use IORESOURCE_REG resource type for non-translatable addresses in DT
Arnd Bergmann
arnd at arndb.de
Tue Jul 29 05:00:50 PDT 2014
On Tuesday 29 July 2014 14:42:31 Stanimir Varbanov wrote:
> taddr = of_translate_address(dev, addrp);
> - if (taddr == OF_BAD_ADDR)
> - return -EINVAL;
> + /*
> + * if the address is non-translatable to cpu physical address
> + * fallback to a IORESOURCE_REG resource.
> + */
> + if (taddr == OF_BAD_ADDR) {
> + memset(r, 0, sizeof(*r));
> + taddr = of_read_number(addrp, 1);
> + if (taddr == OF_BAD_ADDR)
> + return -EINVAL;
> + r->start = taddr;
> + r->end = taddr + size - 1;
> + r->flags = IORESOURCE_REG;
> + r->name = name ? name : dev->full_name;
> + return 0;
> + }
> +
I don't think that everything returning OF_BAD_ADDR makes sense
to turn into IORESOURCE_REG. It could be an e.g. invalid DT
representation, a node with #size-cells=<0>, or it could be
something that gets translated one or more nodes up in the
tree before it reaches a bus without a ranges property.
Also, you should not rely on #address-cells being hardcoded
to <1> above.
How about modifying of_get_address() rather than
__of_address_to_resource() instead? You could introduce
a new of_bus entry for each bus you expect to return
an IORESOURCE_REG, or you could change of_bus_default_get_flags
to return IORESOURCE_REG if the parent node has no ranges property
and is not the root node.
Arnd
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