coresight: etm3x: unlocking tracers in default arch init
Calling function 'smp_call_function_single()' to unlock a
tracer and calling it again right after to perform the
default initialisation doesn't make sense.
Moving 'etm_os_unlock()' just before making the default
initialisation results in the same outcome while saving
one call to 'smp_call_function_single()'.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 6ea35b3..f2c74bb 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -47,11 +47,11 @@
* and OS lock must be unlocked before any memory mapped access on such
* processors, otherwise memory mapped reads/writes will be invalid.
*/
-static void etm_os_unlock(void *info)
+static void etm_os_unlock(struct etm_drvdata *drvdata)
{
- struct etm_drvdata *drvdata = (struct etm_drvdata *)info;
/* Writing any value to ETMOSLAR unlocks the trace registers */
etm_writel(drvdata, 0x0, ETMOSLAR);
+ drvdata->os_unlock = true;
isb();
}
@@ -483,6 +483,9 @@
u32 etmccr;
struct etm_drvdata *drvdata = info;
+ /* Make sure all registers are accessible */
+ etm_os_unlock(drvdata);
+
CS_UNLOCK(drvdata->base);
/* First dummy read */
@@ -607,9 +610,6 @@
get_online_cpus();
etmdrvdata[drvdata->cpu] = drvdata;
- if (!smp_call_function_single(drvdata->cpu, etm_os_unlock, drvdata, 1))
- drvdata->os_unlock = true;
-
if (smp_call_function_single(drvdata->cpu,
etm_init_arch_data, drvdata, 1))
dev_err(dev, "ETM arch init failed\n");