From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gediminas Simanskis Subject: Re: Linux board with 10 CANs Date: Wed, 20 May 2015 14:35:06 +0300 Message-ID: <555C716A.3090509@8devices.com> References: <5555A6A3.7090206@orange.fr> <5555FAAB.4090306@universalnet.at> <5559ABE6.5030206@orange.fr> <5559E994.4000103@universalnet.at> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-wi0-f171.google.com ([209.85.212.171]:34002 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750734AbbETLfL (ORCPT ); Wed, 20 May 2015 07:35:11 -0400 Received: by wicmc15 with SMTP id mc15so146734389wic.1 for ; Wed, 20 May 2015 04:35:10 -0700 (PDT) In-Reply-To: <5559E994.4000103@universalnet.at> Sender: linux-can-owner@vger.kernel.org List-ID: To: Bernd Krumboeck Cc: =?UTF-8?B?RnJhbsOnb2lzIEJlYXVsaWVy?= , linux-can@vger.kernel.org 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 Fran=C3=A7ois Beaulier: >> Le 15/05/2015 15:54, Bernd Krumboeck a =C3=A9crit : >>> Hi! >>> >>> >>> I don't know much about this things, but what do you think about=20 >>> following: >>> >>> Use two 4 port usb hub (MICROCHIP USB4624I-1080HN) with 8 x=20 >>> STM32F072 or STR750FV2. >>> >>> You can flash the MCUs under linux with dfu-util=20 >>> (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=20 >> firmware existed. >> I looked in the gcc-test repository, and apart from ST files the=20 >> license is not specified. >> Can you tell us more about license ? >> >> Francois >> >> >>> >>> >>> Am 2015-05-15 um 09:56 schrieb Fran=C3=A7ois Beaulier: >>>> Hi, >>>> >>>> I'm starting the design of a CPU board, based on a computer on=20 >>>> 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.=20 >>>> (The SOC have 2 CANs so i need 8 more) >>>> The board will run with Linux and of course i want a socketcan=20 >>>> interface for each bus ! >>>> CAN bitrate needed is quite low (50kbps) and latency is not=20 >>>> critical but bus load may reach 100% sometimes. >>>> As far as possible i want to avoid driver development, or just=20 >>>> doing slight modifications on an existing driver. >>>> I don't want to use MCP2515, i had trouble with it on a previous=20 >>>> design because of the lack of buffer in the chip. >>>> I can't imagine putting 8 MCP2515 and not missing any frame, but=20 >>>> may be i'm wrong ? >>>> >>>> Here are the options i have considered, they involve using externa= l=20 >>>> MCUs to provide enough CAN interfaces : >>>> >>>> - MCUs with SLCAN : SLCAN have the advantage of simplicity and it=20 >>>> should offer enough performance at low data rate. Problem is that=20 >>>> it would require 8 UARTS. I could modify SLCAN driver to allow=20 >>>> multiple CAN channels on the same UART, and so use MCUs with=20 >>>> multiple CANs, does it sounds reasonable ? >>>> >>>> - MCUs with SPI 1 : adapt MCP2515 driver in a way to make the SPI=20 >>>> protocol manageable on the MCU side (SPI slave). The MCU will be=20 >>>> able to provide the buffer for CAN frames that the MCP does not=20 >>>> have. This option is just a way of trying to go fast, it is not=20 >>>> very elegant, and have the limitation of one CAN channel per SPI=20 >>>> connection / driver instance. >>>> >>>> - MCUs with SPI 2 : use the Stefano Babic SPI driver posted on thi= s=20 >>>> list. This is probably the best choice for a long term and more=20 >>>> generic solution. But i'm afraid it may require too much work to=20 >>>> complete. What is the status of this driver right now ? Does anyon= e=20 >>>> have an idea of the remaining work to do to make it ready for=20 >>>> mainline ? Stefano are you available to spend more time on it ? I'= m=20 >>>> also wondering whether multiple instances of the driver can run=20 >>>> concurently if i put more than one MCU ? >>>> >>>> Concerning the MCU software i could release it as an open-source=20 >>>> project, anyone interested in participating ? >>>> I'm very familiar with STM32 MCUs so i will probably use an=20 >>>> STM32F072 (low cost cortex M0 with one CAN). >>>> >>>> Any idea or advice is welcome, thank you for reading this much too= =20 >>>> long post. >>>> >>>> Regards >>>> >>>> Francois Beaulier >>>> www.ingelibre.fr >>>> --=20 >>>> To unsubscribe from this list: send the line "unsubscribe=20 >>>> linux-can" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> >> --=20 >> 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 >