Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754390Ab1FPGMy (ORCPT ); Thu, 16 Jun 2011 02:12:54 -0400 Received: from sr-smtp.usish.com ([210.5.144.203]:51871 "EHLO sr-smtp.usish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751546Ab1FPGMv (ORCPT ); Thu, 16 Jun 2011 02:12:51 -0400 From: "Jack Wang" To: "'Xiangliang Yu'" , "'James Bottomley'" Cc: , , , , , , "'Jacky Feng'" References: <1308064628-11826-1-git-send-email-yxlraid@gmail.com> <1308065367.2401.24.camel@mulgrave> <1308117450.2329.31.camel@mulgrave> <637AF86F1A314F15B816411A580575F0@usish.com.cn> <51A55E816E3847EF97FE4E849A572717@usish.com.cn> Subject: RE: [PATCH] [SCSI] LIBSAS: fix libsas link error issue Date: Thu, 16 Jun 2011 14:12:19 +0800 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 11 Thread-Index: AcwrIR/qdpMMo2uOTdi6EtZ/SnmPkgAAZ5KAACgYoPAAAOfC4AABCYdAAABOEGAAA867gAAA6NjQAAMaV6A= In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6090 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1874 Lines: 46 > >> > [Jack Wang] > >> >It's the same, sas_ex_get_linkrate use DISCOVER response as linkrate. > >> But the function have problem, actually, the error statement is: > >> child->linkrate = min(parent_phy->linkrate, child->max_linkrate); > >> its mean like this: > >> child->linkrate = min(child_phy->linkrate, > >> max(parent->max_linkrate,child_phy->linkrate)); > >> and if parent->max_linkrate(3Gbps) is less than > child_phy->linkrate(6Gbps), > >> the statement will be change this: > >> child->linkrate = child_phy->linkrate, forget the parent linkrate. > >[Jack Wang] > >I don't think the statement below is error: > >child->linkrate = min(parent_phy->linkrate, child->max_linkrate); > >parent_phy->linkrate is came from sas_set_ex_phy which will set the linkrate > >to negotiated logical linkrate. For your eg: you topo like this: > >hba(3G)---expander1(6G)---expander2(6G): > > Yes, you can test like this. > >Then expander1's linkrate will set to 3G, and expander2's linkrate will set > >to 6G, that is correct. > yes > > But the connection rate will be 3G from hba to > >expander2. > How to configure the connection rate? > Now, MVSAS driver get 6G from sas_ex_get_linkrate function, and set linkrate > of OPEN address frame to the value. right? > > -- [Jack Wang] Connection rate is auto, link layer will insert deletable primitives to do rate matching (sas2r15 7.14). Yes, you should set the linkrate to that value . > To unsubscribe from this list: send the line "unsubscribe linux-scsi" 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-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/