[PATCH v1 6/6] scsi: ufs-mediatek: configure and enable clk-gating

From: Stanley Chu
Date: Fri Dec 20 2019 - 03:36:58 EST


Enable clk-gating with customized delayed timer value in
MediaTek Chipsets.

Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
Reviewed-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
---
drivers/scsi/ufs/ufs-mediatek.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)

diff --git a/drivers/scsi/ufs/ufs-mediatek.c b/drivers/scsi/ufs/ufs-mediatek.c
index 71e2e0e4ea11..282ad06ec846 100644
--- a/drivers/scsi/ufs/ufs-mediatek.c
+++ b/drivers/scsi/ufs/ufs-mediatek.c
@@ -205,6 +205,9 @@ static int ufs_mtk_init(struct ufs_hba *hba)
/* Enable runtime autosuspend */
hba->caps |= UFSHCD_CAP_RPM_AUTOSUSPEND;

+ /* Enable clock-gating */
+ hba->caps |= UFSHCD_CAP_CLK_GATING;
+
/*
* ufshcd_vops_init() is invoked after
* ufshcd_setup_clock(true) in ufshcd_hba_init() thus
@@ -293,6 +296,23 @@ static int ufs_mtk_pre_link(struct ufs_hba *hba)
return ret;
}

+static void ufs_mtk_setup_clk_gating(struct ufs_hba *hba)
+{
+ unsigned long flags;
+ u32 ah_ms;
+
+ if (ufshcd_is_clkgating_allowed(hba)) {
+ if (ufshcd_is_auto_hibern8_supported(hba) && hba->ahit)
+ ah_ms = FIELD_GET(UFSHCI_AHIBERN8_TIMER_MASK,
+ hba->ahit);
+ else
+ ah_ms = 10;
+ spin_lock_irqsave(hba->host->host_lock, flags);
+ hba->clk_gating.delay_ms = ah_ms + 5;
+ spin_unlock_irqrestore(hba->host->host_lock, flags);
+ }
+}
+
static int ufs_mtk_post_link(struct ufs_hba *hba)
{
/* disable device LCC */
@@ -308,6 +328,8 @@ static int ufs_mtk_post_link(struct ufs_hba *hba)
FIELD_PREP(UFSHCI_AHIBERN8_SCALE_MASK, 3));
}

+ ufs_mtk_setup_clk_gating(hba);
+
return 0;
}

--
2.18.0