From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Hounschell Subject: Re: Intel graphics drm issue? Date: Sun, 14 Oct 2012 06:34:56 -0400 Message-ID: <507A9550.1060309@cfl.rr.com> References: <507812E8.3060607@compro.net> <20121012231459.166e29fd@neptune.home> <5079B97C.7020401@cfl.rr.com> <5079BE5C.8020401@cfl.rr.com> <20121014104138.7e8a9c59@neptune.home> Reply-To: dmarkh@cfl.rr.com Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20121014104138.7e8a9c59@neptune.home> Sender: linux-kernel-owner@vger.kernel.org To: =?UTF-8?B?QnJ1bm8gUHLDqW1vbnQ=?= Cc: markh@compro.net, linux-kernel@vger.kernel.org, Intel Graphics Development List-Id: intel-gfx@lists.freedesktop.org On 10/14/2012 04:41 AM, Bruno Pr=C3=A9mont wrote: > Hi Mark, > > On Sat, 13 October 2012 Mark Hounschell wrote: >> On 10/13/2012 02:57 PM, Mark Hounschell wrote: >>> On 10/12/2012 05:14 PM, Bruno Pr=C3=A9mont wrote: >>>>> TV - LG 42lb9df >>>>> PC - intel DH77DF motherboard >>>> >>> I have another AMD based PC here with an nvidia card and HDMI port.= Using >>> the nvidia driver, it boots up with no output to the tv until X sta= rts. >>> Once X starts I get my kdm login screen. All is well except the res= olution >>> is 800x600 and I have no VTs. I suspect if I had a properly configu= red >>> xorg.conf file, my resolution would be what I defined in it and wor= k. >>> >>> Using the nouveau driver, I get nothing but "no signal" on the tv. = Just >>> like the the intel box, except no EDID messages in the log file. I'= ve >>> attached a dmesg outputs for each config. >>> >>> Back on the Intel machine. I boot up with a normal monitor connecte= d to the >>> DVI port of the PC. Then at the kdm login screen, I disconnect the = DVI >>> cable from the PC and connect the TV to the PCs DVI port using a DV= I/HDMI >>> adapter. I get a beautiful 1600x1200 resolution screen on the TV. T= his does >>> not happen using the PC HDMI port. >>> >> >> One other thing I failed to mention. If i connect the TV HDMI to the= Intel >> boards DVI port using the adapter, at power up I get all the BIOS me= ssages >> and can enter the BIOS and all is fine. But when I let it boot all t= he way >> up like this, I get nothing but "no signal" after leaving BIOS mode. >> Turning the tv on/off, cable plug/unplug does not help. > > Did you also try the DVI-HDMI adapter cable with the nVidia card? > No, I didn't try that. I certainly can though. > But will all that info I would say the issues is at the side of you T= V that > just does not provide (valid) EDID information, thus the driver does = not know > what the display supports. > > The 1600x1200 when switching DVI displays on Intel would seem like th= e driver > just kept on display what it had, not reconfiguring anything. > Right, that's what I thought was happening. But at least it tells me th= at=20 the tv can in fact "probably" operate in whatever resolution I force it= to.=20 Is there no way, like in the past we had to do, to just not care what t= he=20 tv/monitor says or does, and just use a fixed resolution? > For the 800x600 of nVidia, that kind of the default fallback when dis= play > capabilities are unknown as any remotely recent display should alt le= ast be > capable to understand that. > Yep, that's what I figured here too. nvidia provides a "default/fallbac= k"=20 so you can at least access the desktop. Seems a reasonable thing, no? > > Your best solution is probably to write an EDID blob (or reuse one yo= u find > somewhere) that provides at least one mode matching your TV's native = mode > (probably full-HD). > > Google suggested the following document: > http://www.jordansmanuals.com/ServiceManuals%5CLG%5CTV%5CLCD%5C42LB9D= =46%5C42LB9DF%20Service%20Manual.pdf > which on page 13/14 shows the full EDID blob for the various HDMI out= puts of the > TV. You may want to read that document, convert the EDID blobs to 512= bytes binary > files and hell DRM core to use the right one via module/kernel cmdlin= e option: > > drm_kms_helper.edid_firmware=3Dedid/lg42lb9df.edid > or > modprobe drm-kms-helper edid_firmware=3Dedid/lg42lb9df.edid > > where > /lib/firmware/edid/lg42lb9df.edid > is the 512-bytes EDID blob created according to data from above manua= l. > (note, that will only work for intel, radeon and nouveau drivers but = will > not work for closed drivers of AMD/nVidia) > Thanks for this tip. I will investigate this asap. > PS: If you didn't already do so, try all of the HDMI connectors or th= e TV and > if available, also two distinct HDMI cables of different brand. Did all that, first thing. Thanks Mark