Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751158Ab3IXIAJ (ORCPT ); Tue, 24 Sep 2013 04:00:09 -0400 Received: from pegase1.c-s.fr ([93.17.236.30]:31976 "EHLO mailhub1.si.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750754Ab3IXIAI (ORCPT ); Tue, 24 Sep 2013 04:00:08 -0400 Message-ID: <52414682.3010608@c-s.fr> Date: Tue, 24 Sep 2013 10:00:02 +0200 From: leroy christophe User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Scott Wood CC: Benjamin Herrenschmidt , Paul Mackerras , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Joakim Tjernlund Subject: Re: [PATCH v2] powerpc 8xx: Fixing issue with CONFIG_PIN_TLB References: <201309121825.r8CIPrkI005690@localhost.localdomain> <1379011469.2536.45.camel@snotra.buserror.net> <52329CDF.9020103@c-s.fr> <1379365336.2536.166.camel@snotra.buserror.net> <5238860F.4030405@c-s.fr> <1379712141.16231.36.camel@aoeu.buserror.net> In-Reply-To: <1379712141.16231.36.camel@aoeu.buserror.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1273 Lines: 30 Le 20/09/2013 23:22, Scott Wood a écrit : >>> The hardware wants to decrement; why fight it? >> >I see your point. >> >However it is not clear in the documentation if the decrement is done >> >really after the update, or at xTLB interrupt. So I propose to still set >> >the CTR ourself as described in the reference Manual and not assume that >> >the HW decrements it. > It says "every update" -- do you have any reason to believe that's > wrong? It could be tested... > > Ok. I just test it, and I observe the following: As we have set the RSV4x bit, the CPU sets Mx_CTR to a value below 0x1c after each update: * After writing entry 0x1c, Mx_CTR has value 0x1b * After writing entry 0x1d, Mx_CTR has value 0x18 * After writing entry 0x1e, Mx_CTR has value 0x19 * After writing entry 0x1f, Mx_CTR has value 0x1a Indeed the first version of my patch was complete, only the description was not fully correct. So, in order to minimise code churn, I will re-submit my initial patch with a modified description. Christophe -- 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/