Re: [gentoo-user] DRM error: couldn't read SADs
On Saturday, 17 February 2018 10:33:15 GMT Peter Humphrey wrote: > On Tuesday, 13 February 2018 10:23:45 GMT Peter Humphrey wrote: > > On Tuesday, 13 February 2018 01:10:16 GMT Jack wrote: > > > It's been a long time since I've needed to do it, and it was also due > > > to a (cheap?) KVM switch, but I think there are two things that might > > > help. First, if you boot the PC with that monitor connected, it might > > > actually read the EDID data. Even if not, if you can capture it (one > > > time use of a straigt DVI or VGA cable?) you can save it tp a file > > > using x11-misc/read-edid, and then there is a way to get kernel/X to > > > read that EDID file at startup instead of trying and failing to get it > > > directly from the monitor. If you can't find a reference, I'll dig > > > and > > > try to figure out if it's kernel paramater or xorg.conf that you need > > > to mess with. > > > > Yes, I remember something along those lines - reading EDID from a file > > instead of the device. I don't think it's that simple though, as the > > screen is being driven at the right resolution. I just get half-a-dozen > > or so errors reported during a full day. > > > > I'm expecting the bits to make a direct connection to arrive today, so > > fingers crossed ... > > For the record, the more direct link (a cable with DisplayPort at one end > and HDMI at the other) has cleared the SAD problem... Ahem! Stupid boy; it only kept its head down for a couple of days. Now it seems to go a day or two between series of a few errors. -- Regards, Peter.
Re: [gentoo-user] DRM error: couldn't read SADs
On Tuesday, 13 February 2018 10:23:45 GMT Peter Humphrey wrote: > On Tuesday, 13 February 2018 01:10:16 GMT Jack wrote: > > It's been a long time since I've needed to do it, and it was also due > > to a (cheap?) KVM switch, but I think there are two things that might > > help. First, if you boot the PC with that monitor connected, it might > > actually read the EDID data. Even if not, if you can capture it (one > > time use of a straigt DVI or VGA cable?) you can save it tp a file > > using x11-misc/read-edid, and then there is a way to get kernel/X to > > read that EDID file at startup instead of trying and failing to get it > > directly from the monitor. If you can't find a reference, I'll dig and > > try to figure out if it's kernel paramater or xorg.conf that you need > > to mess with. > > Yes, I remember something along those lines - reading EDID from a file > instead of the device. I don't think it's that simple though, as the > screen is being driven at the right resolution. I just get half-a-dozen > or so errors reported during a full day. > > I'm expecting the bits to make a direct connection to arrive today, so > fingers crossed ... For the record, the more direct link (a cable with DisplayPort at one end and HDMI at the other) has cleared the SAD problem, but not the balance of the picture. And I'm left with no all-inclusive KVM. Those are problems for another day... -- Regards, Peter.
Re: [gentoo-user] DRM error: couldn't read SADs
On Tuesday, 13 February 2018 01:10:16 GMT Jack wrote: > It's been a long time since I've needed to do it, and it was also due > to a (cheap?) KVM switch, but I think there are two things that might > help. First, if you boot the PC with that monitor connected, it might > actually read the EDID data. Even if not, if you can capture it (one > time use of a straigt DVI or VGA cable?) you can save it tp a file > using x11-misc/read-edid, and then there is a way to get kernel/X to > read that EDID file at startup instead of trying and failing to get it > directly from the monitor. If you can't find a reference, I'll dig and > try to figure out if it's kernel paramater or xorg.conf that you need > to mess with. Yes, I remember something along those lines - reading EDID from a file instead of the device. I don't think it's that simple though, as the screen is being driven at the right resolution. I just get half-a-dozen or so errors reported during a full day. I'm expecting the bits to make a direct connection to arrive today, so fingers crossed ... -- Regards, Peter.
Re: [gentoo-user] DRM error: couldn't read SADs
On 2018.02.12 19:57, Peter Humphrey wrote: On Sunday, 11 February 2018 05:41:28 GMT 80x24 wrote: > On Sun, Feb 11, 2018 at 12:47 AM, > Peter Humphrey wrote: > > [drm:dce_v11_0_afmt_setmode] *ERROR* Couldn't read SADs: 0 > > [...] > > traps: plugin-containe[6833] general protection ip:7f0a2e1711b1 > > sp:7fff6f64dc30 error:0 in ld-2.25.so[7f0a2e15c000+23000] > > > > What is a SAD (other than a seasonal affective disorder)? That library > > comes from glibc, of which I've had 5 versions or revisions in that time > /** > * drm_edid_to_sad - extracts SADs from EDID > * @edid: EDID to parse > * @sads: pointer that will be set to the extracted SADs > * > * Looks for CEA EDID block and extracts SADs (Short Audio Descriptors) > fr$ > * > * Note: The returned pointer needs to be freed using kfree(). > * > * Return: The number of found SADs or negative number on error. > */ > > Considering the term ``EDID'' and some audio related words, I think > it's reading some info from your monitor. Hmm. Interesting. Looks like I'll have to revise my screen setup. It's a Samsung LED device with HDMI input. This box outputs HDMI too, but the other boxes I use it on output DVI, so by piecemeal development I've ended up with a four-port DVI switch, all connected with adapter cables. It seems likely that EDID is getting lost, and I may now also have a reason for the washed-out appearance of the screen. Modern websites with their pale colours are hard to read. Even the green of KMail's quoted text is hard. The other boxes I mentioned can also output VGA, and the screen can accept VGA too and switch between inputs. So I just need a two-port VGA switch and some cables. I've not long since thrown out all the old VGA stuff - damn! I knew I should never throw anything away. It's been a long time since I've needed to do it, and it was also due to a (cheap?) KVM switch, but I think there are two things that might help. First, if you boot the PC with that monitor connected, it might actually read the EDID data. Even if not, if you can capture it (one time use of a straigt DVI or VGA cable?) you can save it tp a file using x11-misc/read-edid, and then there is a way to get kernel/X to read that EDID file at startup instead of trying and failing to get it directly from the monitor. If you can't find a reference, I'll dig and try to figure out if it's kernel paramater or xorg.conf that you need to mess with. Jack
Re: [gentoo-user] DRM error: couldn't read SADs
On Sunday, 11 February 2018 05:41:28 GMT 80x24 wrote: > On Sun, Feb 11, 2018 at 12:47 AM, > Peter Humphrey wrote: > > [drm:dce_v11_0_afmt_setmode] *ERROR* Couldn't read SADs: 0 > > [...] > > traps: plugin-containe[6833] general protection ip:7f0a2e1711b1 > > sp:7fff6f64dc30 error:0 in ld-2.25.so[7f0a2e15c000+23000] > > > > What is a SAD (other than a seasonal affective disorder)? That library > > comes from glibc, of which I've had 5 versions or revisions in that time > /** > * drm_edid_to_sad - extracts SADs from EDID > * @edid: EDID to parse > * @sads: pointer that will be set to the extracted SADs > * > * Looks for CEA EDID block and extracts SADs (Short Audio Descriptors) > fr$ > * > * Note: The returned pointer needs to be freed using kfree(). > * > * Return: The number of found SADs or negative number on error. > */ > > Considering the term ``EDID'' and some audio related words, I think > it's reading some info from your monitor. Hmm. Interesting. Looks like I'll have to revise my screen setup. It's a Samsung LED device with HDMI input. This box outputs HDMI too, but the other boxes I use it on output DVI, so by piecemeal development I've ended up with a four-port DVI switch, all connected with adapter cables. It seems likely that EDID is getting lost, and I may now also have a reason for the washed-out appearance of the screen. Modern websites with their pale colours are hard to read. Even the green of KMail's quoted text is hard. The other boxes I mentioned can also output VGA, and the screen can accept VGA too and switch between inputs. So I just need a two-port VGA switch and some cables. I've not long since thrown out all the old VGA stuff - damn! I knew I should never throw anything away. Thanks for your help. -- Regards, Peter.
Re: [gentoo-user] DRM error: couldn't read SADs
On Sun, Feb 11, 2018 at 12:47 AM, Peter Humphrey wrote: > > [drm:dce_v11_0_afmt_setmode] *ERROR* Couldn't read SADs: 0 > [...] > traps: plugin-containe[6833] general protection ip:7f0a2e1711b1 > sp:7fff6f64dc30 error:0 in ld-2.25.so[7f0a2e15c000+23000] > > What is a SAD (other than a seasonal affective disorder)? That library comes > from glibc, of which I've had 5 versions or revisions in that time Never heard of it neither. Digging into the kernel source gives static void radeon_audio_write_sad_regs(struct drm_encoder *encoder) { struct drm_connector *connector = radeon_get_connector_for_encoder$ struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder); struct cea_sad *sads; int sad_count; if (!connector) return; sad_count = drm_edid_to_sad(radeon_connector_edid(connector), &sad$ if (sad_count <= 0) { DRM_ERROR("Couldn't read SADs: %d\n", sad_count); return; } BUG_ON(!sads); if (radeon_encoder->audio && radeon_encoder->audio->write_sad_regs) radeon_encoder->audio->write_sad_regs(encoder, sads, sad_c$ kfree(sads); } in theses files drivers/gpu/drm/radeon/radeon_audio.c drivers/gpu/drm/amd/amdgpu/dce_v6_0.c drivers/gpu/drm/amd/amdgpu/dce_v10_0.c drivers/gpu/drm/amd/amdgpu/dce_v11_0.c drivers/gpu/drm/amd/amdgpu/dce_v8_0.c which ``drm_edid_to_sad‘’ is defined in drivers/gpu/drm/drm_edid.c. Comments read /** * drm_edid_to_sad - extracts SADs from EDID * @edid: EDID to parse * @sads: pointer that will be set to the extracted SADs * * Looks for CEA EDID block and extracts SADs (Short Audio Descriptors) fr$ * * Note: The returned pointer needs to be freed using kfree(). * * Return: The number of found SADs or negative number on error. */ Considering the term ``EDID'' and some audio related words, I think it's reading some info from your monitor. -- Silence is golden.
[gentoo-user] DRM error: couldn't read SADs
Hello list, My VGA card is: # lspci | grep VGA 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere [Radeon Pro WX 5100] I've been getting these entries in dmesg every time I boot the machine, ever since I installed the card some months ago: [drm:dce_v11_0_afmt_setmode] *ERROR* Couldn't read SADs: 0 [...] traps: plugin-containe[6833] general protection ip:7f0a2e1711b1 sp:7fff6f64dc30 error:0 in ld-2.25.so[7f0a2e15c000+23000] What is a SAD (other than a seasonal affective disorder)? That library comes from glibc, of which I've had 5 versions or revisions in that time The error seems not to be doing any harm, but it'd be good to clear it up. Google hasn't helped me. Can anyone offer me a hint? -- Regards, Peter.