[PATCH v8 6/7] coresight: tmc: Stop trace capture on FlIn
From: Linu Cherian
Date: Fri May 31 2024 - 00:29:30 EST
Configure TMC ETR and ETF to flush and stop trace capture
on FlIn event based on sysfs attribute,
/sys/bus/coresight/devices/tmc_etXn/stop_on_flush.
Signed-off-by: Linu Cherian <lcherian@xxxxxxxxxxx>
---
Changelog from v7:
* Honour stop_on_flush sysfs attribute for perf sessions as well.
This allows user to start trace sessions using perf method as
well to use the Coresight kernel panic support.
.../hwtracing/coresight/coresight-tmc-core.c | 31 +++++++++++++++++++
.../hwtracing/coresight/coresight-tmc-etf.c | 18 ++++++++---
.../hwtracing/coresight/coresight-tmc-etr.c | 18 ++++++++---
drivers/hwtracing/coresight/coresight-tmc.h | 4 +++
4 files changed, 61 insertions(+), 10 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index aaa9de9f4cd2..24edd9d750c3 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -452,9 +452,40 @@ static ssize_t buffer_size_store(struct device *dev,
static DEVICE_ATTR_RW(buffer_size);
+static ssize_t stop_on_flush_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ return sprintf(buf, "%#x\n", drvdata->stop_on_flush);
+}
+
+static ssize_t stop_on_flush_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ u8 val;
+ struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ ret = kstrtou8(buf, 0, &val);
+ if (ret)
+ return ret;
+ if (val)
+ drvdata->stop_on_flush = true;
+ else
+ drvdata->stop_on_flush = false;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(stop_on_flush);
+
+
static struct attribute *coresight_tmc_attrs[] = {
&dev_attr_trigger_cntr.attr,
&dev_attr_buffer_size.attr,
+ &dev_attr_stop_on_flush.attr,
NULL,
};
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 655c0c0ba54b..1529b9cc210a 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -19,6 +19,7 @@ static int tmc_set_etf_buffer(struct coresight_device *csdev,
static int __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
{
int rc = 0;
+ u32 ffcr;
CS_UNLOCK(drvdata->base);
@@ -32,10 +33,12 @@ 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,
- drvdata->base + TMC_FFCR);
+
+ ffcr = TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN |
+ TMC_FFCR_FON_TRIG_EVT | TMC_FFCR_TRIGON_TRIGIN;
+ if (drvdata->stop_on_flush_en)
+ ffcr |= TMC_FFCR_STOP_ON_FLUSH;
+ writel_relaxed(ffcr, drvdata->base + TMC_FFCR);
writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG);
tmc_enable_hw(drvdata);
@@ -225,7 +228,8 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
used = true;
drvdata->buf = buf;
}
-
+ if (drvdata->stop_on_flush)
+ drvdata->stop_on_flush_en = true;
ret = tmc_etb_enable_hw(drvdata);
if (!ret) {
coresight_set_mode(csdev, CS_MODE_SYSFS);
@@ -288,6 +292,8 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, void *data)
break;
}
+ if (drvdata->stop_on_flush)
+ drvdata->stop_on_flush_en = true;
ret = tmc_etb_enable_hw(drvdata);
if (!ret) {
/* Associate with monitored process. */
@@ -349,6 +355,8 @@ static int tmc_disable_etf_sink(struct coresight_device *csdev)
tmc_etb_disable_hw(drvdata);
/* Dissociate from monitored process. */
drvdata->pid = -1;
+ /* Reset stop on flush */
+ drvdata->stop_on_flush_en = false;
coresight_set_mode(csdev, CS_MODE_DISABLED);
spin_unlock_irqrestore(&drvdata->spinlock, flags);
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 74f53972ce3c..bf2d0932e205 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -1059,7 +1059,7 @@ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata)
static int __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
{
- u32 axictl, sts;
+ u32 axictl, sts, ffcr;
struct etr_buf *etr_buf = drvdata->etr_buf;
int rc = 0;
@@ -1105,10 +1105,12 @@ static int __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
writel_relaxed(sts, drvdata->base + TMC_STS);
}
- writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI |
- TMC_FFCR_FON_FLIN | TMC_FFCR_FON_TRIG_EVT |
- TMC_FFCR_TRIGON_TRIGIN,
- drvdata->base + TMC_FFCR);
+ ffcr = TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI | TMC_FFCR_FON_FLIN |
+ TMC_FFCR_FON_TRIG_EVT | TMC_FFCR_TRIGON_TRIGIN;
+ if (drvdata->stop_on_flush_en)
+ ffcr |= TMC_FFCR_STOP_ON_FLUSH;
+ writel_relaxed(ffcr, drvdata->base + TMC_FFCR);
+
writel_relaxed(drvdata->trigger_cntr, drvdata->base + TMC_TRG);
tmc_enable_hw(drvdata);
@@ -1313,6 +1315,8 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
goto out;
}
+ if (drvdata->stop_on_flush)
+ drvdata->stop_on_flush_en = true;
ret = tmc_etr_enable_hw(drvdata, sysfs_buf);
if (!ret) {
coresight_set_mode(csdev, CS_MODE_SYSFS);
@@ -1758,6 +1762,8 @@ static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
goto unlock_out;
}
+ if (drvdata->stop_on_flush)
+ drvdata->stop_on_flush_en = true;
rc = tmc_etr_enable_hw(drvdata, etr_perf->etr_buf);
if (!rc) {
/* Associate with monitored process. */
@@ -1808,6 +1814,8 @@ static int tmc_disable_etr_sink(struct coresight_device *csdev)
tmc_etr_disable_hw(drvdata);
/* Dissociate from monitored process. */
drvdata->pid = -1;
+ /* Reset stop on flush */
+ drvdata->stop_on_flush_en = false;
coresight_set_mode(csdev, CS_MODE_DISABLED);
/* Reset perf specific data */
drvdata->perf_buf = NULL;
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 528174283ecc..81eadb384b83 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -205,6 +205,8 @@ struct tmc_resrv_buf {
* @spinlock: only one at a time pls.
* @pid: Process ID of the process being monitored by the session
* that is using this component.
+ * @stop_on_flush: Stop on flush trigger user configuration.
+ * @stop_on_flush_en: Stop on flush enable flag
* @buf: Snapshot of the trace data for ETF/ETB.
* @etr_buf: details of buffer used in TMC-ETR
* @len: size of the available trace for ETF/ETB.
@@ -238,6 +240,8 @@ struct tmc_drvdata {
spinlock_t spinlock;
pid_t pid;
bool reading;
+ bool stop_on_flush;
+ bool stop_on_flush_en;
union {
char *buf; /* TMC ETB */
struct etr_buf *etr_buf; /* TMC ETR */
--
2.34.1