[PATCH 1/1] [MTD/NAND]: Add Blackfin BF52x on-chip NAND Flash controller driver support in bf5xx_nand driver

Robin Getz rgetz at blackfin.uclinux.org
Sat Nov 24 08:11:35 EST 2007


On Sat 24 Nov 2007 02:15, Bryan Wu pondered:
> On Nov 24, 2007 2:43 PM, David Woodhouse <dwmw2 at infradead.org> wrote:
> >
> > On Fri, 2007-11-23 at 17:04 -0500, Robin Getz wrote:
> > > It could be a runtime if() but we don't currently have the is_mach() all
> > > set up properly today.
> > >
> > > This is because on most systems that Blackfin ships on - memory is the
> > > dominate cost of the system, and end users don't want to take the either
> > > the storage (flash) hit of having code they don't use, or the run time
> > > (DRAM) overhead. They are fine with compiling 2 kernels for two
> > > platforms if it means things are cheaper. :)
> > >
> > > That being said, we still need to go back, and add things properly - and
> > > just let gcc optimise things away if it is not used - c code is more
> > > maintainable than all the ifdefs we have today.
> > >
> > > This is the goal - it will just take a little bit to get there.
> >
> > For now I suspect you could at least define machine_is_bf52x() and
> > machine_is_bf54x() which are hard-coded to either zero or one according
> > to the configuration, and at least you wouldn't need to add ifdefs to
> > drivers.
> >
> 
> We got some plan to do this, but maybe cpu_is_bf52x() and
> cpu_is_bf54x() are better.

Which was one of the reasons I think we were waiting/confused. There doesn't 
seem to be any consistancy between:

cpu_is_

which I assume refers to specific processor/chipset/SoC implementation?
cpu_is_ixp42x
cpu_is_ixp43x
cpu_is_ixp46x

mach_is_

which I assume refers to a specific platform:

mach_is_dreamcast
mach_is_hp6xx
mach_is_r7780mp
mach_is_r7780rp

machine_is_xxxx

which I assume refers to a specific platform:

machine_is_jornada56x
machine_is_jornada720
machine_is_nokia770

So, we should use cpu_is_ as Bryan suggested?

-Robin



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