From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Simek Subject: Re: [PATCH v2] microblaze: Change NO_IRQ to 0 Date: Tue, 20 Dec 2011 10:52:08 +0100 Message-ID: <4EF05AC8.8040707@monstr.eu> References: <1324304394-5655-1-git-send-email-monstr@monstr.eu> <4EEFC38C.4010201@gmail.com> Reply-To: monstr@monstr.eu Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4EEFC38C.4010201@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Ryan Mallon Cc: linux-kernel@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, Grant Likely , Rob Herring List-Id: devicetree@vger.kernel.org >> As has been discussed many times[1], Using NO_IRQ set to anything other >> than 0 is bug waiting to happen since many drivers follow the pattern >> "if (!irq)" for testing whether or not an irq has been set. >> >> This patch changes the Microblaze NO_IRQ setting from -1 to 0 to bring >> it in line with most of the rest of the kernel. It also prepares for >> Microblaze eventually supporting multiple interrupt controllers by >> breaking the assumption that hwirq# == Linux IRQ#. The Linux IRQ >> number is just a cookie with no guarantee of a direct relationship >> with the hardware irq arrangement. >> >> At this point, Microblaze interrupt handling only supports only one >> instance of one kind of interrupt controller (xilinx_intc). This change >> shouldn't affect any architecture code outside of the interrupt >> controller driver and the irq_of mapping. >> >> Updated to 3.2 and to use irq_data.hwirq by Rob Herring. >> Tested and fixed by Michal Simek. >> >> [1] http://lkml.org/lkml/2005/11/21/221 >> >> Signed-off-by: Grant Likely >> Signed-off-by: Rob Herring >> Signed-off-by: Michal Simek > > > >> extern unsigned int nr_irq; >> >> -#define NO_IRQ (-1) >> +#define NO_IRQ 0 > > IIUC, NO_IRQ should actually be removed in favour of testing against > zero explictly. On Linus' latest tree there are three appearances of > NO_IRQ in arch/microblaze: this definition and two uses and > arch/microblaze/pci/pci-common.c. The latter should be removed by this > patch. I assume there are still uses of NO_IRQ in drivers used by > microblaze which prevent removal of NO_IRQ completely? yeah, there are some drivers which we share with ppc. I will look at/fix them and then remove NO_IRQ from arch. drivers/net/ethernet/xilinx/xilinx_emaclite.c:1132: if (rc == NO_IRQ) { drivers/net/ethernet/xilinx/ll_temac_main.c:1080: if ((lp->rx_irq == NO_IRQ) || (lp->tx_irq == NO_IRQ)) { drivers/input/serio/xilinx_ps2.c:256: if (of_irq_to_resource(ofdev->dev.of_node, 0, &r_irq) == NO_IRQ) { drivers/block/xsysace.c:459: if (ace->irq == NO_IRQ) drivers/block/xsysace.c:1037: if (ace->irq != NO_IRQ) { drivers/block/xsysace.c:1042: ace->irq = NO_IRQ; drivers/block/xsysace.c:1089: if (ace->irq != NO_IRQ) drivers/block/xsysace.c:1159: int irq = NO_IRQ; Thanks, Michal -- Michal Simek, Ing. (M.Eng) w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/ Microblaze U-BOOT custodian