Commit 722adbbd authored by Stanley Chu's avatar Stanley Chu Committed by Martin K. Petersen
Browse files

scsi: ufs: ufs-mediatek: gate ref-clk during Auto-Hibern8 

In current UFS driver design, hba->uic_link_state will not be changed after
link enters Hibern8 state by Auto-Hibern8 mechanism.  In this case,
reference clock gating will be skipped unless special handling is
implemented in vendor's callbacks.

Support reference clock gating during Auto-Hibern8 period in MediaTek
Chipsets: If link state is already in Hibern8 while Auto-Hibern8 feature is
enabled, gate reference clock in setup_clocks callback.

Link: https://lore.kernel.org/r/20200129105251.12466-5-stanley.chu@mediatek.com


Reviewed-by: default avatarAlim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: default avatarBean Huo <beanhuo@micron.com>
Signed-off-by: default avatarStanley Chu <stanley.chu@mediatek.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 5a244e0e

drivers/scsi/ufs/ufs-mediatek.c

+27 −11
Original line number Diff line number Diff line
@@ -143,6 +143,17 @@ out: 
	return 0;

}



static u32 ufs_mtk_link_get_state(struct ufs_hba *hba)

{

	u32 val;



	ufshcd_writel(hba, 0x20, REG_UFS_DEBUG_SEL);

	val = ufshcd_readl(hba, REG_UFS_PROBE);

	val = val >> 28;



	return val;

}



/**

 * ufs_mtk_setup_clocks - enables/disable clocks

 * @hba: host controller instance
@@ -155,7 +166,7 @@ static int ufs_mtk_setup_clocks(struct ufs_hba *hba, bool on, 
				enum ufs_notify_change_status status)

{

	struct ufs_mtk_host *host = ufshcd_get_variant(hba);

	int ret = -EINVAL;

	int ret = 0;



	/*

	 * In case ufs_mtk_init() is not yet done, simply ignore.
@@ -165,20 +176,25 @@ static int ufs_mtk_setup_clocks(struct ufs_hba *hba, bool on, 
	if (!host)

		return 0;



	switch (status) {

	case PRE_CHANGE:

		if (!on && !ufshcd_is_link_active(hba)) {

	if (!on && status == PRE_CHANGE) {

		if (!ufshcd_is_link_active(hba)) {

			ufs_mtk_setup_ref_clk(hba, on);

			ret = phy_power_off(host->mphy);

		} else {

			/*

			 * Gate ref-clk if link state is in Hibern8

			 * triggered by Auto-Hibern8.

			 */

			if (!ufshcd_can_hibern8_during_gating(hba) &&

			    ufshcd_is_auto_hibern8_enabled(hba) &&

			    ufs_mtk_link_get_state(hba) ==

			    VS_LINK_HIBERN8)

				ufs_mtk_setup_ref_clk(hba, on);

		}

		break;

	case POST_CHANGE:

		if (on) {

	} else if (on && status == POST_CHANGE) {

		ret = phy_power_on(host->mphy);

		ufs_mtk_setup_ref_clk(hba, on);

	}

		break;

	}



	return ret;

}

drivers/scsi/ufs/ufs-mediatek.h

+12 −0
Original line number Diff line number Diff line
@@ -53,6 +53,18 @@ 
#define VS_SAVEPOWERCONTROL         0xD0A6

#define VS_UNIPROPOWERDOWNCONTROL   0xD0A8



/*

 * Vendor specific link state

 */

enum {

	VS_LINK_DISABLED            = 0,

	VS_LINK_DOWN                = 1,

	VS_LINK_UP                  = 2,

	VS_LINK_HIBERN8             = 3,

	VS_LINK_LOST                = 4,

	VS_LINK_CFG                 = 5,

};



/*

 * SiP commands

 */

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