Re: More questions and patches for 835GM/ns2501 DVO

[Daniel Vetter <daniel@ffwll.ch>]

On Sun, Nov 03, 2013 at 10:18:14PM +0100, Daniel Vetter wrote:
> 
> On Sun, Nov 3, 2013 at 8:00 PM, Thomas Richter <thor@math.tu-berlin.de> wrote:
> > On 03.11.2013 18:13, Daniel Vetter wrote:
> >>>
> >>> Have you tried my patch to reorder the dvo sequence a bit? That /should/
> >>> get all these things right:
> >>>
> >>> http://www.spinics.net/lists/intel-gfx/msg34349.html
> >>
> >> There's also a follow-up patch for you to test:
> >>
> >>
> >> http://www.spinics.net/lists/intel-gfx/msg34350.html
> >>
> >> That would prove that the first patch does indeed work. Note that patch 1
> >> in this series is already merged.
> >
> > Thanks, I tried. Actually, this worked fairly (but not perfectly) well. I no
> > longer get a "stuck DVO" as I did before, i.e. the "re-enable" logic is not
> > triggered anymore. However, I do get (occasionally) a kernel-oops:
> 
> That's just a warning, not an oops ...
> 
> >
> > ------------[ cut here ]------------
> > WARNING: CPU: 0 PID: 2311 at drivers/gpu/drm/i915/intel_display.c:1098
> > assert_cursor.constprop.68+0xba/0xc0 [i915]()
> > cursor on pipe A assertion failure (expected off, current on)
> > Modules linked in: cpufreq_stats binfmt_misc michael_mic arc4 ecb
> > lib80211_crypt_tkip lib80211_crypt_ccmp fuse nfsd exportfs nfs_acl nfs lockd
> > fscache sunrpc loop firewire_sbp2 hostap_cs hostap snd_intel8x0
> > snd_ac97_codec ac97_bus lib80211 snd_pcm i915 snd_page_alloc snd_seq
> > snd_seq_device snd_timer psmouse snd pcmcia apanel input_polldev soundcore
> > yenta_socket pcmcia_rsrc pcmcia_core lpc_ich i2c_i801 mfd_core pcspkr
> > i2c_algo_bit rng_core serio_raw evdev drm_kms_helper drm fujitsu_laptop
> > led_class intel_agp intel_gtt agpgart i2c_core video ac button hid_generic
> > usbhid hid sg sr_mod cdrom firewire_ohci firewire_core crc_itu_t 8139too
> > 8139cp mii uhci_hcd usbcore usb_common
> > CPU: 0 PID: 2311 Comm: Xorg Tainted: G        W    3.12.0-rc7+ #13
> > Hardware name: FUJITSU SIEMENS LIFEBOOK S Series/FJNB159, BIOS Version 1.06
> > 07/02/2002
> >  c12f8c44 c1033def f8ad3990 f6adfab0 00000907 f8ad25d8 0000044a f8a81ffa
> >  f8a81ffa f5ca8000 00000041 00000000 f5ca8000 c1033eb3 00000009 f6adfa98
> >  f8ad3990 f6adfab0 f8a81ffa f8ad25d8 0000044a f8ad3990 00000041 f8adb9a0
> > Call Trace:
> >  [<c12f8c44>] ? dump_stack+0xa/0x13
> >  [<c1033def>] ? warn_slowpath_common+0x7f/0xb0
> >  [<f8a81ffa>] ? assert_cursor.constprop.68+0xba/0xc0 [i915]
> >  [<f8a81ffa>] ? assert_cursor.constprop.68+0xba/0xc0 [i915]
> >  [<c1033eb3>] ? warn_slowpath_fmt+0x33/0x40
> >  [<f8a81ffa>] ? assert_cursor.constprop.68+0xba/0xc0 [i915]
> >  [<f8a83b90>] ? intel_disable_pipe+0x30/0xb0 [i915]
> >  [<f8a8491a>] ? i9xx_crtc_disable+0xca/0x2f0 [i915]
> >  [<f8a8b25e>] ? __intel_set_mode+0x7ae/0x13b0 [i915]
> >  [<f8a8e1f3>] ? intel_set_mode+0x23/0x40 [i915]
> >  [<f8a8e9bc>] ? intel_crtc_set_config+0x7ac/0x9d0 [i915]
> >  [<f802fe33>] ? drm_mode_set_config_internal+0x43/0xb0 [drm]
> >  [<f81386a5>] ? drm_fb_helper_set_par+0x45/0xac [drm_kms_helper]
> >  [<c11a7976>] ? fb_set_var+0x1a6/0x420
> >  [<c10eec6e>] ? __find_get_block+0x9e/0x160
> >  [<c11b56e0>] ? fbcon_blank+0x290/0x2d0
> >  [<c1203848>] ? do_unblank_screen+0x98/0x1b0
> >  [<c1201acd>] ? notify_update+0x1d/0x30
> >  [<c11faa12>] ? complete_change_console+0x52/0xe0
> >  [<c11fbba4>] ? vt_ioctl+0x1104/0x1220
> >  [<f802a1d0>] ? drm_setmaster_ioctl+0xe0/0xe0 [drm]
> >  [<c11faaa0>] ? complete_change_console+0xe0/0xe0
> >  [<c11f17da>] ? tty_ioctl+0x21a/0x9a0
> >  [<c10adb12>] ? do_wp_page.isra.92+0x2a2/0x650
> >  [<c10af428>] ? handle_mm_fault+0x318/0x610
> >  [<c11f15c0>] ? no_tty+0x20/0x20
> >  [<c10d66ac>] ? do_vfs_ioctl+0x7c/0x550
> >  [<c102d221>] ? __do_page_fault+0x1b1/0x490
> >  [<c10c7d17>] ? vfs_write+0x137/0x1b0
> >  [<c10d6bc6>] ? SyS_ioctl+0x46/0x80
> >  [<c12fc19e>] ? sysenter_do_call+0x12/0x26
> > ---[ end trace 85d231d1072e932a ]---
> >
> > If this happens, I get a black screen with only a cursor on it. Switching to
> > the console and back restores the screen.
> 
> Hm, that would mean that the cursor is somehow stuck in the enabled state,
> despite that we've tried to disabled it very hard. Can you please try out
> the below patch? If this doesn't work please take not of the different
> WARNINGs you're hitting and whether it's always the same one with the same
> calltrace or something different.
> 
> I think for now we should try to get the single monitor case working - I
> have a few theories for the dual-screen issues, but there's not much point
> working on them if the simple case doesn't work yet.
> 
> Also I think I'll merge the two patches if they don't make things worse
> for you, imo it's the right approach and at least conceptually should be
> able to avoid all these retry loops.
> 
> Thanks, Daniel
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index f34252d134b6..04d2699f51b4 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -7123,7 +7123,9 @@ static void i9xx_update_cursor(struct drm_crtc *crtc, u32 base)
>  		intel_crtc->cursor_visible = visible;
>  	}
>  	/* and commit changes on next vblank */
> +	POSTING_READ(CURCNTR(pipe));
>  	I915_WRITE(CURBASE(pipe), base);
> +	POSTING_READ(CURBASE(pipe));
>  }
>  
>  static void ivb_update_cursor(struct drm_crtc *crtc, u32 base)
> @@ -7152,7 +7154,9 @@ static void ivb_update_cursor(struct drm_crtc *crtc, u32 base)
>  		intel_crtc->cursor_visible = visible;
>  	}
>  	/* and commit changes on next vblank */
> +	POSTING_READ(CURCNTR_IVB(pipe));
>  	I915_WRITE(CURBASE_IVB(pipe), base);
> +	POSTING_READ(CURBASE_IVB(pipe));
>  }

To clarify: Do you need this patch to make the single-pipe mode work
reliably? It's a bit unclear in your answer ...

Thanks, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch