* [PATCH] coresight: replicator: Reset replicator if context is lost
@ 2020-05-11 8:34 Sai Prakash Ranjan
2020-05-11 16:19 ` Mathieu Poirier
0 siblings, 1 reply; 3+ messages in thread
From: Sai Prakash Ranjan @ 2020-05-11 8:34 UTC (permalink / raw)
To: Mathieu Poirier, Suzuki K Poulose, Mike Leach
Cc: Stephen Boyd, linux-kernel, linux-arm-msm, linux-arm-kernel,
coresight, Sai Prakash Ranjan
On some QCOM SoCs, replicators in Always-On domain loses its
context as soon as the clock is disabled. Currently as a part
of pm_runtime workqueue, clock is disabled after the replicator
is initialized by amba_pm_runtime_suspend assuming that context
is not lost which is not true for replicators with such
limitations. Hence check the replicator idfilter registers
in dynamic_replicator_enable() and reset again.
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
---
More info here - https://lore.kernel.org/patchwork/patch/1231182/
---
drivers/hwtracing/coresight/coresight-replicator.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
index e7dc1c31d20d..11df63f51071 100644
--- a/drivers/hwtracing/coresight/coresight-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-replicator.c
@@ -68,6 +68,17 @@ static int dynamic_replicator_enable(struct replicator_drvdata *drvdata,
int rc = 0;
u32 reg;
+ /*
+ * On some QCOM SoCs with replicators in Always-On domain, disabling
+ * clock will result in replicator losing its context. Currently
+ * as a part of pm_runtime workqueue, amba_pm_runtime_suspend disables
+ * clock assuming the context is not lost which is not true for cases
+ * with hardware limitations as the above.
+ */
+ if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0) &&
+ (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0))
+ dynamic_replicator_reset(drvdata);
+
switch (outport) {
case 0:
reg = REPLICATOR_IDFILTER0;
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] coresight: replicator: Reset replicator if context is lost
2020-05-11 8:34 [PATCH] coresight: replicator: Reset replicator if context is lost Sai Prakash Ranjan
@ 2020-05-11 16:19 ` Mathieu Poirier
2020-05-11 16:26 ` Sai Prakash Ranjan
0 siblings, 1 reply; 3+ messages in thread
From: Mathieu Poirier @ 2020-05-11 16:19 UTC (permalink / raw)
To: Sai Prakash Ranjan
Cc: Suzuki K Poulose, Mike Leach, linux-arm-msm, Coresight ML,
Linux Kernel Mailing List, Stephen Boyd, linux-arm-kernel
Hi Sai,
On Mon, 11 May 2020 at 02:34, Sai Prakash Ranjan
<saiprakash.ranjan@codeaurora.org> wrote:
>
> On some QCOM SoCs, replicators in Always-On domain loses its
> context as soon as the clock is disabled. Currently as a part
> of pm_runtime workqueue, clock is disabled after the replicator
> is initialized by amba_pm_runtime_suspend assuming that context
> is not lost which is not true for replicators with such
> limitations. Hence check the replicator idfilter registers
> in dynamic_replicator_enable() and reset again.
>
> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
> ---
>
> More info here - https://lore.kernel.org/patchwork/patch/1231182/
>
> ---
> drivers/hwtracing/coresight/coresight-replicator.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
> index e7dc1c31d20d..11df63f51071 100644
> --- a/drivers/hwtracing/coresight/coresight-replicator.c
> +++ b/drivers/hwtracing/coresight/coresight-replicator.c
> @@ -68,6 +68,17 @@ static int dynamic_replicator_enable(struct replicator_drvdata *drvdata,
> int rc = 0;
> u32 reg;
>
> + /*
> + * On some QCOM SoCs with replicators in Always-On domain, disabling
> + * clock will result in replicator losing its context. Currently
> + * as a part of pm_runtime workqueue, amba_pm_runtime_suspend disables
> + * clock assuming the context is not lost which is not true for cases
> + * with hardware limitations as the above.
> + */
> + if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0) &&
> + (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0))
> + dynamic_replicator_reset(drvdata);
> +
Based on your comment here[1] and the ongoing conversation, I will
wait for a V2.
Thanks,
Mathieu
[1]. https://lkml.org/lkml/2020/5/11/650
> switch (outport) {
> case 0:
> reg = REPLICATOR_IDFILTER0;
> --
> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
> of Code Aurora Forum, hosted by The Linux Foundation
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] coresight: replicator: Reset replicator if context is lost
2020-05-11 16:19 ` Mathieu Poirier
@ 2020-05-11 16:26 ` Sai Prakash Ranjan
0 siblings, 0 replies; 3+ messages in thread
From: Sai Prakash Ranjan @ 2020-05-11 16:26 UTC (permalink / raw)
To: Mathieu Poirier
Cc: Suzuki K Poulose, Mike Leach, linux-arm-msm, Coresight ML,
Linux Kernel Mailing List, Stephen Boyd, linux-arm-kernel
Hi Mathieu,
On 2020-05-11 21:49, Mathieu Poirier wrote:
> Hi Sai,
>
> On Mon, 11 May 2020 at 02:34, Sai Prakash Ranjan
> <saiprakash.ranjan@codeaurora.org> wrote:
>>
>> On some QCOM SoCs, replicators in Always-On domain loses its
>> context as soon as the clock is disabled. Currently as a part
>> of pm_runtime workqueue, clock is disabled after the replicator
>> is initialized by amba_pm_runtime_suspend assuming that context
>> is not lost which is not true for replicators with such
>> limitations. Hence check the replicator idfilter registers
>> in dynamic_replicator_enable() and reset again.
>>
>> Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
>> ---
>>
>> More info here - https://lore.kernel.org/patchwork/patch/1231182/
>>
>> ---
>> drivers/hwtracing/coresight/coresight-replicator.c | 11 +++++++++++
>> 1 file changed, 11 insertions(+)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-replicator.c
>> b/drivers/hwtracing/coresight/coresight-replicator.c
>> index e7dc1c31d20d..11df63f51071 100644
>> --- a/drivers/hwtracing/coresight/coresight-replicator.c
>> +++ b/drivers/hwtracing/coresight/coresight-replicator.c
>> @@ -68,6 +68,17 @@ static int dynamic_replicator_enable(struct
>> replicator_drvdata *drvdata,
>> int rc = 0;
>> u32 reg;
>>
>> + /*
>> + * On some QCOM SoCs with replicators in Always-On domain,
>> disabling
>> + * clock will result in replicator losing its context.
>> Currently
>> + * as a part of pm_runtime workqueue, amba_pm_runtime_suspend
>> disables
>> + * clock assuming the context is not lost which is not true
>> for cases
>> + * with hardware limitations as the above.
>> + */
>> + if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0)
>> &&
>> + (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) ==
>> 0))
>> + dynamic_replicator_reset(drvdata);
>> +
>
> Based on your comment here[1] and the ongoing conversation, I will
> wait for a V2.
>
> Thanks,
> Mathieu
>
> [1]. https://lkml.org/lkml/2020/5/11/650
>
Yes, I will post a v2 once we have consensus regarding which way we need
to
add a workaround for such QCOM SoCs.
Thanks,
Sai
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member
of Code Aurora Forum, hosted by The Linux Foundation
^ permalink raw reply [flat|nested] 3+ messages in thread
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2020-05-11 8:34 [PATCH] coresight: replicator: Reset replicator if context is lost Sai Prakash Ranjan
2020-05-11 16:19 ` Mathieu Poirier
2020-05-11 16:26 ` Sai Prakash Ranjan
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