Re: [PATCH v3 1/2] remoteproc: Fall back to using parent memory pool if no dedicated available

[Arnaud POULIQUEN <arnaud.pouliquen@st.com>]

Hi Suman

On 4/20/20 6:05 PM, Suman Anna wrote:
> From: Tero Kristo <t-kristo@ti.com>
> 
> In some cases, like with OMAP remoteproc, we are not creating dedicated
> memory pool for the virtio device. Instead, we use the same memory pool
> for all shared memories. The current virtio memory pool handling forces
> a split between these two, as a separate device is created for it,
> causing memory to be allocated from bad location if the dedicated pool
> is not available. Fix this by falling back to using the parent device
> memory pool if dedicated is not available.

As it fixes the implementation of the legacy, that seems reasonable to me.
 
Acked-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>

> 
> Fixes: 086d08725d34 ("remoteproc: create vdev subdevice with specific dma memory pool")
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> Signed-off-by: Suman Anna <s-anna@ti.com>
> ---
> v3:
>  - Go back to v1 logic (removed the vdevbuf_mem_id variable added in v2)
>  - Revised the comment to remove references to vdevbuf_mem_id
>  - Capitalize the patch header
> v2: https://patchwork.kernel.org/patch/11447651/
> 
>  drivers/remoteproc/remoteproc_virtio.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/remoteproc/remoteproc_virtio.c b/drivers/remoteproc/remoteproc_virtio.c
> index e61d738d9b47..44187fe43677 100644
> --- a/drivers/remoteproc/remoteproc_virtio.c
> +++ b/drivers/remoteproc/remoteproc_virtio.c
> @@ -376,6 +376,18 @@ int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
>  				goto out;
>  			}
>  		}
> +	} else {
> +		struct device_node *np = rproc->dev.parent->of_node;
> +
> +		/*
> +		 * If we don't have dedicated buffer, just attempt to re-assign
> +		 * the reserved memory from our parent. A default memory-region
> +		 * at index 0 from the parent's memory-regions is assigned for
> +		 * the rvdev dev to allocate from. Failure is non-critical and
> +		 * the allocations will fall back to global pools, so don't
> +		 * check return value either.
> +		 */
> +		of_reserved_mem_device_init_by_idx(dev, np, 0);
>  	}
>  
>  	/* Allocate virtio device */
>