Hi, On Fri, Jun 14, 2019 at 09:24:16AM +0200, Mathieu Malaterre wrote: > On Thu, Jun 13, 2019 at 10:27 AM Christoph Hellwig <h...@lst.de> wrote: > > With the strict dma mask checking introduced with the switch to > > the generic DMA direct code common wifi chips on 32-bit powerbooks > > stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds > > to allow them to reliably allocate dma coherent memory. > > > > Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported") > > Reported-by: Aaro Koskinen <aaro.koski...@iki.fi> > > Signed-off-by: Christoph Hellwig <h...@lst.de> > > --- > > arch/powerpc/include/asm/page.h | 7 +++++++ > > arch/powerpc/mm/mem.c | 3 ++- > > arch/powerpc/platforms/powermac/Kconfig | 1 + > > 3 files changed, 10 insertions(+), 1 deletion(-) > > > > diff --git a/arch/powerpc/include/asm/page.h > > b/arch/powerpc/include/asm/page.h > > index b8286a2013b4..0d52f57fca04 100644 > > --- a/arch/powerpc/include/asm/page.h > > +++ b/arch/powerpc/include/asm/page.h > > @@ -319,6 +319,13 @@ struct vm_area_struct; > > #endif /* __ASSEMBLY__ */ > > #include <asm/slice.h> > > > > +/* > > + * Allow 30-bit DMA for very limited Broadcom wifi chips on many > > powerbooks. > > nit: would it be possible to mention explicit reference to b43-legacy. > Using b43 on my macmini g4 never showed those symptoms (using > 5.2.0-rc2+)
According to Wikipedia Mac mini G4 is limited to 1 GB RAM, so that's why you don't see the issue. A.