coresight-etm: Fix initial trace ID value

The coresight TRM specify that a component's trace ID should
be other than 0.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/coresight/coresight-etm3x.c b/drivers/coresight/coresight-etm3x.c
index 369cac00afaa..73c36696f1b6 100644
--- a/drivers/coresight/coresight-etm3x.c
+++ b/drivers/coresight/coresight-etm3x.c
@@ -1749,7 +1749,11 @@ static void etm_init_arch_data(void *info)
 
 static void etm_init_default_data(struct etm_drvdata *drvdata)
 {
-        static int etm3x_traceid;
+        /*
+         * A trace ID of value 0 is invalid, so let's start at some
+         * random value that fits in 7 bits and will be just as good.
+         */
+        static int etm3x_traceid = 0x10;
 
         u32 flags = (1 << 0 | /* instruction execute*/
                      3 << 3 | /* ARM instruction */