Re: Query: DMA device assigned to remoteproc usage by Linux

From: Mukesh Ojha
Date: Mon Jan 20 2025 - 01:39:42 EST


On Mon, Dec 23, 2024 at 11:27 PM Mukesh Ojha
<mukesh.ojha@xxxxxxxxxxxxxxxx> wrote:
>
> Hi All,
>
> Wanted to check if we have encountered remoteproc use case where a device
> with dma is assigned to a remoteproc with its own streamid and iommu
> translation context. This DMA device can have a selective DMA range
> within the remoteproc carveout memory that needs to be iommu mapped
> before the remoteproc is up.
>
> Do we have any example in remoteproc that handles such scenario where
> device dma (assigned to remoteproc) has its iommu setup by Linux (since
> the iommu is under its control) ?
>
> I was exploring some of the remoteproc drivers but did not find anything
> close to DMA use case and from where remoteproc should get this ddr range ?
>
> device tree ? or rsc table ? if rsc table then which among the below ?

Resurfacing this in case it was missed during the New Year vacation period.

-Mukesh
>
> enum fw_resource_type {
> RSC_CARVEOUT = 0,
> RSC_DEVMEM = 1,
> RSC_TRACE = 2,
> RSC_VDEV = 3,
> RSC_LAST = 4,
> RSC_VENDOR_START = 128,
> RSC_VENDOR_END = 512,
>
>
> -Mukesh