Re: [PATCH V2 3/5] dmaengine: xilinx_dma: Extend metadata handling for AXI MCDMA

[Frank Li]

On Fri, Mar 13, 2026 at 11:55:31AM +0530, Srinivas Neeli wrote:
> From: Suraj Gupta <suraj.gupta2@xxxxxxx>
>
> Extend probe logic to detect AXI Stream connections for MCDMA. When
> an AXI Stream interface is present, metadata operations are enabled for
> the MCDMA channel. The xilinx_dma_get_metadata_ptr() is enhanced to
> retrieve metadata directly from MCDMA descriptors.

Need extra empty line between paragraph

> Add corresponding channel reference in struct xilinx_dma_tx_descriptor to
> retrieve associated channel.
> These changes ensure proper metadata handling and accurate transfer
> size reporting for MCDMA transfers.
>
> Signed-off-by: Suraj Gupta <suraj.gupta2@xxxxxxx>
> Co-developed-by: Srinivas Neeli <srinivas.neeli@xxxxxxx>
> Signed-off-by: Srinivas Neeli <srinivas.neeli@xxxxxxx>
> ---
>  drivers/dma/xilinx/xilinx_dma.c | 30 +++++++++++++++++++++++++-----
>  1 file changed, 25 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c
> index 00200b4c2372..52203d44e7a4 100644
> --- a/drivers/dma/xilinx/xilinx_dma.c
> +++ b/drivers/dma/xilinx/xilinx_dma.c
> @@ -222,6 +222,8 @@
>  #define XILINX_MCDMA_BD_EOP			BIT(30)
>  #define XILINX_MCDMA_BD_SOP			BIT(31)
>
> +struct xilinx_dma_chan;
> +
>  /**
>   * struct xilinx_vdma_desc_hw - Hardware Descriptor
>   * @next_desc: Next Descriptor Pointer @0x00
> @@ -371,6 +373,7 @@ struct xilinx_cdma_tx_segment {
>
>  /**
>   * struct xilinx_dma_tx_descriptor - Per Transaction structure
> + * @chan: DMA channel for which this descriptor is allocated
>   * @async_tx: Async transaction descriptor
>   * @segments: TX segments list
>   * @node: Node in the channel descriptors list
> @@ -379,6 +382,7 @@ struct xilinx_cdma_tx_segment {
>   * @residue: Residue of the completed descriptor
>   */
>  struct xilinx_dma_tx_descriptor {
> +	struct xilinx_dma_chan *chan;

async_tx already include dma_chan's information.

Frank