From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755083Ab2HUBNv (ORCPT ); Mon, 20 Aug 2012 21:13:51 -0400 Received: from mail-vc0-f174.google.com ([209.85.220.174]:56148 "EHLO mail-vc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754320Ab2HUBNs (ORCPT ); Mon, 20 Aug 2012 21:13:48 -0400 MIME-Version: 1.0 In-Reply-To: <50324E84.6080407@ti.com> References: <1342466485-1050-1-git-send-email-omar.luna@linaro.org> <1342466485-1050-2-git-send-email-omar.luna@linaro.org> <50324E84.6080407@ti.com> Date: Mon, 20 Aug 2012 20:13:47 -0500 Message-ID: Subject: Re: [PATCH 1/3] ARM: OMAP: hwmod: partially un-reset hwmods might not be properly enabled From: Omar Ramirez Luna To: Benoit Cousson Cc: Paul Walmsley , Tony Lindgren , Russell King , Kevin Hilman , Ohad Ben-Cohen , Tomi Valkeinen , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Benoit, On 20 August 2012 09:49, Benoit Cousson wrote: > On 07/16/2012 09:21 PM, Omar Ramirez Luna wrote: >> Some IP blocks might not be using/controlling more than one >> reset line, this check loosens the restriction to fully use >> hwmod framework for those drivers. >> >> E.g.: ipu has reset lines: mmu_cache, cpu0 and cpu1. >> - cpu1 might not be used and hence (with previous check) >> won't be fully enabled by hwmod code. > > You mean that you might have some case where you need to enable the > mmu_cache and cpu0 and thus deassert only the mmu/cpu0 while keeping the > cpu1 under reset? > > So the any_hardreset is indeed not appropriate in that case. > > In fact, since the hardreset cannot be handled at all by the hwmod fmwk, > I'm even wondering if we should take care of checking the state at all. > But as Paul stated, if was done due to the lack of understanding about > the diver usage, so maybe things will become clearer once we will have > that code available. > > So I guess that checking for all the lines for the hardreset state is > anyway already a first step toward a good understanding of the reset > need for the remote processors. > > The patch looks fine to me considering that we do not have a lot of > information about the usage :-( > > Maybe you could add more information in the changelog to explain the way > you are going to use the reset API. I'll add an updated description with more information. Thanks for the comments, Omar From mboxrd@z Thu Jan 1 00:00:00 1970 From: omar.luna@linaro.org (Omar Ramirez Luna) Date: Mon, 20 Aug 2012 20:13:47 -0500 Subject: [PATCH 1/3] ARM: OMAP: hwmod: partially un-reset hwmods might not be properly enabled In-Reply-To: <50324E84.6080407@ti.com> References: <1342466485-1050-1-git-send-email-omar.luna@linaro.org> <1342466485-1050-2-git-send-email-omar.luna@linaro.org> <50324E84.6080407@ti.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Benoit, On 20 August 2012 09:49, Benoit Cousson wrote: > On 07/16/2012 09:21 PM, Omar Ramirez Luna wrote: >> Some IP blocks might not be using/controlling more than one >> reset line, this check loosens the restriction to fully use >> hwmod framework for those drivers. >> >> E.g.: ipu has reset lines: mmu_cache, cpu0 and cpu1. >> - cpu1 might not be used and hence (with previous check) >> won't be fully enabled by hwmod code. > > You mean that you might have some case where you need to enable the > mmu_cache and cpu0 and thus deassert only the mmu/cpu0 while keeping the > cpu1 under reset? > > So the any_hardreset is indeed not appropriate in that case. > > In fact, since the hardreset cannot be handled at all by the hwmod fmwk, > I'm even wondering if we should take care of checking the state at all. > But as Paul stated, if was done due to the lack of understanding about > the diver usage, so maybe things will become clearer once we will have > that code available. > > So I guess that checking for all the lines for the hardreset state is > anyway already a first step toward a good understanding of the reset > need for the remote processors. > > The patch looks fine to me considering that we do not have a lot of > information about the usage :-( > > Maybe you could add more information in the changelog to explain the way > you are going to use the reset API. I'll add an updated description with more information. Thanks for the comments, Omar