An example of creating a loadable module to add CoreSight configurations into a system.
In the Kernel samples/coresight directory.
Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- MAINTAINERS | 1 + samples/Kconfig | 9 +++ samples/Makefile | 1 + samples/coresight/Makefile | 4 ++ samples/coresight/coresight-cfg-sample.c | 73 ++++++++++++++++++++++++ 5 files changed, 88 insertions(+) create mode 100644 samples/coresight/Makefile create mode 100644 samples/coresight/coresight-cfg-sample.c
diff --git a/MAINTAINERS b/MAINTAINERS index eeb4c70b3d5b..73437065e806 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1855,6 +1855,7 @@ F: Documentation/trace/coresight/* F: drivers/hwtracing/coresight/* F: include/dt-bindings/arm/coresight-cti-dt.h F: include/linux/coresight* +F: samples/coresight/* F: tools/perf/arch/arm/util/auxtrace.c F: tools/perf/arch/arm/util/cs-etm.c F: tools/perf/arch/arm/util/cs-etm.h diff --git a/samples/Kconfig b/samples/Kconfig index b0503ef058d3..ccd9596c951b 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -223,4 +223,13 @@ config SAMPLE_WATCH_QUEUE Build example userspace program to use the new mount_notify(), sb_notify() syscalls and the KEYCTL_WATCH_KEY keyctl() function.
+config SAMPLE_CORESIGHT_SYSCFG + tristate "Build example loadable module for CoreSight config" + depends on CORESIGHT && m + help + Build an example loadable module that adds new CoreSight features + and configuration using the CoreSight system configuration API. + This demonstrates how a user may create their own CoreSight + configurations and easily load them into the system at runtime. + endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index 087e0988ccc5..6c96297001a8 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -30,3 +30,4 @@ obj-$(CONFIG_SAMPLE_INTEL_MEI) += mei/ subdir-$(CONFIG_SAMPLE_WATCHDOG) += watchdog subdir-$(CONFIG_SAMPLE_WATCH_QUEUE) += watch_queue obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak/ +obj-$(CONFIG_SAMPLE_CORESIGHT_SYSCFG) += coresight/ diff --git a/samples/coresight/Makefile b/samples/coresight/Makefile new file mode 100644 index 000000000000..b3fce4af2347 --- /dev/null +++ b/samples/coresight/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only + +obj-$(CONFIG_SAMPLE_CORESIGHT_SYSCFG) += coresight-cfg-sample.o +ccflags-y += -I$(srctree)/drivers/hwtracing/coresight diff --git a/samples/coresight/coresight-cfg-sample.c b/samples/coresight/coresight-cfg-sample.c new file mode 100644 index 000000000000..25485c80b5e3 --- /dev/null +++ b/samples/coresight/coresight-cfg-sample.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright(C) 2020 Linaro Limited. All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include "coresight-config.h" +#include "coresight-syscfg.h" + +/* create an alternate autofdo configuration */ + +/* we will provide 4 sets of preset parameter values */ +#define AFDO2_NR_PRESETS 4 +/* the total number of parameters in used features - strobing has 2 */ +#define AFDO2_NR_PARAM_SUM 2 + +static const char *afdo2_ref_names[] = { + "strobing", +}; + +/* + * set of presets leaves strobing window constant while varying period to allow + * experimentation with mark / space ratios for various workloads + */ +static u64 afdo2_presets[AFDO2_NR_PRESETS][AFDO2_NR_PARAM_SUM] = { + { 1000, 100 }, + { 1000, 1000 }, + { 1000, 5000 }, + { 1000, 10000 }, +}; + +struct cscfg_config_desc afdo2 = { + .name = "autofdo2", + .description = "Setup ETMs with strobing for autofdo\n" + "Supplied presets allow experimentation with mark-space ratio for various loads\n", + .nr_feat_refs = ARRAY_SIZE(afdo2_ref_names), + .feat_ref_names = afdo2_ref_names, + .nr_presets = AFDO2_NR_PRESETS, + .nr_total_params = AFDO2_NR_PARAM_SUM, + .presets = &afdo2_presets[0][0], +}; + +static struct cscfg_feature_desc *sample_feats[] = { + NULL +}; + +static struct cscfg_config_desc *sample_cfgs[] = { + &afdo2, + NULL +}; + +static struct cscfg_load_owner_info mod_owner = { + .type = CSCFG_OWNER_MODULE, + .owner_handle = THIS_MODULE, +}; + +/* module init and exit - just load and unload configs */ +static int __init cscfg_sample_init(void) +{ + return cscfg_load_config_sets(sample_cfgs, sample_feats, &mod_owner); +} + +static void __exit cscfg_sample_exit(void) +{ + cscfg_unload_config_sets(&mod_owner); +} + +module_init(cscfg_sample_init); +module_exit(cscfg_sample_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Mike Leach mike.leach@linaro.org"); +MODULE_DESCRIPTION("CoreSight Syscfg Example");