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Re: device tree for arm soc ?

On Sun, Sep 22, 2013 at 02:27:38PM -0600, Warner Losh wrote:
> On Sep 21, 2013, at 1:05 PM, Manuel Bouyer wrote:
> > Linux solved this by providing a device tree at boot time, which describe
> > the hardware including the device to I/O ping associations.
> > The device tree file is loaded at the same time as the kernel by the
> > boot loader. FreeBSD has also gone this route. Of course they're not
> > using the same DT ...
> The goal in FreeBSD land is to use the same DT. We're just not there yet, so 
> some boards need custom FDTs to compensate for those DTs that violate the 
> OpenFirmware mantra that the DT just describes hardware and allows too many 
> linuxisms to creep in...

Can you give details about these linuxism ? i only looked at the FDT for
beaglebone from both side at this time, and they indeed look very different.
Linux uses lots of "magic numbers" while freebsd seems to use the board's pin
names ... 
> Warner

Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference

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