[BUG] drm_rockchip: rk3066_hdmi: No driver support for vblank timestamp query.

Tue Nov 27 09:12:13 UTC 2018

On Tue, Nov 27, 2018 at 6:11 PM Tomasz Figa <tfiga at chromium.org> wrote:
>
> Hi Johan,
>
> Adding the dri-devel mailing lists and some maintainers.
>
> On Sun, Nov 25, 2018 at 12:53 AM Johan Jonker <jbx9999 at hotmail.com> wrote:
> >
> > For a TV stick called MK808 with rk3066 processor I would like to enable
> > the VOP and HDMI.
> > With boot logo and console enabled I can see 2 pinguins and a cursor for
> > a second and then the display is black.
> > From a internet search I learned that the rk3066 doesn't support a
> > vblank counter.
> > Yet they have replaced the Rockchip custom wait_for_vblanks with a drm
> > helper.
>
> All of the Rockchip SoCs supported by the upstream driver lack a
> vblank counter and the code that you refer to is designed for this
> limitation in particular. I suspect the problem you're seeing is
> unrelated.
>
> >
> > Question for the authors and reviewers:
> >
> > -Did anyone test this convert on a rk3066?
>
> Not sure. I have tested internally on RK3399.
>
> > -Can someone with more knowledge explane what happens in this crash
> > rapport below.
>
> To me, it looks like the vblank interrupt
>

Oops. I meant:

It looks like the vblank interrupt doesn't fire for some reason.

> > -Can this be fixed?
> >
>
> Very likely. :)
>
> > Please contact if more info is needed.
> >
>
> I don't see display support enabled in the rk3066-mk808.dts in latest upstream:
> https://elixir.bootlin.com/linux/latest/source/arch/arm/boot/dts/rk3066a-mk808.dts
>
> Do you have any local changes in your kernel sources?
>
> Best regards,
> Tomasz
>
> > Kind regards,
> >
> > Johan Jonker
> >
> > ///////////////////////////////////////////
> >
> > Reference:
> >
> > -drm/rockchip: Replace custom wait_for_vblanks with helper
> > https://patchwork.kernel.org/patch/9331351/
> >
> > -drm/rockchip: don't wait for vblank if fb hasn't changed
> > https://patchwork.kernel.org/patch/8024741/
> >
> > -explain why we can't wait_for_vblanks
> > https://lore.kernel.org/patchwork/patch/635586/
> >
> > -drm/rockchip: Convert to support atomic API
> > https://patchwork.kernel.org/patch/7732341/
> >
> > -drm/rockchip: Convert to support atomic API
> > https://patchwork.kernel.org/patch/7868601/
> >
> > https://lkml.org/lkml/2017/9/4/251
> >
> >
> > //////////////////////////////////////////
> >
> > [    0.897682] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
> > [    0.904616] [drm] No driver support for vblank timestamp query.
> >
> > [    1.440201] [drm:drm_calc_timestamping_constants] crtc 30: hwmode:
> > htotal 1650, vtotal 750, vdisplay 720
> > [    1.440212] [drm:drm_calc_timestamping_constants] crtc 30: clock
> > 74250 kHz framedur 16666666 linedur 22222
> >
> > [    1.440307] [drm:drm_crtc_vblank_on] crtc 0, vblank enabled 0,
> > inmodeset 0
> >
> > [    1.451189] [drm:drm_vblank_enable] enabling vblank on crtc 0, ret: 0
> >
> > [    1.451202] [drm:drm_update_vblank_count] updating vblank count on
> > crtc 0: current=1, diff=0, hw=0 hw_last=0
> > .
> > .
> > .
> > .
> > [    4.303883] [drm:drm_update_vblank_count] updating vblank count on
> > crtc 0: current=113, diff=1, hw=0 hw_last=0
> > [    4.304140] Warning: unable to open an initial console.
> >
> >
> > [    6.777825] ------------[ cut here ]------------
> > [    6.786554] WARNING: CPU: 0 PID: 19 at
> > drivers/gpu/drm/drm_atomic_helper.c:1406
> > drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0
> > [    6.800803] [CRTC:30:crtc-0] vblank wait timed out
> > [    6.806701] Modules linked in:
> > [    6.810317] CPU: 0 PID: 19 Comm: kworker/0:1 Not tainted
> > 4.20.0-rc1-g0d694f0b3-dirty #19
> > [    6.819938] Hardware name: Rockchip (Device Tree)
> > [    6.825498] Workqueue: events output_poll_execute
> > [    6.831062] [<c01104a0>] (unwind_backtrace) from [<c010c868>]
> > (show_stack+0x10/0x14)
> > [    6.840191] [<c010c868>] (show_stack) from [<c069e538>]
> > (dump_stack+0x88/0x9c)
> > [    6.848729] [<c069e538>] (dump_stack) from [<c0122784>]
> > (__warn+0xf8/0x110)
> > [    6.856936] [<c0122784>] (__warn) from [<c01227e4>]
> > (warn_slowpath_fmt+0x48/0x6c)
> > [    6.873544] [<c01227e4>] (warn_slowpath_fmt) from [<c0445b04>]
> > (drm_atomic_helper_wait_for_vblanks.part.1+0x298/0x2a0)
> > [    6.886148] [<c0445b04>] (drm_atomic_helper_wait_for_vblanks.part.1)
> > from [<c0477fec>] (rockchip_atomic_helper_commit_tail_rpm+0x17c/0x194)
> > [    6.900896] [<c0477fec>] (rockchip_atomic_helper_commit_tail_rpm)
> > from [<c0447418>] (commit_tail+0x40/0x6c)
> > [    6.912370] [<c0447418>] (commit_tail) from [<c0447508>]
> > (drm_atomic_helper_commit+0xbc/0x128)
> > [    6.922515] [<c0447508>] (drm_atomic_helper_commit) from [<c0449b38>]
> > (restore_fbdev_mode_atomic+0x1cc/0x1dc)
> > [    6.934196] [<c0449b38>] (restore_fbdev_mode_atomic) from
> > [<c044d34c>] (drm_fb_helper_restore_fbdev_mode_unlocked+0x54/0xa0)
> > [    6.947410] [<c044d34c>] (drm_fb_helper_restore_fbdev_mode_unlocked)
> > from [<c044d3c8>] (drm_fb_helper_set_par+0x30/0x54)
> > [    6.960213] [<c044d3c8>] (drm_fb_helper_set_par) from [<c044d2b4>]
> > (drm_fb_helper_hotplug_event.part.9+0x90/0xa8)
> > [    6.972305] [<c044d2b4>] (drm_fb_helper_hotplug_event.part.9) from
> > [<c043cd70>] (drm_kms_helper_hotplug_event+0x24/0x30)
> > [    6.985108] [<c043cd70>] (drm_kms_helper_hotplug_event) from
> > [<c043cf30>] (output_poll_execute+0x188/0x1a0)
> > [    6.996583] [<c043cf30>] (output_poll_execute) from [<c013bc68>]
> > (process_one_work+0x218/0x508)
> > [    7.006829] [<c013bc68>] (process_one_work) from [<c013ca9c>]
> > (worker_thread+0x30/0x59c)
> > [    7.016360] [<c013ca9c>] (worker_thread) from [<c01415b0>]
> > (kthread+0x124/0x154)
> > [    7.025073] [<c01415b0>] (kthread) from [<c01010e8>]
> > (ret_from_fork+0x14/0x2c)
> > [    7.033567] Exception stack(0xeea3dfb0 to 0xeea3dff8)
> > [    7.039514] dfa0:                                     00000000
> > 00000000 00000000 00000000
> > [    7.049145] dfc0: 00000000 00000000 00000000 00000000 00000000
> > 00000000 00000000 00000000
> > [    7.058774] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
> > [    7.066677] ---[ end trace aaf7d2040cebe21e ]---
> >