Read DT property to check if AXI DMA is connected to streaming IP
i.e axiethernet. If connected pass AXI4-Stream control words to
dma client using metadata_ops dmaengine API.
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xxxxxxxxxx>
---
Changes for v2:
- Use descriptor metadata API to pass control words to dma client.
- Rephrased commit description to be inline with implementation.
---
drivers/dma/xilinx/xilinx_dma.c | 37 +++++++++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
index 3aded7861fef..14dcfc473e52 100644
--- a/drivers/dma/xilinx/xilinx_dma.c
+++ b/drivers/dma/xilinx/xilinx_dma.c
@@ -491,6 +491,7 @@ struct xilinx_dma_config {
* @s2mm_chan_id: DMA s2mm channel identifier
* @mm2s_chan_id: DMA mm2s channel identifier
* @max_buffer_len: Max buffer length
+ * @has_axistream_connected: AXI DMA connected to AXI Stream IP
*/
struct xilinx_dma_device {
void __iomem *regs;
@@ -509,6 +510,7 @@ struct xilinx_dma_device {
u32 s2mm_chan_id;
u32 mm2s_chan_id;
u32 max_buffer_len;
+ bool has_axistream_connected;
};
/* Macros */
@@ -621,6 +623,29 @@ static inline void xilinx_aximcdma_buf(struct xilinx_dma_chan *chan,
}
}
+/**
+ * xilinx_dma_get_metadata_ptr- Populate metadata pointer and payload length
+ * @tx: async transaction descriptor
+ * @payload_len: metadata payload length
+ * @max_len: metadata max length
+ * Return: The app field pointer.
+ */
+static void *xilinx_dma_get_metadata_ptr(struct dma_async_tx_descriptor *tx,
+ size_t *payload_len, size_t *max_len)
+{
+ struct xilinx_dma_tx_descriptor *desc = to_dma_tx_descriptor(tx);
+ struct xilinx_axidma_tx_segment *seg;
+
+ *max_len = *payload_len = sizeof(u32) * XILINX_DMA_NUM_APP_WORDS;
+ seg = list_first_entry(&desc->segments,
+ struct xilinx_axidma_tx_segment, node);
+ return seg->hw.app;
+}
+
+static struct dma_descriptor_metadata_ops xilinx_dma_metadata_ops = {
+ .get_ptr = xilinx_dma_get_metadata_ptr,
+};
+
/* -----------------------------------------------------------------------------
* Descriptors and segments alloc and free
*/
@@ -2200,6 +2225,9 @@ static struct dma_async_tx_descriptor *xilinx_dma_prep_slave_sg(
segment->hw.control |= XILINX_DMA_BD_EOP;
}
+ if (chan->xdev->has_axistream_connected)
+ desc->async_tx.metadata_ops = &xilinx_dma_metadata_ops;
+
return &desc->async_tx;
error:
@@ -3032,6 +3060,11 @@ static int xilinx_dma_probe(struct platform_device *pdev)
}
}
+ if (xdev->dma_config->dmatype == XDMA_TYPE_AXIDMA) {
+ xdev->has_axistream_connected =
+ of_property_read_bool(node, "xlnx,axistream-connected");
+ }
+
if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) {
err = of_property_read_u32(node, "xlnx,num-fstores",
&num_frames);
@@ -3057,6 +3090,10 @@ static int xilinx_dma_probe(struct platform_device *pdev)
else
xdev->ext_addr = false;
+ /* Set metadata mode */
+ if (xdev->has_axistream_connected)
+ xdev->common.desc_metadata_modes = DESC_METADATA_ENGINE;
+
/* Set the dma mask bits */
dma_set_mask(xdev->dev, DMA_BIT_MASK(addr_width));
--
2.7.4
