Re: [PATCH v1] slimbus: qcom-ngd-ctrl: Reduce auto suspend delay

From: Viken Dadhaniya
Date: Fri Mar 08 2024 - 07:43:58 EST




On 3/6/2024 2:46 AM, Konrad Dybcio wrote:


On 3/4/24 14:50, Viken Dadhaniya wrote:
Currently we have auto suspend delay of 1s which is
very high and it takes long time to driver for runtime
suspend after use case is done.

Hence to optimize runtime PM ops, reduce auto suspend
delay to 100ms.

Signed-off-by: Viken Dadhaniya <quic_vdadhani@xxxxxxxxxxx>
---

What determines 1s to be high and 100ms to be low enough? Could
you share some more reasoning?

Right now we don't have exact number which can quantify either power or performance. But we are following small window so as to not keep timer running longer while having resources like Clock ON. Theoretically and testing wise, this is not creating any side effect too.


  drivers/slimbus/qcom-ngd-ctrl.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
index efeba8275a66..5de45a0e3da5 100644
--- a/drivers/slimbus/qcom-ngd-ctrl.c
+++ b/drivers/slimbus/qcom-ngd-ctrl.c
@@ -81,7 +81,7 @@
  #define SLIM_USR_MC_DISCONNECT_PORT    0x2E
  #define SLIM_USR_MC_REPEAT_CHANGE_VALUE    0x0
-#define QCOM_SLIM_NGD_AUTOSUSPEND    MSEC_PER_SEC
+#define QCOM_SLIM_NGD_AUTOSUSPEND    (MSEC_PER_SEC / 10)

This could be a good opportunity to inline this value..

Updated in v2.


Konrad