lkml.org 
[lkml]   [2014]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC] dma-mapping: Provide write-combine allocations
Hello,

On 2014-01-13 14:53, Thierry Reding wrote:
> Provide an implementation for dma_{alloc,free}_writecombine() when the
> architecture supports DMA attributes.
>
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
> arch/arm/include/asm/dma-mapping.h | 16 ----------------
> include/linux/dma-mapping.h | 16 ++++++++++++++++
> 2 files changed, 16 insertions(+), 16 deletions(-)
>
> diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
> index e701a4d9aa59..96b7634a7edc 100644
> --- a/arch/arm/include/asm/dma-mapping.h
> +++ b/arch/arm/include/asm/dma-mapping.h
> @@ -242,22 +242,6 @@ extern int arm_dma_mmap(struct device *dev, struct vm_area_struct *vma,
> void *cpu_addr, dma_addr_t dma_addr, size_t size,
> struct dma_attrs *attrs);
>
> -static inline void *dma_alloc_writecombine(struct device *dev, size_t size,
> - dma_addr_t *dma_handle, gfp_t flag)
> -{
> - DEFINE_DMA_ATTRS(attrs);
> - dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
> - return dma_alloc_attrs(dev, size, dma_handle, flag, &attrs);
> -}
> -
> -static inline void dma_free_writecombine(struct device *dev, size_t size,
> - void *cpu_addr, dma_addr_t dma_handle)
> -{
> - DEFINE_DMA_ATTRS(attrs);
> - dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
> - return dma_free_attrs(dev, size, cpu_addr, dma_handle, &attrs);
> -}
> -
> /*
> * This can be called during early boot to increase the size of the atomic
> * coherent DMA pool above the default value of 256KiB. It must be called
> diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
> index fd4aee29ad10..8475e02b4bd1 100644
> --- a/include/linux/dma-mapping.h
> +++ b/include/linux/dma-mapping.h
> @@ -249,6 +249,22 @@ struct dma_attrs;
> #define dma_unmap_sg_attrs(dev, sgl, nents, dir, attrs) \
> dma_unmap_sg(dev, sgl, nents, dir)
>
> +#else
> +static inline void *dma_alloc_writecombine(struct device *dev, size_t size,
> + dma_addr_t *dma_addr, gfp_t gfp)
> +{
> + DEFINE_DMA_ATTRS(attrs);
> + dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
> + return dma_alloc_attrs(dev, size, dma_addr, gfp, &attrs);
> +}
> +
> +static inline void dma_free_writecombine(struct device *dev, size_t size,
> + void *cpu_addr, dma_addr_t dma_addr)
> +{
> + DEFINE_DMA_ATTRS(attrs);
> + dma_set_attr(DMA_ATTR_WRITE_COMBINE, &attrs);
> + return dma_free_attrs(dev, size, cpu_addr, dma_addr, &attrs);
> +}
> #endif /* CONFIG_HAVE_DMA_ATTRS */
>
> #ifdef CONFIG_NEED_DMA_MAP_STATE

I would also add dma_mmap_writecombine() to the above functions.

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland



\
 
 \ /
  Last update: 2014-01-14 10:41    [W:0.033 / U:2.380 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site