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From: Mike Leach <mike.leach@linaro.org>
Date: Thu, 16 Jul 2020 11:57:39 -0600
Subject: coresight: etmv4: Counter values not saved on disable

Git-commit: 8fa43700f69703f995ea715b76be6fabdd2f05de
Patch-mainline: v5.9-rc1
References: jsc#SLE-13629,jsc#SLE-14776

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.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
 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 2290f41f0074..2d732af8b3e7 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -511,6 +511,12 @@ 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);
-- 
2.26.2