Messages in this thread | | | Subject | Re: [PATCH] 2.5.17 /dev/port | Date | Thu, 23 May 2002 02:59:33 +0100 (BST) | From | Alan Cox <> |
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> On non-Intel platforms, with no dedicated IOIO opcodes, IOIO is > usually implemented as a specific memory range. In that case, the > only way to allow user-space access to it would be to mmap() that > range... which means iopl() inb() and outb() on those platforms might > be implemented either as open, readp and writep, respectively, or by > iopl() being open() followed by mmap().
mmap and some other logic in certain cases. An outb stalls until the I/O hits the device even on PCI. Either way thats really about what you put into /dev/port (either the i/o logic or a map of /dev/mem with slightly tweaked args) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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