[PATCH 01/17] of: add dma-mask binding

[Jean-Christophe PLAGNIOL-VILLARD]

On 21:55 Tue 13 Nov     , Rob Herring wrote:
> On 11/12/2012 02:52 AM, Wenyou Yang wrote:
> > From: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
> > 
> > This will allow each device to specify its dma-mask for this we use the
> > coherent_dma_mask as pointer. By default the dma-mask will be set to
> > DMA_BIT_MASK(32).
> 
> Do you really have a use case this is not DMA_BIT_MASK(32)?
yes as exmample on 64bit platfrom it will be 64 on x86 it's also 24, on power
pc 40
> 
> > The microblaze architecture hook is drop
> > 
> > Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
> > Cc: grant.likely at secretlab.ca
> > Cc: rob.herring at calxeda.com
> > Cc: devicetree-discuss at lists.ozlabs.org
> > ---
> >  drivers/of/platform.c |   23 ++++++++++++++++-------
> >  1 file changed, 16 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > index b80891b..31ed405 100644
> > --- a/drivers/of/platform.c
> > +++ b/drivers/of/platform.c
> > @@ -130,6 +130,21 @@ void of_device_make_bus_id(struct device *dev)
> >  	dev_set_name(dev, "%s.%d", node->name, magic - 1);
> >  }
> >  
> > +static void of_get_dma_mask(struct device *dev, struct device_node *np)
> > +{
> > +	const __be32 *prop;
> > +	int len;
> > +
> > +	prop = of_get_property(np, "dma-mask", &len);
> 
> dma-ranges may work for this purpose.
> 
> > +
> > +	dev->dma_mask = &dev->coherent_dma_mask;
> 
> I don't really know, but I suspect this is wrong.
no this is correct was suggest by Russell
we already do so on other ARM or SH as example

the dma expect a pointer for dma_mask but the value is the same as coherent
> 
> > +
> > +	if (!prop)
> > +		dev->coherent_dma_mask = DMA_BIT_MASK(32);
> > +	else
> > +		dev->coherent_dma_mask = of_read_number(prop, len / 4);
> > +}
> > +
> >  /**
> >   * of_device_alloc - Allocate and initialize an of_device
> >   * @np: device node to assign to device
> > @@ -171,10 +186,8 @@ struct platform_device *of_device_alloc(struct device_node *np,
> >  		WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq);
> >  	}
> >  
> > +	of_get_dma_mask(&dev->dev, np);
> >  	dev->dev.of_node = of_node_get(np);
> > -#if defined(CONFIG_MICROBLAZE)
> > -	dev->dev.dma_mask = &dev->archdata.dma_mask;
> > -#endif
> >  	dev->dev.parent = parent;
> >  
> >  	if (bus_id)
> > @@ -211,10 +224,6 @@ struct platform_device *of_platform_device_create_pdata(
> >  	if (!dev)
> >  		return NULL;
> >  
> > -#if defined(CONFIG_MICROBLAZE)
> > -	dev->archdata.dma_mask = 0xffffffffUL;
> > -#endif
> > -	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
> >  	dev->dev.bus = &platform_bus_type;
> >  	dev->dev.platform_data = platform_data;
> >  
> >