Subject: [PATCH] arm: dma-mapping: fix compilation error when CONFIG_MMU is not present

From: [email-masked] (Laura Abbott)
Date: Mon, 20 Oct 2014 17:05:25 -0700

On 10/20/2014 6:50 AM, Stefan Hengelein wrote:
> Well,
>
> arch/arm/mm/dma-mapping.c: In function ?__atomic_get_pages?:
> arch/arm/mm/dma-mapping.c:1265:31: error: ?atomic_pool? undeclared
> (first use in this function)
>
> arch/arm/mm/dma-mapping.c: In function ?__iommu_get_pages?:
> arch/arm/mm/dma-mapping.c:1275:2: error: implicit declaration of
> function ?__in_atomic_pool? [-Werror=implicit-function-declaration]
>
>
> others:
> arch/arm/mm/dma-mapping.c: In function ?__iommu_alloc_remap?:
> arch/arm/mm/dma-mapping.c:1200:4: error: ?VM_ARM_DMA_CONSISTENT?
> undeclared (first use in this function)
> arch/arm/mm/dma-mapping.c:1200:4: note: each undeclared identifier is
> reported only once for each function it appears in
>
> arch/arm/mm/dma-mapping.c: In function ?__iommu_get_pages?:
> arch/arm/mm/dma-mapping.c:1282:29: error: ?VM_ARM_DMA_CONSISTENT?
> undeclared (first use in this function)
> arch/arm/mm/dma-mapping.c: In function ?arm_iommu_free_attrs?:
> arch/arm/mm/dma-mapping.c:1411:4: error: ?VM_ARM_DMA_CONSISTENT?
> undeclared (first use in this function)
>
>
> i've attached a configuration where it happens.
> when you place the configuration in your tree and compile the file,
> the errors should show up.
>
> However, within the configuration CONFIG_ARM_DMA_USE_IOMMU is defined
> and CONFIG_MMU is not. AFAIUI, if both should be enabled together, it
> should be mapped in Kconfig somewhere, right?
>
> Best Regards,
> Stefan
>

There isn't a nice way to fixup the dma consistent flags so I would
say this option should just depend on MMU.

Thanks,
Laura

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