[PATCH v11 13/24] coresight: tmc: allow tmc to be built as a module

Tingwei Zhang
2020-09-15T10:43:39Z

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

Allow to build coresight-tmc 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-tmc by the Makefile
- add an tmc_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>
Tested-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
drivers/hwtracing/coresight/Kconfig | 6 ++++-
drivers/hwtracing/coresight/Makefile | 6 ++---
.../{coresight-tmc.c => coresight-tmc-core.c} | 25 ++++++++++++++++++-
3 files changed, 32 insertions(+), 5 deletions(-)
rename drivers/hwtracing/coresight/{coresight-tmc.c => coresight-tmc-core.c} (95%)

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 8fd9887fb03b..fc48ae086746 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -25,7 +25,8 @@ config CORESIGHT_LINKS_AND_SINKS
entity at run time to form a complete trace path.

config CORESIGHT_LINK_AND_SINK_TMC
- bool "Coresight generic TMC driver"
+ tristate "Coresight generic TMC driver"
+
depends on CORESIGHT_LINKS_AND_SINKS
help
This enables support for the Trace Memory Controller driver.
@@ -34,6 +35,9 @@ config CORESIGHT_LINK_AND_SINK_TMC
complies with the generic implementation of the component without
special enhancement or added features.

+ To compile this driver as a module, choose M here: the
+ module will be called coresight-tmc.
+
config CORESIGHT_CATU
bool "Coresight Address Translation Unit (CATU) driver"
depends on CORESIGHT_LINK_AND_SINK_TMC
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 3f2b057443fb..3dbd49a060dd 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -4,9 +4,9 @@
#
obj-$(CONFIG_CORESIGHT) += coresight.o coresight-etm-perf.o \
coresight-platform.o coresight-sysfs.o
-obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o \
- coresight-tmc-etf.o \
- coresight-tmc-etr.o
+obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o
+coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \
+ coresight-tmc-etr.o
obj-$(CONFIG_CORESIGHT_SINK_TPIU) += coresight-tpiu.o
obj-$(CONFIG_CORESIGHT_SINK_ETBV10) += coresight-etb10.o
obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) += coresight-funnel.o \
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
similarity index 95%
rename from drivers/hwtracing/coresight/coresight-tmc.c
rename to drivers/hwtracing/coresight/coresight-tmc-core.c
index 9ca3aaafcfbc..5653e0945c74 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -559,6 +559,21 @@ static void tmc_shutdown(struct amba_device *adev)
spin_unlock_irqrestore(&drvdata->spinlock, flags);
}

+static int __exit tmc_remove(struct amba_device *adev)
+{
+ struct tmc_drvdata *drvdata = dev_get_drvdata(&adev->dev);
+
+ /*
+ * Since misc_open() holds a refcount on the f_ops, which is
+ * etb fops in this case, device is there until last file
+ * handler to this device is closed.
+ */
+ misc_deregister(&drvdata->miscdev);
+ coresight_unregister(drvdata->csdev);
+
+ return 0;
+}
+
static const struct amba_id tmc_ids[] = {
CS_AMBA_ID(0x000bb961),
/* Coresight SoC 600 TMC-ETR/ETS */
@@ -570,6 +585,8 @@ static const struct amba_id tmc_ids[] = {
{ 0, 0},
};

+MODULE_DEVICE_TABLE(amba, tmc_ids);
+
static struct amba_driver tmc_driver = {
.drv = {
.name = "coresight-tmc",
@@ -578,6 +595,12 @@ static struct amba_driver tmc_driver = {
},
.probe = tmc_probe,
.shutdown = tmc_shutdown,
+ .remove = tmc_remove,
.id_table = tmc_ids,
};
-builtin_amba_driver(tmc_driver);
+
+module_amba_driver(tmc_driver);
+
+MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
+MODULE_DESCRIPTION("Arm CoreSight Trace Memory Controller driver");
+MODULE_LICENSE("GPL v2");