Re: [PATCH] crypto: caam: map job ring registers without claiming region

[Richard Leitner <richard.leitner@linux.dev>]

Hi everybody,

just a friendly reminder that this patch is now on the mailing list for
14 days and was not included in the 2 rc's which were released since then.

As this essentially breaks CAAM on multiple i.MX SoC variants, is there
any possibility to get this included in v7.3-rc4?

Would be great :-)

Thanks!

regards;rl


On Mon, Sep 07, 2026 at 05:35:51PM +0200, Richard Leitner wrote:
> Hi Rosen,
> 
> On Tue, Sep 01, 2026 at 01:37:36PM -0700, Rosen Penev wrote:
> > devm_platform_ioremap_resource() ends up calling request_mem_region(),
> > which fails with -EBUSY on i.MX SoCs:
> > 
> > There the job rings are modelled as sub-regions of their parent
> > fsl,sec-v4.0 register window, and caam_probe() already reserves the
> > whole window exclusively via devm_of_iomap() before the children are
> > populated.  Every job ring therefore collides with its own parent and
> > fails to probe, taking the hardware RNG offline (seen on i.MX6, i.MX7
> > and i.MX8 boards such as colibri-imx7 and verdin-imx8mp).
> > 
> > Map the job ring registers with devm_ioremap() instead, which does not
> > claim the (already owned) region.
> > 
> > Fixes: 9a955c0a7d11 ("crypto: caam - simplify probe resource and IRQ handling")
> > Assisted-by: opencode:big-pickle
> > Signed-off-by: Rosen Penev <rosenp@gmail.com>
> 
> thanks for that fix!
> 
> Tested-by: Richard Leitner <richard.leitner@linux.dev> # i.MX8MP
> 
> regards;rl
> 
> > ---
> >  drivers/crypto/caam/jr.c | 23 ++++++++++++++++++++---
> >  1 file changed, 20 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
> > index f9e029945b51..2ed8229d4733 100644
> > --- a/drivers/crypto/caam/jr.c
> > +++ b/drivers/crypto/caam/jr.c
> > @@ -583,12 +583,29 @@ static int caam_jr_probe(struct platform_device *pdev)
> >  	struct caam_drv_private_jr *jrpriv;
> >  	static int total_jobrs;
> >  	void __iomem *ctrl;
> > +	struct resource *r;
> >  	int error;
> >  	int irq;
> >  
> > -	ctrl = devm_platform_ioremap_resource(pdev, 0);
> > -	if (IS_ERR(ctrl))
> > -		return PTR_ERR(ctrl);
> > +	/*
> > +	 * The job rings live inside the register window of their parent
> > +	 * fsl,sec-v4.0 node, which caam_probe() already reserves (and maps)
> > +	 * via devm_of_iomap().  A requested region that overlaps that
> > +	 * reservation, e.g. from devm_platform_ioremap_resource(), would
> > +	 * therefore fail with -EBUSY, so map the registers without claiming
> > +	 * the region here.
> > +	 */
> > +	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!r) {
> > +		dev_err(&pdev->dev, "platform_get_resource() failed\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	ctrl = devm_ioremap(&pdev->dev, r->start, resource_size(r));
> > +	if (!ctrl) {
> > +		dev_err(&pdev->dev, "devm_ioremap() failed\n");
> > +		return -ENOMEM;
> > +	}
> >  
> >  	irq = platform_get_irq(pdev, 0);
> >  	if (irq < 0)
> > -- 
> > 2.55.0
> > 
> >