From 8013f32a1b352f810cc2acfb00317df2ae3c5dee Mon Sep 17 00:00:00 2001
From: Mathieu Poirier <mathieu.poirier@linaro.org>
Date: Thu, 25 Apr 2019 13:52:53 -0600
Subject: [PATCH] coresight: etm4x: Skip selector pair 0

Resource selector pair 0 is always implemented and reserved.  As such
it should not be explicitly programmed.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/hwtracing/coresight/coresight-etm4x.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 732ae12fca9b..d64192c29860 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -138,8 +138,11 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 			       drvdata->base + TRCCNTVRn(i));
 	}
 
-	/* Resource selector pair 0 is always implemented and reserved */
-	for (i = 0; i < drvdata->nr_resource * 2; i++)
+	/*
+	 * Resource selector pair 0 is always implemented and reserved.  As
+	 * such start at 2.
+	 */
+	for (i = 2; i < drvdata->nr_resource * 2; i++)
 		writel_relaxed(config->res_ctrl[i],
 			       drvdata->base + TRCRSCTLRn(i));