The i.MX7Dual/Solo is a new series of the i.MX SOC family.
The existing cpufreq driver for 'i.MX6' or 'cpufreq-dt' can
NOT match the requirement of this new SOC. This patch adds the
cpufreq driver for i.MX7Dual/Solo.
Signed-off-by: Bai Ping <b51...@freescale.com>
---
drivers/cpufreq/Kconfig.arm | 10 ++
drivers/cpufreq/Makefile | 1 +
drivers/cpufreq/imx7d-cpufreq.c | 257 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 268 insertions(+)
create mode 100644 drivers/cpufreq/imx7d-cpufreq.c
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index 8014c23..adddfd7 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -67,6 +67,16 @@ config ARM_IMX6Q_CPUFREQ
If in doubt, say N.
+config ARM_IMX7D_CPUFREQ
+ tristate "Freescale i.MX7 cpufreq support"
+ depends on ARCH_MXC
+ select PM_OPP
+ help
+ This adds cpufreq driver support for Freescale i.MX7Dual/Solo
+ series SoCs.
+
+ If in doubt, say N.
+
config ARM_INTEGRATOR
tristate "CPUfreq driver for ARM Integrator CPUs"
depends on ARCH_INTEGRATOR
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index c0af1a1..66723a0 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_ARM_EXYNOS5440_CPUFREQ) += exynos5440-cpufreq.o
obj-$(CONFIG_ARM_HIGHBANK_CPUFREQ) += highbank-cpufreq.o
obj-$(CONFIG_ARM_HISI_ACPU_CPUFREQ) += hisi-acpu-cpufreq.o
obj-$(CONFIG_ARM_IMX6Q_CPUFREQ) += imx6q-cpufreq.o
+obj-$(CONFIG_ARM_IMX7D_CPUFREQ) += imx7d-cpufreq.o
obj-$(CONFIG_ARM_INTEGRATOR) += integrator-cpufreq.o
obj-$(CONFIG_ARM_KIRKWOOD_CPUFREQ) += kirkwood-cpufreq.o
obj-$(CONFIG_ARM_MT8173_CPUFREQ) += mt8173-cpufreq.o
diff --git a/drivers/cpufreq/imx7d-cpufreq.c b/drivers/cpufreq/imx7d-cpufreq.c
new file mode 100644
index 0000000..7506702
--- /dev/null
+++ b/drivers/cpufreq/imx7d-cpufreq.c
@@ -0,0 +1,257 @@
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+static struct clk *arm_clk;
+static struct clk *pll_arm;
+static struct clk *arm_src;
+static struct clk *pll_sys_main;
+
+static struct regulator *arm_reg;
+
+static struct device *cpu_dev;
+static bool free_opp;
+static struct cpufreq_frequency_table *freq_table;
+static unsigned int transition_latency;
+
+static int imx7d_set_target(struct cpufreq_policy *policy, unsigned int index)
+{
+ struct dev_pm_opp *opp;
+ unsigned long freq_hz, volt, volt_old;
+ unsigned int old_freq, new_freq;
+ int ret;
+
+ new_freq = freq_table[index].frequency;
+ freq_hz = new_freq * 1000;
+ old_freq = clk_get_rate(arm_clk) / 1000;
+
+ rcu_read_lock();
+ opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ dev_err(cpu_dev, "failed to find OPP for %ld\n", freq_hz);
+ return PTR_ERR(opp);
+ }
+ volt = dev_pm_opp_get_voltage(opp);
+ rcu_read_unlock();
+ volt_old = regulator_get_voltage(arm_reg);
+
+ dev_dbg(cpu_dev, "%u MHz, %ld mV --> %u MHz, %ld mV\n",
+ old_freq / 1000, volt_old / 1000,
+ new_freq / 1000, volt / 1000);
+
+ /* Scaling up? scale voltage before frequency */
+ if (new_freq > old_freq) {
+ ret = regulator_set_voltage_tol(arm_reg, volt, 0);
+ if (ret) {
+ dev_err(cpu_dev, "failed to scale vddarm up: %d\n",
ret);
+ return ret;
+ }
+ }
+
+ /* before changing pll_arm rate, change the arm_src's soure
+ * to pll_sys_main clk first.
+ */
+ clk_set_parent(arm_src, pll_sys_main);
+ clk_set_rate(pll_arm, new_freq * 1000);
+ clk_set_parent(arm_src, pll_arm);
+
+ /* change the cpu frequency */
+ ret = clk_set_rate(arm_clk, new_freq * 1000);
+ if (ret) {
+ dev_err(cpu_dev, " failed to set clock rate: %d\n", ret);
+ regulator_set_voltage_tol(arm_reg, volt_old, 0);
+ return ret;
+ }
+
+ /* scaling down? scaling voltage after frequency */
+ if (new_freq < old_freq) {
+ ret = regulator_set_voltage_tol(arm_reg, volt, 0);
+ if (ret) {
+ dev_warn(cpu_dev, "failed to scale vddarm down: %d\n",
ret);
+ ret = 0;
+ }
+ }
+
+ return 0;
+}
+
+static int imx7d_cpufreq_init(struct cpufreq_policy *policy)
+{
+ policy->clk = arm_clk;
+ policy->cur = clk_get_rate(arm_clk) / 1000;
+
+ return cpufreq_generic_init(policy, freq_table, transition_latency);
+}
+
+static struct cpufreq_driver imx7d_cpufreq_driver = {
+ .flags = CPUFREQ_NEED_INITIAL_FREQ_CHECK,
+ .verify = cpufreq_generic_frequency_table_verify,
+ .target_index = imx7d_set_target,
+ .get = cpufreq_generic_get,
+ .init = imx7d_cpufreq_init,
+ .name = "imx7d-cpufreq",
+ .attr = cpufreq_generic_attr,
+};
+
+static int imx7d_cpufreq_probe(struct platform_device *pdev)
+{
+ struct device_node *np;
+ struct dev_pm_opp *opp;
+ unsigned long min_volt, max_volt;
+ int num, ret;
+
+ cpu_dev = get_cpu_device(0);
+ if (!cpu_dev) {
+ pr_err("failed to get cpu0 device\n");
+ return -ENODEV;
+ }
+
+ np = of_node_get(cpu_dev->of_node);
+ if (!np) {
+ dev_err(cpu_dev, "failed to find the cpu0 node\n");
+ return -ENOENT;
+ }
+
+ arm_clk = clk_get(cpu_dev, "arm");
+ arm_src = clk_get(cpu_dev, "arm_root_src");
+ pll_arm = clk_get(cpu_dev, "pll_arm");
+ pll_sys_main = clk_get(cpu_dev, "pll_sys_main");
+
+ if (IS_ERR(arm_clk) || IS_ERR(arm_src) || IS_ERR(pll_arm) ||
+ IS_ERR(pll_sys_main)) {
+ dev_err(cpu_dev, "failed to get clocks\n");
+ ret = -ENOENT;
+ goto put_clk;
+ }
+
+ arm_reg = devm_regulator_get(cpu_dev, "arm");
+ if (IS_ERR(arm_reg)) {
+ ret = PTR_ERR(arm_reg);
+ if (ret != -EPROBE_DEFER)
+ dev_err(cpu_dev, "failed to get the regulator\n");
+
+ goto put_clk;
+ }
+
+ /* We expect an OPP table supplied by platform.
+ * Just incase the platform did not supply the OPP
+ * table, it will try to get it.
+ */
+ num = dev_pm_opp_get_opp_count(cpu_dev);
+ if (num < 0) {
+ ret = dev_pm_opp_of_add_table(cpu_dev);
+ if (ret < 0) {
+ dev_err(cpu_dev, "failed to init OPP table: %d\n", ret);
+ goto put_reg;
+ }
+
+ free_opp = true;
+
+ num = dev_pm_opp_get_opp_count(cpu_dev);
+ if (num < 0) {
+ ret = num;
+ dev_err(cpu_dev, "no OPP table is found: %d\n", ret);
+ goto out_free_opp;
+ }
+ }
+
+ ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
+ if (ret) {
+ dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret);
+ goto out_free_opp;
+ }
+
+ if (of_property_read_u32(np, "clock-latency", &transition_latency))
+ transition_latency = CPUFREQ_ETERNAL;
+
+ /* OPP is maintained in order of increasing frequency, and
+ * freq_table initialized from OPP is therefore sorted in the
+ * same order
+ */
+ rcu_read_lock();
+ opp = dev_pm_opp_find_freq_exact(cpu_dev,
+ freq_table[0].frequency * 1000, true);
+ min_volt = dev_pm_opp_get_voltage(opp);
+ opp = dev_pm_opp_find_freq_exact(cpu_dev,
+ freq_table[--num].frequency * 1000, true);
+ max_volt = dev_pm_opp_get_voltage(opp);
+ rcu_read_unlock();
+ ret = regulator_set_voltage_time(arm_reg, min_volt, max_volt);
+ if (ret > 0)
+ transition_latency += ret * 1000;
+
+ ret = cpufreq_register_driver(&imx7d_cpufreq_driver);
+ if (ret) {
+ dev_err(cpu_dev, "failed register driver: %d\n", ret);
+ goto free_freq_table;
+ }
+
+ of_node_put(np);
+ return 0;
+
+free_freq_table:
+ dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
+out_free_opp:
+ if (free_opp)
+ dev_pm_opp_of_remove_table(cpu_dev);
+put_reg:
+ if (!IS_ERR(arm_reg))
+ regulator_put(arm_reg);
+put_clk:
+ if (!IS_ERR(arm_clk))
+ clk_put(arm_clk);
+ if (!IS_ERR(arm_src))
+ clk_put(arm_src);
+ if (!IS_ERR(pll_arm))
+ clk_put(pll_arm);
+ if (!IS_ERR(pll_sys_main))
+ clk_put(pll_sys_main);
+ of_node_put(np);
+
+ return ret;
+}
+
+static int imx7d_cpufreq_remove(struct platform_device *pdev)
+{
+ cpufreq_unregister_driver(&imx7d_cpufreq_driver);
+ dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
+ dev_pm_opp_of_remove_table(cpu_dev);
+
+ regulator_put(arm_reg);
+
+ clk_put(arm_clk);
+ clk_put(arm_src);
+ clk_put(pll_arm);
+ clk_put(pll_sys_main);
+
+ return 0;
+}
+
+static struct platform_driver imx7d_cpufreq_platdrv = {
+ .driver = {
+ .name = "imx7d-cpufreq",
+ .owner = THIS_MODULE,
+ },
+ .probe = imx7d_cpufreq_probe,
+ .remove = imx7d_cpufreq_remove,
+};
+
+module_platform_driver(imx7d_cpufreq_platdrv);
+
+MODULE_DESCRIPTION("Freescale i.MX7D cpufreq driver");
+MODULE_LICENSE("GPL");
--
1.9.1
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