From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Hurley Subject: Re: Which is better to specify console, "console= " or "stdout-path" ? Date: Wed, 21 Oct 2015 09:02:43 -0400 Message-ID: <56278CF3.9010400@hurleysoftware.com> References: <562753A6.3070107@arm.com> <56278911.9050704@hurleysoftware.com> <56278AFD.8000505@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <56278AFD.8000505-5wv7dgnIgG8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sudeep Holla , Masahiro Yamada , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel , linux-serial-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On 10/21/2015 08:54 AM, Sudeep Holla wrote: > > > On 21/10/15 13:46, Peter Hurley wrote: >> On 10/21/2015 04:58 AM, Sudeep Holla wrote: >>> On 21/10/15 06:09, Masahiro Yamada wrote: >>>> I think there exist two ways to specify the console port and baudrate. >>>> >>>> >>>> [1] Specify console in bootargs >>>> >>>> chosen { >>>> bootargs = "console=ttyS0,115200"; >>>> }; >>>> >>>> >>>> [2] Specify stdout-path >>>> >>>> chosen { >>>> stdout-path = "serial0:115200n8"; >>> >>> This will work for even early/boot console, so this is better than >>> option [1] >> >> Be aware that options specified via /chosen/stdout-path are >> currently ignored by earlycon. There were some hiccups getting the >> initial support upstream; when 4.4 hits mainline, I'll resubmit >> my series that implements the of_serial i/o properties and >> options passthrough to earlycon setup. >> > > Yes I am aware of that. The others to which my email was addressed might not know that. > IIUC it's in -next now and works fine for me. Well, the fix in -next doesn't actually do anything wrt earlycon baud rate; those changes were part of a larger series that depends on the fix in -next. Regards, Peter Hurley > But having stdout-path in the DTS won't hinder normal console in anyway. > So I prefer it even without the patch you are referring(to support early > console parsing stdout-path) -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html