From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marex@denx.de>
Date: Fri, 9 Oct 2015 16:49:28 +0200
Subject: [U-Boot] [PATCH v3] nios2: convert dma_alloc_coherent to use
	memalign
In-Reply-To: <1444390262-15804-1-git-send-email-thomas@wytron.com.tw>
References: <1444013823-11909-1-git-send-email-thomas@wytron.com.tw>
 <1444390262-15804-1-git-send-email-thomas@wytron.com.tw>
Message-ID: <201510091649.28747.marex@denx.de>
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To: u-boot@lists.denx.de

On Friday, October 09, 2015 at 01:31:02 PM, 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.
> 
>  arch/nios2/include/asm/dma-mapping.h | 23 ++++++++++-------------
>  1 file changed, 10 insertions(+), 13 deletions(-)
> 
> diff --git a/arch/nios2/include/asm/dma-mapping.h
> b/arch/nios2/include/asm/dma-mapping.h index 1350e3b..0618dc2 100644
> --- a/arch/nios2/include/asm/dma-mapping.h
> +++ b/arch/nios2/include/asm/dma-mapping.h
> @@ -1,23 +1,20 @@
>  #ifndef __ASM_NIOS2_DMA_MAPPING_H
>  #define __ASM_NIOS2_DMA_MAPPING_H
> 
> -/* dma_alloc_coherent() return cache-line aligned allocation which is
> mapped +#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)memalign(ARCH_DMA_MINALIGN, len);

This still modifies the handle in both cases (failure and success).
We really want to modify external variables in case of failure, no?

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

Best regards,
Marek Vasut