Merge tag 'tegra-for-4.3-cpufreq' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into next/drivers

ARM: tegra: CPU frequency scaling for v4.3-rc1

This adds CPU frequency scaling support for Tegra124.

* tag 'tegra-for-4.3-cpufreq' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
  cpufreq: Add cpufreq driver for Tegra124
  cpufreq: tegra: Rename tegra-cpufreq to tegra20-cpufreq
  cpufreq: tegra124: Add device tree bindings

Signed-off-by: Olof Johansson <olof@lixom.net>

5 files changed, 270 insertions, 4 deletions

diff --git a/Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt b/Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt
new file mode 100644
index 000000000000..b1669fbfb740
--- /dev/null
+++ b/Documentation/devicetree/bindings/cpufreq/tegra124-cpufreq.txt
@@ -0,0 +1,44 @@
+Tegra124 CPU frequency scaling driver bindings
+----------------------------------------------
+
+Both required and optional properties listed below must be defined
+under node /cpus/cpu@0.
+
+Required properties:
+- clocks: Must contain an entry for each entry in clock-names.
+  See ../clocks/clock-bindings.txt for details.
+- clock-names: Must include the following entries:
+  - cpu_g: Clock mux for the fast CPU cluster.
+  - cpu_lp: Clock mux for the low-power CPU cluster.
+  - pll_x: Fast PLL clocksource.
+  - pll_p: Auxiliary PLL used during fast PLL rate changes.
+  - dfll: Fast DFLL clocksource that also automatically scales CPU voltage.
+- vdd-cpu-supply: Regulator for CPU voltage
+
+Optional properties:
+- clock-latency: Specify the possible maximum transition latency for clock,
+  in unit of nanoseconds.
+
+Example:
+--------
+cpus {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        cpu@0 {
+                device_type = "cpu";
+                compatible = "arm,cortex-a15";
+                reg = <0>;
+
+                clocks = <&tegra_car TEGRA124_CLK_CCLK_G>,
+                         <&tegra_car TEGRA124_CLK_CCLK_LP>,
+                         <&tegra_car TEGRA124_CLK_PLL_X>,
+                         <&tegra_car TEGRA124_CLK_PLL_P>,
+                         <&dfll>;
+                clock-names = "cpu_g", "cpu_lp", "pll_x", "pll_p", "dfll";
+                clock-latency = <300000>;
+                vdd-cpu-supply: <&vdd_cpu>;
+        };
+
+        <...>
+};
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index cc8a71c267b8..24e5c664683f 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -247,12 +247,19 @@ config ARM_SPEAR_CPUFREQ
         help
           This adds the CPUFreq driver support for SPEAr SOCs.
 
-config ARM_TEGRA_CPUFREQ
-        bool "TEGRA CPUFreq support"
+config ARM_TEGRA20_CPUFREQ
+        bool "Tegra20 CPUFreq support"
         depends on ARCH_TEGRA
         default y
         help
-          This adds the CPUFreq driver support for TEGRA SOCs.
+          This adds the CPUFreq driver support for Tegra20 SOCs.
+
+config ARM_TEGRA124_CPUFREQ
+        tristate "Tegra124 CPUFreq support"
+        depends on ARCH_TEGRA && CPUFREQ_DT
+        default y
+        help
+          This adds the CPUFreq driver support for Tegra124 SOCs.
 
 config ARM_PXA2xx_CPUFREQ
         tristate "Intel PXA2xx CPUfreq driver"
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index 2169bf792db7..032745de8fcc 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -76,7 +76,8 @@ obj-$(CONFIG_ARM_S5PV210_CPUFREQ)	+= s5pv210-cpufreq.o
 obj-$(CONFIG_ARM_SA1100_CPUFREQ)        += sa1100-cpufreq.o
 obj-$(CONFIG_ARM_SA1110_CPUFREQ)        += sa1110-cpufreq.o
 obj-$(CONFIG_ARM_SPEAR_CPUFREQ)         += spear-cpufreq.o
-obj-$(CONFIG_ARM_TEGRA_CPUFREQ)         += tegra-cpufreq.o
+obj-$(CONFIG_ARM_TEGRA20_CPUFREQ)       += tegra20-cpufreq.o
+obj-$(CONFIG_ARM_TEGRA124_CPUFREQ)      += tegra124-cpufreq.o
 obj-$(CONFIG_ARM_VEXPRESS_SPC_CPUFREQ)  += vexpress-spc-cpufreq.o
 
 ##################################################################################
diff --git a/drivers/cpufreq/tegra124-cpufreq.c b/drivers/cpufreq/tegra124-cpufreq.c
new file mode 100644
index 000000000000..20bcceb58ccc
--- /dev/null
+++ b/drivers/cpufreq/tegra124-cpufreq.c
@@ -0,0 +1,214 @@
+/*
+ * Tegra 124 cpufreq driver
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+#define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/cpufreq-dt.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/regulator/consumer.h>
+#include <linux/types.h>
+
+struct tegra124_cpufreq_priv {
+        struct regulator *vdd_cpu_reg;
+        struct clk *cpu_clk;
+        struct clk *pllp_clk;
+        struct clk *pllx_clk;
+        struct clk *dfll_clk;
+        struct platform_device *cpufreq_dt_pdev;
+};
+
+static int tegra124_cpu_switch_to_dfll(struct tegra124_cpufreq_priv *priv)
+{
+        struct clk *orig_parent;
+        int ret;
+
+        ret = clk_set_rate(priv->dfll_clk, clk_get_rate(priv->cpu_clk));
+        if (ret)
+                return ret;
+
+        orig_parent = clk_get_parent(priv->cpu_clk);
+        clk_set_parent(priv->cpu_clk, priv->pllp_clk);
+
+        ret = clk_prepare_enable(priv->dfll_clk);
+        if (ret)
+                goto out;
+
+        clk_set_parent(priv->cpu_clk, priv->dfll_clk);
+
+        return 0;
+
+out:
+        clk_set_parent(priv->cpu_clk, orig_parent);
+
+        return ret;
+}
+
+static void tegra124_cpu_switch_to_pllx(struct tegra124_cpufreq_priv *priv)
+{
+        clk_set_parent(priv->cpu_clk, priv->pllp_clk);
+        clk_disable_unprepare(priv->dfll_clk);
+        regulator_sync_voltage(priv->vdd_cpu_reg);
+        clk_set_parent(priv->cpu_clk, priv->pllx_clk);
+}
+
+static struct cpufreq_dt_platform_data cpufreq_dt_pd = {
+        .independent_clocks = false,
+};
+
+static int tegra124_cpufreq_probe(struct platform_device *pdev)
+{
+        struct tegra124_cpufreq_priv *priv;
+        struct device_node *np;
+        struct device *cpu_dev;
+        struct platform_device_info cpufreq_dt_devinfo = {};
+        int ret;
+
+        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
+        cpu_dev = get_cpu_device(0);
+        if (!cpu_dev)
+                return -ENODEV;
+
+        np = of_cpu_device_node_get(0);
+        if (!np)
+                return -ENODEV;
+
+        priv->vdd_cpu_reg = regulator_get(cpu_dev, "vdd-cpu");
+        if (IS_ERR(priv->vdd_cpu_reg)) {
+                ret = PTR_ERR(priv->vdd_cpu_reg);
+                goto out_put_np;
+        }
+
+        priv->cpu_clk = of_clk_get_by_name(np, "cpu_g");
+        if (IS_ERR(priv->cpu_clk)) {
+                ret = PTR_ERR(priv->cpu_clk);
+                goto out_put_vdd_cpu_reg;
+        }
+
+        priv->dfll_clk = of_clk_get_by_name(np, "dfll");
+        if (IS_ERR(priv->dfll_clk)) {
+                ret = PTR_ERR(priv->dfll_clk);
+                goto out_put_cpu_clk;
+        }
+
+        priv->pllx_clk = of_clk_get_by_name(np, "pll_x");
+        if (IS_ERR(priv->pllx_clk)) {
+                ret = PTR_ERR(priv->pllx_clk);
+                goto out_put_dfll_clk;
+        }
+
+        priv->pllp_clk = of_clk_get_by_name(np, "pll_p");
+        if (IS_ERR(priv->pllp_clk)) {
+                ret = PTR_ERR(priv->pllp_clk);
+                goto out_put_pllx_clk;
+        }
+
+        ret = tegra124_cpu_switch_to_dfll(priv);
+        if (ret)
+                goto out_put_pllp_clk;
+
+        cpufreq_dt_devinfo.name = "cpufreq-dt";
+        cpufreq_dt_devinfo.parent = &pdev->dev;
+        cpufreq_dt_devinfo.data = &cpufreq_dt_pd;
+        cpufreq_dt_devinfo.size_data = sizeof(cpufreq_dt_pd);
+
+        priv->cpufreq_dt_pdev =
+                platform_device_register_full(&cpufreq_dt_devinfo);
+        if (IS_ERR(priv->cpufreq_dt_pdev)) {
+                ret = PTR_ERR(priv->cpufreq_dt_pdev);
+                goto out_switch_to_pllx;
+        }
+
+        platform_set_drvdata(pdev, priv);
+
+        return 0;
+
+out_switch_to_pllx:
+        tegra124_cpu_switch_to_pllx(priv);
+out_put_pllp_clk:
+        clk_put(priv->pllp_clk);
+out_put_pllx_clk:
+        clk_put(priv->pllx_clk);
+out_put_dfll_clk:
+        clk_put(priv->dfll_clk);
+out_put_cpu_clk:
+        clk_put(priv->cpu_clk);
+out_put_vdd_cpu_reg:
+        regulator_put(priv->vdd_cpu_reg);
+out_put_np:
+        of_node_put(np);
+
+        return ret;
+}
+
+static int tegra124_cpufreq_remove(struct platform_device *pdev)
+{
+        struct tegra124_cpufreq_priv *priv = platform_get_drvdata(pdev);
+
+        platform_device_unregister(priv->cpufreq_dt_pdev);
+        tegra124_cpu_switch_to_pllx(priv);
+
+        clk_put(priv->pllp_clk);
+        clk_put(priv->pllx_clk);
+        clk_put(priv->dfll_clk);
+        clk_put(priv->cpu_clk);
+        regulator_put(priv->vdd_cpu_reg);
+
+        return 0;
+}
+
+static struct platform_driver tegra124_cpufreq_platdrv = {
+        .driver.name    = "cpufreq-tegra124",
+        .probe          = tegra124_cpufreq_probe,
+        .remove         = tegra124_cpufreq_remove,
+};
+
+static int __init tegra_cpufreq_init(void)
+{
+        int ret;
+        struct platform_device *pdev;
+
+        if (!of_machine_is_compatible("nvidia,tegra124"))
+                return -ENODEV;
+
+        /*
+         * Platform driver+device required for handling EPROBE_DEFER with
+         * the regulator and the DFLL clock
+         */
+        ret = platform_driver_register(&tegra124_cpufreq_platdrv);
+        if (ret)
+                return ret;
+
+        pdev = platform_device_register_simple("cpufreq-tegra124", -1, NULL, 0);
+        if (IS_ERR(pdev)) {
+                platform_driver_unregister(&tegra124_cpufreq_platdrv);
+                return PTR_ERR(pdev);
+        }
+
+        return 0;
+}
+module_init(tegra_cpufreq_init);
+
+MODULE_AUTHOR("Tuomas Tynkkynen <ttynkkynen@nvidia.com>");
+MODULE_DESCRIPTION("cpufreq driver for NVIDIA Tegra124");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/cpufreq/tegra-cpufreq.c b/drivers/cpufreq/tegra20-cpufreq.c
index 8084c7f7e206..8084c7f7e206 100644
--- a/drivers/cpufreq/tegra-cpufreq.c
+++ b/drivers/cpufreq/tegra20-cpufreq.c