[U-Boot] [PATCH v4] nios2: convert dma_alloc_coherent to use malloc_cache_aligned

[Marek Vasut <marex@denx.de>]

On Monday, October 12, 2015 at 07:29:43 AM, Thomas Chou wrote:
> Convert dma_alloc_coherent to use memalign.
> 
> Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
> ---
> v2
>   use memalign.
> v3
>   check memalign() return for out of memory.
> v4
>   use malloc_cache_aligned().
> 
>  arch/nios2/include/asm/dma-mapping.h | 24 +++++++++++-------------
>  1 file changed, 11 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/nios2/include/asm/dma-mapping.h
> b/arch/nios2/include/asm/dma-mapping.h index 1350e3b..bfaf662 100644
> --- a/arch/nios2/include/asm/dma-mapping.h
> +++ b/arch/nios2/include/asm/dma-mapping.h
> @@ -1,23 +1,21 @@
>  #ifndef __ASM_NIOS2_DMA_MAPPING_H
>  #define __ASM_NIOS2_DMA_MAPPING_H
> 
> -/* dma_alloc_coherent() return cache-line aligned allocation which is
> mapped +#include <memalign.h>
> +#include <asm/io.h>
> +
> +/*
> + * dma_alloc_coherent() return cache-line aligned allocation which is
> mapped * to uncached io region.
> - *
> - * IO_REGION_BASE should be defined in board config header file
> - *   0x80000000 for nommu, 0xe0000000 for mmu
>   */
> -
>  static inline void *dma_alloc_coherent(size_t len, unsigned long *handle)
>  {
> -	void *addr = malloc(len + CONFIG_SYS_DCACHELINE_SIZE);
> -	if (!addr)
> -		return 0;
> -	flush_dcache((unsigned long)addr, len + CONFIG_SYS_DCACHELINE_SIZE);
> -	*handle = ((unsigned long)addr +
> -		   (CONFIG_SYS_DCACHELINE_SIZE - 1)) &
> -		~(CONFIG_SYS_DCACHELINE_SIZE - 1) & ~(IO_REGION_BASE);
> -	return (void *)(*handle | IO_REGION_BASE);
> +	*handle = (unsigned long)malloc_cache_aligned(len);
> +	if (!*handle)
> +		return NULL;
> +	flush_dcache_range(*handle, *handle + len);

Wouldn't invalidate_dcache_range() be enough here ? You don't care about the
data in the newly allocated area at this point I guess -- either you fill them
in and then flush, for DMA from CPU to device OR you receive data from device
to CPU and then you invalidate this buffer again.

> +	return ioremap(*handle, len);
>  }
> 
>  #endif /* __ASM_NIOS2_DMA_MAPPING_H */

Best regards,
Marek Vasut