[PATCH 3/9] coresight-tpdm: Initialize DSB subunit configuration
Suzuki K Poulose
suzuki.poulose at arm.com
Wed Oct 26 07:18:47 PDT 2022
On 26/10/2022 09:10, Tao Zhang wrote:
> Hi Suzuki,
>
> 在 10/24/2022 6:02 PM, Suzuki K Poulose 写道:
>> Hi
>>
>> On 08/09/2022 09:44, Tao Zhang wrote:
>>> DSB subunit need to be configured in enablement and disablement.
>>> A struct that specifics associated to dsb dataset is needed. It
>>> saves the configuration and parameters of the dsb datasets. This
>>> change is to add this struct and initialize the configuration of
>>> DSB subunit.
>>>
>>> Signed-off-by: Tao Zhang <quic_taozha at quicinc.com>
>>> ---
>>> drivers/hwtracing/coresight/coresight-tpdm.c | 44
>>> ++++++++++++++++++++++++++--
>>> drivers/hwtracing/coresight/coresight-tpdm.h | 17 +++++++++++
>>> 2 files changed, 58 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c
>>> b/drivers/hwtracing/coresight/coresight-tpdm.c
>>> index 88df3e6..69ea453 100644
>>> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
>>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
>>> @@ -24,6 +24,22 @@ static void tpdm_enable_dsb(struct tpdm_drvdata
>>> *drvdata)
>>> {
>>> u32 val;
>>> + val = readl_relaxed(drvdata->base + TPDM_DSB_TIER);
>>> + /* Set trigger timestamp */
>>> + if (drvdata->dsb->trig_ts)
>>
>> What happens if this instance doesn't have a DSB set ? Have
>> you tested this on a system without the DSB ?
>>
> The function "tpdm_enable_dsb" will only be called when it is checked
> that the DSB dataset is present.
>
> And only the TPDM that supports the DSB dataset will have the DSB TIER
> register.
>
> If the TPDM doesn't support the DSB dataset, this instance should not be
> run. Otherwise, it will cause that the incorrect register is accessed.
Thanks, this is what happens when you send something that is not queued
anywhwere. Please provide a reference tree in the future, for ease of
reviewing such things
Suzuki
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