RE: [PATCH 03/10] remoteproc: imx: use devm_ioremap

[Peng Fan <peng.fan@nxp.com>]

Hi Oleksij,

> Subject: Re: [PATCH 03/10] remoteproc: imx: use devm_ioremap
> 
> On Fri, Jul 24, 2020 at 04:08:06PM +0800, Peng Fan wrote:
> > We might need to map an region multiple times, becaue the region might
> > be shared between remote processors, such i.MX8QM with dual M4 cores.
> > So use devm_ioremap, not devm_ioremap_resource.
> 
> Can you please give an example of this kind of shared resources and how they
> should be handled by two separate devices?

This is to share vdevbuffer space, there is a vdevbuffer in device tree, it will be
shared between M4_0 and M4_1.

For the buffer, it is Linux DMA API will handle the space.

Thanks,
Peng.

> 
> > Reviewed-by: Richard Zhu <hongxing.zhu@nxp.com>
> > Signed-off-by: Peng Fan <peng.fan@nxp.com>
> > ---
> >  drivers/remoteproc/imx_rproc.c | 5 +++--
> >  1 file changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/remoteproc/imx_rproc.c
> > b/drivers/remoteproc/imx_rproc.c index 3b3904ebac75..82594a800a1b
> > 100644
> > --- a/drivers/remoteproc/imx_rproc.c
> > +++ b/drivers/remoteproc/imx_rproc.c
> > @@ -296,9 +296,10 @@ static int imx_rproc_addr_init(struct imx_rproc
> *priv,
> >  		if (b >= IMX7D_RPROC_MEM_MAX)
> >  			break;
> >
> > -		priv->mem[b].cpu_addr = devm_ioremap_resource(&pdev->dev,
> &res);
> > +		/* Not use resource version, because we might share region*/
> > +		priv->mem[b].cpu_addr = devm_ioremap(&pdev->dev, res.start,
> > +resource_size(&res));
> >  		if (IS_ERR(priv->mem[b].cpu_addr)) {
> > -			dev_err(dev, "devm_ioremap_resource failed\n");
> > +			dev_err(dev, "devm_ioremap %pR failed\n", &res);
> >  			err = PTR_ERR(priv->mem[b].cpu_addr);
> >  			return err;
> >  		}
> > --
> > 2.16.4
> >
> >
> 
> --
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