Re: Linux board with 10 CANs

[Bernd Krumboeck <krumboeck@universalnet.at>]

Thank you for the fast response.
I'll update the notes on github (asap).


regards,
Bernd


Am 2015-05-20 um 13:35 schrieb Gediminas Simanskis:
> Hi,
> GPL2
> Gediminas
>
> On 2015-05-18 16:31, Bernd Krumboeck wrote:
>> Hi Gediminas!
>>
>>
>> Can you tell us the license of the source code from usb2can firmware?
>>
>>
>> regards,
>> Bernd
>>
>>
>> Am 2015-05-18 um 11:07 schrieb François Beaulier:
>>> Le 15/05/2015 15:54, Bernd Krumboeck a écrit :
>>>> Hi!
>>>>
>>>>
>>>> I don't know much about this things, but what do you think about following:
>>>>
>>>> Use two 4 port usb hub (MICROCHIP USB4624I-1080HN) with 8 x STM32F072 or STR750FV2.
>>>>
>>>> You can flash the MCUs under linux with dfu-util (http://dfu-util.sourceforge.net/).
>>>>
>>>> A firmware for STR750FV2 is available here (please check license):
>>>> https://github.com/krumboeck/usb2can_firmware
>>>>
>>>> I don't know if it works, but there is also a gcc version available:
>>>> https://github.com/krumboeck/usb2can_firmware/tree/gcc-test
>>>>
>>>>
>>>> If you use this firmware or at least the same procotol, then the
>>>> hardware will be compatible with usb_8dev can driver.
>>>>
>>>>
>>>> regards,
>>>> Bernd
>>>>
>>>>
>>>
>>> Hi Bernd,
>>>
>>> Thank you for pointed out this USB solution. I didn't know such firmware existed.
>>> I looked in the gcc-test repository, and apart from ST files the license is not specified.
>>> Can you tell us more about license ?
>>>
>>> Francois
>>>
>>>
>>>>
>>>>
>>>> Am 2015-05-15 um 09:56 schrieb François Beaulier:
>>>>> Hi,
>>>>>
>>>>> I'm starting the design of a CPU board, based on a computer on module with a very common SOC like i.mx6 or am335x.
>>>>> I need to fit my board with at least 10 CAN ports, may be more. (The SOC have 2 CANs so i need 8 more)
>>>>> The board will run with Linux and of course i want a socketcan interface for each bus !
>>>>> CAN bitrate needed is quite low (50kbps) and latency is not critical but bus load may reach 100% sometimes.
>>>>> As far as possible i want to avoid driver development, or just doing slight modifications on an existing driver.
>>>>> I don't want to use MCP2515, i had trouble with it on a previous design because of the lack of buffer in the chip.
>>>>> I can't imagine putting 8 MCP2515 and not missing any frame, but may be i'm wrong ?
>>>>>
>>>>> Here are the options i have considered, they involve using external MCUs to provide enough CAN interfaces :
>>>>>
>>>>> - MCUs with SLCAN : SLCAN have the advantage of simplicity and it should offer enough performance at low data rate. Problem is that it would require 8 UARTS. I could modify SLCAN driver to allow multiple CAN channels on the same UART, and so use MCUs with multiple CANs, does it sounds reasonable ?
>>>>>
>>>>> - MCUs with SPI 1 : adapt MCP2515 driver in a way to make the SPI protocol manageable on the MCU side (SPI slave). The MCU will be able to provide the buffer for CAN frames that the MCP does not have. This option is just a way of trying to go fast, it is not very elegant, and have the limitation of one CAN channel per SPI connection / driver instance.
>>>>>
>>>>> - MCUs with SPI 2 : use the Stefano Babic SPI driver posted on this list. This is probably the best choice for a long term and more generic solution. But i'm afraid it may require too much work to complete. What is the status of this driver right now ? Does anyone have an idea of the remaining work to do to make it ready for mainline ? Stefano are you available to spend more time on it ? I'm also wondering whether multiple instances of the driver can run concurently if i put more than one MCU ?
>>>>>
>>>>> Concerning the MCU software i could release it as an open-source project, anyone interested in participating ?
>>>>> I'm very familiar with STM32 MCUs so i will probably use an STM32F072 (low cost cortex M0 with one CAN).
>>>>>
>>>>> Any idea or advice is welcome, thank you for reading this much too long post.
>>>>>
>>>>> Regards
>>>>>
>>>>> Francois Beaulier
>>>>> www.ingelibre.fr
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-can" in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-can" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-can" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html