From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Wed, 22 Jan 2014 15:04:14 +0100
From: Alexandre COFFIGNAL <acoffignal@geral.com>
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Subject: Re: [Xenomai] imx28 rtcan flexcan system freezes
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Le 22/01/2014 14:30, Gilles Chanteperdrix a =E9crit :
> On 01/22/2014 02:27 PM, Alexandre COFFIGNAL wrote:
>>
>> Le 22/01/2014 13:00, Gilles Chanteperdrix a =E9crit :
>>> On 01/22/2014 12:36 PM, Alexandre COFFIGNAL wrote:
>>>>>> +        cf->data[3]=3D((data0 >> 0)  & 0xFF) ;
>>>>>> +        cf->data[2]=3D((data0 >> 8)  & 0xFF) ;
>>>>>> +        cf->data[1]=3D((data0 >> 16)  & 0xFF) ;
>>>>>> +        cf->data[0]=3D((data0 >> 24)  & 0xFF) ;
>>>>>> +        cf->data[7]=3D((data1 >> 0)  & 0xFF) ;
>>>>>> +        cf->data[6]=3D((data1 >> 8)  & 0xFF) ;
>>>>>> +        cf->data[5]=3D((data1 >> 16)  & 0xFF) ;
>>>>>> +        cf->data[4]=3D((data1 >> 24)  & 0xFF) ;
>>>>>>
>>>>>> rtcan flexcan works perfectly.
>>>>>> is  anyone know what is the problem with first instructions ?
>>>>> Probably mb->data does not have the right alignment. Could you not
>>>>> arrange to get it properly aligned? Failing that, you should use
>>>>> put_unaligned instead of open coding it.
>>>>>
>>>>>
>>>> here structures used in flexcan driver, it seem to be aligned
>>>
>>> I am talking about the alignment of cf->data, since obviously, that is
>>> the one which is causing problems.
>>>
>>>
>> Thank a lot, put_unaligned fix this issue if you want, i can send a path
>>
>
> The other solution (getting cf->data to be properly aligned) would be=20
> more efficient, why is not it possible to get cf->data properly aligned?
>
I think, i can't get cf->data to be properly aligned because "cf" is=20
receive internal frame representation within the ring buffer
of a struct rtcan_socket and struct rtcan_rb_frame is a generic=20
structure used in all rtcan drivers .