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From:   Alim Akhtar <alim.akhtar@samsung.com>
To:     robh@kernel.org
Cc:     devicetree@vger.kernel.org, linux-scsi@vger.kernel.org,
        krzk@kernel.org, avri.altman@wdc.com, martin.petersen@oracle.com,
        kwmad.kim@samsung.com, stanley.chu@mediatek.com,
        cang@codeaurora.org, linux-samsung-soc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Alim Akhtar <alim.akhtar@samsung.com>
Subject: [PATCH v6 03/10] scsi: ufs: add quirk to enable host controller
 without hce
Date:   Fri, 17 Apr 2020 23:29:37 +0530
Message-Id: <20200417175944.47189-4-alim.akhtar@samsung.com>
In-Reply-To: <20200417175944.47189-1-alim.akhtar@samsung.com>
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References: <20200417175944.47189-1-alim.akhtar@samsung.com>
        <CGME20200417181012epcas5p2004ac8f0d793abd4d58c096ff490da68@epcas5p2.samsung.com>
Sender: linux-kernel-owner@vger.kernel.org
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Some host controllers don't support host controller enable via HCE.

Signed-off-by: Seungwon Jeon <essuuj@gmail.com>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
---
 drivers/scsi/ufs/ufshcd.c | 76 +++++++++++++++++++++++++++++++++++++--
 drivers/scsi/ufs/ufshcd.h |  6 ++++
 2 files changed, 80 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 0e9704da58bd..ee30ed6cc805 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3534,6 +3534,52 @@ static int ufshcd_dme_link_startup(struct ufs_hba *hba)
 			"dme-link-startup: error code %d\n", ret);
 	return ret;
 }
+/**
+ * ufshcd_dme_reset - UIC command for DME_RESET
+ * @hba: per adapter instance
+ *
+ * DME_RESET command is issued in order to reset UniPro stack.
+ * This function now deal with cold reset.
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int ufshcd_dme_reset(struct ufs_hba *hba)
+{
+	struct uic_command uic_cmd = {0};
+	int ret;
+
+	uic_cmd.command = UIC_CMD_DME_RESET;
+
+	ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
+	if (ret)
+		dev_err(hba->dev,
+			"dme-reset: error code %d\n", ret);
+
+	return ret;
+}
+
+/**
+ * ufshcd_dme_enable - UIC command for DME_ENABLE
+ * @hba: per adapter instance
+ *
+ * DME_ENABLE command is issued in order to enable UniPro stack.
+ *
+ * Returns 0 on success, non-zero value on failure
+ */
+static int ufshcd_dme_enable(struct ufs_hba *hba)
+{
+	struct uic_command uic_cmd = {0};
+	int ret;
+
+	uic_cmd.command = UIC_CMD_DME_ENABLE;
+
+	ret = ufshcd_send_uic_cmd(hba, &uic_cmd);
+	if (ret)
+		dev_err(hba->dev,
+			"dme-reset: error code %d\n", ret);
+
+	return ret;
+}
 
 static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba)
 {
@@ -4251,7 +4297,7 @@ static inline void ufshcd_hba_stop(struct ufs_hba *hba, bool can_sleep)
 }
 
 /**
- * ufshcd_hba_enable - initialize the controller
+ * ufshcd_hba_execute_hce - initialize the controller
  * @hba: per adapter instance
  *
  * The controller resets itself and controller firmware initialization
@@ -4260,7 +4306,7 @@ static inline void ufshcd_hba_stop(struct ufs_hba *hba, bool can_sleep)
  *
  * Returns 0 on success, non-zero value on failure
  */
-int ufshcd_hba_enable(struct ufs_hba *hba)
+static int ufshcd_hba_execute_hce(struct ufs_hba *hba)
 {
 	int retry;
 
@@ -4308,6 +4354,32 @@ int ufshcd_hba_enable(struct ufs_hba *hba)
 
 	return 0;
 }
+
+int ufshcd_hba_enable(struct ufs_hba *hba)
+{
+	int ret;
+
+	if (hba->quirks & UFSHCI_QUIRK_BROKEN_HCE) {
+		ufshcd_set_link_off(hba);
+		ufshcd_vops_hce_enable_notify(hba, PRE_CHANGE);
+
+		/* enable UIC related interrupts */
+		ufshcd_enable_intr(hba, UFSHCD_UIC_MASK);
+		ret = ufshcd_dme_reset(hba);
+		if (!ret) {
+			ret = ufshcd_dme_enable(hba);
+			if (!ret)
+				ufshcd_vops_hce_enable_notify(hba, POST_CHANGE);
+			if (ret)
+				dev_err(hba->dev,
+					"Host controller enable failed with non-hce\n");
+		}
+	} else {
+		ret = ufshcd_hba_execute_hce(hba);
+	}
+
+	return ret;
+}
 EXPORT_SYMBOL_GPL(ufshcd_hba_enable);
 
 static int ufshcd_disable_tx_lcc(struct ufs_hba *hba, bool peer)
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 53096642f9a8..f8d08cb9caf7 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -529,6 +529,12 @@ enum ufshcd_quirks {
 	 * that the interrupt aggregation timer and counter are reset by s/w.
 	 */
 	UFSHCI_QUIRK_SKIP_RESET_INTR_AGGR		= 1 << 7,
+
+	/*
+	 * This quirks needs to be enabled if host controller cannot be
+	 * enabled via HCE register.
+	 */
+	UFSHCI_QUIRK_BROKEN_HCE				= 1 << 8,
 };
 
 enum ufshcd_caps {
-- 
2.17.1