ioremap() on ISA memory space

Geert Uytterhoeven Geert.Uytterhoeven at
Wed Jun 9 04:28:48 EST 1999

I found one reason why current kernels don't work on my LongTrail: my NVRAM is
in ISA memory space. When the kernel tries to ioremap() it in
pmac_nvram_init(), I get

    __ioremap(): phys addr e0000 is RAM lr c000e43c

and ioremap() returns NULL, causing all later accesses to NVRAM (e.g. in atyfb)
to fail due to NULL pointer dereferences.

Do all CHRP boxes have NVRAM in ISA memory space? The comment (by Corey) near
the call to pmac_nvram_init() in chrp_init2() already wonders whether
pmac_nvram_init() should be called or not.

Besides, I'd say one must call ioremap() to access ISA memory space anyway, so
it sounds like a bug in the memory management subsystem to me.



Geert Uytterhoeven                     Geert.Uytterhoeven at
Wavelets, Linux/{m68k~Amiga,PPC~CHRP}
Department of Computer Science -- Katholieke Universiteit Leuven -- Belgium

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