diff mbox series

[4/6] coresight: etm3x: Deal with CLAIM tag before and after accessing HW

Message ID 1543603387-32645-5-git-send-email-mathieu.poirier@linaro.org
State New
Headers show
Series coresight: next v4.20-rc4 | expand

Commit Message

Mathieu Poirier Nov. 30, 2018, 6:43 p.m. UTC 
This patch moves access to the CLAIM tag so that no modification to the HW
happens before and after the CLAIM operation has been carried.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>

---
 drivers/hwtracing/coresight/coresight-etm3x.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

-- 
2.7.4
diff mbox series

Patch

diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index fd5c4cca7db5..6f30d52da9e4 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -363,15 +363,16 @@  static int etm_enable_hw(struct etm_drvdata *drvdata)
 
 	CS_UNLOCK(drvdata->base);
 
+	rc = coresight_claim_device_unlocked(drvdata->base);
+	if (rc)
+		goto done;
+
 	/* Turn engine on */
 	etm_clr_pwrdwn(drvdata);
 	/* Apply power to trace registers */
 	etm_set_pwrup(drvdata);
 	/* Make sure all registers are accessible */
 	etm_os_unlock(drvdata);
-	rc = coresight_claim_device_unlocked(drvdata->base);
-	if (rc)
-		goto done;
 
 	etm_set_prog(drvdata);
 
@@ -422,8 +423,6 @@  static int etm_enable_hw(struct etm_drvdata *drvdata)
 	etm_clr_prog(drvdata);
 
 done:
-	if (rc)
-		etm_set_pwrdwn(drvdata);
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "cpu: %d enable smp call done: %d\n",
@@ -577,9 +576,9 @@  static void etm_disable_hw(void *info)
 	for (i = 0; i < drvdata->nr_cntr; i++)
 		config->cntr_val[i] = etm_readl(drvdata, ETMCNTVRn(i));
 
+	etm_set_pwrdwn(drvdata);
 	coresight_disclaim_device_unlocked(drvdata->base);
 
-	etm_set_pwrdwn(drvdata);
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "cpu: %d disable smp call done\n", drvdata->cpu);