diff options
| author | Stanley Chu <stanley.chu@mediatek.com> | 2020-06-01 13:46:42 +0300 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2020-06-16 06:06:39 +0300 |
| commit | fb43337cd4cff6639b174e3b6766e6eade523836 (patch) | |
| tree | ec6de8d7d90a652bc3eef23cebb94f867df4b2c6 /drivers/scsi/ufs | |
| parent | 55f4b1f73631a0817717fe6e98517de51b4c3527 (diff) | |
| download | linux-fb43337cd4cff6639b174e3b6766e6eade523836.tar.xz | |
scsi: ufs-mediatek: Fix imprecise waiting time for ref-clk control
Currently ref-clk control timeout is implemented by jiffies. However
jiffies is not accurate enough thus "false timeout" may happen.
Use more accurate delay mechanism instead, i.e. ktime.
Link: https://lore.kernel.org/r/20200601104646.15436-2-stanley.chu@mediatek.com
Reviewed-by: Andy Teng <andy.teng@mediatek.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/ufs')
| -rw-r--r-- | drivers/scsi/ufs/ufs-mediatek.c | 7 | ||||
| -rw-r--r-- | drivers/scsi/ufs/ufs-mediatek.h | 2 |
2 files changed, 5 insertions, 4 deletions
diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c index d56ce8d97d4e..523ee5573921 100644 --- a/drivers/scsi/ufs/ufs-mediatek.c +++ b/drivers/scsi/ufs/ufs-mediatek.c @@ -120,7 +120,7 @@ static int ufs_mtk_setup_ref_clk(struct ufs_hba *hba, bool on) { struct ufs_mtk_host *host = ufshcd_get_variant(hba); struct arm_smccc_res res; - unsigned long timeout; + ktime_t timeout, time_checked; u32 value; if (host->ref_clk_enabled == on) @@ -135,8 +135,9 @@ static int ufs_mtk_setup_ref_clk(struct ufs_hba *hba, bool on) } /* Wait for ack */ - timeout = jiffies + msecs_to_jiffies(REFCLK_REQ_TIMEOUT_MS); + timeout = ktime_add_us(ktime_get(), REFCLK_REQ_TIMEOUT_US); do { + time_checked = ktime_get(); value = ufshcd_readl(hba, REG_UFS_REFCLK_CTRL); /* Wait until ack bit equals to req bit */ @@ -144,7 +145,7 @@ static int ufs_mtk_setup_ref_clk(struct ufs_hba *hba, bool on) goto out; usleep_range(100, 200); - } while (time_before(jiffies, timeout)); + } while (ktime_before(time_checked, timeout)); dev_err(hba->dev, "missing ack of refclk req, reg: 0x%x\n", value); diff --git a/drivers/scsi/ufs/ufs-mediatek.h b/drivers/scsi/ufs/ufs-mediatek.h index 5bbd3e9cbae2..fc42dcbfd800 100644 --- a/drivers/scsi/ufs/ufs-mediatek.h +++ b/drivers/scsi/ufs/ufs-mediatek.h @@ -28,7 +28,7 @@ #define REFCLK_REQUEST BIT(0) #define REFCLK_ACK BIT(1) -#define REFCLK_REQ_TIMEOUT_MS 3 +#define REFCLK_REQ_TIMEOUT_US 3000 /* * Vendor specific pre-defined parameters |