| Message ID | 20200429025528.236678-1-acelan.kao@canonical.com |
|---|---|
| Headers | show |
| Series | Intermittent display blackouts on event | expand |
This affects also: Groovy: 802cf455226c (clean apply) Eoan: 128a27cef42a (clean apply) OEM-OSP1-B: b9fc3db3ffa2 (need backport) On 2020-04-29 10:55, AceLan Kao wrote: > BugLink: https://bugs.launchpad.net/bugs/1875254 > > [Impact] > When audio device enters runpm D3(idle for 7 seconds) and then wakes it up > to make a sound, it flicks the screen. > This behavior could be observed while plug/remove AC cable or USB disk, > or open a terminal and press backsapce key. > > [Fix] > This issue could be fixed by this commit, it fixes the flicker during > boot-time, but it also fixes the flicker during rumtime wakeup. > 1ee48a61aa57 drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only > > Audio drivers communicate with i915 over HDA bus multiple times during > system boot-up and each of these transactions result in matching > get_power/put_power calls to i915, and depending on the platform, > a modeset change causing visible flicker. > > GLK is the only platform with minimum CDCLK significantly lower > than BCLK, and thus for GLK setting a higher CDCLK is mandatory. > > For other platforms, minimum CDCLK is close but below 2*BCLK > (e.g. on ICL, CDCLK=176.4kHz with BCLK=96kHz). Spec-wise the constraint > should be set, but in practise no communication errors have been > reported and the downside if set is the flicker observed at boot-time. > > [Test] > Verified on Dell XPS 13 9300 > > [Regression Potential] > Low, it fixes below commit which contains in ubuntu kernel and should have > been applied on ubuntu kernel, too. > Fixes: f6ec9483091f ("drm/i915: extend audio CDCLK>=2*BCLK constraint to more platforms") > > Kai Vehmanen (1): > drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only > > drivers/gpu/drm/i915/display/intel_audio.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) >
On 29.04.20 04:55, AceLan Kao wrote: > BugLink: https://bugs.launchpad.net/bugs/1875254 > > [Impact] > When audio device enters runpm D3(idle for 7 seconds) and then wakes it up > to make a sound, it flicks the screen. > This behavior could be observed while plug/remove AC cable or USB disk, > or open a terminal and press backsapce key. > > [Fix] > This issue could be fixed by this commit, it fixes the flicker during > boot-time, but it also fixes the flicker during rumtime wakeup. > 1ee48a61aa57 drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only > > Audio drivers communicate with i915 over HDA bus multiple times during > system boot-up and each of these transactions result in matching > get_power/put_power calls to i915, and depending on the platform, > a modeset change causing visible flicker. > > GLK is the only platform with minimum CDCLK significantly lower > than BCLK, and thus for GLK setting a higher CDCLK is mandatory. > > For other platforms, minimum CDCLK is close but below 2*BCLK > (e.g. on ICL, CDCLK=176.4kHz with BCLK=96kHz). Spec-wise the constraint > should be set, but in practise no communication errors have been > reported and the downside if set is the flicker observed at boot-time. > > [Test] > Verified on Dell XPS 13 9300 > > [Regression Potential] > Low, it fixes below commit which contains in ubuntu kernel and should have > been applied on ubuntu kernel, too. > Fixes: f6ec9483091f ("drm/i915: extend audio CDCLK>=2*BCLK constraint to more platforms") > > Kai Vehmanen (1): > drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only > > drivers/gpu/drm/i915/display/intel_audio.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > There is an Eoan patch as well. They appear sensible to me. Acked-by: Stefan Bader <stefan.bader@canonical.com>
On 29.04.20 04:55, AceLan Kao wrote: > BugLink: https://bugs.launchpad.net/bugs/1875254 > > [Impact] > When audio device enters runpm D3(idle for 7 seconds) and then wakes it up > to make a sound, it flicks the screen. > This behavior could be observed while plug/remove AC cable or USB disk, > or open a terminal and press backsapce key. > > [Fix] > This issue could be fixed by this commit, it fixes the flicker during > boot-time, but it also fixes the flicker during rumtime wakeup. > 1ee48a61aa57 drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only > > Audio drivers communicate with i915 over HDA bus multiple times during > system boot-up and each of these transactions result in matching > get_power/put_power calls to i915, and depending on the platform, > a modeset change causing visible flicker. > > GLK is the only platform with minimum CDCLK significantly lower > than BCLK, and thus for GLK setting a higher CDCLK is mandatory. > > For other platforms, minimum CDCLK is close but below 2*BCLK > (e.g. on ICL, CDCLK=176.4kHz with BCLK=96kHz). Spec-wise the constraint > should be set, but in practise no communication errors have been > reported and the downside if set is the flicker observed at boot-time. > > [Test] > Verified on Dell XPS 13 9300 > > [Regression Potential] > Low, it fixes below commit which contains in ubuntu kernel and should have > been applied on ubuntu kernel, too. > Fixes: f6ec9483091f ("drm/i915: extend audio CDCLK>=2*BCLK constraint to more platforms") > > Kai Vehmanen (1): > drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only > > drivers/gpu/drm/i915/display/intel_audio.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > Applied to eoan/linux and focal/linux. Thanks, Kleber
BugLink: https://bugs.launchpad.net/bugs/1875254 [Impact] When audio device enters runpm D3(idle for 7 seconds) and then wakes it up to make a sound, it flicks the screen. This behavior could be observed while plug/remove AC cable or USB disk, or open a terminal and press backsapce key. [Fix] This issue could be fixed by this commit, it fixes the flicker during boot-time, but it also fixes the flicker during rumtime wakeup. 1ee48a61aa57 drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only Audio drivers communicate with i915 over HDA bus multiple times during system boot-up and each of these transactions result in matching get_power/put_power calls to i915, and depending on the platform, a modeset change causing visible flicker. GLK is the only platform with minimum CDCLK significantly lower than BCLK, and thus for GLK setting a higher CDCLK is mandatory. For other platforms, minimum CDCLK is close but below 2*BCLK (e.g. on ICL, CDCLK=176.4kHz with BCLK=96kHz). Spec-wise the constraint should be set, but in practise no communication errors have been reported and the downside if set is the flicker observed at boot-time. [Test] Verified on Dell XPS 13 9300 [Regression Potential] Low, it fixes below commit which contains in ubuntu kernel and should have been applied on ubuntu kernel, too. Fixes: f6ec9483091f ("drm/i915: extend audio CDCLK>=2*BCLK constraint to more platforms") Kai Vehmanen (1): drm/i915: Limit audio CDCLK>=2*BCLK constraint back to GLK only drivers/gpu/drm/i915/display/intel_audio.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)