diff options
author | Anshuman Khandual <anshuman.khandual@arm.com> | 2023-09-21 06:36:30 +0300 |
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committer | Suzuki K Poulose <suzuki.poulose@arm.com> | 2023-11-16 14:35:06 +0300 |
commit | 94566c5b07744c7cf5c7cc0ad42b15996ba0b054 (patch) | |
tree | a5c652aac5e5d90c788aa156e4a842c54b9e6c8d /drivers/hwtracing/coresight/coresight-etm4x-core.c | |
parent | 4aff040bcc8de28bead01194cbca1dc9471a5a85 (diff) | |
download | linux-94566c5b07744c7cf5c7cc0ad42b15996ba0b054.tar.xz |
coresight: etm: Make cycle count threshold user configurable
When cycle counting is enabled, we use a default threshold value i.e 0x100
for the instruction trace cycle counting.
This patch makes the cycle threshold user configurable via perf event
attributes( 'cc_threshold' => event->attr.config3[11:0] ), falling back
to the current default if unspecified.
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230921033631.1298723-3-anshuman.khandual@arm.com
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-etm4x-core.c')
-rw-r--r-- | drivers/hwtracing/coresight/coresight-etm4x-core.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 5feb2bd41ee5..285539104bcc 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -644,7 +644,7 @@ static int etm4_parse_event_config(struct coresight_device *csdev, struct etmv4_config *config = &drvdata->config; struct perf_event_attr *attr = &event->attr; unsigned long cfg_hash; - int preset; + int preset, cc_threshold; /* Clear configuration from previous run */ memset(config, 0, sizeof(struct etmv4_config)); @@ -667,7 +667,12 @@ static int etm4_parse_event_config(struct coresight_device *csdev, if (attr->config & BIT(ETM_OPT_CYCACC)) { config->cfg |= TRCCONFIGR_CCI; /* TRM: Must program this for cycacc to work */ - config->ccctlr = ETM_CYC_THRESHOLD_DEFAULT; + cc_threshold = attr->config3 & ETM_CYC_THRESHOLD_MASK; + if (!cc_threshold) + cc_threshold = ETM_CYC_THRESHOLD_DEFAULT; + if (cc_threshold < drvdata->ccitmin) + cc_threshold = drvdata->ccitmin; + config->ccctlr = cc_threshold; } if (attr->config & BIT(ETM_OPT_TS)) { /* |