From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from db8outboundpool.messaging.microsoft.com (mail-db8lp0188.outbound.messaging.microsoft.com [213.199.154.188]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client CN "mail.global.frontbridge.com", Issuer "Microsoft Secure Server Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 35C622C00C1 for ; Tue, 30 Apr 2013 06:29:55 +1000 (EST) Date: Mon, 29 Apr 2013 15:29:44 -0500 From: Scott Wood Subject: Re: [PATCH 2/2 V7] powerpc/85xx: Add machine check handler to fix PCIe erratum on mpc85xx To: Jia Hongtao-B38951 References: <1366684776-10946-1-git-send-email-hongtao.jia@freescale.com> <1366684776-10946-2-git-send-email-hongtao.jia@freescale.com> <1366909096.30341.3@snotra> <412C8208B4A0464FA894C5F0C278CD5D01C4C76D@039-SN1MPN1-002.039d.mgd.msft.net> In-Reply-To: <412C8208B4A0464FA894C5F0C278CD5D01C4C76D@039-SN1MPN1-002.039d.mgd.msft.net> (from B38951@freescale.com on Fri Apr 26 21:26:26 2013) Message-ID: <1367267384.32182.14@snotra> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; delsp=Yes; format=Flowed Cc: Wood Scott-B07421 , "linuxppc-dev@lists.ozlabs.org" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 04/26/2013 09:26:26 PM, Jia Hongtao-B38951 wrote: > > -----Original Message----- > > From: Wood Scott-B07421 > > Sent: Friday, April 26, 2013 12:58 AM > > To: Segher Boessenkool > > Cc: Jia Hongtao-B38951; linuxppc-dev@lists.ozlabs.org; > > galak@kernel.crashing.org; Wood Scott-B07421 > > Subject: Re: [PATCH 2/2 V7] powerpc/85xx: Add machine check handler =20 > to > > fix PCIe erratum on mpc85xx > > > > On 04/25/2013 10:31:51 AM, Segher Boessenkool wrote: > > >> * Remove A variant of load instruction emulation > > > > > > Why is this? You handle all other simple load insns, there is =20 > nothing > > > special about LHA. (I reviewed the V4 email thread, no reason =20 > for the > > > chance is given there). > > > > The LHA implementation in V5 was incorrect (didn't sign-extend). > > > > -Scott >=20 > In former email you doubt whether we need A variant or not. > Any particular reason for that? > If not should I emulate all the A ARX AU AUX and AX variant? I was just noting that the variants you left out from the earlier =20 revisions (e.g. BRX) were much more likely to be used for I/O than some =20 of the ones you included (e.g. "A"). Implementing all the normal =20 load/store instructions would be better, if they're done correctly. -Scott=