Hi Mike,
-----Original Message----- From: Mike Leach mike.leach@linaro.org Sent: Friday, January 5, 2024 9:41 PM To: Linu Cherian lcherian@marvell.com Cc: suzuki.poulose@arm.com; james.clark@arm.com; leo.yan@linaro.org; linux-arm-kernel@lists.infradead.org; coresight@lists.linaro.org; linux- kernel@vger.kernel.org; robh+dt@kernel.org; krzysztof.kozlowski+dt@linaro.org; conor+dt@kernel.org; devicetree@vger.kernel.org; Sunil Kovvuri Goutham sgoutham@marvell.com; George Cherian gcherian@marvell.com Subject: [EXT] Re: [PATCH v6 6/7] coresight: tmc: Stop trace capture on FlIn
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Hi,
On Fri, 5 Jan 2024 at 05:59, Linu Cherian lcherian@marvell.com wrote:
Configure TMC ETR and ETF to flush and stop trace capture on FlIn event. As a side effect, do manual flush only if auto flush fails.
Signed-off-by: Linu Cherian lcherian@marvell.com
Changelog from v5:
- No changes
drivers/hwtracing/coresight/coresight-tmc-etf.c | 10 ++++++++-- drivers/hwtracing/coresight/coresight-tmc-etr.c | 10 ++++++++-- drivers/hwtracing/coresight/coresight-tmc.h | 3 +++ 3 files changed, 19 insertions(+), 4 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c index 72c2315f4e23..57a9a9300d36 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -34,7 +34,7 @@ static int __tmc_etb_enable_hw(struct tmc_drvdata
*drvdata)
writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base +TMC_MODE);
writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT |
TMC_FFCR_TRIGON_TRIGIN,
TMC_FFCR_TRIGON_TRIGIN |- TMC_FFCR_STOP_ON_FLUSH, drvdata->base + TMC_FFCR);
This is a problem. Setting TMC_FFCR_STOP_ON_FLUSH changes the fundamentals of trigger event handling. Without this bit ETM can generate multiple event + triggers which are then embedded into the formatted trace stream for later search. With this new bit the capture will stop on the first event. Setting this bit should be dependent on the mode being set to ETR_MODE_RESRV
Okay, will add a configuration dependency here.
writel_relaxed(drvdata->trigger_cntr, drvdata->base +TMC_TRG); @@ -615,7 +615,13 @@ static int tmc_panic_sync_etf(struct
coresight_device *csdev)
if (val != TMC_MODE_CIRCULAR_BUFFER) goto out;
tmc_flush_and_stop(drvdata);
val = readl(drvdata->base + TMC_FFSR);/* Do manual flush and stop only if its not auto-stopped */if (!(val & TMC_FFSR_FT_STOPPED)) {dev_info(&csdev->dev,"%s: Triggering manual flush\n", __func__);tmc_flush_and_stop(drvdata);}Is there some reason to believe that the stop on flush will not work?
CTI misconfiguration or even skipping the CTI configuration could be the reasons.
Using this conditional skips the tmc_wait_for_tmcready() called by tmc_flush_and_stop() if the formatter is stopped - which is a different condition test on a different register.
Okay got it. While add a tmc_wait_for_tmcready() for the event based flush as well.
Why is this block of code not in the patch that introduces the tmc_panic_sync_etf()
Ack. Will merge the above block of code alone to the patch that introduces tmc_panic_sync_xxx
/* Sync registers from hardware to metadata region */ mdata->sts = csdev_access_relaxed_read32(csa, TMC_STS); diff--git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index ab7521bbb2f5..4b3c7ec7f62b 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -1113,7 +1113,7 @@ static int __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT |
TMC_FFCR_TRIGON_TRIGIN,
TMC_FFCR_TRIGON_TRIGIN |- TMC_FFCR_STOP_ON_FLUSH, drvdata->base + TMC_FFCR); writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG); tmc_enable_hw(drvdata);
@@ -1846,7 +1846,13 @@ static int tmc_panic_sync_etr(struct
coresight_device *csdev)
if (!(val & TMC_CTL_CAPT_EN)) goto out;
tmc_flush_and_stop(drvdata);
val = readl(drvdata->base + TMC_FFSR);/* Do manual flush and stop only if its not auto-stopped */if (!(val & TMC_FFSR_FT_STOPPED)) {dev_info(&csdev->dev,"%s: Triggering manual flush\n", __func__);tmc_flush_and_stop(drvdata);}Above comments for etf apply equally to etr.
Ack.
Linu Cherian