From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754275AbaIQIjH (ORCPT ); Wed, 17 Sep 2014 04:39:07 -0400 Received: from www.linutronix.de ([62.245.132.108]:47369 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751842AbaIQIjC (ORCPT ); Wed, 17 Sep 2014 04:39:02 -0400 Message-ID: <5419489C.9090607@linutronix.de> Date: Wed, 17 Sep 2014 10:38:52 +0200 From: Sebastian Andrzej Siewior User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.0 MIME-Version: 1.0 To: Tony Lindgren CC: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, balbi@ti.com, gregkh@linuxfoundation.org Subject: Re: [PATCH 00/16 v9] omap 8250 based uart + DMA References: <1410377411-26656-1-git-send-email-bigeasy@linutronix.de> <20140912224324.GK18849@atomide.com> <5416D2A0.5020407@linutronix.de> <541833C0.5020106@linutronix.de> <20140916164858.GA1580@atomide.com> <20140916213043.GB6672@atomide.com> In-Reply-To: <20140916213043.GB6672@atomide.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit 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 09/16/2014 11:30 PM, Tony Lindgren wrote: > Found one more issue when booting on 2420 n8x0, maybe something to do > with runtime PM? To some degree, yes. > [ 4.770507] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM e3a02000 mov r2, #0 ee072fba mcr 15, 0, r2, cr7, cr10, {5} e3a01001 mov r1, #1 f5d3f000 pld [r3] =>e1d30f9f ldrexb r0, [r3] That ldrexb is part of the xchg() function in serial8250_rpm_get_tx(). So it looks like 2420 n8x0 does not understand ldrexb but the inline assembly decided that it should. This OMAP2420 should be ARM1136 / ARMv6. The ARM1136J(F)-S TRM says for ldrexb: "This command is only available from the rev1 (r1p0) release of the ARM1136JF-S processor." So it looks like the CPU should know what to do when this opcode comes around. > > Regards, > > Tony > Sebastian From mboxrd@z Thu Jan 1 00:00:00 1970 From: bigeasy@linutronix.de (Sebastian Andrzej Siewior) Date: Wed, 17 Sep 2014 10:38:52 +0200 Subject: [PATCH 00/16 v9] omap 8250 based uart + DMA In-Reply-To: <20140916213043.GB6672@atomide.com> References: <1410377411-26656-1-git-send-email-bigeasy@linutronix.de> <20140912224324.GK18849@atomide.com> <5416D2A0.5020407@linutronix.de> <541833C0.5020106@linutronix.de> <20140916164858.GA1580@atomide.com> <20140916213043.GB6672@atomide.com> Message-ID: <5419489C.9090607@linutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 09/16/2014 11:30 PM, Tony Lindgren wrote: > Found one more issue when booting on 2420 n8x0, maybe something to do > with runtime PM? To some degree, yes. > [ 4.770507] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM e3a02000 mov r2, #0 ee072fba mcr 15, 0, r2, cr7, cr10, {5} e3a01001 mov r1, #1 f5d3f000 pld [r3] =>e1d30f9f ldrexb r0, [r3] That ldrexb is part of the xchg() function in serial8250_rpm_get_tx(). So it looks like 2420 n8x0 does not understand ldrexb but the inline assembly decided that it should. This OMAP2420 should be ARM1136 / ARMv6. The ARM1136J(F)-S TRM says for ldrexb: "This command is only available from the rev1 (r1p0) release of the ARM1136JF-S processor." So it looks like the CPU should know what to do when this opcode comes around. > > Regards, > > Tony > Sebastian