[U-Boot-Users] New version of AT91-Bootstrap forAT91SAM92xU-Boot/Buildroot/Linux users

Wolfgang Denk wd at denx.de
Mon Mar 26 13:42:24 CEST 2007

In message <00a001c76f77$382b4660$01c4af0a at Glamdring> you wrote:
> > Requiring to use "uclibc, NWFPE and a dynamic C library" for  such  a
> > piece of code seems fundamentally broken to me.
> The requirement is not that at91-bootstrap must use this.
> The requirement is that it is *able* to be built by this.

If you don't use feature F it should not get in your  way.  The  fact
that  I  have  installed  certain libraries here and there should not
matter as long as your linker step / script does not  pick  up  these

> I am using buildroot with extensions, and my requirement is that
> I want to have one single package, which can as output generate
> * Single Cross Compiler able to build all things below
> * Standalone NAND/Dataflash bootloader
> * U-Boot
> * Linux Kernel
> * Root File System

As meantioned a couple times before, U-Boot is self-contained, i.  e.
it  does  not  use any libraries from your development system, except
for those needed and provided by the C compiler. And if the  compiler
is sane, there should never be a coflict.

> The Linux kernel is built using NWFPE, uclibc and dynamic C library.

I doubt that the Linux *kernel* really uses any of these.

> Not including the C library routines memset, memcpy and div
> *forces* you to use the C library, and you cant have a dynamic loaded
> library in 4 kB, so it has to be static and thus it fails .

You continue to repeat that argument, and I  continue  to  not  being
able  to understand it. U-Boot *does* provide all these functions, so
why don't you just use these? We don't need no external C libraries.

> The NWFPE issue is with U-Boot.
> U-Boot cannot compile, since it has -msoftfloat hard-wired
> and this is really not neccessary. By removing the -msoftfloat
> you can compile using a NWFPE enabled compiler.

Why doesn't your NWFPE enabled compiler support this option?

> Due to dataflash sector boundaries, the natural size for U-Boot + Loader is
> 256 kB or less. I did not check the effect on U-Boot code size
> due to NWFPE enabled, but there should be little or none FPU code
> in U-Boot.

Consider any code that uses FP to be broken.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH, HRB 165235 Munich, CEO: Wolfgang Denk
Office:  Kirchenstr. 5,       D-82194 Groebenzell,            Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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