[U-Boot-Users] [RFC][PATCH] fdt fixup

[Kumar Gala]

On Nov 2, 2007, at 10:47 AM, Grant Likely wrote:

> On 11/2/07, Sergej Stepanov <Sergej.Stepanov at ids.de> wrote:
>> Am Freitag, den 02.11.2007, 08:56 -0600 schrieb Grant Likely:
>>
>>> It also an area where device_type might actually be a useful  
>>> property
>>> if it is used to auto enumerate devices of the same type.  ie. If  
>>> the
>>> dtb doesn't explicitly specify eth* aliases, then u-boot could
>>> enumerate them so that generic fixup routines can be used and so  
>>> Linux
>>> (or other OS) can use the same device numbering as u-boot.
>>>
>> sorry...
>> in chosen-node select defaults, for example?
>
> I don't understand what you mean or are asking, but let me clarify  
> what I mean.
>
> I'm not talking about selected defaults; but about device enumeration
> (which is similar, but not exactly the same thing).  If there is a
> class of devices which is typically enumerated (like ethernet
> devices), then the device_type property *might* be useful because it
> would allow firmware to find all devices of a similar type and assign
> numbers to them.
>
> Also, OF has an 'aliases' mechanism defined which could be very
> useful.  The '/aliases' node contains a set of properties which assign
> a set of 'simple' names to the full path of a node.  For example, on
> the efika, /aliases looks like this:
>
> ok cd /aliases
> ok .properties
> name                  "aliases"
> eth                   "/builtin/ethernet"
> ok
>
> Now; for our purposes, using name->full_path mapping is probably
> sub-optimal and name->phandle might be better.  But regardless, the
> alias can be used as a shortcut to refer to a particular node.  For
> example, on the efika:
>
> ok cd /
> ok cd eth
> ok pwd
> /builtin at F0000000/ethernet at F0003000
> ok
>
> So, if the aliases node was populated with common names, or if u-boot
> could auto-populate the /aliases node with enumerated values for
> things like 'eth#' and 'serial#', then we could do something like this
> for fixups:

I dont see how u-boot could auto-populate, that seems to defeat the  
purpose of aliases.

- k