[0/1] Add support for metadata in bam_dma

Message

Sireesh Kodali Sept. 19, 2021, 2:33 p.m. UTC

IPA v2.x uses BAM to send and receive IP packets, to and from the AP.
However, unlike its predecessor BAM-DMUX, it doesn't send information
about the packet length. To find the length of the packet, one must
instead read the bam_desc metadata. This patch adds support for sending
the size metadata over the dmaengine metadata api. Currently only the
dma size is stored in the metadata. Only client-side metadata is
supported for now, because host-side metadata doesn't make sense for
IPA, where more than one DMA descriptors could be waiting to be acked
and processed.

Sireesh Kodali (1):
  dmaengine: qcom: bam_dma: Add support for metadata

 drivers/dma/qcom/bam_dma.c | 74 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)

Comments

Sireesh Kodali Sept. 19, 2021, 3:52 p.m. UTC | #1

Hi,

Sorry, I accidentally sent this patch twice. Please ignore the second one
(i.e. the one I'm replying to now)

lkml link to original: https://lkml.org/lkml/2021/9/19/126

Sorry for the inconvenience
Sireesh



On Sun, Sep 19, 2021 at 8:03 PM Sireesh Kodali <[e-mail]> wrote:
>
> IPA v2.x uses BAM to send and receive IP packets, to and from the AP.
> However, unlike its predecessor BAM-DMUX, it doesn't send information
> about the packet length. To find the length of the packet, one must
> instead read the bam_desc metadata. This patch adds support for sending
> the size metadata over the dmaengine metadata api. Currently only the
> dma size is stored in the metadata. Only client-side metadata is
> supported for now, because host-side metadata doesn't make sense for
> IPA, where more than one DMA descriptors could be waiting to be acked
> and processed.
>
> Sireesh Kodali (1):
>   dmaengine: qcom: bam_dma: Add support for metadata
>
>  drivers/dma/qcom/bam_dma.c | 74 ++++++++++++++++++++++++++++++++++++++
>  1 file changed, 74 insertions(+)
>
> --
> 2.33.0
>