Hi Leonard,
On 2019-11-14 12:09, Leonard Crestez wrote:
Add initial support for dynamic frequency switching on pieces of the
imx
interconnect fabric.
All this driver does is set a clk rate based on an opp table, it does
not map register areas.
Is this working with mainline ATF or does it still need to be used with
your modified ATF code ?
Thanks
Angus
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
---
drivers/devfreq/Kconfig | 9 ++
drivers/devfreq/Makefile | 1 +
drivers/devfreq/imx-devfreq.c | 150 ++++++++++++++++++++++++++++++++++
3 files changed, 160 insertions(+)
create mode 100644 drivers/devfreq/imx-devfreq.c
diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 923a6132e741..fef5ce831e90 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -98,10 +98,19 @@ config ARM_IMX8M_DDRC_DEVFREQ
select DEVFREQ_GOV_USERSPACE
help
This adds the DEVFREQ driver for the i.MX8M DDR Controller. It
allows
adjusting DRAM frequency.
+config ARM_IMX_DEVFREQ
+ tristate "i.MX Generic DEVFREQ Driver"
+ depends on ARCH_MXC || COMPILE_TEST
+ select DEVFREQ_GOV_PASSIVE
+ select DEVFREQ_GOV_USERSPACE
+ help
+ This adds the generic DEVFREQ driver for i.MX interconnects. It
+ allows adjusting NIC/NOC frequency.
+
config ARM_TEGRA_DEVFREQ
tristate "NVIDIA Tegra30/114/124/210 DEVFREQ Driver"
depends on ARCH_TEGRA_3x_SOC || ARCH_TEGRA_114_SOC || \
ARCH_TEGRA_132_SOC || ARCH_TEGRA_124_SOC || \
ARCH_TEGRA_210_SOC || \
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 3eb4d5e6635c..61d0edee16f7 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -8,10 +8,11 @@ obj-$(CONFIG_DEVFREQ_GOV_USERSPACE) +=
governor_userspace.o
obj-$(CONFIG_DEVFREQ_GOV_PASSIVE) += governor_passive.o
# DEVFREQ Drivers
obj-$(CONFIG_ARM_EXYNOS_BUS_DEVFREQ) += exynos-bus.o
obj-$(CONFIG_ARM_IMX8M_DDRC_DEVFREQ) += imx8m-ddrc.o
+obj-$(CONFIG_ARM_IMX_DEVFREQ) += imx-devfreq.o
obj-$(CONFIG_ARM_RK3399_DMC_DEVFREQ) += rk3399_dmc.o
obj-$(CONFIG_ARM_TEGRA_DEVFREQ) += tegra30-devfreq.o
obj-$(CONFIG_ARM_TEGRA20_DEVFREQ) += tegra20-devfreq.o
# DEVFREQ Event Drivers
diff --git a/drivers/devfreq/imx-devfreq.c
b/drivers/devfreq/imx-devfreq.c
new file mode 100644
index 000000000000..620b344e87aa
--- /dev/null
+++ b/drivers/devfreq/imx-devfreq.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+struct imx_devfreq {
+ struct devfreq_dev_profile profile;
+ struct devfreq *devfreq;
+ struct clk *clk;
+ struct devfreq_passive_data passive_data;
+};
+
+static int imx_devfreq_target(struct device *dev,
+ unsigned long *freq, u32 flags)
+{
+ struct imx_devfreq *priv = dev_get_drvdata(dev);
+ struct dev_pm_opp *new_opp;
+ unsigned long new_freq;
+ int ret;
+
+ new_opp = devfreq_recommended_opp(dev, freq, flags);
+ if (IS_ERR(new_opp)) {
+ ret = PTR_ERR(new_opp);
+ dev_err(dev, "failed to get recommended opp: %d\n", ret);
+ return ret;
+ }
+ new_freq = dev_pm_opp_get_freq(new_opp);
+ dev_pm_opp_put(new_opp);
+
+ return clk_set_rate(priv->clk, new_freq);
+}
+
+static int imx_devfreq_get_cur_freq(struct device *dev, unsigned long
*freq)
+{
+ struct imx_devfreq *priv = dev_get_drvdata(dev);
+
+ *freq = clk_get_rate(priv->clk);
+
+ return 0;
+}
+
+static int imx_devfreq_get_dev_status(struct device *dev,
+ struct devfreq_dev_status *stat)
+{
+ struct imx_devfreq *priv = dev_get_drvdata(dev);
+
+ stat->busy_time = 0;
+ stat->total_time = 0;
+ stat->current_frequency = clk_get_rate(priv->clk);
+
+ return 0;
+}
+
+static void imx_devfreq_exit(struct device *dev)
+{
+ dev_pm_opp_of_remove_table(dev);
+}
+
+static int imx_devfreq_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct imx_devfreq *priv;
+ const char *gov = DEVFREQ_GOV_USERSPACE;
+ void *govdata = NULL;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->clk)) {
+ ret = PTR_ERR(priv->clk);
+ dev_err(dev, "failed to fetch clk: %d\n", ret);
+ return ret;
+ }
+ platform_set_drvdata(pdev, priv);
+
+ ret = dev_pm_opp_of_add_table(dev);
+ if (ret < 0) {
+ dev_err(dev, "failed to get OPP table\n");
+ return ret;
+ }
+
+ priv->profile.polling_ms = 1000;
+ priv->profile.target = imx_devfreq_target;
+ priv->profile.get_dev_status = imx_devfreq_get_dev_status;
+ priv->profile.exit = imx_devfreq_exit;
+ priv->profile.get_cur_freq = imx_devfreq_get_cur_freq;
+ priv->profile.initial_freq = clk_get_rate(priv->clk);
+
+ /* Handle passive devfreq parent link */
+ priv->passive_data.parent = devfreq_get_devfreq_by_phandle(dev, 0);
+ if (!IS_ERR(priv->passive_data.parent)) {
+ dev_info(dev, "setup passive link to %s\n",
+ dev_name(priv->passive_data.parent->dev.parent));
+ gov = DEVFREQ_GOV_PASSIVE;
+ govdata = &priv->passive_data;
+ } else if (priv->passive_data.parent != ERR_PTR(-ENODEV)) {
+ // -ENODEV means no parent: not an error.
+ ret = PTR_ERR(priv->passive_data.parent);
+ if (ret != -EPROBE_DEFER)
+ dev_warn(dev, "failed to get initialize passive parent: %d\n",
+ ret);
+ goto err;
+ }
+
+ priv->devfreq = devm_devfreq_add_device(dev, &priv->profile,
+ gov, govdata);
+ if (IS_ERR(priv->devfreq)) {
+ ret = PTR_ERR(priv->devfreq);
+ dev_err(dev, "failed to add devfreq device: %d\n", ret);
+ goto err;
+ }
+
+ return 0;
+
+err:
+ dev_pm_opp_of_remove_table(dev);
+ return ret;
+}
+
+static const struct of_device_id imx_devfreq_of_match[] = {
+ { .compatible = "fsl,imx8m-noc", },
+ { .compatible = "fsl,imx8m-nic", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, imx_devfreq_of_match);
+
+static struct platform_driver imx_devfreq_platdrv = {
+ .probe = imx_devfreq_probe,
+ .driver = {
+ .name = "imx-devfreq",
+ .of_match_table = of_match_ptr(imx_devfreq_of_match),
+ },
+};
+module_platform_driver(imx_devfreq_platdrv);
+
+MODULE_DESCRIPTION("Generic i.MX bus frequency driver");
+MODULE_AUTHOR("Leonard Crestez <leonard.crestez@xxxxxxx>");
+MODULE_LICENSE("GPL v2");
