On Mon, Jul 04, 2011 at 04:32:35PM -0400, Christopher Harvey wrote:
> On Mon, Jul 04, 2011 at 04:13:49PM -0400, Jason wrote:
> > On Mon, Jul 04, 2011 at 02:55:54PM -0400, Christopher Harvey wrote:
> > > On Mon, Jul 04, 2011 at 02:08:44PM -0400, Jason wrote:
> > > > On Mon, Jul 04, 2011 at 01:45:41PM -0400, Christopher Harvey wrote:
> > > > > + Hopefully there will never be this many machines.
> > > > > + Can't use 0 since 0 is already used as a mach-type. */
> > > > > + gd->bd->bi_arch_number = 0xffffffff;
> > > > >
> > > > > gd->bd->bi_baudrate = gd->baudrate;
> > > > > /* Ram ist board specific, so move it to board code ... */
> > > > > diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
> > > > > index 802e833..70b3b76 100644
> > > > > --- a/arch/arm/lib/bootm.c
> > > > > +++ b/arch/arm/lib/bootm.c
> > > > > @@ -113,6 +113,12 @@ int do_bootm_linux(int flag, int argc, char
> > > > > *argv[], bootm_headers_t *images)
> > > > > printf ("Using machid 0x%x from environment\n", machid);
> > > > > }
> > > > >
> > > > > +#ifdef DEBUG
> > > > > + if(machid==0xffffffff) {
> > > > > + debug("\nWarning: machid not set! Linux will not finish
> > > > > booting.\n\n");
> > > >
> > > > s/finish/start/ ;-)
> > > >
> > > I'll have to disagree here. Linux will decompress and some functions
> > > will run but it will eventually stop, hence will not finish.
> >
> > On further investigation, you're right, it doesn't finish
> > starting/booting. Sorry for the noise.
> >
> > > > Also, shouldn't the compile fail in this case (#error)? Or, at least
> > > > #warn?
> > > >
> > > The compiler can't know what machid will be at runtime. Maybe a "would
> > > you like to continue?" prompt could work.
> >
> > Since the kernel throws a nice fat error message when the MACH_TYPE
> > doesn't match what it was compiled for, I don't see the point to adding
> > another message at the same point in the development process.
>
> I didn't see that message. Do you know what lines of code in the
> kernel print it? Or maybe just the message itself?
In init/main.c
start_kernel() calls
setup_arch()
In arch/arm/kernel/setup.c
setup_arch() calls
setup_machine_tags() which calls
dump_machine_table()
when the value in r1 doesn't match any of the mach-types the kernel was
compiled for.
> If the kernel can check the value why would it need to be passed
> in the first place?
Because the kernel has no way of easily determining which arm board it's
running on without this feature.
hth,
Jason.
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
http://lists.denx.de/mailman/listinfo/u-boot
