From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp02.in.ibm.com ([122.248.162.2]:38759 "EHLO e28smtp02.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751709AbaH2EV3 (ORCPT ); Fri, 29 Aug 2014 00:21:29 -0400 Received: from /spool/local by e28smtp02.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 29 Aug 2014 09:51:27 +0530 Date: Fri, 29 Aug 2014 12:21:21 +0800 From: Wei Yang To: Bob Biloxi Cc: "linux-rdma@vger.kernel.org" , "linux-pci@vger.kernel.org" Subject: Re: mlx4 query in sriov mode Message-ID: <20140829042121.GA31486@richard> Reply-To: Wei Yang References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-pci-owner@vger.kernel.org List-ID: On Thu, Aug 28, 2014 at 10:58:50PM +0530, Bob Biloxi wrote: >Hi All, > > >I really appreciate this wonderful community which has immensely >helped me broaden my knowledge and understanding. > > >I was going through the mlx4 sriov code, trying to understand the >communication between the VF driver and the PF driver. > >I was having a few queries..hoping to get a better understanding. > > >As I understand, the commands are communicated between VF and PF >through a mechanism called communication channel. VF writes to >specific address in its BAR space, PF gets an event and then proceeds >ahead to read the command from its BAR space and then complete the >execution of it.. > > >Now, my query is, lets say the VF driver is not yet present and only >the PF driver is there... > >In this case, can we simulate a VF command write and get notified >through an event? > Hi, I am not that familiar with mlx4 driver. As you mentioned in previous, VF communicate with PF by writing some word in BAR and PF gets it. If this is true, I believe it would works. >For eg. we write to some offset in the PF BAR space itself upon >completion of which, an event is generated because of the write? kind >of like loopback mechanism. > > >I searched through the code but couldn't find anywhere. > >Can anyone please help me understand if this is possible? And if there >is any location in the code where i can find this? Where you fund the communication between PF and VF is by writing its BAR? > >Thanks a lot in advance!! > > >Best Regards, >Bob >-- >To unsubscribe from this list: send the line "unsubscribe linux-pci" in >the body of a message to majordomo@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html -- Richard Yang Help you, Help me