RE: [PATCH v1] scsi: ufs: change msleep to usleep_range

From: Avri Altman
Date: Tue Jul 16 2019 - 02:54:57 EST


>
> From: Bean Huo <beanhuo@xxxxxxxxxx>
>
> This patch is to change msleep() to usleep_range() based on
> Documentation/timers/timers-howto.txt. It suggests using
> usleep_range() for small msec(1ms - 20ms) since msleep()
> will often sleep longer than desired value.
>
> After changing, booting time will be 5ms-10ms faster than before.
> I tested this change on two different platforms, one has 5ms faster,
> another one is about 10ms. I think this is different on different
> platform.
>
> Actually, from UFS host side, 1ms-5ms delay is already sufficient for
> its initialization of the local UIC layer.
>
> Fixes: 7a3e97b0dc4b ([SCSI] ufshcd: UFS Host controller driver)
> Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
Reviewed-by: Avri Altman <avri.altman@xxxxxxx>