On 11/14/2016 10:15 PM, Ville Syrjälä wrote: > On Mon, Nov 14, 2016 at 10:12:04PM +0530, Sharma, Shashank wrote: >> Regards >> >> Shashank >> >> >> On 11/14/2016 9:50 PM, Ville Syrjälä wrote: >>> On Mon, Nov 14, 2016 at 09:37:18PM +0530, Sharma, Shashank wrote: >>>> Regards >>>> >>>> Shashank >>>> >>>> >>>> On 11/14/2016 9:19 PM, Ville Syrjälä wrote: >>>>> On Mon, Nov 14, 2016 at 08:14:34PM +0530, Sharma, Shashank wrote: >>>>>> Regards >>>>>> Shashank >>>>>>> the revert: >>>>>>> >>>>>>> HDMI2 connected 1920x1080+0+0 (normal left inverted right x axis y >>>>>>> axis) 700mm x 390mm >>>>>>> - 1920x1080 60.00*+ >>>>>>> - 1920x1080i 60.00 50.00 >>>>>>> + 1920x1080 60.00*+ 50.00 59.94 30.00 25.00 24.00 >>>>>>> 29.97 23.98 >>>>>>> + 1920x1080i 60.00 50.00 59.94 >>>>>>> 1600x1200 60.00 >>>>>>> 1680x1050 59.88 >>>>>>> 1280x1024 75.02 60.02 >>>>>>> @@ -13,30 +13,29 @@ >>>>>>> 1360x768 60.02 >>>>>>> 1280x800 59.91 >>>>>>> 1152x864 75.00 >>>>>>> - 1280x720 60.00 50.00 >>>>>>> + 1280x720 60.00 50.00 59.94 >>>>>>> 1024x768 75.03 70.07 60.00 >>>>>>> 832x624 74.55 >>>>>>> 800x600 72.19 75.00 60.32 >>>>>>> - 640x480 75.00 72.81 66.67 59.94 >>>>>>> + 720x576 50.00 >>>>>>> + 720x480 60.00 59.94 >>>>>>> + 640x480 75.00 72.81 66.67 60.00 59.94 >>>>>>> 720x400 70.08 >>>>>> None of these aspect ratios are new modes / new aspect ratios from HDMI >>>>>> 2.0/CEA-861-F >>>>>> These are the existing modes, and should be independent of reverted >>>>>> patches. >>>>> They're affected because your patches changed them by adding the aspect >>>>> ratio flags to them. >>>> Yes, But they are independent of reverted patch, which adds aspect ratio >>>> for HDMI 2.0 ratios (64:27 and 256:135) >>> The second patch had to be reverted so that the first patch would revert >>> cleanly. >>> >>>>>>> This was with sna, which does this: >>>>>>> #define KNOWN_MODE_FLAGS ((1<<14)-1) >>>>>>> if (mode->status == MODE_OK && kmode->flags & ~KNOWN_MODE_FLAGS) >>>>>>> mode->status = MODE_BAD; /* unknown flags => unhandled */ >>>>>>> so all the modes with an aspect ratio just vanished. >>>>>>> >>>>>>> -modesetting and -ati on the other hand just copy over the unknown >>>>>>> bits into the xrandr mode structure, which sounds dubious at best: >>>>>>> mode->Flags = kmode->flags; //& FLAG_BITS; >>>>>>> I've not checked what damage it can actually cause. >>>>>>> >>>>>>> >>>>>>> It looks like a few modes disappeared from the kernel's mode list >>>>>>> as well, presumably because some cea modes in the list originated from >>>>>>> DTDs and whanot so they don't have an aspect ratio and that causes >>>>>>> add_alternate_cea_modes() to ignore them. So not populating an aspect >>>>>>> ratio for cea modes originating from a source other than >>>>>>> edid_cea_modes[] looks like another bug to me as well. >>>>>> I am writing a patch series to cap the aspect ratio implementation under >>>>>> a drm_cap_hdmi2_aspect_ratios >>>>>> This is how its going to work (inspired from the 2D/stereo series from >>>>>> damien L) >>>>>> >>>>>> - Add a new capability hdmi2_ar >>>>> It should be just a generic "expose aspect ratio flags to userspace?" >>>> Makes sense, in this way we can even revert the aspect_ratio property >>>> for HDMI connector, as discussed during >>>> the code review sessions of this patch series. In this way, when kernel >>>> will expose the aspect ratios, it will either >>>> do the aspect ratios as per EDID, or wont. >>>>>> - by default parsing the new hdmi 2.0 aspect ratio will be disabled >>>>>> under check of this cap >>>>>> - during bootup time, while initializing the display, a userspace can >>>>>> get_cap on the hdmi2_aspect_ratio >>>>>> - If it wants HDMI 2.0 aspect ratio support, it will set the cap, and >>>>>> kernel will expose these aspect ratios >>>>>>> Another bug I think might be the ordering of the modes with aspect ratio >>>>>>> specified. IIRC the spec says that the preferred aspect ratio should be >>>>>>> listed first in the EDID, but I don't think we preserve that ordering >>>>>>> in the final mode list. I guess we could fix that by somehow noting >>>>>>> which aspect ratio is preferred and sort based on that, or we try to >>>>>>> preserve the order from the EDID until we're ready to sort, and then do >>>>>>> the sorting with a stable algorithm. >>>>>> AFAIK The mode order and priority is decided and arranged in userspace, >>>>>> based on various factors like >>>>>> - preferred mode. >>>>>> - previously applied mode in previous sessions (like for android tvs) >>>>>> - Bigger h/w vs better refresh rate ? >>>>>> - Xserver applies its own algorithms to decide which mode should be >>>>>> shown first. >>>>> Xorg does sort on its own. But since it doesn't know anything about >>>>> aspect ratios and whatnot I wouldn't rely on that for anything. I >>>>> also wouldn't expect eg. wayland compositors to do their own sorting. >>>>> And yeah, looks like weston at least doesn't do any sorting whatsoever. >>>>> >>>>>> I dont think kernel needs to bother about it. >>>>> So I'm going to say that we in fact do need to bother. >>>>> >>>> IMHO, making policies for UI is not a part of kernel design, a UI >>>> manager (Hardware composed, X or Wayland) should take care of it, as >>>> they have access to much information (Like previously applied mode, user >>>> preference etc). When it comes to sorting of modes, the only general rule >>>> across drivers like FB, V4L2, I have seen is the first mode in the list >>>> should be preferred mode, which we are still keeping. And after that our >>>> probed_modes were >>>> anyways not sorted now, so it doesn't matter further. >>> Having userspace be responsible for sorting the aspect ratios would >>> perhaps require that userspace parses the EDID, which is pretty crazy. >> Why ? >> userspace has to just set cap for aspect ratio, and kernel can read >> EDID, parse the CEA block, populate the aspect ratios flags >> and add the modes (Just what this patch was doing, except the cap part) >> Once userspace has the getResources/getConnector call filled, it can >> access all the modes (with and without aspect) and do the sorting >> in any way it wants. >>> I guess it could try to deduce something from the physical aspect ratio >>> of the display, but I'm not sure that's quite what we want either. >>> >>> Also we already sort the modes in the kernel anyway, so it's not like >>> we'd be doing something new by also considering the aspect ratios. >>> I would at the very least want to avoid a totally random order between >>> modes that differ only by the aspect ratio. >> Path: get_connector -> probe_single_connector_mode -> drm_add_edid_modes >> Again, IMHO, we don't sort the modes in kernel, we populate modes in a >> particular order, which is: >> (From drm_edid.c::drm_add_edid_modes) >> ############################################################## >> /* >> * EDID spec says modes should be preferred in this order: >> * - preferred detailed mode >> * - other detailed modes from base block >> * - detailed modes from extension blocks >> * - CVT 3-byte code modes >> * - standard timing codes >> * - established timing codes >> * - modes inferred from GTF or CVT range information >> * >> * We get this pretty much right. >> * >> * XXX order for additional mode types in extension blocks? >> */ >> num_modes += add_detailed_modes(connector, edid, quirks); >> num_modes += add_cvt_modes(connector, edid); >> num_modes += add_standard_modes(connector, edid); >> num_modes += add_established_modes(connector, edid); >> num_modes += add_cea_modes(connector, edid); >> num_modes += add_alternate_cea_modes(connector, edid); >> num_modes += add_displayid_detailed_modes(connector, edid); >> ############################################################### >> >> Here the modes are added in the connector, in the same order they are >> arranged into their respective blocks in EDID. >> But the order to read the block is a preferred order (no sorting). >> >> Now, in this patch series, we are adding aspect ratio information in >> edid_cea_modes db, which is going to affect only >> add_cea/alternate_cea_modes() call, and the modes accordingly. >> Please let me know if I misunderstood something here. > We explicitly sort the modes after this. >
In any case, I guess addition of a cap for aspect ratio should fix the current objections for this implementation. And I will keep it 0 by default, so that no aspect ratio information is added until userspace sets the cap to 1 on its own. Regards Shashank >> Regards >> Shashank >>>> If X server doesn't know what to do with aspect ratio flags, it can >>>> chose not to set the cap, and if HWC knows, it can chose to set. This is >>>> the same situation as 2D stereo modes >>>> which are existing already. >>>> >>>> Regards >>>> Shashank
