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From:   Jan Kuliga <jankul@alatek.krakow.pl>
To:     lizhi.hou@amd.com, brian.xu@amd.com, raj.kumar.rampelli@amd.com,
        vkoul@kernel.org, michal.simek@amd.com, dmaengine@vger.kernel.org,
        linux-kernel@vger.kernel.org, miquel.raynal@bootlin.com
Cc:     jankul@alatek.krakow.pl
Subject: [PATCH v4 6/8] dmaengine: xilinx: xdma: Add transfer error reporting
Date:   Fri,  8 Dec 2023 14:49:27 +0100
Message-Id: <20231208134929.49523-7-jankul@alatek.krakow.pl>
In-Reply-To: <20231208134838.49500-1-jankul@alatek.krakow.pl>
References: <20231208134838.49500-1-jankul@alatek.krakow.pl>
MIME-Version: 1.0
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Extend the capability of transfer status reporting. Introduce error flag,
which allows to report error in case of a interrupt-reported error
condition.

Signed-off-by: Jan Kuliga <jankul@alatek.krakow.pl>
---
 drivers/dma/xilinx/xdma.c | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/drivers/dma/xilinx/xdma.c b/drivers/dma/xilinx/xdma.c
index d1bc36133a45..dbde6905acc7 100644
--- a/drivers/dma/xilinx/xdma.c
+++ b/drivers/dma/xilinx/xdma.c
@@ -85,6 +85,7 @@ struct xdma_chan {
  * @cyclic: Cyclic transfer vs. scatter-gather
  * @periods: Number of periods in the cyclic transfer
  * @period_size: Size of a period in bytes in cyclic transfers
+ * @error: tx error flag
  */
 struct xdma_desc {
 	struct virt_dma_desc		vdesc;
@@ -97,6 +98,7 @@ struct xdma_desc {
 	bool				cyclic;
 	u32				periods;
 	u32				period_size;
+	bool				error;
 };

 #define XDMA_DEV_STATUS_REG_DMA		BIT(0)
@@ -274,6 +276,7 @@ xdma_alloc_desc(struct xdma_chan *chan, u32 desc_num,=
 bool cyclic)
 	sw_desc->chan =3D chan;
 	sw_desc->desc_num =3D desc_num;
 	sw_desc->cyclic =3D cyclic;
+	sw_desc->error =3D false;
 	dblk_num =3D DIV_ROUND_UP(desc_num, XDMA_DESC_ADJACENT);
 	sw_desc->desc_blocks =3D kcalloc(dblk_num, sizeof(*sw_desc->desc_blocks=
),
 				       GFP_NOWAIT);
@@ -770,20 +773,20 @@ static enum dma_status xdma_tx_status(struct dma_ch=
an *chan, dma_cookie_t cookie
 	spin_lock_irqsave(&xdma_chan->vchan.lock, flags);

 	vd =3D vchan_find_desc(&xdma_chan->vchan, cookie);
-	if (vd)
-		desc =3D to_xdma_desc(vd);
-	if (!desc || !desc->cyclic) {
-		spin_unlock_irqrestore(&xdma_chan->vchan.lock, flags);
-		return ret;
-	}
-
-	period_idx =3D desc->completed_desc_num % desc->periods;
-	residue =3D (desc->periods - period_idx) * desc->period_size;
+	if (!vd)
+		goto out;

+	desc =3D to_xdma_desc(vd);
+	if (desc->error) {
+		ret =3D DMA_ERROR;
+	} else if (desc->cyclic) {
+		period_idx =3D desc->completed_desc_num % desc->periods;
+		residue =3D (desc->periods - period_idx) * desc->period_size;
+		dma_set_residue(state, residue);
+	}
+out:
 	spin_unlock_irqrestore(&xdma_chan->vchan.lock, flags);

-	dma_set_residue(state, residue);
-
 	return ret;
}

@@ -808,6 +811,7 @@ static irqreturn_t xdma_channel_isr(int irq, void *de=
v_id)
 	vd =3D vchan_next_desc(&xchan->vchan);
 	if (!vd)
 		goto out;
+	desc =3D to_xdma_desc(vd);

 	desc =3D to_xdma_desc(vd);
 	xdev =3D xchan->xdev_hdl;
@@ -820,6 +824,7 @@ static irqreturn_t xdma_channel_isr(int irq, void *de=
v_id)
 	st &=3D XDMA_CHAN_STATUS_MASK;
 	if ((st & XDMA_CHAN_ERROR_MASK) ||
 		!(st & (CHAN_CTRL_IE_DESC_COMPLETED | CHAN_CTRL_IE_DESC_STOPPED))) {
+		desc->error =3D true;
 		xdma_err(xdev, "channel error, status register value: 0x%x", st);
 		goto out;
 	}
--
2.34.1