From:   "Bao D. Nguyen" <quic_nguyenb@quicinc.com>
To:     <quic_asutoshd@quicinc.com>, <quic_cang@quicinc.com>,
        <bvanassche@acm.org>, <mani@kernel.org>,
        <stanley.chu@mediatek.com>, <adrian.hunter@intel.com>,
        <beanhuo@micron.com>, <avri.altman@wdc.com>,
        <martin.petersen@oracle.com>
CC:     <linux-scsi@vger.kernel.org>,
        "Bao D. Nguyen" <quic_nguyenb@quicinc.com>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        "Arthur Simchaev" <Arthur.Simchaev@wdc.com>,
        open list <linux-kernel@vger.kernel.org>,
        "open list:UNIVERSAL FLASH STORAGE HOST CONTROLLER DRIVER..." 
        <linux-arm-msm@vger.kernel.org>
Subject: [RFC PATCH v1 1/4] ufs: mcq: Use ufshcd_mcq_poll_cqe_lock() in mcq mode
Date:   Tue, 7 Mar 2023 20:01:41 -0800
Message-ID: <b4f9153f9181506a954da1a877dbd3a222982dd0.1678247309.git.quic_nguyenb@quicinc.com>
In-Reply-To: <cover.1678247309.git.quic_nguyenb@quicinc.com>
References: <cover.1678247309.git.quic_nguyenb@quicinc.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

In preparation for adding mcq error handler support, update the mcq
code to use the ufshcd_mcq_poll_cqe_lock() in interrupt context
instead of using ufshcd_mcq_poll_cqe_nolock(). This is to keep
synchronization between mcq interrupt and error handler contexts
because both need to access the mcq hardware in separate contexts.

Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
---
 drivers/ufs/core/ufs-mcq.c     | 6 +++---
 drivers/ufs/core/ufshcd-priv.h | 2 --
 drivers/ufs/core/ufshcd.c      | 2 +-
 drivers/ufs/host/ufs-qcom.c    | 2 +-
 include/ufs/ufshcd.h           | 2 +-
 5 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/ufs/core/ufs-mcq.c b/drivers/ufs/core/ufs-mcq.c
index 31df052..63729dd 100644
--- a/drivers/ufs/core/ufs-mcq.c
+++ b/drivers/ufs/core/ufs-mcq.c
@@ -277,8 +277,8 @@ static void ufshcd_mcq_process_cqe(struct ufs_hba *hba,
 	ufshcd_compl_one_cqe(hba, tag, cqe);
 }
 
-unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
-					 struct ufs_hw_queue *hwq)
+static unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
+						struct ufs_hw_queue *hwq)
 {
 	unsigned long completed_reqs = 0;
 
@@ -294,7 +294,6 @@ unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
 
 	return completed_reqs;
 }
-EXPORT_SYMBOL_GPL(ufshcd_mcq_poll_cqe_nolock);
 
 unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 				       struct ufs_hw_queue *hwq)
@@ -307,6 +306,7 @@ unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 
 	return completed_reqs;
 }
+EXPORT_SYMBOL_GPL(ufshcd_mcq_poll_cqe_lock);
 
 void ufshcd_mcq_make_queues_operational(struct ufs_hba *hba)
 {
diff --git a/drivers/ufs/core/ufshcd-priv.h b/drivers/ufs/core/ufshcd-priv.h
index 529f850..9597e955 100644
--- a/drivers/ufs/core/ufshcd-priv.h
+++ b/drivers/ufs/core/ufshcd-priv.h
@@ -71,8 +71,6 @@ void ufshcd_mcq_config_mac(struct ufs_hba *hba, u32 max_active_cmds);
 void ufshcd_mcq_select_mcq_mode(struct ufs_hba *hba);
 u32 ufshcd_mcq_read_cqis(struct ufs_hba *hba, int i);
 void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i);
-unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
-					 struct ufs_hw_queue *hwq);
 struct ufs_hw_queue *ufshcd_mcq_req_to_hwq(struct ufs_hba *hba,
 					   struct request *req);
 unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index 629442c..e4d1b4e 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -6739,7 +6739,7 @@ static irqreturn_t ufshcd_handle_mcq_cq_events(struct ufs_hba *hba)
 			ufshcd_mcq_write_cqis(hba, events, i);
 
 		if (events & UFSHCD_MCQ_CQIS_TAIL_ENT_PUSH_STS)
-			ufshcd_mcq_poll_cqe_nolock(hba, hwq);
+			ufshcd_mcq_poll_cqe_lock(hba, hwq);
 	}
 
 	return IRQ_HANDLED;
diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index 34fc453..c686fb8 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -1558,7 +1558,7 @@ static irqreturn_t ufs_qcom_mcq_esi_handler(int irq, void *__hba)
 	struct ufs_hw_queue *hwq = &hba->uhq[id];
 
 	ufshcd_mcq_write_cqis(hba, 0x1, id);
-	ufshcd_mcq_poll_cqe_nolock(hba, hwq);
+	ufshcd_mcq_poll_cqe_lock(hba, hwq);
 
 	return IRQ_HANDLED;
 }
diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
index 05e4164..5d7f9b2 100644
--- a/include/ufs/ufshcd.h
+++ b/include/ufs/ufshcd.h
@@ -1244,7 +1244,7 @@ void ufshcd_update_evt_hist(struct ufs_hba *hba, u32 id, u32 val);
 void ufshcd_hba_stop(struct ufs_hba *hba);
 void ufshcd_schedule_eh_work(struct ufs_hba *hba);
 void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i);
-unsigned long ufshcd_mcq_poll_cqe_nolock(struct ufs_hba *hba,
+unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
 					 struct ufs_hw_queue *hwq);
 void ufshcd_mcq_enable_esi(struct ufs_hba *hba);
 void ufshcd_mcq_config_esi(struct ufs_hba *hba, struct msi_msg *msg);
-- 
2.7.4