Accessing IO space via resources

Michel Lanners mlan at
Sat Jun 24 16:32:04 EST 2000

Hi all,

On  23 Jun, this message from To: linuxppc-dev at echoed through cyberspace:
> Now, in the latest 2.4.0-ac kernels, ioremap() returns different
> addresses, not 1:1 the original address anymore. And of course this
> breaks the above scheme. (I've not looked into why this is so... I
> suppose it's not a bug?)

After investigating this, it turns out that early in the boot process,
before the mm system is up, ioremap returns virt == phys for
addresses >= ioremap_base. ioremap_base got changed from 0xf8000000 to
0xf0000000 in recent kernels. Anybody kow why this got changed?

Obviously, the PCI IO space was above ioremap_base before, but is below


Michel Lanners                 |  " Read Philosophy.  Study Art.
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