From 838c1efc6a0adbf44d16e4714f43443db598cdb5 Mon Sep 17 00:00:00 2001 From: Bean Huo Date: Mon, 15 Jul 2019 11:21:10 +0000 Subject: [PATCH] scsi: ufs: change msleep to usleep_range 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 Acked-by: Stanley Chu Reviewed-by: Avri Altman Signed-off-by: Martin K. Petersen --- drivers/scsi/ufs/ufshcd.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 3804a704e565..a383d0f54f5d 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -4226,12 +4226,6 @@ static int ufshcd_hba_execute_hce(struct ufs_hba *hba) { int retry; - /* - * msleep of 1 and 5 used in this function might result in msleep(20), - * but it was necessary to send the UFS FPGA to reset mode during - * development and testing of this driver. msleep can be changed to - * mdelay and retry count can be reduced based on the controller. - */ if (!ufshcd_is_hba_active(hba)) /* change controller state to "reset state" */ ufshcd_hba_stop(hba, true); @@ -4254,7 +4248,7 @@ static int ufshcd_hba_execute_hce(struct ufs_hba *hba) * instruction might be read back. * This delay can be changed based on the controller. */ - msleep(1); + usleep_range(1000, 1100); /* wait for the host controller to complete initialization */ retry = 10; @@ -4266,7 +4260,7 @@ static int ufshcd_hba_execute_hce(struct ufs_hba *hba) "Controller enable failed\n"); return -EIO; } - msleep(5); + usleep_range(5000, 5100); } /* enable UIC related interrupts */ -- 2.30.2