From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from top.free-electrons.com ([176.31.233.9]:49347 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752401AbaAVW4j (ORCPT ); Wed, 22 Jan 2014 17:56:39 -0500 Date: Wed, 22 Jan 2014 19:56:55 -0300 From: Ezequiel Garcia To: Jason Gunthorpe Cc: Sebastian Hesselbarth , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, Lior Amsalem , Thomas Petazzoni , Jason Cooper , Tawfik Bayouk , Andrew Lunn , Wim Van Sebroeck , Gregory Clement Subject: Re: [PATCH v2 06/15] watchdog: orion: Remove unneeded BRIDGE_CAUSE clear Message-ID: <20140122225654.GB30763@localhost> References: <1390295561-3466-1-git-send-email-ezequiel.garcia@free-electrons.com> <1390295561-3466-7-git-send-email-ezequiel.garcia@free-electrons.com> <20140121233537.GS18269@obsidianresearch.com> <20140122164904.GB27273@localhost> <20140122173417.GT18269@obsidianresearch.com> <52E02AB6.7040104@gmail.com> <20140122205213.GW18269@obsidianresearch.com> <20140122221237.GA30763@localhost> <20140122223117.GX18269@obsidianresearch.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: QUOTED-PRINTABLE In-Reply-To: <20140122223117.GX18269@obsidianresearch.com> Sender: linux-watchdog-owner@vger.kernel.org List-Id: linux-watchdog@vger.kernel.org On Wed, Jan 22, 2014 at 03:31:17PM -0700, Jason Gunthorpe wrote: > On Wed, Jan 22, 2014 at 07:12:38PM -0300, Ezequiel Garcia wrote: > > On Wed, Jan 22, 2014 at 01:52:13PM -0700, Jason Gunthorpe wrote: > > > > Clearing BRIDGE_CAUSE will only clear all currently pending ups= tream > > > > IRQs, of course. If WDT IRQ will be re-raised right after that = in > > > > BRIDGE_CAUSE depends on the actual HW implementation, i.e. we d= o no > > > > clear the causing IRQ itself but just what it raised in BRIDGE_= CAUSE. > > >=20 > > > Which is why it makes no sense to clear it one time at kernel sta= rt. > > >=20 > >=20 > > So, it seems we need to handle irq_startup(), as you suggested. > > I've just tested the attached patch, and it's working fine: the dri= ver's > > probe() fully stops the watchdog, and then request_irq() acks and > > pending interrupts, through the added irq_startup(). > >=20 > > How does it look? >=20 > Looks sane to me. >=20 > I looked some more and there are other drivers (eg irq-metag-ext) tha= t > take this same approach. >=20 Yup, I took that one as a starting point. [..] > I looked at the irq-orion driver a bit more and noticed this: >=20 > ret =3D irq_alloc_domain_generic_chips(domain, nrirqs, 1, np-= >name, > handle_level_irq, clr, 0, IRQ_GC_INIT_MA= SK_CACHE); > ^^^^^^^^^^^^^^^^^^^^^ > Shouldn't it be handle_edge_irq? Otherwise who is calling irq_ack? Ho= w > does this work at all? :) >=20 I'm not familiar with the differences between handle_level_irq and handle_edge_irq, but -AFAICS- both seem to ack the IRQ. In fact handle_level_irq(), masks and acks the IRQ as the first thing. --=20 Ezequiel Garc=C3=ADa, Free Electrons Embedded Linux, Kernel and Android Engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-watchdo= g" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html