drm/i915: Fix computation of last_adjustment for RPS autotuning

The issue is that by computing the last_adj value after applying the
clamping, we can end up with a bogus value for feeding into the next RPS
autotuning step.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Deepak S <deepak.s@linux.intel.com>
Reviewed-by: Deepak S <deepak.s@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Chris Wilson 2015-04-07 16:20:29 +01:00 committed by Daniel Vetter
parent 8fb55197e6
commit edcf284bfe

View File

@ -1095,21 +1095,20 @@ static void gen6_pm_rps_work(struct work_struct *work)
pm_iir |= vlv_wa_c0_ei(dev_priv, pm_iir);
adj = dev_priv->rps.last_adj;
new_delay = dev_priv->rps.cur_freq;
if (pm_iir & GEN6_PM_RP_UP_THRESHOLD) {
if (adj > 0)
adj *= 2;
else {
/* CHV needs even encode values */
adj = IS_CHERRYVIEW(dev_priv->dev) ? 2 : 1;
}
new_delay = dev_priv->rps.cur_freq + adj;
else /* CHV needs even encode values */
adj = IS_CHERRYVIEW(dev_priv) ? 2 : 1;
/*
* For better performance, jump directly
* to RPe if we're below it.
*/
if (new_delay < dev_priv->rps.efficient_freq)
if (new_delay < dev_priv->rps.efficient_freq - adj) {
new_delay = dev_priv->rps.efficient_freq;
adj = 0;
}
} else if (pm_iir & GEN6_PM_RP_DOWN_TIMEOUT) {
if (dev_priv->rps.cur_freq > dev_priv->rps.efficient_freq)
new_delay = dev_priv->rps.efficient_freq;
@ -1119,24 +1118,22 @@ static void gen6_pm_rps_work(struct work_struct *work)
} else if (pm_iir & GEN6_PM_RP_DOWN_THRESHOLD) {
if (adj < 0)
adj *= 2;
else {
/* CHV needs even encode values */
adj = IS_CHERRYVIEW(dev_priv->dev) ? -2 : -1;
}
new_delay = dev_priv->rps.cur_freq + adj;
else /* CHV needs even encode values */
adj = IS_CHERRYVIEW(dev_priv) ? -2 : -1;
} else { /* unknown event */
new_delay = dev_priv->rps.cur_freq;
adj = 0;
}
dev_priv->rps.last_adj = adj;
/* sysfs frequency interfaces may have snuck in while servicing the
* interrupt
*/
new_delay += adj;
new_delay = clamp_t(int, new_delay,
dev_priv->rps.min_freq_softlimit,
dev_priv->rps.max_freq_softlimit);
dev_priv->rps.last_adj = new_delay - dev_priv->rps.cur_freq;
intel_set_rps(dev_priv->dev, new_delay);
mutex_unlock(&dev_priv->rps.hw_lock);