On Baytrail, we manually calculate busyness over the evaluation interval
to avoid issues with miscaluations with RC6 enabled. However, it turns
out that the DOWN_EI interrupt generator is completely bust - it
operates in two modes, continuous or never. Neither of which are
conducive to good behaviour. Stop unmask the DOWN_EI interrupt and just
compute everything from the UP_EI which does seem to correspond to the
desired interval.
Fixes: 43cf3bf084ba ("drm/i915: Improved w/a for rps on Baytrail")
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.1+
---
drivers/gpu/drm/i915/i915_drv.h | 2 +-
drivers/gpu/drm/i915/i915_irq.c | 28 +++++++++-------------------
drivers/gpu/drm/i915/intel_pm.c | 2 +-
3 files changed, 11 insertions(+), 21 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 4e7046df1b5e..8190ab500e03 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1359,7 +1359,7 @@ struct intel_gen6_power_mgmt {
unsigned boosts;
/* manual wa residency calculations */
- struct intel_rps_ei up_ei, down_ei;
+ struct intel_rps_ei ei;
/*
* Protects RPS/RC6 register access and PCU communication.
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 57fa1bf78a85..09f6a190d363 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -1048,10 +1048,10 @@ static void vlv_c0_read(struct drm_i915_private *dev_priv,
}
static bool vlv_c0_above(struct drm_i915_private *dev_priv,
- const struct intel_rps_ei *old,
const struct intel_rps_ei *now,
int threshold)
{
+ const struct intel_rps_ei *old = &dev_priv->rps.ei;
u64 time, c0;
unsigned int mul = 100;
@@ -1077,8 +1077,7 @@ static bool vlv_c0_above(struct drm_i915_private *dev_priv,
void gen6_rps_reset_ei(struct drm_i915_private *dev_priv)
{
- vlv_c0_read(dev_priv, &dev_priv->rps.down_ei);
- dev_priv->rps.up_ei = dev_priv->rps.down_ei;
+ memset(&dev_priv->rps.ei, 0, sizeof(dev_priv->rps.ei));
}
static u32 vlv_wa_c0_ei(struct drm_i915_private *dev_priv, u32 pm_iir)
@@ -1086,28 +1085,19 @@ static u32 vlv_wa_c0_ei(struct drm_i915_private *dev_priv, u32 pm_iir)
struct intel_rps_ei now;
u32 events = 0;
- if ((pm_iir & (GEN6_PM_RP_DOWN_EI_EXPIRED | GEN6_PM_RP_UP_EI_EXPIRED)) == 0)
+ if ((pm_iir & GEN6_PM_RP_UP_EI_EXPIRED) == 0)
return 0;
vlv_c0_read(dev_priv, &now);
if (now.cz_clock == 0)
return 0;
- if (pm_iir & GEN6_PM_RP_DOWN_EI_EXPIRED) {
- if (!vlv_c0_above(dev_priv,
- &dev_priv->rps.down_ei, &now,
- dev_priv->rps.down_threshold))
- events |= GEN6_PM_RP_DOWN_THRESHOLD;
- dev_priv->rps.down_ei = now;
- }
+ if (vlv_c0_above(dev_priv, &now, dev_priv->rps.up_threshold))
+ events |= GEN6_PM_RP_UP_THRESHOLD;
+ else if (!vlv_c0_above(dev_priv, &now, dev_priv->rps.down_threshold))
+ events |= GEN6_PM_RP_DOWN_THRESHOLD;
- if (pm_iir & GEN6_PM_RP_UP_EI_EXPIRED) {
- if (vlv_c0_above(dev_priv,
- &dev_priv->rps.up_ei, &now,
- dev_priv->rps.up_threshold))
- events |= GEN6_PM_RP_UP_THRESHOLD;
- dev_priv->rps.up_ei = now;
- }
+ dev_priv->rps.ei = now;
return events;
}
@@ -4248,7 +4238,7 @@ void intel_irq_init(struct drm_i915_private *dev_priv)
/* Let's track the enabled rps events */
if (IS_VALLEYVIEW(dev_priv))
/* WaGsvRC0ResidencyMethod:vlv */
- dev_priv->pm_rps_events = GEN6_PM_RP_DOWN_EI_EXPIRED | GEN6_PM_RP_UP_EI_EXPIRED;
+ dev_priv->pm_rps_events = GEN6_PM_RP_UP_EI_EXPIRED;
else
dev_priv->pm_rps_events = GEN6_PM_RPS_EVENTS;
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 169c4908ad5b..92cedd97a878 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5010,7 +5010,7 @@ void gen6_rps_busy(struct drm_i915_private *dev_priv)
if (dev_priv->rps.enabled) {
u8 freq;
- if (dev_priv->pm_rps_events & (GEN6_PM_RP_DOWN_EI_EXPIRED | GEN6_PM_RP_UP_EI_EXPIRED))
+ if (dev_priv->pm_rps_events & GEN6_PM_RP_UP_EI_EXPIRED)
gen6_rps_reset_ei(dev_priv);
I915_WRITE(GEN6_PMINTRMSK,
gen6_rps_pm_mask(dev_priv, dev_priv->rps.cur_freq));
--
2.11.0