Greg KH wrote:
> On Thu, Nov 23, 2017 at 10:09:25PM +0100, Rainer Fiebig wrote:
>> Rainer Fiebig wrote:
>>> Maarten Lankhorst wrote:
>>>> Op 20-11-17 om 09:51 schreef Rainer Fiebig:
>>>>> Jani Nikula wrote:
>>>>>> On Sun, 19 Nov 2017, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>>>>>>> On Sun, Nov 19, 2017 at 01:44:06PM +0100, Rainer Fiebig wrote:
>>>>>>>> Greg KH wrote:
>>>>>>>>> On Sun, Nov 19, 2017 at 12:56:26PM +0100, Rainer Fiebig wrote:
>>>>>>>>>> Greg KH wrote:
>>>>>>>>>>> On Sat, Nov 18, 2017 at 05:08:20PM +0100, Rainer Fiebig wrote:
>>>>>>>>>>>> Greg KH wrote:
>>>>>>>>>>>>> On Sat, Nov 18, 2017 at 01:47:32PM +0100, Rainer Fiebig wrote:
>>>>>>>>>>>>>> Hi!
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Hopefully the right addressee.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Encountered two bad backports which cause screen-flicker.
>>>>>>>>>>>>>> dmesg shows:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> ...
>>>>>>>>>>>>>> [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
>>>>>>>>>>>>>> [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun
>>>>>>>>>>>>>> [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun
>>>>>>>>>>>>>> [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder B FIFO underrun
>>>>>>>>>>>>>> ...
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> CPU: Intel Core i3 (Clarkdale/Ironlake)
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> The backports are:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> - diff --git a/drivers/gpu/drm/i915/intel_pm.c
>>>>>>>>>>>>>> b/drivers/gpu/drm/i915/intel_pm.c
>>>>>>>>>>>>>> index 49de476..277a802 100644
>>>>>>>>>>>>>> - diff --git a/drivers/gpu/drm/i915/intel_drv.h
>>>>>>>>>>>>>> b/drivers/gpu/drm/i915/intel_drv.h
>>>>>>>>>>>>>> index a19ec06..3ce9ba3 100644
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> After reversing them the flicker is gone, no more messages in dmesg. All
>>>>>>>>>>>>>> else OK so far.
>>>>>>>>>>>>> So which commit was the one that caused the problem? I will be glad to
>>>>>>>>>>>>> revert it.
>>>>>>>>>>>>>
>>>>>>>>>>>>> thanks,
>>>>>>>>>>>>>
>>>>>>>>>>>>> greg k-h
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>> I started by reverting the more complex one first ("index
>>>>>>>>>>>> 49de476..277a802100644"). But the kernel wouldn't compile then.
>>>>>>>>>>> What git commit id is that? I don't see those ids in the 4.9-stable
>>>>>>>>>>> tree.
>>>>>>>>>>>
>>>>>>>>>>>> So I also reverted "index a19ec06..3ce9ba3 100644". After that the
>>>>>>>>>>>> kernel compiled just fine and the problems were gone (still are).
>>>>>>>>>>> Same here, what git commit id was this?
>>>>>>>>>>>
>>>>>>>>>>> thanks,
>>>>>>>>>>>
>>>>>>>>>>> greg k-h
>>>>>>>>>>>
>>>>>>>>>> OK, no mistake. IIRC, I took the patches (and the IDs) from the
>>>>>>>>>> changelog for patch-4.9.62. I've attached both, so you can check yourself.
>>>>>>>>>>
>>>>>>>>>> I've also applied a freshly downloaded patch-4.9.62 to a freshly
>>>>>>>>>> expanded 4.9 and re-compiled. The flicker is there. I haven't yet
>>>>>>>>>> reverted the two patches but I'm confident that after having done so the
>>>>>>>>>> flicker will be gone. If not I'll let you know.
>>>>>>>>>>
>>>>>>>>>> As a good news: 4.14 is *not* affected. So to me it seems those two
>>>>>>>>>> patches are part of sort of a package and can not be backported alone.
>>>>>>>>>>
>>>>>>>>>> So long!
>>>>>>>>>> Rainer Fiebig
>>>>>>>>>> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
>>>>>>>>>> index 49de476..277a802 100644
>>>>>>>>>> --- a/drivers/gpu/drm/i915/intel_pm.c
>>>>>>>>>> +++ b/drivers/gpu/drm/i915/intel_pm.c
>>>>>>>>>> @@ -27,6 +27,7 @@
>>>>>>>>>>
>>>>>>>>>> #include <linux/cpufreq.h>
>>>>>>>>>> #include <drm/drm_plane_helper.h>
>>>>>>>>>> +#include <drm/drm_atomic_helper.h>
>>>>>>>>>> #include "i915_drv.h"
>>>>>>>>>> #include "intel_drv.h"
>>>>>>>>>> #include "../../../platform/x86/intel_ips.h"
>>>>>>>>>> @@ -2017,9 +2018,9 @@ static void ilk_compute_wm_level(const struct drm_i915_private *dev_priv,
>>>>>>>>>> const struct intel_crtc *intel_crtc,
>>>>>>>>>> int level,
>>>>>>>>>> struct intel_crtc_state *cstate,
>>>>>>>>>> - struct intel_plane_state *pristate,
>>>>>>>>>> - struct intel_plane_state *sprstate,
>>>>>>>>>> - struct intel_plane_state *curstate,
>>>>>>>>>> + const struct intel_plane_state *pristate,
>>>>>>>>>> + const struct intel_plane_state *sprstate,
>>>>>>>>>> + const struct intel_plane_state *curstate,
>>>>>>>>>> struct intel_wm_level *result)
>>>>>>>>>> {
>>>>>>>>>> uint16_t pri_latency = dev_priv->wm.pri_latency[level];
>>>>>>>>>> @@ -2341,28 +2342,24 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate)
>>>>>>>>>> struct intel_pipe_wm *pipe_wm;
>>>>>>>>>> struct drm_device *dev = state->dev;
>>>>>>>>>> const struct drm_i915_private *dev_priv = to_i915(dev);
>>>>>>>>>> - struct intel_plane *intel_plane;
>>>>>>>>>> - struct intel_plane_state *pristate = NULL;
>>>>>>>>>> - struct intel_plane_state *sprstate = NULL;
>>>>>>>>>> - struct intel_plane_state *curstate = NULL;
>>>>>>>>>> + struct drm_plane *plane;
>>>>>>>>>> + const struct drm_plane_state *plane_state;
>>>>>>>>>> + const struct intel_plane_state *pristate = NULL;
>>>>>>>>>> + const struct intel_plane_state *sprstate = NULL;
>>>>>>>>>> + const struct intel_plane_state *curstate = NULL;
>>>>>>>>>> int level, max_level = ilk_wm_max_level(dev), usable_level;
>>>>>>>>>> struct ilk_wm_maximums max;
>>>>>>>>>>
>>>>>>>>>> pipe_wm = &cstate->wm.ilk.optimal;
>>>>>>>>>>
>>>>>>>>>> - for_each_intel_plane_on_crtc(dev, intel_crtc, intel_plane) {
>>>>>>>>>> - struct intel_plane_state *ps;
>>>>>>>>>> + drm_atomic_crtc_state_for_each_plane_state(plane, plane_state, &cstate->base) {
>>>>>>>>>> + const struct intel_plane_state *ps = to_intel_plane_state(plane_state);
>>>>>>>>>>
>>>>>>>>>> - ps = intel_atomic_get_existing_plane_state(state,
>>>>>>>>>> - intel_plane);
>>>>>>>>>> - if (!ps)
>>>>>>>>>> - continue;
>>>>>>>>>> -
>>>>>>>>>> - if (intel_plane->base.type == DRM_PLANE_TYPE_PRIMARY)
>>>>>>>>>> + if (plane->type == DRM_PLANE_TYPE_PRIMARY)
>>>>>>>>>> pristate = ps;
>>>>>>>>>> - else if (intel_plane->base.type == DRM_PLANE_TYPE_OVERLAY)
>>>>>>>>>> + else if (plane->type == DRM_PLANE_TYPE_OVERLAY)
>>>>>>>>>> sprstate = ps;
>>>>>>>>>> - else if (intel_plane->base.type == DRM_PLANE_TYPE_CURSOR)
>>>>>>>>>> + else if (plane->type == DRM_PLANE_TYPE_CURSOR)
>>>>>>>>>> curstate = ps;
>>>>>>>>>> }
>>>>>>>>>>
>>>>>>>>>> @@ -2384,11 +2381,9 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate)
>>>>>>>>>> if (pipe_wm->sprites_scaled)
>>>>>>>>>> usable_level = 0;
>>>>>>>>>>
>>>>>>>>>> - ilk_compute_wm_level(dev_priv, intel_crtc, 0, cstate,
>>>>>>>>>> - pristate, sprstate, curstate, &pipe_wm->raw_wm[0]);
>>>>>>>>>> -
>>>>>>>>>> memset(&pipe_wm->wm, 0, sizeof(pipe_wm->wm));
>>>>>>>>>> - pipe_wm->wm[0] = pipe_wm->raw_wm[0];
>>>>>>>>>> + ilk_compute_wm_level(dev_priv, intel_crtc, 0, cstate,
>>>>>>>>>> + pristate, sprstate, curstate, &pipe_wm->wm[0]);
>>>>>>>>>>
>>>>>>>>>> if (IS_HASWELL(dev) || IS_BROADWELL(dev))
>>>>>>>>>> pipe_wm->linetime = hsw_compute_linetime_wm(cstate);
>>>>>>>>>> @@ -2398,8 +2393,8 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate)
>>>>>>>>>>
>>>>>>>>>> ilk_compute_wm_reg_maximums(dev, 1, &max);
>>>>>>>>>>
>>>>>>>>>> - for (level = 1; level <= max_level; level++) {
>>>>>>>>>> - struct intel_wm_level *wm = &pipe_wm->raw_wm[level];
>>>>>>>>>> + for (level = 1; level <= usable_level; level++) {
>>>>>>>>>> + struct intel_wm_level *wm = &pipe_wm->wm[level];
>>>>>>>>>>
>>>>>>>>>> ilk_compute_wm_level(dev_priv, intel_crtc, level, cstate,
>>>>>>>>>> pristate, sprstate, curstate, wm);
>>>>>>>>>> @@ -2409,13 +2404,10 @@ static int ilk_compute_pipe_wm(struct intel_crtc_state *cstate)
>>>>>>>>>> * register maximums since such watermarks are
>>>>>>>>>> * always invalid.
>>>>>>>>>> */
>>>>>>>>>> - if (level > usable_level)
>>>>>>>>>> - continue;
>>>>>>>>>> -
>>>>>>>>>> - if (ilk_validate_wm_level(level, &max, wm))
>>>>>>>>>> - pipe_wm->wm[level] = *wm;
>>>>>>>>>> - else
>>>>>>>>>> - usable_level = level;
>>>>>>>>>> + if (!ilk_validate_wm_level(level, &max, wm)) {
>>>>>>>>>> + memset(wm, 0, sizeof(*wm));
>>>>>>>>>> + break;
>>>>>>>>>> + }
>>>>>>>>>> }
>>>>>>>>>>
>>>>>>>>>> return 0;
>>>>>>>>>> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
>>>>>>>>>> index a19ec06..3ce9ba3 100644
>>>>>>>>>> --- a/drivers/gpu/drm/i915/intel_drv.h
>>>>>>>>>> +++ b/drivers/gpu/drm/i915/intel_drv.h
>>>>>>>>>> @@ -457,7 +457,6 @@ struct intel_crtc_scaler_state {
>>>>>>>>>>
>>>>>>>>>> struct intel_pipe_wm {
>>>>>>>>>> struct intel_wm_level wm[5];
>>>>>>>>>> - struct intel_wm_level raw_wm[5];
>>>>>>>>>> uint32_t linetime;
>>>>>>>>>> bool fbc_wm_enabled;
>>>>>>>>>> bool pipe_enabled;
>>>>>>>>> Ok, so this looks like commit 8777b927b92cf5b6c29f9f9d3c737addea9ac8a7
>>>>>>>>> upstream which is commit 7de694782cbe7840f2c0de6f1e70f41fc1b8b6e8 in
>>>>>>>>> 4.9.62.
>>>>>>>>>
>>>>>>>>> I've cc:ed the authors of that patch now.
>>>>>>>>>
>>>>>>>>> Maarten, any hints? Should I revert this from 4.9-stable, or was there
>>>>>>>>> a follow-on patch that resolved this issue in mainline?
>>>>>>>>>
>>>>>>>>> thanks,
>>>>>>>>>
>>>>>>>>> greg k-h
>>>>>>>>>
>>>>>>>> OK, after reverting the patches, the flicker *is* gone.
>>>>>>> Thanks for confirming this.
>>>>>>>
>>>>>>>> BTW (for the future): Was it the right way to address
>>>>>>>> stable@xxxxxxxxxxxxxxx in this matter or would the bugreport at
>>>>>>>> freedesktop.org have been enough? I'm a bit unsure about that.
>>>>>>> I have no idea what the i915 developers want, but as far as I'm
>>>>>>> concerned, sending this to stable@vger was fine with me, I have no
>>>>>>> problem doing a bit of work in tracking down the specific patch before
>>>>>>> bugging the developers involved.
>>>>>> Well, this one we wanted to be backported, and so indicated with cc:
>>>>>> stable, but apparently it went south anyway. :(
>>>>>>
>>>>>> Rainer, does v4.14 work for you? I.e. is the commit okay or not before
>>>>>> the backport?
>>>>>>
>>>>>> Maarten?
>>>>>>
>>>>>> BR,
>>>>>> Jani.
>>>>>>
>>>>>>
>>>>> 4.14 is OK, no problems.
>>>>>
>>>>> So long!
>>>>> Rainer Fiebig
>>>>
>>>> What happens when you apply both other backported patches on top?
>>>>
>>>> https://cgit.freedesktop.org/~mlankhorst/linux/log/?h=v4.9
>>>>
>>>
>>> So I applied the 2 new patches on top of the orig. 4.9.62.
>>>
>>> Better now but not yet completely OK:
>>>
>>> ...
>>> [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
>>> [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun
>>> ...
>>>
>>> No random flicker so far but flicker when I enter a character in an
>>> x-terminal.
>>>
>>> Seems your patches fixed only half of the pipes. ;)
>>>
>>> So long!
>>> Rainer Fiebig
>>>
>>
>> There's also random flicker after a while.
>
> Ok, I'm just going to revert this patch for the next release unless one
> of the i915 developers has a better idea...
>
> thanks,
>
> greg k-h
>
Right decision, thanks! I'm still offering to test patches in this
matter once the devs think they've figured it out.
So long!
Rainer Fiebig
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