From: Mike Leach mike.leach@linaro.org
[ Upstream commit 8fa43700f69703f995ea715b76be6fabdd2f05de ]
The counter value registers change during operation, however this change is not reflected in the values seen by the user in sysfs.
This fixes the issue by reading back the values on disable.
Signed-off-by: Mike Leach mike.leach@linaro.org Fixes: 2e1cdfe184b52 ("coresight-etm4x: Adding CoreSight ETM4x driver") Signed-off-by: Mathieu Poirier mathieu.poirier@linaro.org Link: https://lore.kernel.org/r/20200716175746.3338735-11-mathieu.poirier@linaro.o... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hwtracing/coresight/coresight-etm4x.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index d59e4b1e5ce58..942b362a1f220 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -507,6 +507,12 @@ static void etm4_disable_hw(void *info) readl_relaxed(drvdata->base + TRCSSCSRn(i)); }
+ /* read back the current counter values */ + for (i = 0; i < drvdata->nr_cntr; i++) { + config->cntr_val[i] = + readl_relaxed(drvdata->base + TRCCNTVRn(i)); + } + coresight_disclaim_device_unlocked(drvdata->base);
CS_LOCK(drvdata->base);