diff mbox

[V6,03/26] coresight: etm3x: unlocking tracers in default arch init

Message ID 1449176702-13213-4-git-send-email-mathieu.poirier@linaro.org
State Accepted
Commit ae69a1da399fccaed406932f5cbee55a6f9d4425
Headers show

Commit Message

Mathieu Poirier Dec. 3, 2015, 9:04 p.m. UTC 
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>

---
 drivers/hwtracing/coresight/coresight-etm3x.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

-- 
2.1.4


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diff mbox

Patch

diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 2a1950d0753d..737b6164f4a5 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -47,11 +47,11 @@  static struct etm_drvdata *etmdrvdata[NR_CPUS];
  * 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();
 }
 
@@ -478,6 +478,9 @@  static void etm_init_arch_data(void *info)
 	u32 etmccr;
 	struct etm_drvdata *drvdata = info;
 
+	/* Make sure all registers are accessible */
+	etm_os_unlock(drvdata);
+
 	CS_UNLOCK(drvdata->base);
 
 	/* First dummy read */
@@ -602,9 +605,6 @@  static int etm_probe(struct amba_device *adev, const struct amba_id *id)
 	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");