[PATCH v8 09/24] coresight: etm3x: allow etm3x to be built as a module

Tingwei Zhang
2020-08-07T11:15:32Z

From: Kim Phillips <kim.phillips@arm.com>

Allow to build coresight-etm3x as a module, for ease of development.

- Kconfig becomes a tristate, to allow =m
- append -core to source file name to allow module to
be called coresight-etm3x by the Makefile
- add an etm_remove function, for module unload
- add a MODULE_DEVICE_TABLE for autoloading on boot

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
---
drivers/hwtracing/coresight/Kconfig | 5 +++-
drivers/hwtracing/coresight/Makefile | 3 ++-
...resight-etm3x.c => coresight-etm3x-core.c} | 27 ++++++++++++++++++-
3 files changed, 32 insertions(+), 3 deletions(-)
rename drivers/hwtracing/coresight/{coresight-etm3x.c => coresight-etm3x-core.c} (97%)

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 6433f835fc97..8fd9fd139cf3 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -65,7 +65,7 @@ config CORESIGHT_SINK_ETBV10
special enhancement or added features.

config CORESIGHT_SOURCE_ETM3X
- bool "CoreSight Embedded Trace Macrocell 3.x driver"
+ tristate "CoreSight Embedded Trace Macrocell 3.x driver"
depends on !ARM64
select CORESIGHT_LINKS_AND_SINKS
help
@@ -74,6 +74,9 @@ config CORESIGHT_SOURCE_ETM3X
This is primarily useful for instruction level tracing. Depending
the ETM version data tracing may also be available.

+ To compile this driver as a module, choose M here: the
+ module will be called coresight-etm3x.
+
config CORESIGHT_SOURCE_ETM4X
bool "CoreSight Embedded Trace Macrocell 4.x driver"
depends on ARM64
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 19497d1d92bf..d619cfd0abd8 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -11,7 +11,8 @@ obj-$(CONFIG_CORESIGHT_SINK_TPIU) += coresight-tpiu.o
obj-$(CONFIG_CORESIGHT_SINK_ETBV10) += coresight-etb10.o
obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) += coresight-funnel.o \
coresight-replicator.o
-obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm-cp14.o \
+obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o
+coresight-etm3x-y := coresight-etm3x-core.o coresight-etm-cp14.o \
coresight-etm3x-sysfs.o
obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \
coresight-etm4x-sysfs.o
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
similarity index 97%
rename from drivers/hwtracing/coresight/coresight-etm3x.c
rename to drivers/hwtracing/coresight/coresight-etm3x-core.c
index bf22dcfd3327..82b333c40006 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -895,6 +895,23 @@ static int etm_probe(struct amba_device *adev, const struct amba_id *id)
return ret;
}

+static int __exit etm_remove(struct amba_device *adev)
+{
+ struct etm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
+
+ etm_perf_symlink(drvdata->csdev, false);
+
+ if (--etm_count == 0) {
+ cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
+ if (hp_online)
+ cpuhp_remove_state_nocalls(hp_online);
+ }
+
+ coresight_unregister(drvdata->csdev);
+
+ return 0;
+}
+
#ifdef CONFIG_PM
static int etm_runtime_suspend(struct device *dev)
{
@@ -937,6 +954,8 @@ static const struct amba_id etm_ids[] = {
{ 0, 0},
};

+MODULE_DEVICE_TABLE(amba, etm_ids);
+
static struct amba_driver etm_driver = {
.drv = {
.name = "coresight-etm3x",
@@ -945,6 +964,12 @@ static struct amba_driver etm_driver = {
.suppress_bind_attrs = true,
},
.probe = etm_probe,
+ .remove = etm_remove,
.id_table = etm_ids,
};
-builtin_amba_driver(etm_driver);
+module_amba_driver(etm_driver);
+
+MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
+MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
+MODULE_DESCRIPTION("Arm CoreSight Program Flow Trace driver");
+MODULE_LICENSE("GPL v2");
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project