Re: [PATCH v3 2/4] remoteproc: imx_rpoc: fix carveout name parsing

On Thu, Jul 30, 2026 at 09:34:10AM -0700, Laurentiu Mihalcea wrote:
> From: Laurentiu Mihalcea <[email protected]>
>
> The imx remoteproc driver assumes that the names of the reserved memory
> regions reflect their usage (e.g. "vdevbuffer", "vdev0vring0", etc.). This
> conflicts with the devicetree specification's recommendation, which states
> that the names of the devicetree nodes should be generic.

This relies on a hidden ABI by parsing the remote node's name, and also
bypasses the DT binding check since there is no way to restrict the node
name of a memory region.

Frank
>
> Therefore, instead of relying on the node names, use the names passed via
> the "memory-region-names" property if present. Otherwise, keep the old
> behavior.
>
> The definition of imx_rproc_rmem_to_resource() is added to a common place
> as imx_dsp_rproc.c can also use it given that it suffers from the same
> aforementioned problem.
>
> Signed-off-by: Laurentiu Mihalcea <[email protected]>
> ---
>  drivers/remoteproc/imx_rproc.c | 13 +++++++++++--
>  drivers/remoteproc/imx_rproc.h | 21 +++++++++++++++++++++
>  2 files changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
> index 745ce52cd822..ce9bdfc1fa98 100644
> --- a/drivers/remoteproc/imx_rproc.c
> +++ b/drivers/remoteproc/imx_rproc.c
> @@ -643,7 +643,7 @@ static int imx_rproc_prepare(struct rproc *rproc)
>  		int err;
>  		struct resource res;
>
> -		err = of_reserved_mem_region_to_resource(np, i++, &res);
> +		err = imx_rproc_rmem_to_resource(np, i++, &res);
>  		if (err)
>  			break;
>
> @@ -818,11 +818,20 @@ static int imx_rproc_addr_init(struct imx_rproc *priv,
>  	if (nph <= 0)
>  		return 0;
>
> +	if (!of_property_present(np, "memory-region-names")) {
> +		dev_warn(dev, "using node names for carveouts should be avoided\n");
> +	} else {
> +		if (nph != of_property_count_strings(np, "memory-region-names")) {
> +			dev_err(dev, "invalid reserved memory name count\n");
> +			return -EINVAL;
> +		}
> +	}
> +
>  	/* remap optional addresses */
>  	for (a = 0; a < nph; a++) {
>  		struct resource res;
>
> -		err = of_reserved_mem_region_to_resource(np, a, &res);
> +		err = imx_rproc_rmem_to_resource(np, a, &res);
>  		if (err) {
>  			dev_err(dev, "unable to resolve memory region\n");
>  			return err;
> diff --git a/drivers/remoteproc/imx_rproc.h b/drivers/remoteproc/imx_rproc.h
> index 0d7d48352a10..3632bc375c71 100644
> --- a/drivers/remoteproc/imx_rproc.h
> +++ b/drivers/remoteproc/imx_rproc.h
> @@ -7,6 +7,8 @@
>  #ifndef _IMX_RPROC_H
>  #define _IMX_RPROC_H
>
> +#include <linux/of_reserved_mem.h>
> +
>  /* address translation table */
>  struct imx_rproc_att {
>  	u32 da;	/* device address (From Cortex M4 view)*/
> @@ -45,4 +47,23 @@ struct imx_rproc_dcfg {
>  	u32				reset_vector_mask;
>  };
>
> +static inline int imx_rproc_rmem_to_resource(struct device_node *np,
> +					     int index,
> +					     struct resource *res)
> +{
> +	int ret;
> +
> +	ret = of_reserved_mem_region_to_resource(np, index, res);
> +	if (ret)
> +		return ret;
> +
> +	/* "memory-region-names" is optional */
> +	ret = of_property_read_string_index(np, "memory-region-names",
> +					    index, &res->name);
> +	if (ret == -EINVAL)
> +		return 0;
> +
> +	return ret;
> +}
> +
>  #endif /* _IMX_RPROC_H */
> --
> 2.53.0
>