[PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Manasi Navare]

The detect_done flag was introduced in the commit
7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid
multiple detects on hotplug where intel_dp_long_pulse()
was called from HPD handler as well as in intel_dp_detect.
So this detect_done flag was required to make sure intel_dp_detect()
did not call long pulse handler again if it was already been called
from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb
differs the long hpd handling entirely until the hotplug work runs to
avoid the double long hpd handling the "detect_done" flag is trying
to prevent.

So now we do not need to reset the detect_done flag to false in
intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
that intel_dp_detect does a full detect. However if the .detect
gets called during mode enumeration then we do not need to do a
full detect. This patch avoids the WARNS_ONS during connected boot
case when it calls intel_dp_check_link_status() due to multiple
detects and also avoids DP compliance failures. It avoids doing
a full detect every single time on .detect().

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
---
 drivers/gpu/drm/i915/intel_dp.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index db75bb9..9c9277e 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
 	if (!intel_dp->detect_done)
 		status = intel_dp_long_pulse(intel_dp->attached_connector);
 
-	intel_dp->detect_done = false;
-
 	return status;
 }
 
-- 
1.9.1

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

✓ Fi.CI.BAT: success for drm/i915: Do not reset detect_done flag in intel_dp_detect

[Patchwork]

== Series Details ==

Series: drm/i915: Do not reset detect_done flag in intel_dp_detect
URL   : https://patchwork.freedesktop.org/series/16456/
State : success

== Summary ==

Series 16456v1 drm/i915: Do not reset detect_done flag in intel_dp_detect
https://patchwork.freedesktop.org/api/1.0/series/16456/revisions/1/mbox/


fi-bdw-5557u     total:247  pass:218  dwarn:0   dfail:0   fail:0   skip:29 
fi-bsw-n3050     total:247  pass:194  dwarn:0   dfail:0   fail:0   skip:53 
fi-bxt-t5700     total:247  pass:205  dwarn:0   dfail:0   fail:0   skip:42 
fi-byt-j1900     total:247  pass:205  dwarn:0   dfail:0   fail:0   skip:42 
fi-byt-n2820     total:247  pass:201  dwarn:0   dfail:0   fail:0   skip:46 
fi-hsw-4770      total:247  pass:213  dwarn:0   dfail:0   fail:0   skip:34 
fi-hsw-4770r     total:247  pass:213  dwarn:0   dfail:0   fail:0   skip:34 
fi-ilk-650       total:247  pass:180  dwarn:0   dfail:0   fail:0   skip:67 
fi-ivb-3520m     total:247  pass:212  dwarn:0   dfail:0   fail:0   skip:35 
fi-ivb-3770      total:247  pass:211  dwarn:0   dfail:0   fail:0   skip:36 
fi-kbl-7500u     total:247  pass:211  dwarn:0   dfail:0   fail:0   skip:36 
fi-skl-6260u     total:247  pass:219  dwarn:0   dfail:0   fail:0   skip:28 
fi-skl-6700hq    total:247  pass:213  dwarn:0   dfail:0   fail:0   skip:34 
fi-skl-6700k     total:247  pass:209  dwarn:3   dfail:0   fail:0   skip:35 
fi-skl-6770hq    total:247  pass:219  dwarn:0   dfail:0   fail:0   skip:28 
fi-snb-2520m     total:247  pass:201  dwarn:0   dfail:0   fail:0   skip:46 
fi-snb-2600      total:247  pass:200  dwarn:0   dfail:0   fail:0   skip:47 

08aa3ac5c18159c9105252903713cb21c27e9442 drm-tip: 2016y-12m-06d-18h-32m-52s UTC integration manifest
9e30950 drm/i915: Do not reset detect_done flag in intel_dp_detect

== Logs ==

For more details see: https://intel-gfx-ci.01.org/CI/Patchwork_3210/
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Jani Nikula]

On Wed, 07 Dec 2016, Manasi Navare <manasi.d.navare@intel.com> wrote:
> The detect_done flag was introduced in the commit
> 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid

The preferred format to cite commits is:

7d23e3c37bb3 ("drm/i915: Cleaning up intel_dp_hpd_pulse")

or

commit 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c
Author: Shubhangi Shrivastava <shubhangi.shrivastava@intel.com>
Date:   Wed Mar 30 18:05:23 2016 +0530

    drm/i915: Cleaning up intel_dp_hpd_pulse


> multiple detects on hotplug where intel_dp_long_pulse()
> was called from HPD handler as well as in intel_dp_detect.
> So this detect_done flag was required to make sure intel_dp_detect()
> did not call long pulse handler again if it was already been called
> from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb

1015811609c0 ("drm/i915: Move long hpd handling into the hotplug work")

> differs the long hpd handling entirely until the hotplug work runs to
> avoid the double long hpd handling the "detect_done" flag is trying
> to prevent.
>
> So now we do not need to reset the detect_done flag to false in
> intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
> that intel_dp_detect does a full detect. However if the .detect
> gets called during mode enumeration then we do not need to do a
> full detect. This patch avoids the WARNS_ONS during connected boot

Please include such a backtrace in the commit message; it makes matching
bugs and fixes so much easier.

IIUC the warnings were introduced by 1015811609c0 ("drm/i915: Move long
hpd handling into the hotplug work"), and that's cc: stable, so this one
should be too, along with

Fixes: 1015811609c0 ("drm/i915: Move long hpd handling into the hotplug work")
Cc: stable@vger.kernel.org

Of course, someone(tm) will still need to make sure this is the right
fix...


BR,
Jani.


> case when it calls intel_dp_check_link_status() due to multiple
> detects and also avoids DP compliance failures. It avoids doing
> a full detect every single time on .detect().
>
> Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index db75bb9..9c9277e 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
>  	if (!intel_dp->detect_done)
>  		status = intel_dp_long_pulse(intel_dp->attached_connector);
>  
> -	intel_dp->detect_done = false;
> -
>  	return status;
>  }

-- 
Jani Nikula, Intel Open Source Technology Center
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Ville Syrjälä]

On Tue, Dec 06, 2016 at 04:43:51PM -0800, Manasi Navare wrote:
> The detect_done flag was introduced in the commit
> 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid
> multiple detects on hotplug where intel_dp_long_pulse()
> was called from HPD handler as well as in intel_dp_detect.
> So this detect_done flag was required to make sure intel_dp_detect()
> did not call long pulse handler again if it was already been called
> from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb
> differs the long hpd handling entirely until the hotplug work runs to
> avoid the double long hpd handling the "detect_done" flag is trying
> to prevent.

That sentence doesn't parse here. Anyways, the flag indeed is now a nop
and your patch is pretty much the same what I did here:
https://patchwork.freedesktop.org/patch/101476/

> 
> So now we do not need to reset the detect_done flag to false in
> intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
> that intel_dp_detect does a full detect. However if the .detect
> gets called during mode enumeration then we do not need to do a
> full detect. This patch avoids the WARNS_ONS during connected boot
> case when it calls intel_dp_check_link_status() due to multiple
> detects

How exactly does it do that? Also we shouldn't sweep that under the rug
anyway. Instead someone should actually fix the problem that causes the
WARN.

> and also avoids DP compliance failures. It avoids doing
> a full detect every single time on .detect().
> 
> Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index db75bb9..9c9277e 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
>  	if (!intel_dp->detect_done)
>  		status = intel_dp_long_pulse(intel_dp->attached_connector);
>  
> -	intel_dp->detect_done = false;
> -
>  	return status;
>  }
>  
> -- 
> 1.9.1

-- 
Ville Syrjälä
Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Manasi Navare]

On Wed, Dec 07, 2016 at 04:05:56PM +0200, Ville Syrjälä wrote:
> On Tue, Dec 06, 2016 at 04:43:51PM -0800, Manasi Navare wrote:
> > The detect_done flag was introduced in the commit
> > 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid
> > multiple detects on hotplug where intel_dp_long_pulse()
> > was called from HPD handler as well as in intel_dp_detect.
> > So this detect_done flag was required to make sure intel_dp_detect()
> > did not call long pulse handler again if it was already been called
> > from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb
> > differs the long hpd handling entirely until the hotplug work runs to
> > avoid the double long hpd handling the "detect_done" flag is trying
> > to prevent.
> 
> That sentence doesn't parse here. Anyways, the flag indeed is now a nop
> and your patch is pretty much the same what I did here:
> https://patchwork.freedesktop.org/patch/101476/
>

I looked at this patch and yes it is the same thing except that it keeps
the name of the flag unchanged plus previous patch is too old and wont
apply cleanly unless you rebase it. I will add the reseting of this flag in the
resume case. 
Thoughts?

> > 
> > So now we do not need to reset the detect_done flag to false in
> > intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
> > that intel_dp_detect does a full detect. However if the .detect
> > gets called during mode enumeration then we do not need to do a
> > full detect. This patch avoids the WARNS_ONS during connected boot
> > case when it calls intel_dp_check_link_status() due to multiple
> > detects
> 
> How exactly does it do that? Also we shouldn't sweep that under the rug
> anyway. Instead someone should actually fix the problem that causes the
> WARN.
>

Actually an additional call to intel_dp_long_pulse from intel_dp_detect()
because we are not resetting the detect_done flag, makes the function
call intel_dp_check_link_status() in the case when intel_dp->lane_count is 
0 and throws the WARN about that. So by resetting the flag we avoid this
unwanted call to intel_dp_long_pulse and that gets rid of the warning.

Manasi
 
> > and also avoids DP compliance failures. It avoids doing
> > a full detect every single time on .detect().
> > 
> > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_dp.c | 2 --
> >  1 file changed, 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> > index db75bb9..9c9277e 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
> >  	if (!intel_dp->detect_done)
> >  		status = intel_dp_long_pulse(intel_dp->attached_connector);
> >  
> > -	intel_dp->detect_done = false;
> > -
> >  	return status;
> >  }
> >  
> > -- 
> > 1.9.1
> 
> -- 
> Ville Syrjälä
> Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Manasi Navare]

Ville,
You mentioned that this detect_done should be set to false also
in the resume case so in i915_display_resume where it calls
intel_hpd_init that eventually schedules the hpd_poll_init_work and
calls drm_helper_hpd_irq_event() which then calls .detect().
So in this case if I have to reset this detect_done in the
hpd_poll_init_work, how do I make sure I do it only if the
connector is DP?

Manasi 

On Wed, Dec 07, 2016 at 04:05:56PM +0200, Ville Syrjälä wrote:
> On Tue, Dec 06, 2016 at 04:43:51PM -0800, Manasi Navare wrote:
> > The detect_done flag was introduced in the commit
> > 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid
> > multiple detects on hotplug where intel_dp_long_pulse()
> > was called from HPD handler as well as in intel_dp_detect.
> > So this detect_done flag was required to make sure intel_dp_detect()
> > did not call long pulse handler again if it was already been called
> > from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb
> > differs the long hpd handling entirely until the hotplug work runs to
> > avoid the double long hpd handling the "detect_done" flag is trying
> > to prevent.
> 
> That sentence doesn't parse here. Anyways, the flag indeed is now a nop
> and your patch is pretty much the same what I did here:
> https://patchwork.freedesktop.org/patch/101476/
> 
> > 
> > So now we do not need to reset the detect_done flag to false in
> > intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
> > that intel_dp_detect does a full detect. However if the .detect
> > gets called during mode enumeration then we do not need to do a
> > full detect. This patch avoids the WARNS_ONS during connected boot
> > case when it calls intel_dp_check_link_status() due to multiple
> > detects
> 
> How exactly does it do that? Also we shouldn't sweep that under the rug
> anyway. Instead someone should actually fix the problem that causes the
> WARN.
> 
> > and also avoids DP compliance failures. It avoids doing
> > a full detect every single time on .detect().
> > 
> > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_dp.c | 2 --
> >  1 file changed, 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> > index db75bb9..9c9277e 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
> >  	if (!intel_dp->detect_done)
> >  		status = intel_dp_long_pulse(intel_dp->attached_connector);
> >  
> > -	intel_dp->detect_done = false;
> > -
> >  	return status;
> >  }
> >  
> > -- 
> > 1.9.1
> 
> -- 
> Ville Syrjälä
> Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Ville Syrjälä]

On Wed, Dec 07, 2016 at 07:51:21PM -0800, Manasi Navare wrote:
> Ville,
> You mentioned that this detect_done should be set to false also
> in the resume case so in i915_display_resume where it calls
> intel_hpd_init that eventually schedules the hpd_poll_init_work and
> calls drm_helper_hpd_irq_event() which then calls .detect().
> So in this case if I have to reset this detect_done in the
> hpd_poll_init_work, how do I make sure I do it only if the
> connector is DP?

We have the .reset hook for these sort of things.

> 
> Manasi 
> 
> On Wed, Dec 07, 2016 at 04:05:56PM +0200, Ville Syrjälä wrote:
> > On Tue, Dec 06, 2016 at 04:43:51PM -0800, Manasi Navare wrote:
> > > The detect_done flag was introduced in the commit
> > > 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid
> > > multiple detects on hotplug where intel_dp_long_pulse()
> > > was called from HPD handler as well as in intel_dp_detect.
> > > So this detect_done flag was required to make sure intel_dp_detect()
> > > did not call long pulse handler again if it was already been called
> > > from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb
> > > differs the long hpd handling entirely until the hotplug work runs to
> > > avoid the double long hpd handling the "detect_done" flag is trying
> > > to prevent.
> > 
> > That sentence doesn't parse here. Anyways, the flag indeed is now a nop
> > and your patch is pretty much the same what I did here:
> > https://patchwork.freedesktop.org/patch/101476/
> > 
> > > 
> > > So now we do not need to reset the detect_done flag to false in
> > > intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
> > > that intel_dp_detect does a full detect. However if the .detect
> > > gets called during mode enumeration then we do not need to do a
> > > full detect. This patch avoids the WARNS_ONS during connected boot
> > > case when it calls intel_dp_check_link_status() due to multiple
> > > detects
> > 
> > How exactly does it do that? Also we shouldn't sweep that under the rug
> > anyway. Instead someone should actually fix the problem that causes the
> > WARN.
> > 
> > > and also avoids DP compliance failures. It avoids doing
> > > a full detect every single time on .detect().
> > > 
> > > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/intel_dp.c | 2 --
> > >  1 file changed, 2 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> > > index db75bb9..9c9277e 100644
> > > --- a/drivers/gpu/drm/i915/intel_dp.c
> > > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > > @@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
> > >  	if (!intel_dp->detect_done)
> > >  		status = intel_dp_long_pulse(intel_dp->attached_connector);
> > >  
> > > -	intel_dp->detect_done = false;
> > > -
> > >  	return status;
> > >  }
> > >  
> > > -- 
> > > 1.9.1
> > 
> > -- 
> > Ville Syrjälä
> > Intel OTC

-- 
Ville Syrjälä
Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH] drm/i915: Do not reset detect_done flag in intel_dp_detect

[Manasi Navare]

On Thu, Dec 08, 2016 at 05:58:44PM +0200, Ville Syrjälä wrote:
> On Wed, Dec 07, 2016 at 07:51:21PM -0800, Manasi Navare wrote:
> > Ville,
> > You mentioned that this detect_done should be set to false also
> > in the resume case so in i915_display_resume where it calls
> > intel_hpd_init that eventually schedules the hpd_poll_init_work and
> > calls drm_helper_hpd_irq_event() which then calls .detect().
> > So in this case if I have to reset this detect_done in the
> > hpd_poll_init_work, how do I make sure I do it only if the
> > connector is DP?
> 
> We have the .reset hook for these sort of things.
>

How can I use .reset hook to set the intel_dp->detect_done flag
to false only for DP connector before
sending drm_hpd_irq_event()?

Manasi 
> > 
> > Manasi 
> > 
> > On Wed, Dec 07, 2016 at 04:05:56PM +0200, Ville Syrjälä wrote:
> > > On Tue, Dec 06, 2016 at 04:43:51PM -0800, Manasi Navare wrote:
> > > > The detect_done flag was introduced in the commit
> > > > 7d23e3c37bb3fc6952dc84007ee60cb533fd2d5c in order to avoid
> > > > multiple detects on hotplug where intel_dp_long_pulse()
> > > > was called from HPD handler as well as in intel_dp_detect.
> > > > So this detect_done flag was required to make sure intel_dp_detect()
> > > > did not call long pulse handler again if it was already been called
> > > > from HPD handler. However commit 1015811609c0328b5ed670d07748591b837e74eb
> > > > differs the long hpd handling entirely until the hotplug work runs to
> > > > avoid the double long hpd handling the "detect_done" flag is trying
> > > > to prevent.
> > > 
> > > That sentence doesn't parse here. Anyways, the flag indeed is now a nop
> > > and your patch is pretty much the same what I did here:
> > > https://patchwork.freedesktop.org/patch/101476/
> > > 
> > > > 
> > > > So now we do not need to reset the detect_done flag to false in
> > > > intel_dp_detect. It will be reset in the intel_dp_hpd_pulse so
> > > > that intel_dp_detect does a full detect. However if the .detect
> > > > gets called during mode enumeration then we do not need to do a
> > > > full detect. This patch avoids the WARNS_ONS during connected boot
> > > > case when it calls intel_dp_check_link_status() due to multiple
> > > > detects
> > > 
> > > How exactly does it do that? Also we shouldn't sweep that under the rug
> > > anyway. Instead someone should actually fix the problem that causes the
> > > WARN.
> > > 
> > > > and also avoids DP compliance failures. It avoids doing
> > > > a full detect every single time on .detect().
> > > > 
> > > > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > > > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > > > ---
> > > >  drivers/gpu/drm/i915/intel_dp.c | 2 --
> > > >  1 file changed, 2 deletions(-)
> > > > 
> > > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> > > > index db75bb9..9c9277e 100644
> > > > --- a/drivers/gpu/drm/i915/intel_dp.c
> > > > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > > > @@ -4470,8 +4470,6 @@ static bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
> > > >  	if (!intel_dp->detect_done)
> > > >  		status = intel_dp_long_pulse(intel_dp->attached_connector);
> > > >  
> > > > -	intel_dp->detect_done = false;
> > > > -
> > > >  	return status;
> > > >  }
> > > >  
> > > > -- 
> > > > 1.9.1
> > > 
> > > -- 
> > > Ville Syrjälä
> > > Intel OTC
> 
> -- 
> Ville Syrjälä
> Intel OTC
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

[PATCH v2] drm/i915/dp: Do not reset detect_done flag in intel_dp_detect

[Dhinakaran Pandiyan]

From: "Navare, Manasi D" <manasi.d.navare@intel.com>

The detect_done flag was introduced in the 'commit 7d23e3c37bb3
("drm/i915: Cleaning up intel_dp_hpd_pulse")' in order to avoid multiple
detects on hotplug where intel_dp_long_pulse() was called from HPD handler
as well as intel_dp_detect(). Later, 'commit 1015811609c0
("drm/i915: Move long hpd handling into the hotplug work")' deferred long
hpd handling to hotplug work to avoid handling it twice. But, resetting the
flag after long hpd handling leads to the code being executed again during
mode enumeration.

So, do not reset the detect_done flag to false in intel_dp_detect. The flag
is reset in intel_dp_hpd_pulse to allow a full detect and set when the
hotplug work does a full DPCD detect. However if .detect() gets called
during enumeration we return the cached status.

v2:
Allow full detect after encoder reset. (Ville)
Set the detect_done even connector if disconnected (DK)
Commit message changes.

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
---
 drivers/gpu/drm/i915/intel_dp.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 45ebc96..5689cf3 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4473,7 +4473,6 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
 	intel_dp_set_edid(intel_dp);
 	if (is_edp(intel_dp) || intel_connector->detect_edid)
 		status = connector_status_connected;
-	intel_dp->detect_done = true;
 
 	/* Try to read the source of the interrupt */
 	if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
@@ -4508,10 +4507,10 @@ intel_dp_detect(struct drm_connector *connector, bool force)
 		      connector->base.id, connector->name);
 
 	/* If full detect is not performed yet, do a full detect */
-	if (!intel_dp->detect_done)
+	if (!intel_dp->detect_done) {
+		intel_dp->detect_done = true;
 		status = intel_dp_long_pulse(intel_dp->attached_connector);
-
-	intel_dp->detect_done = false;
+	}
 
 	return status;
 }
@@ -4803,6 +4802,8 @@ void intel_dp_encoder_reset(struct drm_encoder *encoder)
 	if (lspcon->active)
 		lspcon_resume(lspcon);
 
+	intel_dp->detect_done = false;
+
 	if (to_intel_encoder(encoder)->type != INTEL_OUTPUT_EDP)
 		return;
 
-- 
2.7.4

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH v2] drm/i915/dp: Do not reset detect_done flag in intel_dp_detect

[Jani Nikula]

On Tue, 20 Dec 2016, Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> wrote:
> From: "Navare, Manasi D" <manasi.d.navare@intel.com>
>
> The detect_done flag was introduced in the 'commit 7d23e3c37bb3
> ("drm/i915: Cleaning up intel_dp_hpd_pulse")' in order to avoid multiple
> detects on hotplug where intel_dp_long_pulse() was called from HPD handler
> as well as intel_dp_detect(). Later, 'commit 1015811609c0
> ("drm/i915: Move long hpd handling into the hotplug work")' deferred long
> hpd handling to hotplug work to avoid handling it twice. But, resetting the
> flag after long hpd handling leads to the code being executed again during
> mode enumeration.
>
> So, do not reset the detect_done flag to false in intel_dp_detect. The flag
> is reset in intel_dp_hpd_pulse to allow a full detect and set when the
> hotplug work does a full DPCD detect. However if .detect() gets called
> during enumeration we return the cached status.
>
> v2:
> Allow full detect after encoder reset. (Ville)
> Set the detect_done even connector if disconnected (DK)
> Commit message changes.
>

Fixes: ?

> Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dp.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 45ebc96..5689cf3 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -4473,7 +4473,6 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
>  	intel_dp_set_edid(intel_dp);
>  	if (is_edp(intel_dp) || intel_connector->detect_edid)
>  		status = connector_status_connected;
> -	intel_dp->detect_done = true;
>  
>  	/* Try to read the source of the interrupt */
>  	if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
> @@ -4508,10 +4507,10 @@ intel_dp_detect(struct drm_connector *connector, bool force)
>  		      connector->base.id, connector->name);
>  
>  	/* If full detect is not performed yet, do a full detect */
> -	if (!intel_dp->detect_done)
> +	if (!intel_dp->detect_done) {
> +		intel_dp->detect_done = true;
>  		status = intel_dp_long_pulse(intel_dp->attached_connector);
> -
> -	intel_dp->detect_done = false;
> +	}
>  
>  	return status;
>  }
> @@ -4803,6 +4802,8 @@ void intel_dp_encoder_reset(struct drm_encoder *encoder)
>  	if (lspcon->active)
>  		lspcon_resume(lspcon);
>  
> +	intel_dp->detect_done = false;
> +
>  	if (to_intel_encoder(encoder)->type != INTEL_OUTPUT_EDP)
>  		return;

-- 
Jani Nikula, Intel Open Source Technology Center
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Re: [PATCH v2] drm/i915/dp: Do not reset detect_done flag in intel_dp_detect

[Pandiyan, Dhinakaran]

On Tue, 2016-12-20 at 10:08 +0200, Jani Nikula wrote:
> On Tue, 20 Dec 2016, Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> wrote:
> > From: "Navare, Manasi D" <manasi.d.navare@intel.com>
> >
> > The detect_done flag was introduced in the 'commit 7d23e3c37bb3
> > ("drm/i915: Cleaning up intel_dp_hpd_pulse")' in order to avoid multiple
> > detects on hotplug where intel_dp_long_pulse() was called from HPD handler
> > as well as intel_dp_detect(). Later, 'commit 1015811609c0
> > ("drm/i915: Move long hpd handling into the hotplug work")' deferred long
> > hpd handling to hotplug work to avoid handling it twice. But, resetting the
> > flag after long hpd handling leads to the code being executed again during
> > mode enumeration.
> >
> > So, do not reset the detect_done flag to false in intel_dp_detect. The flag
> > is reset in intel_dp_hpd_pulse to allow a full detect and set when the
> > hotplug work does a full DPCD detect. However if .detect() gets called
> > during enumeration we return the cached status.
> >
> > v2:
> > Allow full detect after encoder reset. (Ville)
> > Set the detect_done even connector if disconnected (DK)
> > Commit message changes.
> >
> 
> Fixes: ?
> 

There have been too many changes here, I don't know which commit to
really blame. Most likely 
Fixes: commit 7d23e3c37bb3 ("drm/i915: Cleaning up intel_dp_hpd_pulse")


-DK

> > Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Cc: Jani Nikula <jani.nikula@linux.intel.com>
> > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
> > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_dp.c | 9 +++++----
> >  1 file changed, 5 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> > index 45ebc96..5689cf3 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -4473,7 +4473,6 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
> >  	intel_dp_set_edid(intel_dp);
> >  	if (is_edp(intel_dp) || intel_connector->detect_edid)
> >  		status = connector_status_connected;
> > -	intel_dp->detect_done = true;
> >  
> >  	/* Try to read the source of the interrupt */
> >  	if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
> > @@ -4508,10 +4507,10 @@ intel_dp_detect(struct drm_connector *connector, bool force)
> >  		      connector->base.id, connector->name);
> >  
> >  	/* If full detect is not performed yet, do a full detect */
> > -	if (!intel_dp->detect_done)
> > +	if (!intel_dp->detect_done) {
> > +		intel_dp->detect_done = true;
> >  		status = intel_dp_long_pulse(intel_dp->attached_connector);
> > -
> > -	intel_dp->detect_done = false;
> > +	}
> >  
> >  	return status;
> >  }
> > @@ -4803,6 +4802,8 @@ void intel_dp_encoder_reset(struct drm_encoder *encoder)
> >  	if (lspcon->active)
> >  		lspcon_resume(lspcon);
> >  
> > +	intel_dp->detect_done = false;
> > +
> >  	if (to_intel_encoder(encoder)->type != INTEL_OUTPUT_EDP)
> >  		return;
> 

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

[PATCH v3] drm/i915/dp: Do not reset detect_done flag in intel_dp_detect

[Dhinakaran Pandiyan]

From: "Navare, Manasi D" <manasi.d.navare@intel.com>

The detect_done flag was introduced in the 'commit 7d23e3c37bb3
("drm/i915: Cleaning up intel_dp_hpd_pulse")' in order to avoid multiple
detects on hotplug where intel_dp_long_pulse() was called from HPD handler
as well as intel_dp_detect(). Later, 'commit 1015811609c0
("drm/i915: Move long hpd handling into the hotplug work")' deferred long
hpd handling to hotplug work to avoid handling it twice. But, resetting the
flag after long hpd handling leads to the code being executed again during
mode enumeration.

So, do not reset the detect_done flag to False in intel_dp_detect(). The
flag is reset in intel_dp_hpd_pulse() to allow a full detect and set when
the hotplug work does a full DPCD detect. However if ->detect() gets called
during mode enumeration after a DPCD detect, return the cached connector
status.

Resetting the flag in the encoder's reset callback should take care of
hotplug between suspend/resume.

v2:
Allow full detect after encoder reset. (Ville)
Set the detect_done flag for connector disconnected case too. (DK)
Commit message changes.

Cc: stable@vger.kernel.org
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Ander Conselvande Oliveira <ander.conselvan.de.oliveira@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Fixes: commit 7d23e3c37bb3 ("drm/i915: Cleaning up intel_dp_hpd_pulse")
Signed-off-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
---
 drivers/gpu/drm/i915/intel_dp.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 45ebc96..5689cf3 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -4473,7 +4473,6 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
 	intel_dp_set_edid(intel_dp);
 	if (is_edp(intel_dp) || intel_connector->detect_edid)
 		status = connector_status_connected;
-	intel_dp->detect_done = true;
 
 	/* Try to read the source of the interrupt */
 	if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11 &&
@@ -4508,10 +4507,10 @@ intel_dp_detect(struct drm_connector *connector, bool force)
 		      connector->base.id, connector->name);
 
 	/* If full detect is not performed yet, do a full detect */
-	if (!intel_dp->detect_done)
+	if (!intel_dp->detect_done) {
+		intel_dp->detect_done = true;
 		status = intel_dp_long_pulse(intel_dp->attached_connector);
-
-	intel_dp->detect_done = false;
+	}
 
 	return status;
 }
@@ -4803,6 +4802,8 @@ void intel_dp_encoder_reset(struct drm_encoder *encoder)
 	if (lspcon->active)
 		lspcon_resume(lspcon);
 
+	intel_dp->detect_done = false;
+
 	if (to_intel_encoder(encoder)->type != INTEL_OUTPUT_EDP)
 		return;
 
-- 
2.7.4