[PATCH 14/32] coresight: etm4x: Add kernel configuration for CONTEXTID

From: Mathieu Poirier
Date: Thu Apr 25 2019 - 15:55:18 EST


Set the proper bit in the configuration register when contextID tracing
has been requested by user space. That way PE_CONTEXT elements are
generated by the tracers when a process is installed on a CPU.

Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Tested-by: Leo Yan <leo.yan@xxxxxxxxxx>
Tested-by: Robert Walker <robert.walker@xxxxxxx>
---
drivers/hwtracing/coresight/Kconfig | 1 +
drivers/hwtracing/coresight/coresight-etm-perf.c | 2 ++
drivers/hwtracing/coresight/coresight-etm4x.c | 5 +++++
include/linux/coresight-pmu.h | 2 ++
tools/include/linux/coresight-pmu.h | 2 ++
5 files changed, 12 insertions(+)

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index a40d796f0a4b..18e8d03321d6 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -75,6 +75,7 @@ config CORESIGHT_SOURCE_ETM4X
bool "CoreSight Embedded Trace Macrocell 4.x driver"
depends on ARM64
select CORESIGHT_LINKS_AND_SINKS
+ select PID_IN_CONTEXTIDR
help
This driver provides support for the ETM4.x tracer module, tracing the
instructions that a processor is executing. This is primarily useful
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 25ae56e924bb..bbfed70b3402 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -29,6 +29,7 @@ static DEFINE_PER_CPU(struct coresight_device *, csdev_src);

/* ETMv3.5/PTM's ETMCR is 'config' */
PMU_FORMAT_ATTR(cycacc, "config:" __stringify(ETM_OPT_CYCACC));
+PMU_FORMAT_ATTR(contextid, "config:" __stringify(ETM_OPT_CTXTID));
PMU_FORMAT_ATTR(timestamp, "config:" __stringify(ETM_OPT_TS));
PMU_FORMAT_ATTR(retstack, "config:" __stringify(ETM_OPT_RETSTK));
/* Sink ID - same for all ETMs */
@@ -36,6 +37,7 @@ PMU_FORMAT_ATTR(sinkid, "config2:0-31");

static struct attribute *etm_config_formats_attr[] = {
&format_attr_cycacc.attr,
+ &format_attr_contextid.attr,
&format_attr_timestamp.attr,
&format_attr_retstack.attr,
&format_attr_sinkid.attr,
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 08ce37c9475d..732ae12fca9b 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -239,6 +239,11 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
if (attr->config & BIT(ETM_OPT_TS))
/* bit[11], Global timestamp tracing bit */
config->cfg |= BIT(11);
+
+ if (attr->config & BIT(ETM_OPT_CTXTID))
+ /* bit[6], Context ID tracing bit */
+ config->cfg |= BIT(ETM4_CFG_BIT_CTXTID);
+
/* return stack - enable if selected and supported */
if ((attr->config & BIT(ETM_OPT_RETSTK)) && drvdata->retstack)
/* bit[12], Return stack enable bit */
diff --git a/include/linux/coresight-pmu.h b/include/linux/coresight-pmu.h
index a1a959ba24ff..b0e35eec6499 100644
--- a/include/linux/coresight-pmu.h
+++ b/include/linux/coresight-pmu.h
@@ -12,11 +12,13 @@

/* ETMv3.5/PTM's ETMCR config bit */
#define ETM_OPT_CYCACC 12
+#define ETM_OPT_CTXTID 14
#define ETM_OPT_TS 28
#define ETM_OPT_RETSTK 29

/* ETMv4 CONFIGR programming bits for the ETM OPTs */
#define ETM4_CFG_BIT_CYCACC 4
+#define ETM4_CFG_BIT_CTXTID 6
#define ETM4_CFG_BIT_TS 11
#define ETM4_CFG_BIT_RETSTK 12

diff --git a/tools/include/linux/coresight-pmu.h b/tools/include/linux/coresight-pmu.h
index a1a959ba24ff..b0e35eec6499 100644
--- a/tools/include/linux/coresight-pmu.h
+++ b/tools/include/linux/coresight-pmu.h
@@ -12,11 +12,13 @@

/* ETMv3.5/PTM's ETMCR config bit */
#define ETM_OPT_CYCACC 12
+#define ETM_OPT_CTXTID 14
#define ETM_OPT_TS 28
#define ETM_OPT_RETSTK 29

/* ETMv4 CONFIGR programming bits for the ETM OPTs */
#define ETM4_CFG_BIT_CYCACC 4
+#define ETM4_CFG_BIT_CTXTID 6
#define ETM4_CFG_BIT_TS 11
#define ETM4_CFG_BIT_RETSTK 12

--
2.17.1