Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933127AbaD1TjH (ORCPT ); Mon, 28 Apr 2014 15:39:07 -0400 Received: from www.linutronix.de ([62.245.132.108]:42411 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932272AbaD1TjE (ORCPT ); Mon, 28 Apr 2014 15:39:04 -0400 Date: Mon, 28 Apr 2014 21:39:15 +0200 (CEST) From: Thomas Gleixner To: Sebastian Hesselbarth cc: Jason Cooper , Andrew Lunn , Gregory Clement , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RESEND 3/3] irqchip: orion: reverse irq handling priority In-Reply-To: <1398540855-27367-4-git-send-email-sebastian.hesselbarth@gmail.com> Message-ID: References: <1398540855-27367-1-git-send-email-sebastian.hesselbarth@gmail.com> <1398540855-27367-4-git-send-email-sebastian.hesselbarth@gmail.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 26 Apr 2014, Sebastian Hesselbarth wrote: > Non-DT irq handlers were working through irq causes from most-significant > to least-significant bit, while DT irqchip driver does it the other way > round. This revealed some more HW issues on Kirkwood peripheral IP, where > spurious sdio irqs can happen although IP's irq enable registers are all > zero. Although, not directly related with the described issue, reverse > irq bit handling back to original order by replacing ffs() with fls(). So why are we reverting to the original order? The explanation above is just confusing. Thanks, tglx > Signed-off-by: Sebastian Hesselbarth > Acked-by: Jason Cooper > --- > Cc: Jason Cooper > Cc: Andrew Lunn > Cc: Gregory Clement > Cc: Thomas Gleixner > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > --- > drivers/irqchip/irq-orion.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/irqchip/irq-orion.c b/drivers/irqchip/irq-orion.c > index e25f246cd2fb..34d18b48bb78 100644 > --- a/drivers/irqchip/irq-orion.c > +++ b/drivers/irqchip/irq-orion.c > @@ -42,7 +42,7 @@ __exception_irq_entry orion_handle_irq(struct pt_regs *regs) > u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) & > gc->mask_cache; > while (stat) { > - u32 hwirq = ffs(stat) - 1; > + u32 hwirq = __fls(stat); > u32 irq = irq_find_mapping(orion_irq_domain, > gc->irq_base + hwirq); > handle_IRQ(irq, regs); > @@ -117,7 +117,7 @@ static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc) > gc->mask_cache; > > while (stat) { > - u32 hwirq = ffs(stat) - 1; > + u32 hwirq = __fls(stat); > > generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq)); > stat &= ~(1 << hwirq); > -- > 1.9.1 > > -- 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/