From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marex@denx.de>
Date: Sat, 10 Oct 2015 20:19:40 +0200
Subject: [U-Boot] [PATCH v3] nios2: convert dma_alloc_coherent to use
	memalign
In-Reply-To: <5618A312.1030306@wytron.com.tw>
References: <1444013823-11909-1-git-send-email-thomas@wytron.com.tw>
 <201510091649.28747.marex@denx.de> <5618A312.1030306@wytron.com.tw>
Message-ID: <201510102019.40613.marex@denx.de>
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On Saturday, October 10, 2015 at 07:33:06 AM, Thomas Chou wrote:
> Hi Marek,

Hi!

> On 10/09/2015 10:49 PM, Marek Vasut wrote:
> >> +	*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?
> 
> The *handle return a DMA address, and the function itself return a
> virtual address. Both of them should be set to NULL in case of failure.

So you depend on this property of memalign(), ok, I see. Thanks for clarifying!

> It might be wrong to keep DMA address looks alive but actually dead.

I don't quite understand this sentence, can you please rephrase it ?

Best regards,
Marek Vasut