Messages in this thread | | | From | Roland Dreier <> | Subject | Re: howto use ioremap_wc? | Date | Wed, 04 Jun 2008 21:53:54 -0700 |
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This thread reminds me of another question about interfaces for using PAT. Are there any plans for making pgprot_writecombine() a generic interface that portable drivers can use to map PCI memory into userspace with WC turned on? (Falling back to uncached when WC is not available for whatever reason is fine for the case I have in mind)
Maybe it's better to ask at a higher level: what's the right thing for a driver to do in an mmap method when it wants to expose PCI memory to userspace with WC turned on if possible? I see that the PCI sysfs code on x86 does it using non-exported (hence not available to a driver buildable as a module) interfaces.
Thanks, Roland
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