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

[Mathieu Poirier]

On Fri, Aug 07, 2020 at 07:11:42PM +0800, Tingwei Zhang wrote:
> From: Kim Phillips <kim.phillips at 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 at linaro.org>
> Cc: Leo Yan <leo.yan at linaro.org>
> Cc: Alexander Shishkin <alexander.shishkin at linux.intel.com>
> Cc: Randy Dunlap <rdunlap at infradead.org>
> Cc: Suzuki K Poulose <Suzuki.Poulose at arm.com>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Cc: Russell King <linux at armlinux.org.uk>
> Signed-off-by: Kim Phillips <kim.phillips at arm.com>
> Signed-off-by: Tingwei Zhang <tingwei at codeaurora.org>
> Tested-by: Mike Leach <mike.leach at linaro.org>
> Reviewed-by: Suzuki K Poulose <suzuki.poulose at arm.com>

For patches 11, 12 and 13:

Reviewed-by: Mathieu Poirier <mathieu.poirier at 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 at 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
>