Re: [PATCH v10 09/24] coresight: etm3x: allow etm3x to be built as a module

From: Tingwei Zhang
Date: Sun Sep 13 2020 - 22:21:22 EST


On Sun, Sep 13, 2020 at 09:17:05PM +0800, Suzuki K Poulose wrote:
> On 08/21/2020 04:44 AM, Tingwei Zhang wrote:
> >From: Kim Phillips <kim.phillips@xxxxxxx>
> >
> >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@xxxxxxxxxx>
> >Cc: Leo Yan <leo.yan@xxxxxxxxxx>
> >Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> >Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> >Cc: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx>
> >Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> >Cc: Russell King <linux@xxxxxxxxxxxxxxx>
> >Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
> >Signed-off-by: Tingwei Zhang <tingwei@xxxxxxxxxxxxxx>
> >Reviewed-by: Mike Leach <mike.leach@xxxxxxxxxx>
>
>
> >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..ba9c86497acb 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;
> >+}
> >+
>
> Don't we need to fix the races like we did for ETMv4 ?
>
> Suzuki
>
Yes, we need that. Unfortunately, I don't have ETMv3 devie to verify the
change. Mathieu has been very kind to offer his help to take care of
ETMv3.

Thanks,
Tingwei
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