i.MX consolidation patches

[s.hauer@pengutronix.de (Sascha Hauer)]

On Fri, Jun 03, 2011 at 02:17:02PM +0200, Wolfgang Denk wrote:
> Dear Sascha Hauer,
> 
> In message <20110603120258.GR23771@pengutronix.de> you wrote:
> >
> > > I'm not a friend of using magic values that are "totally-impossible".
> > > This is confusing, and here it is not needed.
> > 
> > I find using a field labelled 'entry point' and 'load address' as
> > absolute addresses or offsets into sdram depending on some flag
> > also quite confusing. btw how do you want to decide whether the
> > fields are offsets or absolute addresses? I see no flags field in
> > the uImage format.
> 
> I would define a new image type.  Instead of "-T kernel" we could for
> example use a new type "-T relkernel" to indicate that addresses are
> relative to start of system RAM.
> 
> > > If we could agree to interpret load address and entry point as
> > > offsets, the only remaining problem is to find out if we can use a
> > > common offset.
> > 
> > The zImages encapsulated in uImages are relocatable. So pick any offset
> > between 32k and 128MB into sdram like Russell explained. Higher values
> > are not desirable as this would break boards with less sdram.
> 
> What about the images without the preloader?  You know that U-Boot
> already provides all the needed code to perform the uncompressing, so
> it would be nice if we could avoid to include this into each and every
> image.  Is the raw kernel image, without the preloader, also
> relocatable and can be started at any address (keeping above
> restrictions in mind, of course)?

No, the raw image has to be started at
virt_to_phys(PAGE_OFFSET + TEXT_OFFSET) which is usually 32k into sdram.
Only some subarchs define it differently:

textofs-y := 0x00008000
textofs-$(CONFIG_ARCH_CLPS711X) := 0x00028000
textofs-$(CONFIG_PM_H1940)      := 0x00108000
textofs-$(CONFIG_SA1111) := 0x00208000

Sascha

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