Re: [PATCH v8 24/24] coresight: allow the coresight core driver to be built as a module

Tingwei Zhang
2020-08-17T22:57:54Z

On Tue, Aug 18, 2020 at 01:47:22AM +0800, Mathieu Poirier wrote:
> On Fri, Aug 07, 2020 at 07:11:53PM +0800, Tingwei Zhang wrote:
> > Enhance coresight developer's efficiency to debug coresight drivers.
> > - 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 etm_perf
> > register/unregister function calls to the core init/exit
> > functions.
> > - 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>
> > ---
> > drivers/hwtracing/coresight/Kconfig | 5 ++-
> > drivers/hwtracing/coresight/Makefile | 5 ++-
> > .../{coresight.c => coresight-core.c} | 42 ++++++++++++++-----
> > .../hwtracing/coresight/coresight-etm-perf.c | 8 +++-
> > .../hwtracing/coresight/coresight-etm-perf.h | 3 ++
> > 5 files changed, 48 insertions(+), 15 deletions(-)
> > rename drivers/hwtracing/coresight/{coresight.c => coresight-core.c}
> (98%)
> >
> > diff --git a/drivers/hwtracing/coresight/Kconfig
> b/drivers/hwtracing/coresight/Kconfig
> > index dfe407cde262..c1198245461d 100644
> > --- a/drivers/hwtracing/coresight/Kconfig
> > +++ b/drivers/hwtracing/coresight/Kconfig
> > @@ -3,7 +3,7 @@
> > # Coresight configuration
> > #
> > menuconfig CORESIGHT
> > - bool "CoreSight Tracing Support"
> > + tristate "CoreSight Tracing Support"
> > depends on ARM || ARM64
> > depends on OF || ACPI
> > select ARM_AMBA
> > @@ -15,6 +15,9 @@ 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 0359d5a1588f..1b35b55bd420 100644
> > --- a/drivers/hwtracing/coresight/Makefile
> > +++ b/drivers/hwtracing/coresight/Makefile
> > @@ -2,8 +2,9 @@
> > #
> > # Makefile for CoreSight drivers.
> > #
> > -obj-$(CONFIG_CORESIGHT) += coresight.o coresight-etm-perf.o \
> > - coresight-platform.o coresight-sysfs.o
> > +obj-$(CONFIG_CORESIGHT) += coresight.o
> > +coresight-y := coresight-core.o coresight-etm-perf.o
> coresight-platform.o \
> > + coresight-sysfs.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
> > diff --git a/drivers/hwtracing/coresight/coresight.c
> b/drivers/hwtracing/coresight/coresight-core.c
> > similarity index 98%
> > rename from drivers/hwtracing/coresight/coresight.c
> > rename to drivers/hwtracing/coresight/coresight-core.c
> > index f9566d667261..045416ac962f 100644
> > --- a/drivers/hwtracing/coresight/coresight.c
> > +++ b/drivers/hwtracing/coresight/coresight-core.c
> > @@ -1462,16 +1462,6 @@ int coresight_timeout(void __iomem *addr, u32
> offset, int position, int value)
> > }
> > EXPORT_SYMBOL_GPL(coresight_timeout);
> >
> > -struct bus_type coresight_bustype = {
> > - .name = "coresight",
> > -};
> > -
> > -static int __init coresight_init(void)
> > -{
> > - return bus_register(&coresight_bustype);
> > -}
> > -postcore_initcall(coresight_init);
> > -
> > /*
> > * coresight_release_platform_data: Release references to the devices
> connected
> > * to the output port of this device.
> > @@ -1680,3 +1670,35 @@ char *coresight_alloc_device_name(struct
> coresight_dev_list *dict,
> > return name;
> > }
> > EXPORT_SYMBOL_GPL(coresight_alloc_device_name);
> > +
> > +struct bus_type coresight_bustype = {
> > + .name = "coresight",
> > +};
> > +
> > +static int __init coresight_init(void)
> > +{
> > + int ret;
> > +
> > + ret = bus_register(&coresight_bustype);
> > + if (ret)
> > + return ret;
> > +
> > + ret = etm_perf_init();
> > + if (ret)
> > + bus_unregister(&coresight_bustype);
> > +
> > + return ret;
> > +}
> > +
> > +static void __exit coresight_exit(void)
> > +{
> > + etm_perf_exit();
> > + bus_unregister(&coresight_bustype);
> > +}
> > +
> > +module_init(coresight_init);
> > +module_exit(coresight_exit);
> > +
> > +MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
>
> Pratik deserves credit too.
>
> With that:
>
> Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
>
> I am done reviewing this set.
>
> Thank you for the patience,
> Mathieu
>

Thanks for the review of this big patchset, Mathieu.
Sorry for some silly mistakes.

Thanks,
Tingwei

> > +MODULE_DESCRIPTION("Arm CoreSight tracer driver");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c
> b/drivers/hwtracing/coresight/coresight-etm-perf.c
> > index 3728c44e5763..668b3ff11576 100644
> > --- a/drivers/hwtracing/coresight/coresight-etm-perf.c
> > +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
> > @@ -591,7 +591,7 @@ void etm_perf_del_symlink_sink(struct
> coresight_device *csdev)
> > csdev->ea = NULL;
> > }
> >
> > -static int __init etm_perf_init(void)
> > +int __init etm_perf_init(void)
> > {
> > int ret;
> >
> > @@ -618,4 +618,8 @@ static int __init etm_perf_init(void)
> >
> > return ret;
> > }
> > -device_initcall(etm_perf_init);
> > +
> > +void __exit etm_perf_exit(void)
> > +{
> > + perf_pmu_unregister(&etm_pmu);
> > +}
> > diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h
> b/drivers/hwtracing/coresight/coresight-etm-perf.h
> > index 05f89723e282..3e4f2ad5e193 100644
> > --- a/drivers/hwtracing/coresight/coresight-etm-perf.h
> > +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h
> > @@ -82,4 +82,7 @@ static inline void *etm_perf_sink_config(struct
> perf_output_handle *handle)
> >
> > #endif /* CONFIG_CORESIGHT */
> >
> > +int __init etm_perf_init(void);
> > +void __exit etm_perf_exit(void);
> > +
> > #endif
> > --
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
> Forum,
> > a Linux Foundation Collaborative Project
> >