diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig index 514a9b8086e3..40b7bd19d2ad 100644 --- a/drivers/hwtracing/coresight/Kconfig +++ b/drivers/hwtracing/coresight/Kconfig @@ -188,6 +188,14 @@ config CORESIGHT_CTI_INTEGRATION_REGS registers are not used in normal operation and can leave devices in an inconsistent state. +config CORESIGHT_DUMMY + tristate "Dummy driver support" + help + Enables support for dummy driver. Dummy driver can be used for + CoreSight sources/sinks that are owned and configured by some + other subsystem and use Linux drivers to configure rest of trace + path. + config CORESIGHT_TRBE tristate "Trace Buffer Extension (TRBE) driver" depends on ARM64 && CORESIGHT_SOURCE_ETM4X diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index b6c4a48140ec..0e722261b47e 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -27,3 +27,4 @@ obj-$(CONFIG_CORESIGHT_CTI) += coresight-cti.o obj-$(CONFIG_CORESIGHT_TRBE) += coresight-trbe.o coresight-cti-y := coresight-cti-core.o coresight-cti-platform.o \ coresight-cti-sysfs.o +obj-$(CONFIG_CORESIGHT_DUMMY) += coresight-dummy.o diff --git a/drivers/hwtracing/coresight/coresight-dummy.c b/drivers/hwtracing/coresight/coresight-dummy.c new file mode 100644 index 000000000000..5e73b506d4e3 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-dummy.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include +#include +#include +#include +#include +#include + +#define DUMMY_TRACE_ID_START 256 + +struct dummy_drvdata { + struct device *dev; + struct coresight_device *csdev; + int traceid; +}; + +DEFINE_CORESIGHT_DEVLIST(dummy_devs, "dummy"); + +static int dummy_source_enable(struct coresight_device *csdev, + struct perf_event *event, u32 mode) +{ + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + dev_info(drvdata->dev, "Dummy source enabled\n"); + + return 0; +} + +static void dummy_source_disable(struct coresight_device *csdev, + struct perf_event *event) +{ + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + dev_info(drvdata->dev, "Dummy source disabled\n"); +} + +static int dummy_sink_enable(struct coresight_device *csdev, u32 mode, + void *data) +{ + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + dev_info(drvdata->dev, "Dummy sink enabled\n"); + + return 0; +} + +static int dummy_sink_disable(struct coresight_device *csdev) +{ + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + dev_info(drvdata->dev, "Dummy sink disabled\n"); + + return 0; +} + +static int dummy_trace_id(struct coresight_device *csdev) +{ + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); + + return drvdata->traceid; +} + +static const struct coresight_ops_source dummy_source_ops = { + .trace_id = dummy_trace_id, + .enable = dummy_source_enable, + .disable = dummy_source_disable, +}; + +static const struct coresight_ops_sink dummy_sink_ops = { + .enable = dummy_sink_enable, + .disable = dummy_sink_disable, +}; + +static const struct coresight_ops dummy_cs_ops = { + .source_ops = &dummy_source_ops, + .sink_ops = &dummy_sink_ops, +}; + +static int dummy_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct coresight_platform_data *pdata; + struct dummy_drvdata *drvdata; + struct coresight_desc desc = { 0 }; + static int traceid = DUMMY_TRACE_ID_START; + + desc.name = coresight_alloc_device_name(&dummy_devs, dev); + if (!desc.name) + return -ENOMEM; + pdata = coresight_get_platform_data(dev); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + pdev->dev.platform_data = pdata; + + drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); + if (!drvdata) + return -ENOMEM; + + drvdata->dev = &pdev->dev; + platform_set_drvdata(pdev, drvdata); + + drvdata->traceid = traceid++; + + if (of_property_read_bool(pdev->dev.of_node, "qcom,dummy-source")) { + desc.type = CORESIGHT_DEV_TYPE_SOURCE; + desc.subtype.source_subtype = + CORESIGHT_DEV_SUBTYPE_SOURCE_PROC; + } else if (of_property_read_bool(pdev->dev.of_node, + "qcom,dummy-sink")) { + desc.type = CORESIGHT_DEV_TYPE_SINK; + desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER; + } else { + dev_info(dev, "Device type not set\n"); + return -EINVAL; + } + + desc.ops = &dummy_cs_ops; + desc.pdata = pdev->dev.platform_data; + desc.dev = &pdev->dev; + drvdata->csdev = coresight_register(&desc); + if (IS_ERR(drvdata->csdev)) + return PTR_ERR(drvdata->csdev); + + pm_runtime_enable(dev); + dev_info(dev, "Dummy device initialized\n"); + + return 0; +} + +static int dummy_remove(struct platform_device *pdev) +{ + struct dummy_drvdata *drvdata = platform_get_drvdata(pdev); + struct device *dev = &pdev->dev; + + pm_runtime_disable(dev); + coresight_unregister(drvdata->csdev); + return 0; +} + +static const struct of_device_id dummy_match[] = { + {.compatible = "qcom,coresight-dummy"}, + {}, +}; + +static struct platform_driver dummy_driver = { + .probe = dummy_probe, + .remove = dummy_remove, + .driver = { + .name = "coresight-dummy", + .of_match_table = dummy_match, + }, +}; + +int __init dummy_init(void) +{ + return platform_driver_register(&dummy_driver); +} +module_init(dummy_init); + +void __exit dummy_exit(void) +{ + platform_driver_unregister(&dummy_driver); +} +module_exit(dummy_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("CoreSight dummy source driver");