Messages in this thread | | | Date | Fri, 11 Aug 2017 19:56:41 +0200 | From | Christoph Hellwig <> | Subject | Re: [PATCH 1/2] of: Fix DMA mask generation |
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On Fri, Aug 11, 2017 at 05:29:56PM +0100, Robin Murphy wrote: > Historically, DMA masks have suffered some ambiguity between whether > they represent the range of physical memory a device can access, or the > address bits a device is capable of driving, particularly since on many > platforms the two are equivalent. Whilst there are some stragglers left > (dma_max_pfn(), I'm looking at you...), the majority of DMA code has > been cleaned up to follow the latter definition, not least since it is > the only one which makes sense once IOMMUs are involved.
I think it always was supposed to be the latter, but that doesn't mean that everyone got the message :)
> Either of these patches alone should be sufficient to un-break RPi3, > and they apply independently, so I'm quite happy for one to go in as a > fix now and the other to wait for 4.14.
This one is something I'm comfortable feeding to Linus for 4.13 if I get a few ACKs from people familar with the OF code and intended meaning of the ranges in the device tree.
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