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Re: PCI BAR's prefetchable bit and pci_mapreg_map()

On Wed, 22 Mar 2017, Manuel Bouyer wrote:

On Wed, Mar 22, 2017 at 08:54:21AM +0100, Martin Husemann wrote:
On Wed, Mar 22, 2017 at 04:35:21PM +0900, Masanobu SAITOH wrote:
 So what should we do?

 A) modify pci_mapreg_map(). Stop setting BUS_SPACE_MAP_PREFETCHABLE
    by defalut when prefetchable bit is set. If a driver really know
    the whole area of the BAR is prefetchable, set BUS_SPACE_MAP_PREFETCHABLE
    in the 4th argument(busflags) of pci_mapreg_map(). pci_mapreg_map()
    check for both the 4th argument and the prefetchable bit, it sets
    BUS_SPACE_MAP_PREFETCHABLE only when both bits are set.
I prefer A.

This gets my vote too.

Same here.

I'm no expert in this area, but this option makes the most sense to me, too.

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