<html> <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#FFFFFF" text="#000000"> Couldn't resist connecting to my machine over VNC even though I'm not home. So, I booted it with the new patch and see that while you HAVE found the bug, the new register addresses still seem to be wrong. Instead of the audio registers containing their default, pre-filled, standard 2-speaker configuration, it's now being overwritten - which is good. With garbage - which is bad. ;-) One possible cause is that the SandyBridge addresses shouldn't use the same register addresses as IvyBridge after all. This will have to be double checked. Instead of /proc/asound/card0/eld#3.0 containing the default 2-speaker configuration, it now contains: monitor_present 1 eld_valid 1 monitor_name connection_type HDMI eld_version [0x0] reserved edid_version [0x0] no CEA EDID Timing Extension block present manufacture_id 0x0 product_id 0x0 port_id 0x0 support_hdcp 0 support_ai 0 audio_sync_delay 0 speakers [0x0] sad_count 0 You can see that the data is obviously zeroed out, and I bet it's due to a misaligned address. Booting with drm.debug=6 produced the attached log file which I've included for completeness. However, there's nothing strange in it. Christopher On 11/9/11 10:00 AM, Christopher White wrote: <blockquote cite="mid:4EBA4130.7010401@pulseforce.com" type="cite"> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> Good day, Fengguang! Great work! This sounds very promising! I went through the ELD parsing code myself (drm_edid_to_eld), as my programmer mind's curiosity killed me even though I didn't really have time for it, and I could see that it grabs the CEA extension block, grabs the monitor name string, then goes through each data block collection, copying all short descriptor data for each of the block types we're interested in. Good and clean code. So, I came to the same conclusion - that the parsing code was completely correct. I'm therefore very happy to hear that you've found the real problem; trying to write the ELD structure to the wrong audio registers on SandyBridge. Yep, that HAS to be it! I've applied the patch and the kernel is currently being re-built, but I've got to leave home so I won't report back until later today. However, I am confident that you've found the true cause of the problem. Superb work once again! You're going to make a lot of Home Theater PC owners very happy. Christopher White On 11/9/11 7:59 AM, Wu Fengguang wrote: <blockquote cite="mid:20111109065953.GB28238@localhost" type="cite"> <pre wrap="">Hi Christopher, I don't find anything wrong with the ELD parsing code, however I do find a bug that prevented ELD from being passed to the audio driver on SandyBridge. I just posted the fix. For your convenience, it's attached in this email too. Thanks, Fengguang On Fri, Oct 28, 2011 at 03:57:23AM +0800, Christopher White wrote: </pre> <blockquote type="cite"> <pre wrap="">There appears to be some issues with the patch? I'm on SandyBridge and using the HD3000's HDMI. I've now tried manually merging the ELD patch (both files Wu Fengguang submitted) and compiling Kernel 3.0.4. I've also tried drm-intel-next Kernel 3.1 pre-built from <a moz-do-not-send="true" class="moz-txt-link-freetext" href="http://kernel.ubuntu.com/%7Ekernel-ppa/mainline/drm-intel-next/current/">http://kernel.ubuntu.com/~kernel-ppa/mainline/drm-intel-next/current/</a> as I knew it was built from keithp's latest drm-intel-next repository. Both of these methods had the patch applied, yet neither were able to read the ELD correctly from my Onkyo TX-SR607 receiver. If I manually dump the EDID from my receiver and analyze it with Monitor Asset Manager (by EnTech Taiwan), it shows that the ELD contains an 8 channel specification up to 192 kHz, and that's what's being exposed over HDMI to the Intel graphics adapter, yet this isn't detected. It just plain isn't being read, and is falling back to the default 2ch 16kHz configuration. It's exactly as it was in the past, before this patch attempt. You can see my 256 byte EDID dump, straight from the receiver, over at: <a moz-do-not-send="true" class="moz-txt-link-freetext" href="http://www.pulseforce.com/node/edid.dump">http://www.pulseforce.com/node/edid.dump</a> It shows exactly what the receiver is exposing over HDMI, proving that it's not the device that's at fault. Any ideas what's wrong? Here's the HDMI messages from the startup log: HDMI status: Pin=7 Presence_Detect=1 ELD_Valid=1 HDMI: detected monitor at connection type HDMI HDMI: available speakers: FL/FR HDMI: supports coding type LPCM: channels = 2, rates = 44100 48000 88200, bits = 16 HDMI hot plug event: Pin=7 Presence_Detect=1 ELD_Valid=1 HDMI status: Pin=7 Presence_Detect=1 ELD_Valid=1 input: HDA Intel PCH HDMI/DP as /devices/pci0000:00/0000:00:1b.0/sound/card0/input9 HDMI: detected monitor at connection type HDMI HDMI: available speakers: FL/FR HDMI: supports coding type LPCM: channels = 2, rates = 44100 48000 88200, bits = 16 HDMI hot plug event: Pin=7 Presence_Detect=1 ELD_Valid=1 HDMI status: Pin=7 Presence_Detect=1 ELD_Valid=1 HDMI: detected monitor at connection type HDMI HDMI: available speakers: FL/FR HDMI: supports coding type LPCM: channels = 2, rates = 44100 48000 88200, bits = 16 Christopher White</pre> </blockquote> </blockquote> </blockquote> </body> </html>