Re: [PATCH v7 02/10] Coresight: Add coresight TPDM source driver
From: Jinlong Mao <hidden>
Date: 2022-06-02 03:14:14
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On 6/1/2022 5:56 PM, Jinlong Mao wrote:
On 6/1/2022 5:30 PM, Suzuki K Poulose wrote:quoted
On 01/06/2022 10:21, Jinlong Mao wrote:quoted
Hi Suzuki, On 5/24/2022 3:00 PM, Jinlong Mao wrote:quoted
Hi Suzuki, Thank you for the review. On 5/23/2022 4:57 PM, Suzuki K Poulose wrote:quoted
Hi On 09/05/2022 14:39, Mao Jinlong wrote:quoted
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 <redacted> Signed-off-by: Mao Jinlong <redacted> --- 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.hquoted
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+/** + * 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. SuzukiLet 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
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I think we can use mutex lock here. Do you have any more comments for this ?quoted
Thanks Jinlong Maoquoted
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+ 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: SuzukiI will check and update.quoted
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}; 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
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