From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Andrzej Siewior Subject: Re: [PATCH 05/15] tty: serial: Add 8250-core based omap driver Date: Thu, 21 Aug 2014 13:00:59 +0200 Message-ID: <53F5D16B.4030007@linutronix.de> References: <1408124563-31541-1-git-send-email-bigeasy@linutronix.de> <1408124563-31541-6-git-send-email-bigeasy@linutronix.de> <20140815210716.GE9239@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from www.linutronix.de ([62.245.132.108]:57193 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754371AbaHULB1 (ORCPT ); Thu, 21 Aug 2014 07:01:27 -0400 In-Reply-To: <20140815210716.GE9239@atomide.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tony Lindgren , Greg Kroah-Hartman 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, Vinod Koul On 08/15/2014 11:07 PM, Tony Lindgren wrote: > Nice, now it mostly works for me with off-idle too :) That is as long > as I have the DMA channels commented out in the .dts file. >=20 > And I'm still seeing an occasional hang with pstore console just > showing: >=20 > [ 289.076538] In-band Error seen by MPU at address 0 > [ 289.076538] ------------[ cut here ]------------ > [ 289.076568] WARNING: CPU: 0 PID: 99 at drivers/bus/omap_l3_smx.c:1= 62 omap3_l3_app_irq+0xdc/0x134() > [ 289.076599] Modules linked in: > [ 289.076599] CPU: 0 PID: 99 Comm: test-idle-off-8 Tainted: G = W 3.16.0+ #510 > [ 289.076629] [] (unwind_backtrace) from [] (sho= w_stack+0x20/0x24) > [ 289.076660] [] (show_stack) from [] (dump_stac= k+0x88/0xa4) Okay. So this backtrace does not show more like from where the access is happening? > Which most likely means there's still some glitch with the > runtime PM somewhere and registers are being accessed when > not clocked. I _think_ I did not see it when I did not have > console=3DttyS2,115200 in my cmdline but was using just pstore > console. >=20 >> The device name is ttyS based instead of ttyO. If a ttyO based node = name >> is required please ask udev for it. If both driver are activated (th= is >> and omap-serial) then this serial driver will take control over the >> device due to the link order >=20 > That's still not going to help with the existing kernel cmdlines > and existing installs.. I wonder if we can just do a minimal > dummy serial-omap.c that just proxies all the ttyO read/write > access to ttyS? Hmm. So you are not a friend of the udev solution?. For now the driver is "default n" and you have to explicit enable it and _then_ you should be able to update your command line, etc. If I introduce a kernel proxy for compatibility I assume that people will wake up once that compatibility piece is gone. However, if you insist=85 I tried to make a symlink but nobody does thi= s in kernel. The "rtc -> rtc0" and friends seem to come from udev _or_ distro. So I sff could a second device node with the same major/minor. That would work for userland but not for the kernel console=85 So we ne= ed a proxy-console for this. Before I spent time on this proxy-console I would like to hear from Gre= g that he is okay with this. >=20 > Regards, >=20 > Tony Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-omap" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: bigeasy@linutronix.de (Sebastian Andrzej Siewior) Date: Thu, 21 Aug 2014 13:00:59 +0200 Subject: [PATCH 05/15] tty: serial: Add 8250-core based omap driver In-Reply-To: <20140815210716.GE9239@atomide.com> References: <1408124563-31541-1-git-send-email-bigeasy@linutronix.de> <1408124563-31541-6-git-send-email-bigeasy@linutronix.de> <20140815210716.GE9239@atomide.com> Message-ID: <53F5D16B.4030007@linutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/15/2014 11:07 PM, Tony Lindgren wrote: > Nice, now it mostly works for me with off-idle too :) That is as long > as I have the DMA channels commented out in the .dts file. > > And I'm still seeing an occasional hang with pstore console just > showing: > > [ 289.076538] In-band Error seen by MPU at address 0 > [ 289.076538] ------------[ cut here ]------------ > [ 289.076568] WARNING: CPU: 0 PID: 99 at drivers/bus/omap_l3_smx.c:162 omap3_l3_app_irq+0xdc/0x134() > [ 289.076599] Modules linked in: > [ 289.076599] CPU: 0 PID: 99 Comm: test-idle-off-8 Tainted: G W 3.16.0+ #510 > [ 289.076629] [] (unwind_backtrace) from [] (show_stack+0x20/0x24) > [ 289.076660] [] (show_stack) from [] (dump_stack+0x88/0xa4) Okay. So this backtrace does not show more like from where the access is happening? > Which most likely means there's still some glitch with the > runtime PM somewhere and registers are being accessed when > not clocked. I _think_ I did not see it when I did not have > console=ttyS2,115200 in my cmdline but was using just pstore > console. > >> The device name is ttyS based instead of ttyO. If a ttyO based node name >> is required please ask udev for it. If both driver are activated (this >> and omap-serial) then this serial driver will take control over the >> device due to the link order > > That's still not going to help with the existing kernel cmdlines > and existing installs.. I wonder if we can just do a minimal > dummy serial-omap.c that just proxies all the ttyO read/write > access to ttyS? Hmm. So you are not a friend of the udev solution?. For now the driver is "default n" and you have to explicit enable it and _then_ you should be able to update your command line, etc. If I introduce a kernel proxy for compatibility I assume that people will wake up once that compatibility piece is gone. However, if you insist? I tried to make a symlink but nobody does this in kernel. The "rtc -> rtc0" and friends seem to come from udev _or_ distro. So I sff could a second device node with the same major/minor. That would work for userland but not for the kernel console? So we need a proxy-console for this. Before I spent time on this proxy-console I would like to hear from Greg that he is okay with this. > > Regards, > > Tony Sebastian From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754645AbaHULB3 (ORCPT ); Thu, 21 Aug 2014 07:01:29 -0400 Received: from www.linutronix.de ([62.245.132.108]:57193 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754371AbaHULB1 (ORCPT ); Thu, 21 Aug 2014 07:01:27 -0400 Message-ID: <53F5D16B.4030007@linutronix.de> Date: Thu, 21 Aug 2014 13:00:59 +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 , Greg Kroah-Hartman 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, Vinod Koul Subject: Re: [PATCH 05/15] tty: serial: Add 8250-core based omap driver References: <1408124563-31541-1-git-send-email-bigeasy@linutronix.de> <1408124563-31541-6-git-send-email-bigeasy@linutronix.de> <20140815210716.GE9239@atomide.com> In-Reply-To: <20140815210716.GE9239@atomide.com> Content-Type: text/plain; charset=windows-1252 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 08/15/2014 11:07 PM, Tony Lindgren wrote: > Nice, now it mostly works for me with off-idle too :) That is as long > as I have the DMA channels commented out in the .dts file. > > And I'm still seeing an occasional hang with pstore console just > showing: > > [ 289.076538] In-band Error seen by MPU at address 0 > [ 289.076538] ------------[ cut here ]------------ > [ 289.076568] WARNING: CPU: 0 PID: 99 at drivers/bus/omap_l3_smx.c:162 omap3_l3_app_irq+0xdc/0x134() > [ 289.076599] Modules linked in: > [ 289.076599] CPU: 0 PID: 99 Comm: test-idle-off-8 Tainted: G W 3.16.0+ #510 > [ 289.076629] [] (unwind_backtrace) from [] (show_stack+0x20/0x24) > [ 289.076660] [] (show_stack) from [] (dump_stack+0x88/0xa4) Okay. So this backtrace does not show more like from where the access is happening? > Which most likely means there's still some glitch with the > runtime PM somewhere and registers are being accessed when > not clocked. I _think_ I did not see it when I did not have > console=ttyS2,115200 in my cmdline but was using just pstore > console. > >> The device name is ttyS based instead of ttyO. If a ttyO based node name >> is required please ask udev for it. If both driver are activated (this >> and omap-serial) then this serial driver will take control over the >> device due to the link order > > That's still not going to help with the existing kernel cmdlines > and existing installs.. I wonder if we can just do a minimal > dummy serial-omap.c that just proxies all the ttyO read/write > access to ttyS? Hmm. So you are not a friend of the udev solution?. For now the driver is "default n" and you have to explicit enable it and _then_ you should be able to update your command line, etc. If I introduce a kernel proxy for compatibility I assume that people will wake up once that compatibility piece is gone. However, if you insist… I tried to make a symlink but nobody does this in kernel. The "rtc -> rtc0" and friends seem to come from udev _or_ distro. So I sff could a second device node with the same major/minor. That would work for userland but not for the kernel console… So we need a proxy-console for this. Before I spent time on this proxy-console I would like to hear from Greg that he is okay with this. > > Regards, > > Tony Sebastian