From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Andrzej Siewior Subject: Re: 3.10.9-rt5 with Atmel AT91SAM9G25 SoC triggers "Trying to free already-free IRQ 1" Date: Fri, 18 Oct 2013 16:03:47 +0200 Message-ID: <20131018140346.GA14569@linutronix.de> References: <20131011100951.GC6983@linutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Michael Langfinger , "linux-rt-users@vger.kernel.org" To: Sami =?utf-8?Q?Pietik=C3=A4inen?= Return-path: Received: from www.linutronix.de ([62.245.132.108]:40761 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755994Ab3JRODs convert rfc822-to-8bit (ORCPT ); Fri, 18 Oct 2013 10:03:48 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-rt-users-owner@vger.kernel.org List-ID: * Sami Pietik=C3=A4inen | 2013-10-14 07:24:20 [+0000]: >Hello Sebastian Hello Sami, >>The problem does not look -RT specific. > >I would say that at least the "Trying to free already-free IRQ 1" warn= ing is somehow -RT specific. When I tested the 3.6.9 kernel without the= RT patch there were no warnings (using SAMA5D35). The same warning Mic= hael is having appeared only after applying the patch. However, the oth= er problems Michael is having might also be something else. > >>I don't understand why uart tries over and over to request that inter= rupt but it simply doesn't work. >>I am a little confused why at91 is having everything (or more than on= e >>device) is on irq 16. It should have only one device on each interrup= t since they have usually dedicated irq lines. > >arm-at91-tclib-default-to-tclib-timer-for-rt.patch has the following c= omment: >"RT is not too happy about the shared timer interrupt in AT91 >devices. Default to tclib timer for RT." > >Snippet from SAMA5D35 datasheet: >"Usually, the Debug Unit interrupt line connects to the interrupt sour= ce 1 of the AIC, which may be shared with the real-time clock, the syst= em timer interrupt lines and other system peripheral interrupts" > >The debug unit also has UART which is probably Michael's ttyS0. Argh. I missed that detail. So that explains why UART and the timer share the same interrupt number. Is that timer really disabled in your config? > >BR, >Sami Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-rt-user= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html