Platform device style question

Ben Warren bwarren at qstreams.com
Fri Aug 25 04:43:12 EST 2006


Thanks Vitaly,

On Thu, 2006-08-24 at 22:06 +0400, Vitaly Bordug wrote:

> I'd suggest to make a look at LDD concerning linux device model...
Thanks.  I'll read it again.  My little brain absorbs this stuff very
slowly.
> For platform device, there's no need to cope with u-boot at all. You'll prolly need to 
> register the respective platform device from the board-specific code, with proper name 
> and driver's board-specific platform info. You may have a look at arch/ppc/syslib/ppc_sys.c about static
> PD definitions usage.

My particular platform (MPC8349) gets its hardware info (CPU, IMMBAR,
PCI, I2C, SPI resources etc.) from an OF device tree that is generated
alongside U-boot and I guess embedded in the uImage file.  (I apologize
if I'm getting my jargon mixed up here)  The OF device tree idea seemed
like a slick way to abstract away some HW settings from Linux.  I was
imagining writing board-side platform device registration that gets its
settings from the device tree, allowing a bit of re-use between similar
but not identical boards.
> 

> I'd make sense to figure out the platform device bus before digging into device trees. It's slightly 
> different stuff, for similar aim, but anyway... Actually you do not strictly need devtree to cope with 
> your case afaiu.

I definitely have much learning to do.  Thanks very much for the
pointers!

regards,
Ben




More information about the Linuxppc-embedded mailing list