From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: Re: [PATCH] genirq: provide means to retrigger parent Date: Wed, 24 Oct 2012 00:36:47 +0200 (CEST) Message-ID: References: <1350425269-11489-1-git-send-email-khilman@deeprootsystems.com> <20121016221502.GY28061@n2100.arm.linux.org.uk> <871ugo7rqv.fsf@deeprootsystems.com> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <871ugo7rqv.fsf@deeprootsystems.com> Sender: linux-kernel-owner@vger.kernel.org To: Kevin Hilman Cc: Russell King - ARM Linux , linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-omap@vger.kernel.org On Tue, 23 Oct 2012, Kevin Hilman wrote: > Russell King - ARM Linux writes: > > > On Tue, Oct 16, 2012 at 03:07:49PM -0700, Kevin Hilman wrote: > >> From: Thomas Gleixner > >> > >> Attempts to retrigger nested threaded IRQs currently fail because they > >> have no primary handler. In order to support retrigger of nested > >> IRQs, the parent IRQ needs to be retriggered. > >> > >> To fix, when an IRQ needs to be resent, if the interrupt has a parent > >> IRQ and runs in the context of the parent IRQ, then resend the parent. > >> > >> Also, handle_nested_irq() needs to clear the replay flag like the > >> other handlers, otherwise check_irq_resend() will set it and it will > >> never be cleared. Without clearing, it results in the first resend > >> working fine, but check_irq_resend() returning early on subsequent > >> resends because the replay flag is still set. > >> > >> Problem discovered on ARM/OMAP platforms where a nested IRQ that's > >> also a wakeup IRQ happens late in suspend and needed to be retriggered > >> during the resume process. > >> > >> Reported-by: Kevin Hilman > >> Tested-by: Kevin Hilman > >> [khilman@ti.com: changelog edits, clear IRQS_REPLAY in handle_nested_irq()] > >> Signed-off-by: Thomas Gleixner > > > > Umm, we also have the converse situation. We have platforms where the > > resend has to be done from the child IRQ, and the parent must not be > > touched. I hope that doesn't break those. > > I'm assuming the child IRQs you're concerned with are not threaded, > right? This patch only addresses nested, threaded IRQs, and these don't > have a primary handler to run at all, so cannot do any triggering. And it involves that you activly set the parent irq via the new interface: irq_set_parent() You don't have that yet or you don't use that in your future changes, then you're good. :) Thanks, tglx