[PATCH] drm/i915/dsi: Do not clear DPOUNIT_CLOCK_GATE_DISABLE from vlv_init_display_clock_gating
On Fri, Dec 02, 2016 at 02:27:43PM +0100, Hans de Goede wrote:
> Hi,
>
> On 02-12-16 13:40, Ville Syrjälä wrote:
> > On Thu, Dec 01, 2016 at 04:39:57PM +0100, Hans de Goede wrote:
> >> On my Cherrytrail CUBE iwork8 Air tablet PIPE-A would get stuck on loading
> >> i915 at boot 1 out of every 3 boots, resulting in a non functional LCD.
> >> Once the i915 driver has successfully loaded, the panel can be disabled /
> >> enabled without hitting this issue.
> >>
> >> The getting stuck is caused by vlv_init_display_clock_gating() clearing
> >> the DPOUNIT_CLOCK_GATE_DISABLE bit in DSPCLK_GATE_D when called from
> >> chv_pipe_power_well_ops.enable() on driver load, while PIPE-A is enabled
> >> driving the DSI LCD by the BIOS.
> >>
> >> Clearing this bit while DSI is in use is a known issue and
> >> intel_dsi_pre_enable() / intel_dsi_post_disable() already set / clear it
> >> as appropriate.
> >>
> >> This commit modifies vlv_init_display_clock_gating() to leave the
> >> DPOUNIT_CLOCK_GATE_DISABLE bit alone fixing PIPE-A getting stuck.
> >>
> >> BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=97330
> >> Cc: stable at vger.kernel.org
> >> Signed-off-by: Hans de Goede
> >> ---
> >> drivers/gpu/drm/i915/intel_runtime_pm.c | 13 -
> >> 1 file changed, 12 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
> >> b/drivers/gpu/drm/i915/intel_runtime_pm.c
> >> index 356c662..b5ce7cb 100644
> >> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
> >> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
> >> @@ -1039,7 +1039,18 @@ static bool vlv_power_well_enabled(struct
> >> drm_i915_private *dev_priv,
> >>
> >> static void vlv_init_display_clock_gating(struct drm_i915_private
> >> *dev_priv)
> >> {
> >> - I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE);
> >> + u32 val;
> >> +
> >> + /*
> >> + * When on driver load, PIPE A may be active and driving a DSI display.
> >> + * Preserve DPOUNIT_CLOCK_GATE_DISABLE to avoid PIPE A getting stuck
> >> + * (and never recovering) in this case. intel_dsi_post_disable() will
> >> + * clear it when we turn off the display.
> >
> > Why are you talking only about pipe A here?
>
> Because that is the pipe which was getting stuck on my tablet. I see that
> the comment for the same workaround in intel_dsi.c just says:
> " Disable DPOunit clock gating, can stall pipe" so I guess I should
> update the comment s/PIPE A/pipe(s)/. Any other remarks before I send a v2 ?
Nope. With that this is
Reviewed-by: Ville Syrjälä
>
> Regards,
>
> Hans
>
>
>
> >
> >> + */
> >> + val = I915_READ(DSPCLK_GATE_D);
> >> + val &= DPOUNIT_CLOCK_GATE_DISABLE;
> >> + val |= VRHUNIT_CLOCK_GATE_DISABLE;
> >> + I915_WRITE(DSPCLK_GATE_D, val);
> >>
> >>/*
> >> * Disable trickle feed and enable pnd deadline calculation
> >> --
> >> 2.9.3
> >>
> >> ___
> >> dri-devel mailing list
> >> dri-devel at lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/dri-devel
> >
--
Ville Syrjälä
Intel OTC
[PATCH] drm/i915/dsi: Do not clear DPOUNIT_CLOCK_GATE_DISABLE from vlv_init_display_clock_gating
On Thu, Dec 01, 2016 at 04:39:57PM +0100, Hans de Goede wrote:
> On my Cherrytrail CUBE iwork8 Air tablet PIPE-A would get stuck on loading
> i915 at boot 1 out of every 3 boots, resulting in a non functional LCD.
> Once the i915 driver has successfully loaded, the panel can be disabled /
> enabled without hitting this issue.
>
> The getting stuck is caused by vlv_init_display_clock_gating() clearing
> the DPOUNIT_CLOCK_GATE_DISABLE bit in DSPCLK_GATE_D when called from
> chv_pipe_power_well_ops.enable() on driver load, while PIPE-A is enabled
> driving the DSI LCD by the BIOS.
>
> Clearing this bit while DSI is in use is a known issue and
> intel_dsi_pre_enable() / intel_dsi_post_disable() already set / clear it
> as appropriate.
>
> This commit modifies vlv_init_display_clock_gating() to leave the
> DPOUNIT_CLOCK_GATE_DISABLE bit alone fixing PIPE-A getting stuck.
>
> BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=97330
> Cc: stable at vger.kernel.org
> Signed-off-by: Hans de Goede
> ---
> drivers/gpu/drm/i915/intel_runtime_pm.c | 13 -
> 1 file changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
> b/drivers/gpu/drm/i915/intel_runtime_pm.c
> index 356c662..b5ce7cb 100644
> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
> @@ -1039,7 +1039,18 @@ static bool vlv_power_well_enabled(struct
> drm_i915_private *dev_priv,
>
> static void vlv_init_display_clock_gating(struct drm_i915_private *dev_priv)
> {
> - I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE);
> + u32 val;
> +
> + /*
> + * When on driver load, PIPE A may be active and driving a DSI display.
> + * Preserve DPOUNIT_CLOCK_GATE_DISABLE to avoid PIPE A getting stuck
> + * (and never recovering) in this case. intel_dsi_post_disable() will
> + * clear it when we turn off the display.
Why are you talking only about pipe A here?
> + */
> + val = I915_READ(DSPCLK_GATE_D);
> + val &= DPOUNIT_CLOCK_GATE_DISABLE;
> + val |= VRHUNIT_CLOCK_GATE_DISABLE;
> + I915_WRITE(DSPCLK_GATE_D, val);
>
> /*
>* Disable trickle feed and enable pnd deadline calculation
> --
> 2.9.3
>
> ___
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
--
Ville Syrjälä
Intel OTC
[PATCH] drm/i915/dsi: Do not clear DPOUNIT_CLOCK_GATE_DISABLE from vlv_init_display_clock_gating
Hi,
On 02-12-16 13:40, Ville Syrjälä wrote:
> On Thu, Dec 01, 2016 at 04:39:57PM +0100, Hans de Goede wrote:
>> On my Cherrytrail CUBE iwork8 Air tablet PIPE-A would get stuck on loading
>> i915 at boot 1 out of every 3 boots, resulting in a non functional LCD.
>> Once the i915 driver has successfully loaded, the panel can be disabled /
>> enabled without hitting this issue.
>>
>> The getting stuck is caused by vlv_init_display_clock_gating() clearing
>> the DPOUNIT_CLOCK_GATE_DISABLE bit in DSPCLK_GATE_D when called from
>> chv_pipe_power_well_ops.enable() on driver load, while PIPE-A is enabled
>> driving the DSI LCD by the BIOS.
>>
>> Clearing this bit while DSI is in use is a known issue and
>> intel_dsi_pre_enable() / intel_dsi_post_disable() already set / clear it
>> as appropriate.
>>
>> This commit modifies vlv_init_display_clock_gating() to leave the
>> DPOUNIT_CLOCK_GATE_DISABLE bit alone fixing PIPE-A getting stuck.
>>
>> BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=97330
>> Cc: stable at vger.kernel.org
>> Signed-off-by: Hans de Goede
>> ---
>> drivers/gpu/drm/i915/intel_runtime_pm.c | 13 -
>> 1 file changed, 12 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
>> b/drivers/gpu/drm/i915/intel_runtime_pm.c
>> index 356c662..b5ce7cb 100644
>> --- a/drivers/gpu/drm/i915/intel_runtime_pm.c
>> +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
>> @@ -1039,7 +1039,18 @@ static bool vlv_power_well_enabled(struct
>> drm_i915_private *dev_priv,
>>
>> static void vlv_init_display_clock_gating(struct drm_i915_private *dev_priv)
>> {
>> -I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE);
>> +u32 val;
>> +
>> +/*
>> + * When on driver load, PIPE A may be active and driving a DSI display.
>> + * Preserve DPOUNIT_CLOCK_GATE_DISABLE to avoid PIPE A getting stuck
>> + * (and never recovering) in this case. intel_dsi_post_disable() will
>> + * clear it when we turn off the display.
>
> Why are you talking only about pipe A here?
Because that is the pipe which was getting stuck on my tablet. I see that
the comment for the same workaround in intel_dsi.c just says:
" Disable DPOunit clock gating, can stall pipe" so I guess I should
update the comment s/PIPE A/pipe(s)/. Any other remarks before I send a v2 ?
Regards,
Hans
>
>> + */
>> +val = I915_READ(DSPCLK_GATE_D);
>> +val &= DPOUNIT_CLOCK_GATE_DISABLE;
>> +val |= VRHUNIT_CLOCK_GATE_DISABLE;
>> +I915_WRITE(DSPCLK_GATE_D, val);
>>
>> /*
>> * Disable trickle feed and enable pnd deadline calculation
>> --
>> 2.9.3
>>
>> ___
>> dri-devel mailing list
>> dri-devel at lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>
[PATCH] drm/i915/dsi: Do not clear DPOUNIT_CLOCK_GATE_DISABLE from vlv_init_display_clock_gating
On my Cherrytrail CUBE iwork8 Air tablet PIPE-A would get stuck on loading
i915 at boot 1 out of every 3 boots, resulting in a non functional LCD.
Once the i915 driver has successfully loaded, the panel can be disabled /
enabled without hitting this issue.
The getting stuck is caused by vlv_init_display_clock_gating() clearing
the DPOUNIT_CLOCK_GATE_DISABLE bit in DSPCLK_GATE_D when called from
chv_pipe_power_well_ops.enable() on driver load, while PIPE-A is enabled
driving the DSI LCD by the BIOS.
Clearing this bit while DSI is in use is a known issue and
intel_dsi_pre_enable() / intel_dsi_post_disable() already set / clear it
as appropriate.
This commit modifies vlv_init_display_clock_gating() to leave the
DPOUNIT_CLOCK_GATE_DISABLE bit alone fixing PIPE-A getting stuck.
BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=97330
Cc: stable at vger.kernel.org
Signed-off-by: Hans de Goede
---
drivers/gpu/drm/i915/intel_runtime_pm.c | 13 -
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 356c662..b5ce7cb 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -1039,7 +1039,18 @@ static bool vlv_power_well_enabled(struct
drm_i915_private *dev_priv,
static void vlv_init_display_clock_gating(struct drm_i915_private *dev_priv)
{
- I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE);
+ u32 val;
+
+ /*
+* When on driver load, PIPE A may be active and driving a DSI display.
+* Preserve DPOUNIT_CLOCK_GATE_DISABLE to avoid PIPE A getting stuck
+* (and never recovering) in this case. intel_dsi_post_disable() will
+* clear it when we turn off the display.
+*/
+ val = I915_READ(DSPCLK_GATE_D);
+ val &= DPOUNIT_CLOCK_GATE_DISABLE;
+ val |= VRHUNIT_CLOCK_GATE_DISABLE;
+ I915_WRITE(DSPCLK_GATE_D, val);
/*
* Disable trickle feed and enable pnd deadline calculation
--
2.9.3
