Re: [RFC] switch m68k to use the generic remapping DMA allocator

[Geert Uytterhoeven]

Hi Christoph,

On Fri, Jun 14, 2019 at 12:21 PM Christoph Hellwig <hch@xxxxxx> wrote:
> can you take a look at the (untested) patches below?  They convert m68k
> to use the generic remapping DMA allocator, which is also used by
> arm64 and csky.

When building for Sun-3:

kernel/dma/remap.o: In function `arch_dma_alloc':
remap.c:(.text+0x316): undefined reference to `__dma_direct_alloc_pages'
remap.c:(.text+0x32a): undefined reference to `arch_dma_prep_coherent'
remap.c:(.text+0x34e): undefined reference to `arch_dma_mmap_pgprot'
remap.c:(.text+0x378): undefined reference to `__dma_direct_free_pages'
remap.c:(.text+0x3f4): undefined reference to `arch_dma_prep_coherent'
remap.c:(.text+0x40a): undefined reference to `__dma_direct_alloc_pages'
kernel/dma/remap.o: In function `arch_dma_free':
remap.c:(.text+0x446): undefined reference to `__dma_direct_free_pages'
remap.c:(.text+0x4a8): undefined reference to `__dma_direct_free_pages'
kernel/dma/remap.o: In function `dma_atomic_pool_init':
remap.c:(.init.text+0x66): undefined reference to `arch_dma_prep_coherent'

Doing

-       select DMA_DIRECT_REMAP if MMU && !COLDFIRE
+       select DMA_DIRECT_REMAP if MMU && !COLDFIRE && !SUN3

in arch/m68k/Kconfig fixes the build.

Alternatively, you could use:

-       select DMA_DIRECT_REMAP if MMU && !COLDFIRE
+       select DMA_DIRECT_REMAP if HAS_DMA && MMU && !COLDFIRE

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds