Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

From: Larry Finger
Date: Thu Jun 13 2019 - 14:56:29 EST


On 6/13/19 3:24 AM, Christoph Hellwig 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.koskinen@xxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>

As expected, it works. The patch needs
Cc: Stable <stable*vger.kernel.org> # v5.1+

Tested-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Acked-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

Thanks for the help, and the patience with my debugging problems with u64 variables.

Larry