pmdomain: Add test driver for power management

Extended with debugfs for performance states.
Extended to deal with OPP and multiple PM domains attaching.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

2 files changed, 294 insertions, 0 deletions

diff --git a/drivers/pmdomain/Makefile b/drivers/pmdomain/Makefile
index a68ece2f4c68..81ef64d277e1 100644
--- a/drivers/pmdomain/Makefile
+++ b/drivers/pmdomain/Makefile
@@ -17,3 +17,4 @@ obj-y					+= tegra/
 obj-y					+= ti/
 obj-y					+= xilinx/
 obj-y					+= core.o governor.o
+obj-y					+= rpm_test.o
diff --git a/drivers/pmdomain/rpm_test.c b/drivers/pmdomain/rpm_test.c
new file mode 100644
index 000000000000..c65eec9969c2
--- /dev/null
+++ b/drivers/pmdomain/rpm_test.c
@@ -0,0 +1,293 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Linaro Ltd
+ *
+ * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/delay.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/printk.h>
+#include <linux/io.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_opp.h>
+#include <linux/pm_qos.h>
+
+struct rpm_test_dev {
+	struct device *dev;
+	/* add more if needed */
+	int opp_token;
+	struct dev_pm_domain_list *pds;
+	struct dentry *debugfs_root;
+	u32 perf_state;
+};
+
+static const char *domain_names6[] = { "perf0", "perf1", NULL };
+
+static int rpm_test_perf_get(void *data, u64 *val)
+{
+	struct rpm_test_dev *rdev = data;
+
+	*val = rdev->perf_state;
+
+	return 0;
+}
+
+static int rpm_test_perf_set(void *data, u64 val)
+{
+	struct rpm_test_dev *rdev = data;
+	int ret;
+
+	ret = dev_pm_domain_set_performance_state(rdev->dev, val);
+	if (ret)
+		return ret;
+
+	rdev->perf_state = val;
+	return 0;
+}
+
+DEFINE_DEBUGFS_ATTRIBUTE(rpm_test_perf_ops, rpm_test_perf_get,
+			 rpm_test_perf_set, "%llu\n");
+
+static int rpm_test_probe(struct platform_device *pdev)
+{
+	struct rpm_test_dev *rdev;
+	struct dev_pm_opp *opp;
+	int ret;
+
+	dev_info(&pdev->dev, "%s\n", __func__);
+
+	rdev = devm_kzalloc(&pdev->dev,	sizeof(*rdev), GFP_KERNEL);
+	if (!rdev)
+		return -ENOMEM;
+
+	/* SCMI perf */
+	if (strcmp(dev_name(&pdev->dev), "rpm_test3") == 0) {
+		opp = dev_pm_opp_find_level_exact(&pdev->dev, 450000);
+		if (IS_ERR(opp))
+			dev_info(&pdev->dev, "OPP not found\n");
+		else
+			dev_pm_opp_set_opp(&pdev->dev, opp);
+	}
+
+	/* SCMI perf */
+	if (strcmp(dev_name(&pdev->dev), "rpm_test4") == 0) {
+		opp = dev_pm_opp_find_level_exact(&pdev->dev, 600000);
+		if (IS_ERR(opp))
+			dev_info(&pdev->dev, "OPP not found\n");
+		else
+			dev_pm_opp_set_opp(&pdev->dev, opp);
+	}
+
+	/* Single PM domain - OPP */
+	if (strcmp(dev_name(&pdev->dev), "rpm_test5") == 0) {
+		/*
+		 * Calling devm_pm_opp_of_add_table() twice works fine. Cleanup?
+		 * _read_opp_key() fails if the primary opp-node lacks any of
+		 * opp-level, opp-hz, opp-peak-kBps/opp-avg-kBps.
+		 * Get lazy link WARN when opp-level is both in primary node and
+		 * in the required-opps node. Needs to be fixed!
+		 */
+		ret = devm_pm_opp_of_add_table(&pdev->dev);
+		if (ret)
+			dev_info(&pdev->dev, "Unable to add OPP table %d\n", ret);
+
+		/*
+		 * Works when level is located in the required-opps and no level
+		 * in the primary node. If no required-opps but level in primary
+		 * node, then the level will set be, which may not be supported
+		 * by the genpd. The latter is still useful when the genpd has
+		 * created the OPPs dynamically via GENPD_FLAG_OPP_TABLE_FW.
+		 */
+//		opp = dev_pm_opp_find_level_exact(&pdev->dev, 100);
+
+		/*
+		 * Works when opp-hz is in the primary opp-node and level in the
+		 * required-opps for the single PM domain case.
+		 * Is this true for the multi case too? See rpm_test6.
+		 */
+		opp = dev_pm_opp_find_freq_exact(&pdev->dev, 133, true);
+		if (IS_ERR(opp))
+			dev_info(&pdev->dev, "OPP not found\n");
+		else
+			dev_pm_opp_set_opp(&pdev->dev, opp);
+
+		/*
+		 * Q: If there is no rate, level or bandwidth to specify for an
+		 * OPP, but only a required-opps - should we allow a "label"
+		 * to be used instead?
+		 */
+	}
+
+	/* Multi PM domain - OPP-legacy. */
+	if (strcmp(dev_name(&pdev->dev), "rpm_test6") == 0) {
+		struct device **virt_devs = NULL;
+		struct dev_pm_opp_config config = {
+			.genpd_names = domain_names6,
+			//.virt_devs = NULL, //NULL means no assignment is done
+			.virt_devs = &virt_devs,
+		};
+
+		ret = dev_pm_opp_set_config(&pdev->dev, &config);
+		if (ret < 0) {
+			dev_info(&pdev->dev, "Unable to attach and set OPP config %d\n", ret);
+			goto out;
+		}
+
+		rdev->opp_token = ret;
+
+		ret = devm_pm_opp_of_add_table(&pdev->dev);
+		if (ret)
+			dev_info(&pdev->dev, "Unable to add OPP table %d\n", ret);
+
+		ret = dev_pm_opp_get_opp_count(&pdev->dev);
+		dev_info(&pdev->dev, "Num OPP %d\n", ret);
+
+		/*
+		 * Finding the level from one of the required-opps doesn't work,
+		 * which works fine for the single PM domain case.
+		 */
+		//opp = dev_pm_opp_find_level_exact(&pdev->dev, 100);
+
+		/*
+		 * Finding the opp from a primary node specifying the opp-hz
+		 * works.
+		 */
+		opp = dev_pm_opp_find_freq_exact(&pdev->dev, 266, true);
+		if (IS_ERR(opp))
+			dev_info(&pdev->dev, "OPP not found\n");
+		else
+			dev_pm_opp_set_opp(&pdev->dev, opp);
+	}
+
+	/* Multi PM domain in DT - no perf/OPP. */
+	if (strcmp(dev_name(&pdev->dev), "rpm_test8") == 0) {
+		//ret = dev_pm_domain_attach_list(&pdev->dev, &attach_data8,
+		ret = dev_pm_domain_attach_list(&pdev->dev, NULL,
+						&rdev->pds);
+		dev_info(&pdev->dev, "ADDED multiple PM domains ret=%d\n", ret);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* Debugfs for performance states. */
+	rdev->debugfs_root = debugfs_create_dir(dev_name(&pdev->dev), NULL);
+	debugfs_create_file_unsafe("perf_state", S_IRUSR | S_IWUSR,
+				   rdev->debugfs_root, rdev,
+				   &rpm_test_perf_ops);
+
+	/*
+	 * NEXT STEPS:
+	 * Single PD with SCMI-perf: Call devm_pm_opp_of_add_table() even if it
+	 * isn'needed?
+	 * Multi PD with one scmi-perf and one scmi-power: How can we set an OPP
+	 * for the corresponding virtual device to scmi-perf, when operating on
+	 * &pdev->dev? Maybe instead of calling dev_pm_opp_set_config() with
+	 * genpd-names, use it to set the required/virt-devs for the OPP table?
+	 */
+out:
+
+	rdev->dev = &pdev->dev;
+	platform_set_drvdata(pdev, rdev);
+
+	pm_runtime_get_noresume(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, 100);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	pm_runtime_mark_last_busy(&pdev->dev);
+	pm_runtime_put(&pdev->dev);
+
+	dev_info(&pdev->dev, "%s - DONE\n", __func__);
+	return 0;
+}
+
+static int rpm_test_remove(struct platform_device *pdev)
+{
+	struct rpm_test_dev *rdev = platform_get_drvdata(pdev);
+
+	pm_runtime_get_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
+
+	dev_pm_domain_detach_list(rdev->pds);
+	debugfs_remove_recursive(rdev->debugfs_root);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int rpm_test_suspend(struct device *dev)
+{
+	int ret;
+
+	dev_info(dev, "%s\n", __func__);
+	pm_runtime_resume(dev);
+	ret = pm_runtime_force_suspend(dev);
+	dev_info(dev, "%s ret=%d\n", __func__, ret);
+
+	return ret;
+}
+
+static int rpm_test_resume(struct device *dev)
+{
+	int ret;
+
+	dev_info(dev, "%s\n", __func__);
+	ret = pm_runtime_force_resume(dev);
+	dev_info(dev, "%s ret=%d\n", __func__, ret);
+
+	return ret;
+}
+#endif
+
+#ifdef CONFIG_PM
+static int rpm_test_runtime_suspend(struct device *dev)
+{
+	dev_info(dev, "%s\n", __func__);
+	return 0;
+}
+
+static int rpm_test_runtime_resume(struct device *dev)
+{
+	dev_info(dev, "%s\n", __func__);
+	return 0;
+}
+#endif
+
+static const struct of_device_id rpm_test_ids[] = {
+	{
+		.compatible = "test,runtime-pm-test",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, rpm_test_ids);
+
+static const struct dev_pm_ops rpm_test_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(rpm_test_suspend, rpm_test_resume)
+	SET_RUNTIME_PM_OPS(rpm_test_runtime_suspend,
+			rpm_test_runtime_resume,
+			NULL)
+};
+
+static struct platform_driver rpm_test_driver = {
+	.probe = rpm_test_probe,
+	.remove = rpm_test_remove,
+	.driver = {
+		.name = "rpm-test-drv",
+		.pm = &rpm_test_dev_pm_ops,
+		.of_match_table = rpm_test_ids,
+	},
+};
+
+module_platform_driver(rpm_test_driver);
+MODULE_LICENSE("GPL v2");