[3/3] powerpc/dma: Remove ZONE_DMA completely

[Michael Ellerman]

On Fri, 2015-20-02 at 08:35:44 UTC, Benjamin Herrenschmidt wrote:
> We don't initialize it, we don't use it, remove it.
> 
> We can bring it back if we ever wish to have support for devices
> who have smaller than 32-bit DMA limitations but I don't think
> we care much anymore.
> 
> Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> ---
>  arch/powerpc/Kconfig      |    2 +-
>  arch/powerpc/kernel/dma.c |   10 +---------
>  2 files changed, 2 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> index 22b0940..4efbfba 100644
> --- a/arch/powerpc/Kconfig
> +++ b/arch/powerpc/Kconfig
> @@ -712,7 +712,7 @@ config ISA
>  
>  config ZONE_DMA
>  	bool
> -	default y
> +	default n
>  
>  config NEED_DMA_MAP_STATE
>  	def_bool (PPC64 || NOT_COHERENT_CACHE)
> diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
> index e24e0ae..6306d4e 100644
> --- a/arch/powerpc/kernel/dma.c
> +++ b/arch/powerpc/kernel/dma.c
> @@ -63,16 +63,8 @@ void *dma_direct_alloc_coherent(struct device *dev, size_t size,
>  		return NULL;
>  	}
>  
> -	switch (zone) {
> -	case ZONE_DMA:
> -		flag |= GFP_DMA;
> -		break;
> -#ifdef CONFIG_ZONE_DMA32
> -	case ZONE_DMA32:
> +	if (zone == ZONE_DMA32)
>  		flag |= GFP_DMA32;
> -		break;
> -#endif
> -	};

You still need the ifdef, else eg. ppc6xx_defconfig:

  arch/powerpc/kernel/dma.c:66:14: error: 'ZONE_DMA32' undeclared (first use in this function)

cheers