[Intel-gfx] [PATCH] drm/i915/vlv: T12 eDP panel timing enforcement during reboot

[Daniel Vetter]

On Thu, Jul 03, 2014 at 11:44:34PM +0300, Jani Nikula wrote:
> On Thu, 03 Jul 2014, Clint Taylor <clinton.a.taylor at intel.com> wrote:
> > On 07/02/2014 01:35 AM, Jani Nikula wrote:
> >> From: Clint Taylor <Clinton.A.Taylor at intel.com>
> >>
> >> The panel power sequencer on vlv doesn't appear to accept changes to its
> >> T12 power down duration during warm reboots. This change forces a delay
> >> for warm reboots to the T12 panel timing as defined in the VBT table for
> >> the connected panel.
> >>
> >> Ver2: removed redundant pr_crit(), commented magic value for pp_div_reg
> >>
> >> Ver3: moved SYS_RESTART check earlier, new name for pp_div.
> >>
> >> Ver4: Minor issue changes
> >>
> >> Signed-off-by: Clint Taylor <clinton.a.taylor at intel.com>
> >> [Jani: rebased on current -nightly.]
> >> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> >>
> >> ---
> >>
> >> I ended up doing the rebase myself, but I'd like to have a quick review
> >> before pushing.
> >
> > Quick review complete. Everything appears OK.
> 
> See Paulo's review; want to take over?

Imo this is -fixes material, but it looks like it's not yet complete. I'll
wait for a resend safe when someone yells at me that the current patch is
ok-ish (maybe just needs a pimped commit message or a comment somewhere to
address Paulo's concerns).
-Daniel
> 
> Jani.
> 
> 
> >
> >
> >>
> >> Thanks,
> >> Jani.
> >> ---
> >>   drivers/gpu/drm/i915/intel_dp.c  | 40 ++++++++++++++++++++++++++++++++++++++++
> >>   drivers/gpu/drm/i915/intel_drv.h |  2 ++
> >>   2 files changed, 42 insertions(+)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> >> index b5ec48913b47..f0d23c435cf6 100644
> >> --- a/drivers/gpu/drm/i915/intel_dp.c
> >> +++ b/drivers/gpu/drm/i915/intel_dp.c
> >> @@ -28,6 +28,8 @@
> >>   #include <linux/i2c.h>
> >>   #include <linux/slab.h>
> >>   #include <linux/export.h>
> >> +#include <linux/notifier.h>
> >> +#include <linux/reboot.h>
> >>   #include <drm/drmP.h>
> >>   #include <drm/drm_crtc.h>
> >>   #include <drm/drm_crtc_helper.h>
> >> @@ -336,6 +338,36 @@ static u32 _pp_stat_reg(struct intel_dp *intel_dp)
> >>   		return VLV_PIPE_PP_STATUS(vlv_power_sequencer_pipe(intel_dp));
> >>   }
> >>
> >> +/* Reboot notifier handler to shutdown panel power to guarantee T12 timing */
> >> +static int edp_notify_handler(struct notifier_block *this, unsigned long code,
> >> +			      void *unused)
> >> +{
> >> +	struct intel_dp *intel_dp = container_of(this, typeof(* intel_dp),
> >> +						 edp_notifier);
> >> +	struct drm_device *dev = intel_dp_to_dev(intel_dp);
> >> +	struct drm_i915_private *dev_priv = dev->dev_private;
> >> +	u32 pp_div;
> >> +	u32 pp_ctrl_reg, pp_div_reg;
> >> +	enum pipe pipe = vlv_power_sequencer_pipe(intel_dp);
> >> +
> >> +	if (!is_edp(intel_dp) || code != SYS_RESTART)
> >> +		return 0;
> >> +
> >> +	if (IS_VALLEYVIEW(dev)) {
> >> +		pp_ctrl_reg = VLV_PIPE_PP_CONTROL(pipe);
> >> +		pp_div_reg  = VLV_PIPE_PP_DIVISOR(pipe);
> >> +		pp_div = I915_READ(VLV_PIPE_PP_DIVISOR(pipe));
> >> +		pp_div &= PP_REFERENCE_DIVIDER_MASK;
> >> +
> >> +		/* 0x1F write to PP_DIV_REG sets max cycle delay */
> >> +		I915_WRITE(pp_div_reg, pp_div | 0x1F);
> >> +		I915_WRITE(pp_ctrl_reg, PANEL_UNLOCK_REGS | PANEL_POWER_OFF);
> >> +		msleep(intel_dp->panel_power_cycle_delay);
> >> +	}
> >> +
> >> +	return 0;
> >> +}
> >> +
> >>   static bool edp_have_panel_power(struct intel_dp *intel_dp)
> >>   {
> >>   	struct drm_device *dev = intel_dp_to_dev(intel_dp);
> >> @@ -3785,6 +3817,10 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder)
> >>   		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
> >>   		edp_panel_vdd_off_sync(intel_dp);
> >>   		drm_modeset_unlock(&dev->mode_config.connection_mutex);
> >> +		if (intel_dp->edp_notifier.notifier_call) {
> >> +			unregister_reboot_notifier(&intel_dp->edp_notifier);
> >> +			intel_dp->edp_notifier.notifier_call = NULL;
> >> +		}
> >>   	}
> >>   	kfree(intel_dig_port);
> >>   }
> >> @@ -4353,6 +4389,10 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
> >>   	if (is_edp(intel_dp)) {
> >>   		intel_dp_init_panel_power_timestamps(intel_dp);
> >>   		intel_dp_init_panel_power_sequencer(dev, intel_dp, &power_seq);
> >> +		if (IS_VALLEYVIEW(dev)) {
> >> +			intel_dp->edp_notifier.notifier_call = edp_notify_handler;
> >> +			register_reboot_notifier(&intel_dp->edp_notifier);
> >> +		}
> >>   	}
> >>
> >>   	intel_dp_aux_init(intel_dp, intel_connector);
> >> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> >> index 5f7c7bd94d90..87d1715db21d 100644
> >> --- a/drivers/gpu/drm/i915/intel_drv.h
> >> +++ b/drivers/gpu/drm/i915/intel_drv.h
> >> @@ -541,6 +541,8 @@ struct intel_dp {
> >>   	unsigned long last_power_cycle;
> >>   	unsigned long last_power_on;
> >>   	unsigned long last_backlight_off;
> >> +	struct notifier_block edp_notifier;
> >> +
> >>   	bool use_tps3;
> >>   	struct intel_connector *attached_connector;
> >>
> >>
> >
> 
> -- 
> 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

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch