[PATCH v4 14/14] coresight: allow the coresight core driver to be built as a module
From: Kim Phillips
Date: Tue Jun 05 2018 - 17:07:56 EST
Allow to build coresight as a module. This enhances
coresight developer efficiency by allowing the development to
take place exclusively on the target, and without needing to
reboot in between changes.
- Kconfig becomes a tristate, to allow =m
- append -core to source file name to allow module to
be called coresight by the Makefile
- modules can have only one init/exit, so we add the core bus
register/unregister function calls to the etm_perf init/exit
functions, since coresight.c does not have etm_pmu defined.
- add a MODULE_DEVICE_TABLE for autoloading on boot
Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
---
drivers/hwtracing/coresight/Kconfig | 5 ++++-
drivers/hwtracing/coresight/Makefile | 7 +++++--
.../coresight/{coresight.c => coresight-core.c} | 6 ------
.../hwtracing/coresight/coresight-etm-perf.c | 17 ++++++++++++++++-
4 files changed, 25 insertions(+), 10 deletions(-)
rename drivers/hwtracing/coresight/{coresight.c => coresight-core.c} (99%)
diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 181a44ea2d61..c05b265f7731 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -2,7 +2,7 @@
# Coresight configuration
#
menuconfig CORESIGHT
- bool "CoreSight Tracing Support"
+ tristate "CoreSight Tracing Support"
select ARM_AMBA
select PERF_EVENTS
help
@@ -12,6 +12,9 @@ menuconfig CORESIGHT
specification and configure the right series of components when a
trace source gets enabled.
+ To compile this driver as a module, choose M here: the
+ module will be called coresight.
+
if CORESIGHT
config CORESIGHT_LINKS_AND_SINKS
tristate "CoreSight Link and Sink drivers"
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 45d7a0f34170..ed2d4bcb017b 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -2,8 +2,11 @@
#
# Makefile for CoreSight drivers.
#
-obj-$(CONFIG_CORESIGHT) += coresight.o coresight-etm-perf.o
-obj-$(CONFIG_OF) += of_coresight.o
+obj-$(CONFIG_CORESIGHT) += coresight.o
+coresight-objs := coresight-core.o coresight-etm-perf.o
+ifeq ($(CONFIG_OF), y)
+coresight-objs += of_coresight.o
+endif
obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o
coresight-tmc-objs := coresight-tmc-core.o coresight-tmc-etf.o \
coresight-tmc-etr.o
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight-core.c
similarity index 99%
rename from drivers/hwtracing/coresight/coresight.c
rename to drivers/hwtracing/coresight/coresight-core.c
index 1c941351f1d1..f96258de1e9b 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -948,12 +948,6 @@ struct bus_type coresight_bustype = {
.name = "coresight",
};
-static int __init coresight_init(void)
-{
- return bus_register(&coresight_bustype);
-}
-postcore_initcall(coresight_init);
-
struct coresight_device *coresight_register(struct coresight_desc *desc)
{
int i;
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 0fe7e43ea1c4..ceac9aee4a82 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -472,6 +472,10 @@ static int __init etm_perf_init(void)
{
int ret;
+ ret = bus_register(&coresight_bustype);
+ if (ret)
+ return ret;
+
etm_pmu.capabilities = PERF_PMU_CAP_EXCLUSIVE;
etm_pmu.attr_groups = etm_pmu_attr_groups;
@@ -494,4 +498,15 @@ static int __init etm_perf_init(void)
return ret;
}
-device_initcall(etm_perf_init);
+postcore_initcall(etm_perf_init);
+
+static void __exit etm_perf_exit(void)
+{
+ perf_pmu_unregister(&etm_pmu);
+ bus_unregister(&coresight_bustype);
+}
+module_exit(etm_perf_exit);
+
+MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Arm CoreSight tracer driver");
+MODULE_LICENSE("GPL v2");
--
2.17.0