Re: [PATCH/RFC 0/6] Allow compile-testing NO_DMA

2018-02-06 Thread Arnd Bergmann
On Tue, Feb 6, 2018 at 2:05 PM, Robin Murphy wrote: > > It looks like we have only one real arch (score) without IOMEM, and two > (s390 and tile) where it is possible to configure out, so it does seem like > a reasonable feature to assume. Maybe we could have something like > asm-generic/no-io.h t

Re: [PATCH/RFC 0/6] Allow compile-testing NO_DMA

2018-02-06 Thread Arnd Bergmann
On Tue, Feb 6, 2018 at 11:14 AM, Geert Uytterhoeven wrote: > Hi all, > > If NO_DMA=y, get_dma_ops() returns a reference to the non-existing > symbol bad_dma_ops, thus causing a link failure if it is ever used. > > The intention of this is twofold: > 1. To catch users of the DMA API on sy

Re: [PATCH/RFC 0/6] Allow compile-testing NO_DMA

2018-02-06 Thread Robin Murphy
On 06/02/18 10:14, Geert Uytterhoeven wrote: Hi all, If NO_DMA=y, get_dma_ops() returns a reference to the non-existing symbol bad_dma_ops, thus causing a link failure if it is ever used. The intention of this is twofold: 1. To catch users of the DMA API on systems that do no support

Re: [PATCH/RFC 0/6] Allow compile-testing NO_DMA

2018-02-06 Thread Mark Brown
On Tue, Feb 06, 2018 at 11:14:46AM +0100, Geert Uytterhoeven wrote: > The intention of this is twofold: > 1. To catch users of the DMA API on systems that do no support the DMA > mapping API, > 2. To avoid building drivers that cannot work on such systems anyway. > > However, the disadva

[PATCH/RFC 0/6] Allow compile-testing NO_DMA

2018-02-06 Thread Geert Uytterhoeven
Hi all, If NO_DMA=y, get_dma_ops() returns a reference to the non-existing symbol bad_dma_ops, thus causing a link failure if it is ever used. The intention of this is twofold: 1. To catch users of the DMA API on systems that do no support the DMA mapping API, 2. To avoid buildin