Re: [PATCH v5] remoteproc: Use of_reserved_mem_region_* functions for "memory-region"

From: Daniel Baluta
Date: Wed Aug 20 2025 - 04:23:00 EST


Hi Rob,

This patch will break IMX RPROC support.
<snip>

> --- a/drivers/remoteproc/imx_rproc.c
> +++ b/drivers/remoteproc/imx_rproc.c

<snip>
> static int imx_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
<snip>

> - priv->mem[b].cpu_addr = devm_ioremap_wc(&pdev->dev, res.start, resource_size(&res));
> + priv->mem[b].cpu_addr = devm_ioremap_resource_wc(&pdev->dev, &res);

devm_ioremap_resource_wc works only for IORESOURCE_MEM resources:

lib/devres.c:124
static void __iomem *
__devm_ioremap_resource(struct device *dev, const struct resource *res,

» if (!res || resource_type(res) != IORESOURCE_MEM) {
» » ret = dev_err_probe(dev, -EINVAL, "invalid resource
%pR\n", res);
» » return IOMEM_ERR_PTR(ret);
» }

while the devm_ioremap_wc doesn't care about this.

So we cannot use devm_ioremap_resource_wc here unless you add
IORESOURCE_MEM flags
to of_reserved_mem_region_to_resource as discussed here:

https://lkml.org/lkml/2025/4/28/759

The same issue we are already experiencing with Sound Open Firmware
where the change was already merged
and we have a bug already reported.

How should we fix this:

1) Add res->flags = IORESOURCE_MEM; in of_reserved_mem_region_to_resource

OR

2) Use devm_ioremap_wc instead of devm_ioremap_resource_wc.

thanks,
Daniel.



Daniel.