From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Gerasiov Subject: Boot IRQ issue on Intel C602J (Advantech ASMB-822) Date: Mon, 8 Feb 2016 12:40:04 +0300 Message-ID: <20160208124004.5a20494f@brick.gerasiov.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit To: linux-rt-users@vger.kernel.org Return-path: Received: from mail.gerasiov.net ([158.250.17.72]:48861 "EHLO mail.gerasiov.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751098AbcBHJtZ (ORCPT ); Mon, 8 Feb 2016 04:49:25 -0500 Received: from mail.gerasiov.net (mail.gerasiov.net [127.0.0.1]) by mail.gerasiov.net (Postfix) with ESMTP id 4021AA00E2 for ; Mon, 8 Feb 2016 12:40:05 +0300 (MSK) Received: from brick.gerasiov.net (unknown [192.168.131.72]) by mail.gerasiov.net (Postfix) with ESMTPSA id 1E821A00AB for ; Mon, 8 Feb 2016 12:40:05 +0300 (MSK) Sender: linux-rt-users-owner@vger.kernel.org List-ID: Hello there. We are using 3.10.74-rt79 in our system and found some problem with Advantech ASMB-822 motherboard. It's Intel C602J based m/b with 2 IO-APIC. We have 2 special PCIe adapters installed. They use legacy interrupts through APIC. On 3.10.74 one of adapter generate only several (~10) interrupts and then halts. As I discovered, it works ok, but no interrupts was delivered. The same time (but after device stops receiving irqs) boot irqs occur and irq 16 got disabled by the kernel. I tried 3.18.25 with the same result. Right now I'm running 4.4.1-rt4 and finally it works, but there are still boot irqs and kernel disables IRQ 16 because of them. So I need some ideas, how to deal with boot interrupts on this chipset. May be to add workaround like masking boot irq together with IO-APIC irq. PS If someone could give a clue, what was changed in 4.4.1 from 3.18 that would be great. (As I'm not sure we could switch production system to 4.4.1 soon, and I'd like to backport this change set to old kernel if possible.) -- Best regards, Alexander Gerasiov Contacts: e-mail: gq@cs.msu.su Homepage: http://gerasiov.net Skype: gerasiov PGP fingerprint: 04B5 9D90 DF7C C2AB CD49 BAEA CA87 E9E8 2AAC 33F1