2020-11-27 17:57:31

by Mathieu Poirier

[permalink] [raw]
Subject: [PATCH 01/15] coresight: etm4x: Skip setting LPOVERRIDE bit for qcom,skip-power-up

From: Sai Prakash Ranjan <[email protected]>

There is a bug on the systems supporting to skip power up
(qcom,skip-power-up) where setting LPOVERRIDE bit(low-power
state override behaviour) will result in CPU hangs/lockups
even on the implementations which supports it. So skip
setting the LPOVERRIDE bit for such platforms.

Cc: [email protected]
Fixes: 02510a5aa78d ("coresight: etm4x: Add support to skip trace unit power up")
Signed-off-by: Sai Prakash Ranjan <[email protected]>
Reviewed-by: Suzuki K Poulose <[email protected]>
Signed-off-by: Mathieu Poirier <[email protected]>
---
drivers/hwtracing/coresight/coresight-etm4x-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index abd706b216ac..6096d7abf80d 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -779,7 +779,7 @@ static void etm4_init_arch_data(void *info)
* LPOVERRIDE, bit[23] implementation supports
* low-power state override
*/
- if (BMVAL(etmidr5, 23, 23))
+ if (BMVAL(etmidr5, 23, 23) && (!drvdata->skip_power_up))
drvdata->lpoverride = true;
else
drvdata->lpoverride = false;
--
2.25.1