[PATCH v1 3/3] ARM64 LPC: update binding doc

liviu.dudau at arm.com liviu.dudau at arm.com
Wed Jan 13 02:10:28 PST 2016


On Tue, Jan 12, 2016 at 11:52:48PM +0100, Arnd Bergmann wrote:
> On Tuesday 12 January 2016 15:13:35 liviu.dudau at arm.com wrote:
> > > int of_address_to_resource(struct device_node *dev, int index,
> > >                          struct resource *r)
> > > {
> > >       ...
> > >       /* flags can be get here, without ranges property reqired.
> > >        * if the reg = <0x0 0xe4 4>, I can get flag of IORESOURCE_MEM,
> > >        * if the reg = <0x1 0xe4 4>, I can get flag of IORESOURCE_IO,
> > 
> > That is strange, the parent node has #address-cells = <2> so the first two numbers should be part
> > of the address and not influence the flags. Can you add some debugging in of_get_address() and
> > try to figure out what bus is used in  *flags = bus->get_flags(prop) ?
> > 
> > 
> 
> This is the standard ISA binding. The first cell is the address space
> (IO or MEM), the second cell is the address within that space. This
> is similar to how PCI works.

OK, but from DT point of view and given the parent's #address-cells = <2> and #size-cells = <1>
should the reg not be something like reg = <0x1 0x0 0xe4 4> ?

Best regards,
Liviu

> 
> 	Arnd
> 

-- 
====================
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    ¯\_(ツ)_/¯



More information about the linux-arm-kernel mailing list