
+ ret = devfreq_resume_device(dmcfreq->devfreq);
+ if (ret < 0) {
+ dev_err(dev, "failed to resume the devfreq devices\n");
+ return ret;
+ }
+ return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
+ rk3399_dmcfreq_resume);
+
+static irqreturn_t rk3399_dmc_irq(int irq, void *dev_id)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_id;
+ struct arm_smccc_res res;
+
+ dmcfreq->wait_dcf_flag = 0;
+ wake_up(&dmcfreq->wait_dcf_queue);
+
+ /* Clear the DCF interrupt */
+ arm_smccc_smc(SIP_DRAM_FREQ, 0, 0, CONFIG_DRAM_CLR_IRQ,
+ 0, 0, 0, 0, &res);
+
+ return IRQ_HANDLED;
+}
+
+static struct dram_timing *of_get_ddr_timings(struct device *dev,
+ struct device_node *np)
+{
+ struct dram_timing *timing = NULL;
+ struct device_node *np_tim;
+ int ret;
+
+ np_tim = of_parse_phandle(np, "ddr_timing", 0);
+ if (np_tim) {
+ timing = devm_kzalloc(dev, sizeof(*timing), GFP_KERNEL);
+ if (!timing)
+ goto err;
+
+ ret = of_property_read_u32(np_tim, "ddr3_speed_bin",
+ &timing->ddr3_speed_bin);
+ ret |= of_property_read_u32(np_tim, "pd_idle",
+ &timing->pd_idle);
+ ret |= of_property_read_u32(np_tim, "sr_idle",
+ &timing->sr_idle);
+ ret |= of_property_read_u32(np_tim, "sr_mc_gate_idle",
+ &timing->sr_mc_gate_idle);
+ ret |= of_property_read_u32(np_tim, "srpd_lite_idle",
+ &timing->srpd_lite_idle);
+ ret |= of_property_read_u32(np_tim, "standby_idle",
+ &timing->standby_idle);
+ ret |= of_property_read_u32(np_tim, "dram_dll_dis_freq",
+ &timing->dram_dll_dis_freq);
+ ret |= of_property_read_u32(np_tim, "phy_dll_dis_freq",
+ &timing->phy_dll_dis_freq);
+ ret |= of_property_read_u32(np_tim, "ddr3_odt_dis_freq",
+ &timing->ddr3_odt_dis_freq);
+ ret |= of_property_read_u32(np_tim, "ddr3_drv",
+ &timing->ddr3_drv);
+ ret |= of_property_read_u32(np_tim, "ddr3_odt",
+ &timing->ddr3_odt);
+ ret |= of_property_read_u32(np_tim, "phy_ddr3_ca_drv",
+ &timing->phy_ddr3_ca_drv);
+ ret |= of_property_read_u32(np_tim, "phy_ddr3_dq_drv",
+ &timing->phy_ddr3_dq_drv);
+ ret |= of_property_read_u32(np_tim, "phy_ddr3_odt",
+ &timing->phy_ddr3_odt);
+ ret |= of_property_read_u32(np_tim, "lpddr3_odt_dis_freq",
+ &timing->lpddr3_odt_dis_freq);
+ ret |= of_property_read_u32(np_tim, "lpddr3_drv",
+ &timing->lpddr3_drv);
+ ret |= of_property_read_u32(np_tim, "lpddr3_odt",
+ &timing->lpddr3_odt);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr3_ca_drv",
+ &timing->phy_lpddr3_ca_drv);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr3_dq_drv",
+ &timing->phy_lpddr3_dq_drv);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr3_odt",
+ &timing->phy_lpddr3_odt);
+ ret |= of_property_read_u32(np_tim, "lpddr4_odt_dis_freq",
+ &timing->lpddr4_odt_dis_freq);
+ ret |= of_property_read_u32(np_tim, "lpddr4_drv",
+ &timing->lpddr4_drv);
+ ret |= of_property_read_u32(np_tim, "lpddr4_dq_odt",
+ &timing->lpddr4_dq_odt);
+ ret |= of_property_read_u32(np_tim, "lpddr4_ca_odt",
+ &timing->lpddr4_ca_odt);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr4_ca_drv",
+ &timing->phy_lpddr4_ca_drv);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr4_ck_cs_drv",
+ &timing->phy_lpddr4_ck_cs_drv);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr4_dq_drv",
+ &timing->phy_lpddr4_dq_drv);
+ ret |= of_property_read_u32(np_tim, "phy_lpddr4_odt",
+ &timing->phy_lpddr4_odt);
+ if (ret) {
+ devm_kfree(dev, timing);
+ goto err;
+ }
+ of_node_put(np_tim);
+ return timing;
+ }
+
+err:
+ if (timing) {
+ devm_kfree(dev, timing);
+ timing = NULL;
+ }
+ of_node_put(np_tim);
+ return timing;
+}
+
+static int rk3399_dmcfreq_probe(struct platform_device *pdev)
+{
+ struct arm_smccc_res res;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = pdev->dev.of_node;
+ struct rk3399_dmcfreq *data;
+ int ret, irq, index, size;
+ uint32_t *timing;
+ struct dev_pm_opp *opp;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Cannot get the dmc interrupt resource\n");
+ return -EINVAL;
+ }
+ data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ mutex_init(&data->lock);
+
+ data->vdd_center = devm_regulator_get(dev, "center");
+ if (IS_ERR(data->vdd_center)) {
+ dev_err(dev, "Cannot get the regulator \"center\"\n");
+ return PTR_ERR(data->vdd_center);
+ }
+
+ data->dmc_clk = devm_clk_get(dev, "dmc_clk");
+ if (IS_ERR(data->dmc_clk)) {
+ dev_err(dev, "Cannot get the clk dmc_clk\n");
+ return PTR_ERR(data->dmc_clk);
+ };
+
+ data->irq = irq;
+ ret = devm_request_irq(dev, irq, rk3399_dmc_irq, 0,
+ dev_name(dev), data);
+ if (ret) {
+ dev_err(dev, "Failed to request dmc irq: %d\n", ret);
+ return ret;
+ }
+
+
+ init_waitqueue_head(&data->wait_dcf_queue);
+ data->wait_dcf_flag = 0;
+
+ data->edev = devfreq_event_get_edev_by_phandle(dev, 0);
+ if (IS_ERR(data->edev))
+ return -EPROBE_DEFER;
+
+ ret = devfreq_event_enable_edev(data->edev);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable devfreq-event devices\n");
+ return ret;
+ }
+
+ /*
+ * Get dram timing and pass it to arm trust firmware,
+ * the dram drvier in arm trust firmware will get these
+ * timing and to do dram initial.
+ */
+ data->timing = of_get_ddr_timings(dev, np);
+ if (data->timing) {
+ timing = (uint32_t *)data->timing;
+ size = sizeof(struct dram_timing) / 4;
+ for (index = 0; index < size; index++) {
+ arm_smccc_smc(SIP_DRAM_FREQ, *timing++, index,
+ CONFIG_DRAM_SET_PARAM, 0, 0, 0, 0, &res);
+ if (res.a0) {
+ dev_err(dev, "Failed to set dram param: %ld\n",
+ res.a0);
+ return -EINVAL;
+ }
+ }
+ }
+
+ arm_smccc_smc(SIP_DRAM_FREQ, 0, 0, CONFIG_DRAM_INIT,
+ 0, 0, 0, 0, &res);
+
+ /*
+ * 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(dev)) {
+ dev_err(dev, "Invalid operating-points in device tree.\n");
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+
+ of_property_read_u32(np, "upthreshold",
+ &data->ondemand_data.upthreshold);
+ of_property_read_u32(np, "downdifferential",
+ &data->ondemand_data.downdifferential);
+
+ data->rate = clk_get_rate(data->dmc_clk);
+
+ rcu_read_lock();
+ opp = devfreq_recommended_opp(dev, &data->rate, 0);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ return PTR_ERR(opp);
+ }
+ rcu_read_unlock();
+ data->curr_opp = opp;
+
+ rk3399_devfreq_dmc_profile.initial_freq = data->rate;
+
+ data->devfreq = devfreq_add_device(dev,
+ &rk3399_devfreq_dmc_profile,
+ "simple_ondemand",
+ &data->ondemand_data);
+ if (IS_ERR(data->devfreq))
+ return PTR_ERR(data->devfreq);
+ devm_devfreq_register_opp_notifier(dev, data->devfreq);
+
+ data->dev = dev;
+ platform_set_drvdata(pdev, data);
+
+ return 0;
+}
+
+static int rk3399_dmcfreq_remove(struct platform_device *pdev)
+{
+ struct rk3399_dmcfreq *dmcfreq = platform_get_drvdata(pdev);
+
+ regulator_put(dmcfreq->vdd_center);
+
+ return 0;
+}
+
+static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
+ { .compatible = "rockchip,rk3399-dmc" },
+ { },
+};
+
+static struct platform_driver rk3399_dmcfreq_driver = {
+ .probe = rk3399_dmcfreq_probe,
+ .remove = rk3399_dmcfreq_remove,
+ .driver = {
+ .name = "rk3399-dmc-freq",
+ .pm = &rk3399_dmcfreq_pm,
+ .of_match_table = rk3399dmc_devfreq_of_match,
+ },
+};
+module_platform_driver(rk3399_dmcfreq_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
+MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");
--
2.6.6