Re: [PATCH v8 13/24] coresight: tmc: allow tmc to be built as a module

Mathieu Poirier
2020-08-13T20:38:14Z

On Fri, Aug 07, 2020 at 07:11:42PM +0800, Tingwei Zhang wrote:
> 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>

For patches 11, 12 and 13:

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} | 24 ++++++++++++++++++-
> 3 files changed, 31 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 271dc255454f..f2a568b969c4 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 7040d583bed9..f46852489adf 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc.c
> +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
> @@ -561,6 +561,21 @@ 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 */
> @@ -572,6 +587,8 @@ 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",
> @@ -580,6 +597,11 @@ 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");
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project