From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bernd Krumboeck Subject: Re: Linux board with 10 CANs Date: Mon, 18 May 2015 15:31:00 +0200 Message-ID: <5559E994.4000103@universalnet.at> References: <5555A6A3.7090206@orange.fr> <5555FAAB.4090306@universalnet.at> <5559ABE6.5030206@orange.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from smtp.xy24.at ([85.126.109.136]:59075 "EHLO renate.xy24.at" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753791AbbERNbU (ORCPT ); Mon, 18 May 2015 09:31:20 -0400 In-Reply-To: <5559ABE6.5030206@orange.fr> Sender: linux-can-owner@vger.kernel.org List-ID: To: Gediminas Simanskis Cc: =?UTF-8?B?RnJhbsOnb2lzIEJlYXVsaWVy?= , linux-can@vger.kernel.org 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 fol= lowing: >> >> Use two 4 port usb hub (MICROCHIP USB4624I-1080HN) with 8 x STM32F07= 2 or STR750FV2. >> >> You can flash the MCUs under linux with dfu-util (http://dfu-util.so= urceforge.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 firmw= are existed. > I looked in the gcc-test repository, and apart from ST files the lice= nse 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 modu= le 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. (Th= e SOC have 2 CANs so i need 8 more) >>> The board will run with Linux and of course i want a socketcan inte= rface for each bus ! >>> CAN bitrate needed is quite low (50kbps) and latency is not critica= l but bus load may reach 100% sometimes. >>> As far as possible i want to avoid driver development, or just doin= g slight modifications on an existing driver. >>> I don't want to use MCP2515, i had trouble with it on a previous de= sign because of the lack of buffer in the chip. >>> I can't imagine putting 8 MCP2515 and not missing any frame, but ma= y 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 s= hould offer enough performance at low data rate. Problem is that it wou= ld require 8 UARTS. I could modify SLCAN driver to allow multiple CAN c= hannels on the same UART, and so use MCUs with multiple CANs, does it s= ounds reasonable ? >>> >>> - MCUs with SPI 1 : adapt MCP2515 driver in a way to make the SPI p= rotocol 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 opt= ion is just a way of trying to go fast, it is not very elegant, and hav= e the limitation of one CAN channel per SPI connection / driver instanc= e. >>> >>> - 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 generi= c solution. But i'm afraid it may require too much work to complete. Wh= at 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 y= ou available to spend more time on it ? I'm also wondering whether mult= iple 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 pr= oject, anyone interested in participating ? >>> I'm very familiar with STM32 MCUs so i will probably use an STM32F0= 72 (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