| Message ID | 20200511083400.26554-1-saiprakash.ranjan@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | coresight: replicator: Reset replicator if context is lost | expand |
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
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
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;
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(+)