Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Peter Ujfalusi <peter.ujfalusi@ti.com>,
        Tomi Valkeinen <tomi.valkeinen@ti.com>,
        Sasha Levin <alexander.levin@microsoft.com>
Subject: [PATCH 3.18 44/47] drm/omap: DMM: Check for DMM readiness after successful transaction commit
Date:   Fri, 23 Mar 2018 10:55:35 +0100
Message-Id: <20180323094250.001533219@linuxfoundation.org>
In-Reply-To: <20180323094248.117679641@linuxfoundation.org>
References: <20180323094248.117679641@linuxfoundation.org>
User-Agent: quilt/0.65
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Peter Ujfalusi <peter.ujfalusi@ti.com>


[ Upstream commit b7ea6b286c4051e043f691781785e3c4672f014a ]

Check the status of the DMM engine after it is reported that the
transaction was completed as in rare cases the engine might not reached a
working state.

The wait_status() will print information in case the DMM is not reached the
expected state and the dmm_txn_commit() will return with an error code to
make sure that we are not continuing with a broken setup.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/omapdrm/omap_dmm_tiler.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
+++ b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
@@ -280,7 +280,12 @@ static int dmm_txn_commit(struct dmm_txn
 				msecs_to_jiffies(1)) <= 0) {
 			dev_err(dmm->dev, "timed out waiting for done\n");
 			ret = -ETIMEDOUT;
+			goto cleanup;
 		}
+
+		/* Check the engine status before continue */
+		ret = wait_status(engine, DMM_PATSTATUS_READY |
+				  DMM_PATSTATUS_VALID | DMM_PATSTATUS_DONE);
 	}
 
 cleanup: