[PATCH v2] net/nfp: fix issue of data len exceeds descriptor limitation

[Ferruh Yigit]

On 11/29/2022 1:21 AM, Chaoyong He wrote:
> From: Long Wu <long.wu at corigine.com>
> 
> If dma_len is larger than NFDK_DESC_TX_DMA_LEN_HEAD, the value of
> dma_len bitwise and NFDK_DESC_TX_DMA_LEN_HEAD maybe less than packet
> head length and the packet will be dropped. Fill maximum dma_len in
> first tx descriptor to make sure the whole head is included in the
> first descriptor. In addition, add comments to better explain the
> code flow.
> 

updated patch title as:
net/nfp: fix Tx packet drop for large data length

> Fixes: c73dced48c8c ("net/nfp: add NFDk Tx")
> Cc: jin.liu at corigine.com
> Cc: stable at dpdk.org
> 
> Signed-off-by: Long Wu <long.wu at corigine.com>
> Reviewed-by: Niklas Söderlund <niklas.soderlund at corigine.com>

Applied to dpdk-next-net/main, thanks.


Below changes done while merging.

> +		/*
> +		 * We will do our best to pass as much data as we can in descriptor
> +		 * and we need to make sure the first descriptor includes whole
> +		 * head since there is limitation in firmware side. Sometimes the
> +		 * value of dma_len bitwise & NFDK_DESC_TX_DMA_LEN_HEAD will less
> +		 * than packet head len.
> +		 */

Updated last line as:
" * value of 'dma_len & NFDK_DESC_TX_DMA_LEN_HEAD' will be less "

<...>

>  
> +		/*
> +		 * The rest of the data (if any) will be in larger dma descritors

s/descritors/descriptors/
s/dma/DMA/