scsi: ufs: ufs-mediatek: Disable reset confirm feature by UniPro

In MediaTek UFS platforms, UniPro will not return reset confirm if it is in
POWERDOWN state thus hang issue may happen while disabling UFSHCI. Simply
disable this feature before UniPro leaves POWERDOWN state.

Link: https://lore.kernel.org/r/20220623035052.18802-6-stanley.chu@mediatek.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Po-Wen Kao <powen.kao@mediatek.com>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/ufs/host/ufs-mediatek.c

@@ -1079,6 +1079,11 @@ static int ufs_mtk_link_set_lpm(struct ufs_hba *hba)
 {
 	int err;
 
+	/* Disable reset confirm feature by UniPro */
+	ufshcd_writel(hba,
+		      (ufshcd_readl(hba, REG_UFS_XOUFS_CTRL) & ~0x100),
+		      REG_UFS_XOUFS_CTRL);
+
 	err = ufs_mtk_unipro_set_lpm(hba, true);
 	if (err) {
 		/* Resume UniPro state for following error recovery */