Messages in this thread | | | Date | Thu, 2 Jun 2022 11:14:02 +0800 | Subject | Re: [PATCH v7 02/10] Coresight: Add coresight TPDM source driver | From | Jinlong Mao <> |
| |
On 6/1/2022 5:56 PM, Jinlong Mao wrote: > > On 6/1/2022 5:30 PM, Suzuki K Poulose wrote: >> On 01/06/2022 10:21, Jinlong Mao wrote: >>> Hi Suzuki, >>> >>> On 5/24/2022 3:00 PM, Jinlong Mao wrote: >>>> Hi Suzuki, >>>> >>>> Thank you for the review. >>>> >>>> On 5/23/2022 4:57 PM, Suzuki K Poulose wrote: >>>>> Hi >>>>> >>>>> On 09/05/2022 14:39, Mao Jinlong wrote: >>>>>> Add driver to support Coresight device TPDM (Trace, Profiling and >>>>>> Diagnostics Monitor). TPDM is a monitor to collect data from >>>>>> different datasets. This change is to add probe/enable/disable >>>>>> functions for tpdm source. >>>>>> >>>>>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com> >>>>>> Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com> >>>>>> --- >>>>>> drivers/hwtracing/coresight/Kconfig | 13 ++ >>>>>> drivers/hwtracing/coresight/Makefile | 1 + >>>>>> drivers/hwtracing/coresight/coresight-core.c | 5 +- >>>>>> drivers/hwtracing/coresight/coresight-tpdm.c | 146 >>>>>> +++++++++++++++++++ >>>>>> drivers/hwtracing/coresight/coresight-tpdm.h | 26 ++++ >>>>>> include/linux/coresight.h | 1 + >>>>>> 6 files changed, 191 insertions(+), 1 deletion(-) >>>>>> create mode 100644 drivers/hwtracing/coresight/coresight-tpdm.c >>>>>> create mode 100644 drivers/hwtracing/coresight/coresight-tpdm.h >>>>>> >>> >>>>>> +/** >>>>>> + * struct tpdm_drvdata - specifics associated to an TPDM component >>>>>> + * @base: memory mapped base address for this component. >>>>>> + * @dev: The device entity associated to this component. >>>>>> + * @csdev: component vitals needed by the framework. >>>>>> + * @lock: lock for the enable value. >>>>>> + * @enable: enable status of the component. >>>>>> + */ >>>>>> + >>>>>> +struct tpdm_drvdata { >>>>>> + void __iomem *base; >>>>>> + struct device *dev; >>>>>> + struct coresight_device *csdev; >>>>>> + struct mutex lock; >>>>> >>>>> Why mutex lock ? Couldn't this be a spinlock ? >>>> 1. There is no irq for TPDM >>>> 2. As there are 7 dataset types, there will be some FOR loop to >>>> configure >>>> tpdm registers which may cause some time. >> >> How long does it take to configure ? Is it too long enough to trigger >> RCU stalls ? as long as we don't do any sleeping/blocking operations >> we should be fine with a spinlock. >> >> Suzuki > > Let me check on internal device and get back to you. > > Thanks > Jinlong Mao
The time of configuring the registers doesn't reach RCU stall timeout value.
I will use spin_lock for both tpdm and tpda.
Thanks Jinlong Mao >> >>>> >>> I think we can use mutex lock here. Do you have any more comments >>> for this ? >> >>> >>> Thanks >>> Jinlong Mao >>>>> >>>>>> + bool enable; >>>>>> +}; >>>>>> + >>>>>> +#endif /* _CORESIGHT_CORESIGHT_TPDM_H */ >>>>>> diff --git a/include/linux/coresight.h b/include/linux/coresight.h >>>>>> index 247147c11231..a9efac55029d 100644 >>>>>> --- a/include/linux/coresight.h >>>>>> +++ b/include/linux/coresight.h >>>>>> @@ -61,6 +61,7 @@ enum coresight_dev_subtype_source { >>>>>> CORESIGHT_DEV_SUBTYPE_SOURCE_PROC, >>>>>> CORESIGHT_DEV_SUBTYPE_SOURCE_BUS, >>>>>> CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE, >>>>>> + CORESIGHT_DEV_SUBTYPE_SOURCE_DATA_ONLY, >>>>> >>>>> super minor nit: I find the choice of name a bit odd. >>>>> We could simply make it something like : >>>>> >>>>> CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS: >>>>> >>>>> Suzuki >>>> I will check and update. >>>>> >>>>>> }; >>>>>> enum coresight_dev_subtype_helper { >>>>> >>>>> _______________________________________________ >>>>> CoreSight mailing list -- coresight@lists.linaro.org >>>>> To unsubscribe send an email to coresight-leave@lists.linaro.org >>>> _______________________________________________ >>>> CoreSight mailing list -- coresight@lists.linaro.org >>>> To unsubscribe send an email to coresight-leave@lists.linaro.org >> >> _______________________________________________ >> CoreSight mailing list -- coresight@lists.linaro.org >> To unsubscribe send an email to coresight-leave@lists.linaro.org > _______________________________________________ > CoreSight mailing list -- coresight@lists.linaro.org > To unsubscribe send an email to coresight-leave@lists.linaro.org
| |