[Intel-gfx] [PATCH 6/9] drm/i915: PCH_NOP suspend/resume

[Ben Widawsky]

On Sun, Mar 17, 2013 at 10:28:55PM +0100, Daniel Vetter wrote:
> On Wed, Mar 13, 2013 at 11:21:05AM -0700, Ben Widawsky wrote:
> > More registers we can't write.
> > 
> > Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
> > ---
> >  drivers/gpu/drm/i915/i915_suspend.c | 57 ++++++++++++++++++++++++++-----------
> >  1 file changed, 41 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_suspend.c b/drivers/gpu/drm/i915/i915_suspend.c
> > index c1e02b0..dd5766a 100644
> > --- a/drivers/gpu/drm/i915/i915_suspend.c
> > +++ b/drivers/gpu/drm/i915/i915_suspend.c
> > @@ -333,11 +333,19 @@ int i915_save_state(struct drm_device *dev)
> >  
> >  	mutex_lock(&dev->struct_mutex);
> >  
> > -	i915_save_display(dev);
> > +	if (!HAS_PCH_NOP(dev))
> > +		i915_save_display(dev);
> 
> This here looks a bit funny - imo it's better to move this check to the
> only two places where we still touch registers in the kms case: lvds & pp
> restore.

I had something like this originally, except I also can't touch the
backlight registers (even though they're not in a bad range).

In an earlier patch you asked me to move the check up in the callchain,
and I liked that idea. It seems to me here the same logic applies, we
never care about any of the display registers. If you feel strongly
about it though, I will change it. Please correct me if I misunderstood
your request.

> 
> >  
> >  	if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
> >  		/* Interrupt state */
> > -		if (HAS_PCH_SPLIT(dev)) {
> > +		if (HAS_PCH_NOP(dev)) {
> > +			dev_priv->regfile.saveDEIER = I915_READ(DEIER);
> > +			dev_priv->regfile.saveDEIMR = I915_READ(DEIMR);
> > +			dev_priv->regfile.saveGTIER = I915_READ(GTIER);
> > +			dev_priv->regfile.saveGTIMR = I915_READ(GTIMR);
> > +			dev_priv->regfile.saveMCHBAR_RENDER_STANDBY =
> > +				I915_READ(RSTDBYCTL);
> > +		} else if (HAS_PCH_SPLIT(dev)) {
> >  			dev_priv->regfile.saveDEIER = I915_READ(DEIER);
> >  			dev_priv->regfile.saveDEIMR = I915_READ(DEIMR);
> >  			dev_priv->regfile.saveGTIER = I915_READ(GTIER);
> > @@ -361,13 +369,18 @@ int i915_save_state(struct drm_device *dev)
> >  	/* Memory Arbitration state */
> >  	dev_priv->regfile.saveMI_ARB_STATE = I915_READ(MI_ARB_STATE);
> >  
> > -	/* Scratch space */
> > -	for (i = 0; i < 16; i++) {
> > -		dev_priv->regfile.saveSWF0[i] = I915_READ(SWF00 + (i << 2));
> > -		dev_priv->regfile.saveSWF1[i] = I915_READ(SWF10 + (i << 2));
> > +	if (!HAS_PCH_NOP(dev)) {
> > +		/* Scratch space */
> > +		for (i = 0; i < 16; i++) {
> > +			dev_priv->regfile.saveSWF0[i] =
> > +				I915_READ(SWF00 + (i << 2));
> > +			dev_priv->regfile.saveSWF1[i] =
> > +				I915_READ(SWF10 + (i << 2));
> > +		}
> > +		for (i = 0; i < 3; i++)
> > +			dev_priv->regfile.saveSWF2[i] =
> > +				I915_READ(SWF30 + (i << 2));
> 
> Blergh, I hate those registers, and I have no idea where we actually need
> to restore them for kms. Can you please also add a big "XXX: Do we really
> need this for kms?" comment in the scratch space block?
> 
> >  	}
> > -	for (i = 0; i < 3; i++)
> > -		dev_priv->regfile.saveSWF2[i] = I915_READ(SWF30 + (i << 2));
> >  
> >  	mutex_unlock(&dev->struct_mutex);
> >  
> > @@ -383,11 +396,17 @@ int i915_restore_state(struct drm_device *dev)
> >  
> >  	mutex_lock(&dev->struct_mutex);
> >  
> > -	i915_restore_display(dev);
> > +	if (!HAS_PCH_NOP(dev))
> > +		i915_restore_display(dev);
> >  
> >  	if (!drm_core_check_feature(dev, DRIVER_MODESET)) {
> >  		/* Interrupt state */
> > -		if (HAS_PCH_SPLIT(dev)) {
> > +		if (HAS_PCH_NOP(dev)) {
> > +			I915_WRITE(DEIER, dev_priv->regfile.saveDEIER);
> > +			I915_WRITE(DEIMR, dev_priv->regfile.saveDEIMR);
> > +			I915_WRITE(GTIER, dev_priv->regfile.saveGTIER);
> > +			I915_WRITE(GTIMR, dev_priv->regfile.saveGTIMR);
> > +		} else if (HAS_PCH_SPLIT(dev)) {
> >  			I915_WRITE(DEIER, dev_priv->regfile.saveDEIER);
> >  			I915_WRITE(DEIMR, dev_priv->regfile.saveDEIMR);
> >  			I915_WRITE(GTIER, dev_priv->regfile.saveGTIER);
> > @@ -407,16 +426,22 @@ int i915_restore_state(struct drm_device *dev)
> >  	/* Memory arbitration state */
> >  	I915_WRITE(MI_ARB_STATE, dev_priv->regfile.saveMI_ARB_STATE | 0xffff0000);
> >  
> > -	for (i = 0; i < 16; i++) {
> > -		I915_WRITE(SWF00 + (i << 2), dev_priv->regfile.saveSWF0[i]);
> > -		I915_WRITE(SWF10 + (i << 2), dev_priv->regfile.saveSWF1[i]);
> > +	if (!HAS_PCH_NOP(dev)) {
> > +		for (i = 0; i < 16; i++) {
> > +			I915_WRITE(SWF00 + (i << 2),
> > +				   dev_priv->regfile.saveSWF0[i]);
> > +			I915_WRITE(SWF10 + (i << 2),
> > +				   dev_priv->regfile.saveSWF1[i]);
> > +		}
> > +		for (i = 0; i < 3; i++)
> > +			I915_WRITE(SWF30 + (i << 2),
> > +				   dev_priv->regfile.saveSWF2[i]);
> >  	}
> > -	for (i = 0; i < 3; i++)
> > -		I915_WRITE(SWF30 + (i << 2), dev_priv->regfile.saveSWF2[i]);
> >  
> >  	mutex_unlock(&dev->struct_mutex);
> >  
> > -	intel_i2c_reset(dev);
> > +	if (!HAS_PCH_NOP(dev))
> > +		intel_i2c_reset(dev);
> >  
> >  	return 0;
> >  }
> > -- 
> > 1.8.1.5
> > 
> > _______________________________________________
> > 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

-- 
Ben Widawsky, Intel Open Source Technology Center