Messages in this thread | | | Date | Tue, 11 Dec 2012 17:32:32 +0000 | From | Alan Cox <> | Subject | Re: [RFC v1 01/16] lib: devres: don't enclose pcim_*() functions in CONFIG_HAS_IOPORT |
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> with it. It's very simple. The IO port space is for ISA/PCMCIA and > PCI IO port regions. It is nothing more than that.
And on a lot of devices the LPC bus.
> Plus, if you _have_ IO space support, you must have some MMIO region for > them to target - doing what many platforms have done to date and targetted > ISA IO address 0 at virtual address 0 is just not on because as soon as > you build a device driver which probes ISA addresses into your kernel, > you will oops.
There shouldn't really be anything poking around that is modern - this is true of some PC stuff too.
In general however if its because you have a window partly mapped you could just catch the exception and load 0xFF for reads (and probably whine with a backtrace so you know who to moan at).
Alan
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