[Intel-gfx] [PATCH v2] drm/i915: Don't enable IPS when pixel rate exceeds 95% of cdclk

Rodrigo Vivi rodrigo.vivi at gmail.com
Wed May 20 13:40:16 PDT 2015


I'm convinced Unclaimed regs Paulo saw came from somewhere else since
I just got it with pm_rpm rte with no patch applied....

So I'd suggest to merge this patch... Although it also doesn't fix the
flicker I see here so the bug would still be open...

Anyway,
Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>

On Thu, Sep 18, 2014 at 4:56 AM, Jani Nikula
<jani.nikula at linux.intel.com> wrote:
> On Wed, 17 Sep 2014, Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:
>> On Wed, Sep 17, 2014 at 11:10:48AM -0300, Paulo Zanoni wrote:
>>> 2014-09-17 11:05 GMT-03:00 Paulo Zanoni <przanoni at gmail.com>:
>>> > 2014-09-15 4:22 GMT-03:00 Jani Nikula <jani.nikula at linux.intel.com>:
>>> >> On Fri, 12 Sep 2014, Ville Syrjälä <ville.syrjala at linux.intel.com> wrote:
>>> >>> On Fri, Sep 12, 2014 at 04:42:33PM +0100, Chris Wilson wrote:
>>> >>>> On Fri, Sep 12, 2014 at 05:01:57PM +0300, ville.syrjala at linux.intel.com wrote:
>>> >>>> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
>>> >>>> >
>>> >>>> > Bspec says we shouldn't enable IPS on BDW when the pipe pixel rate
>>> >>>> > exceeds 95% of the core display clock. Apparently this can cause
>>> >>>> > underruns.
>>> >>>> >
>>> >>>> > There's no similar restriction listed for HSW, so leave that one alone
>>> >>>> > for now.
>>> >>>> >
>>> >>>> > v2: Add pipe_config_supports_ips() (Chris)
>>> >>>> >
>>> >>>> > Tested-by: Timo Aaltonen <tjaalton at ubuntu.com>
>>> >>>> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83497
>>> >>>> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
>>> >>>> > ---
>>> >>>> >  drivers/gpu/drm/i915/intel_display.c | 21 +++++++++++++++++++--
>>> >>>> >  drivers/gpu/drm/i915/intel_drv.h     |  1 +
>>> >>>> >  drivers/gpu/drm/i915/intel_pm.c      | 16 +++++++---------
>>> >>>> >  3 files changed, 27 insertions(+), 11 deletions(-)
>>> >>>> >
>>> >>>> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>>> >>>> > index 965eb3c..7809177 100644
>>> >>>> > --- a/drivers/gpu/drm/i915/intel_display.c
>>> >>>> > +++ b/drivers/gpu/drm/i915/intel_display.c
>>> >>>> > @@ -5241,12 +5241,29 @@ retry:
>>> >>>> >    return setup_ok ? 0 : -EINVAL;
>>> >>>> >  }
>>> >>>> >
>>> >>>> > +static bool pipe_config_supports_ips(struct drm_i915_private *dev_priv,
>>> >>>> > +                               struct intel_crtc_config *pipe_config)
>>> >>>> > +{
>>> >>>> > +  if (pipe_config->pipe_bpp > 24)
>>> >>>> > +          return false;
>>> >>>> > +
>>> >>>> > +  /* HSW can handle pixel rate up to cdclk? */
>>> >>>> > +  if (IS_HASWELL(dev_priv->dev))
>>> >>>>
>>> >>>> This only needs IS_HASWELL(dev_priv)
>>> >>>
>>> >>> old habits...
>>> >>
>>> >> Thanks to your old habits I didn't have to make any changes when pushing
>>> >> this to drm-intel-fixes which is still old habit land. Thanks for the
>>> >> patch and review.
>>>
>>> And another detail: even if the register read worked, we'd have
>>> printed a bad value since the cdclock is disabled at the moment we run
>>> the function, so we'd return the FCLK frequency. So maybe we need to
>>> cache the value of the "cdclk under normal display operation" and
>>> reuse it here.
>>
>> Yeah. We already do that on VLV/CHV to some extent. We should just do
>> it for all platforms. Although for this case what we'd need to do is
>> precalculate the optimal cdclk during compute_config phase and use
>> that value for these checks, and then during global_resources we
>> actually change the cdclk to match the precomputed value.
>>
>> Also if someone takes this on they could also unify the ddi cdclk
>> code to look more like the other platforms, and perhaps even implement
>> support for changing the cdclk frequency on HSW/BDW ;)
>
> I've dropped the commit from drm-intel-fixes and reopened the bug. We
> need someone(tm) to look at this now.
>
> BR,
> Jani.
>
>
>
>>
>>>
>>> >
>>> > This patches causes a regression on igt/pm_rpm/rte:
>>> >
>>> > [   44.871662] [drm:intel_dp_compute_config] DP link bw required
>>> > 650358 available 1728000
>>> > [   44.871666] ------------[ cut here ]------------
>>> > [   44.871691] WARNING: CPU: 0 PID: 1745 at
>>> > drivers/gpu/drm/i915/intel_uncore.c:47
>>> > assert_device_not_suspended.isra.8+0x43/0x50 [i915]()
>>> > [   44.871692] Device suspended
>>> > [   44.871694] Modules linked in: hid_multitouch hid_sensor_hub
>>> > snd_hda_codec_hdmi intel_rapl x86_pkg_temp_thermal intel_powerclamp
>>> > efivars snd_hda_intel btusb snd_hda_controller snd_hda_codec snd_hwdep
>>> > iwlmvm snd_pcm_oss snd_mixer_oss iwlwifi mei_me mei snd_pcm snd_timer
>>> > int3403_thermal i2c_designware_platform i2c_designware_core acpi_pad
>>> > fuse nls_utf8 nls_cp437 vfat fat i915 sdhci_pci drm_kms_helper e1000e
>>> > drm sdhci_acpi sdhci
>>> > [   44.871726] CPU: 0 PID: 1745 Comm: pm_rpm Not tainted
>>> > 3.17.0-rc5.1409171019pz+ #1120
>>> > [   44.871728] Hardware name: Intel Corporation Broadwell Client
>>> > platform/Wilson Beach SDS, BIOS BDW-E2R1.86C.0072.R03.1405072127
>>> > 05/07/2014
>>> > [   44.871730]  0000000000000009 ffff8800aa763a90 ffffffff816ec803
>>> > ffff8800aa763ad8
>>> > [   44.871735]  ffff8800aa763ac8 ffffffff8107a0c8 ffff88023ec20068
>>> > 0000000000130040
>>> > [   44.871739]  ffff88023f12b3d8 0000000000130040 ffff88023ec20000
>>> > ffff8800aa763b28
>>> > [   44.871743] Call Trace:
>>> > [   44.871749]  [<ffffffff816ec803>] dump_stack+0x4d/0x66
>>> > [   44.871754]  [<ffffffff8107a0c8>] warn_slowpath_common+0x78/0xa0
>>> > [   44.871758]  [<ffffffff8107a137>] warn_slowpath_fmt+0x47/0x50
>>> > [   44.871783]  [<ffffffffa015a1f4>] ?
>>> > intel_dp_compute_config+0x274/0x600 [i915]
>>> > [   44.871803]  [<ffffffffa0122cf3>]
>>> > assert_device_not_suspended.isra.8+0x43/0x50 [i915]
>>> > [   44.871822]  [<ffffffffa0125a20>] gen6_read32+0x30/0x150 [i915]
>>> > [   44.871844]  [<ffffffffa0154636>] intel_ddi_get_cdclk_freq+0xd6/0x140 [i915]
>>> > [   44.871865]  [<ffffffffa0139a92>] __intel_set_mode+0x1672/0x1750 [i915]
>>> > [   44.871886]  [<ffffffffa01418e1>] intel_set_mode+0x11/0x30 [i915]
>>> > [   44.871906]  [<ffffffffa01429ed>] intel_crtc_set_config+0xa9d/0xeb0 [i915]
>>> > [   44.871923]  [<ffffffffa0026283>]
>>> > drm_mode_set_config_internal+0x63/0x100 [drm]
>>> > [   44.871938]  [<ffffffffa002a7e3>] drm_mode_setcrtc+0x283/0x580 [drm]
>>> > [   44.871948]  [<ffffffffa001c81f>] drm_ioctl+0x1df/0x6a0 [drm]
>>> > [   44.871954]  [<ffffffff811e07b0>] do_vfs_ioctl+0x2e0/0x4e0
>>> > [   44.871957]  [<ffffffff816f6af7>] ? sysret_check+0x1b/0x56
>>> > [   44.871962]  [<ffffffff810bfb0d>] ? trace_hardirqs_on_caller+0x15d/0x200
>>> > [   44.871966]  [<ffffffff811e0a31>] SyS_ioctl+0x81/0xa0
>>> > [   44.871969]  [<ffffffff816f6ad2>] system_call_fastpath+0x16/0x1b
>>> > [   44.871972] ---[ end trace 91bf8920a2c6b824 ]---
>>> > [   44.871975] ------------[ cut here ]------------
>>> > [   44.871994] WARNING: CPU: 0 PID: 1745 at
>>> > drivers/gpu/drm/i915/intel_uncore.c:528
>>> > hsw_unclaimed_reg_debug+0x6d/0x80 [i915]()
>>> > [   44.871996] Unclaimed register detected before reading register 0x130040
>>> > [   44.871997] Modules linked in: hid_multitouch hid_sensor_hub
>>> > snd_hda_codec_hdmi intel_rapl x86_pkg_temp_thermal intel_powerclamp
>>> > efivars snd_hda_intel btusb snd_hda_controller snd_hda_codec snd_hwdep
>>> > iwlmvm snd_pcm_oss snd_mixer_oss iwlwifi mei_me mei snd_pcm snd_timer
>>> > int3403_thermal i2c_designware_platform i2c_designware_core acpi_pad
>>> > fuse nls_utf8 nls_cp437 vfat fat i915 sdhci_pci drm_kms_helper e1000e
>>> > drm sdhci_acpi sdhci
>>> > [   44.872025] CPU: 0 PID: 1745 Comm: pm_rpm Tainted: G        W
>>> > 3.17.0-rc5.1409171019pz+ #1120
>>> > [   44.872026] Hardware name: Intel Corporation Broadwell Client
>>> > platform/Wilson Beach SDS, BIOS BDW-E2R1.86C.0072.R03.1405072127
>>> > 05/07/2014
>>> > [   44.872028]  0000000000000009 ffff8800aa763a88 ffffffff816ec803
>>> > ffff8800aa763ad0
>>> > [   44.872032]  ffff8800aa763ac0 ffffffff8107a0c8 ffff88023ec20000
>>> > 0000000000130040
>>> > [   44.872035]  ffff88023f12b3d8 0000000000130040 ffff88023ec20000
>>> > ffff8800aa763b20
>>> > [   44.872039] Call Trace:
>>> > [   44.872042]  [<ffffffff816ec803>] dump_stack+0x4d/0x66
>>> > [   44.872046]  [<ffffffff8107a0c8>] warn_slowpath_common+0x78/0xa0
>>> > [   44.872049]  [<ffffffff8107a137>] warn_slowpath_fmt+0x47/0x50
>>> > [   44.872068]  [<ffffffffa0122bbd>] hsw_unclaimed_reg_debug+0x6d/0x80 [i915]
>>> > [   44.872087]  [<ffffffffa0125a41>] gen6_read32+0x51/0x150 [i915]
>>> > [   44.872109]  [<ffffffffa0154636>] intel_ddi_get_cdclk_freq+0xd6/0x140 [i915]
>>> > [   44.872129]  [<ffffffffa0139a92>] __intel_set_mode+0x1672/0x1750 [i915]
>>> > [   44.872149]  [<ffffffffa01418e1>] intel_set_mode+0x11/0x30 [i915]
>>> > [   44.872168]  [<ffffffffa01429ed>] intel_crtc_set_config+0xa9d/0xeb0 [i915]
>>> > [   44.872182]  [<ffffffffa0026283>]
>>> > drm_mode_set_config_internal+0x63/0x100 [drm]
>>> > [   44.872196]  [<ffffffffa002a7e3>] drm_mode_setcrtc+0x283/0x580 [drm]
>>> > [   44.872205]  [<ffffffffa001c81f>] drm_ioctl+0x1df/0x6a0 [drm]
>>> > [   44.872210]  [<ffffffff811e07b0>] do_vfs_ioctl+0x2e0/0x4e0
>>> > [   44.872213]  [<ffffffff816f6af7>] ? sysret_check+0x1b/0x56
>>> > [   44.872218]  [<ffffffff810bfb0d>] ? trace_hardirqs_on_caller+0x15d/0x200
>>> > [   44.872221]  [<ffffffff811e0a31>] SyS_ioctl+0x81/0xa0
>>> > [   44.872224]  [<ffffffff816f6ad2>] system_call_fastpath+0x16/0x1b
>>> > [   44.872226] ---[ end trace 91bf8920a2c6b825 ]---
>>> > [   44.872228] ------------[ cut here ]------------
>>> > [   44.872246] WARNING: CPU: 0 PID: 1745 at
>>> > drivers/gpu/drm/i915/intel_uncore.c:528
>>> > hsw_unclaimed_reg_debug+0x6d/0x80 [i915]()
>>> > [   44.872248] Unclaimed register detected after reading register 0x130040
>>> > [   44.872249] Modules linked in: hid_multitouch hid_sensor_hub
>>> > snd_hda_codec_hdmi intel_rapl x86_pkg_temp_thermal intel_powerclamp
>>> > efivars snd_hda_intel btusb snd_hda_controller snd_hda_codec snd_hwdep
>>> > iwlmvm snd_pcm_oss snd_mixer_oss iwlwifi mei_me mei snd_pcm snd_timer
>>> > int3403_thermal i2c_designware_platform i2c_designware_core acpi_pad
>>> > fuse nls_utf8 nls_cp437 vfat fat i915 sdhci_pci drm_kms_helper e1000e
>>> > drm sdhci_acpi sdhci
>>> > [   44.872276] CPU: 0 PID: 1745 Comm: pm_rpm Tainted: G        W
>>> > 3.17.0-rc5.1409171019pz+ #1120
>>> > [   44.872277] Hardware name: Intel Corporation Broadwell Client
>>> > platform/Wilson Beach SDS, BIOS BDW-E2R1.86C.0072.R03.1405072127
>>> > 05/07/2014
>>> > [   44.872279]  0000000000000009 ffff8800aa763a88 ffffffff816ec803
>>> > ffff8800aa763ad0
>>> > [   44.872282]  ffff8800aa763ac0 ffffffff8107a0c8 ffff88023ec20000
>>> > 0000000000130040
>>> > [   44.872286]  00000000ffffffff 0000000000130040 ffff88023ec20000
>>> > ffff8800aa763b20
>>> > [   44.872289] Call Trace:
>>> > [   44.872293]  [<ffffffff816ec803>] dump_stack+0x4d/0x66
>>> > [   44.872296]  [<ffffffff8107a0c8>] warn_slowpath_common+0x78/0xa0
>>> > [   44.872299]  [<ffffffff8107a137>] warn_slowpath_fmt+0x47/0x50
>>> > [   44.872318]  [<ffffffffa0122bbd>] hsw_unclaimed_reg_debug+0x6d/0x80 [i915]
>>> > [   44.872335]  [<ffffffffa0125a7e>] gen6_read32+0x8e/0x150 [i915]
>>> > [   44.872356]  [<ffffffffa0154636>] intel_ddi_get_cdclk_freq+0xd6/0x140 [i915]
>>> > [   44.872376]  [<ffffffffa0139a92>] __intel_set_mode+0x1672/0x1750 [i915]
>>> > [   44.872396]  [<ffffffffa01418e1>] intel_set_mode+0x11/0x30 [i915]
>>> > [   44.872416]  [<ffffffffa01429ed>] intel_crtc_set_config+0xa9d/0xeb0 [i915]
>>> > [   44.872429]  [<ffffffffa0026283>]
>>> > drm_mode_set_config_internal+0x63/0x100 [drm]
>>> > [   44.872443]  [<ffffffffa002a7e3>] drm_mode_setcrtc+0x283/0x580 [drm]
>>> > [   44.872453]  [<ffffffffa001c81f>] drm_ioctl+0x1df/0x6a0 [drm]
>>> > [   44.872458]  [<ffffffff811e07b0>] do_vfs_ioctl+0x2e0/0x4e0
>>> > [   44.872461]  [<ffffffff816f6af7>] ? sysret_check+0x1b/0x56
>>> > [   44.872465]  [<ffffffff810bfb0d>] ? trace_hardirqs_on_caller+0x15d/0x200
>>> > [   44.872468]  [<ffffffff811e0a31>] SyS_ioctl+0x81/0xa0
>>> > [   44.872471]  [<ffffffff816f6ad2>] system_call_fastpath+0x16/0x1b
>>> > [   44.872473] ---[ end trace 91bf8920a2c6b826 ]---
>>> > [   44.872512] [drm:intel_modeset_pipe_config] plane bpp: 24, pipe
>>> > bpp: 18, dithering: 1
>>> >
>>> >>
>>> >> BR,
>>> >> Jani.
>>> >>
>>> >>
>>> >>>
>>> >>>>
>>> >>>> > +          return true;
>>> >>>> > +
>>> >>>> > +  return ilk_pipe_pixel_rate(pipe_config) <=
>>> >>>> > +          intel_ddi_get_cdclk_freq(dev_priv) * 95 / 100;
>>> >>>>
>>> >>>> Otherwise
>>> >>>> Acked-by: Chris Wilson <chris at chris-wilson.co.uk>
>>> >>>> -Chris
>>> >>>>
>>> >>>> --
>>> >>>> Chris Wilson, Intel Open Source Technology Centre
>>> >>>
>>> >>> --
>>> >>> Ville Syrjälä
>>> >>> Intel OTC
>>> >>> _______________________________________________
>>> >>> Intel-gfx mailing list
>>> >>> Intel-gfx at lists.freedesktop.org
>>> >>> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>>> >>
>>> >> --
>>> >> Jani Nikula, Intel Open Source Technology Center
>>> >> _______________________________________________
>>> >> Intel-gfx mailing list
>>> >> Intel-gfx at lists.freedesktop.org
>>> >> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>>> >
>>> >
>>> >
>>> > --
>>> > Paulo Zanoni
>>>
>>>
>>>
>>> --
>>> Paulo Zanoni
>>
>> --
>> Ville Syrjälä
>> Intel OTC
>
> --
> Jani Nikula, Intel Open Source Technology Center
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx



-- 
Rodrigo Vivi
Blog: http://blog.vivi.eng.br


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