[RFC POWERPC] booting-without-of: bindings for FHCI USB, GPIO LEDs, MCU, and NAND on UPM
Anton Vorontsov
cbouatmailru at gmail.com
Wed Apr 23 10:37:37 EST 2008
On Tue, Apr 22, 2008 at 03:50:22PM -0500, Josh Boyer wrote:
> On Tue, 2008-04-22 at 14:08 -0600, Grant Likely wrote:
> > On Tue, Apr 22, 2008 at 1:41 PM, Anton Vorontsov
> > <avorontsov at ru.mvista.com> wrote:
> > > Hi all,
> > > + w) NAND on UPM-driven Freescale Localbus
> > > +
> > > + Required properties:
> > > + - compatible : "fsl,upm-nand".
> > > + - reg : should specify localbus chip select and size used for the chip.
> > > + - width : should specify port size in bytes.
> > > + - fsl,upm-addr-offset : UPM pattern offset for the address latch.
> > > + - fsl,upm-cmd-offset : UPM pattern offset for the command latch.
> > > + - fsl,wait-pattern : should be present if NAND chip requires waiting
> > > + for Ready-Not-Busy pin after each executed pattern.
> > > + - fsl,wait-write : should be present if NAND chip needs waiting on
> > > + Ready-Not-Busy pin after each write cycle.
> > > + - linux,chip-delay : optional, may contain delay value in milliseconds
> > > + (in case when Ready-Not-Busy pin was unspecified).
> > > + - gpios : may specify optional GPIO connected to the Ready-Not-Busy pin.
> >
> > I'm not competent to comment on this binding; I haven't spent any time
> > looking at NAND binding conventions.
>
> That's because there are none, and every time someone proposes one it's
> like this. Full of weird $board specific stuff that have nothing to do
> with the actual NAND chip.
>
> For example, why is fsl,wait-write defined as an fsl specific property?
> It seems generic to the NAND chip itself. Also, why in the example is
> the specific NAND chip part number listed, followed by fsl,upm-nand?
> It's almost as if people want to mix the NAND chip and NAND controller
> definitions together. Maybe there is a good reason for it, but it's
> really confusing.
Much thanks for the idea, I should indeed separate UPM NAND controller
and NAND chip itself.
--
Anton Vorontsov
email: cbouatmailru at gmail.com
irc://irc.freenode.net/bd2
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