[PATCH V2 5/5] remoteproc: imx_rproc: change to ioremap_wc for dram

[Peng Fan]

Hi Mathieu,

> Subject: Re: [PATCH V2 5/5] remoteproc: imx_rproc: change to ioremap_wc
> for dram
> 
> On Wed, Jul 07, 2021 at 05:40:33PM +0800, Dong Aisheng wrote:
> > DRAM is not io memory, so changed to ioremap_wc. This is also aligned
> > with core io accessories. e.g. memcpy/memset and cpu direct access.
> >
> > Cc: Bjorn Andersson <bjorn.andersson at linaro.org>
> > Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
> > Fixes: 5e4c1243071d ("remoteproc: imx_rproc: support remote cores
> > booted before Linux Kernel")
> > Reviewed-by: Peng Fan <peng.fan at nxp.com>
> > Signed-off-by: Dong Aisheng <aisheng.dong at nxp.com>
> > ---
> > v1->v2:
> >  * new patch
> 
> It's a new patch and yet Peng's RB tag is already on it...

Aisheng's reply in the other email.
"
Above two lines were added by mistake. (copied from patch 4)
I'm going to wait for review comments first and resend with changes if any.

Regards
Aisheng
"

> 
> > ---
> >  drivers/remoteproc/imx_rproc.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/remoteproc/imx_rproc.c
> > b/drivers/remoteproc/imx_rproc.c index ff620688fad9..4ae416ba5080
> > 100644
> > --- a/drivers/remoteproc/imx_rproc.c
> > +++ b/drivers/remoteproc/imx_rproc.c
> > @@ -597,7 +597,7 @@ static int imx_rproc_addr_init(struct imx_rproc
> *priv,
> >  			break;
> >
> >  		/* Not use resource version, because we might share region */
> > -		priv->mem[b].cpu_addr = devm_ioremap(&pdev->dev, res.start,
> resource_size(&res));
> > +		priv->mem[b].cpu_addr = devm_ioremap_wc(&pdev->dev,
> res.start,
> > +resource_size(&res));
> 
> How was it working before?  

we took all memory used by M-core as io memory, including TCM/SRAM/DRAM.

Will it really work for all platforms and was this
> extensively tested?

Aisheng may confirm, I not test this patchset.

> 
> Peng - I will need an explicit reply from you that you are in agreement with
> this change. 

I not test, but it should work per my understanding.
i.MX TCM area has limitation that not use ioremap_wc, DRAM has no such
limitation. Just think this not deserve a fix tag.

> I will also need you to review patch 01 and 02 of this set.

Sure, I'll review.

Thanks,
Peng.

> 
> Thanks,
> Mathieu
> 
> >  		if (!priv->mem[b].cpu_addr) {
> >  			dev_err(dev, "failed to remap %pr\n", &res);
> >  			return -ENOMEM;
> > --
> > 2.25.1
> >