Disable RPS by setting RP_CONTROL to 0, remembering its earlier value. Then adjust the thresholds before re-enabling RP_CONTROL. Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/gpu/drm/i915/intel_pm.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index d37e95b3525d..e5cfa0377367 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -4804,6 +4804,7 @@ static void gen6_set_rps_thresholds(struct drm_i915_private *dev_priv, u8 val) int new_power; u32 threshold_up = 0, threshold_down = 0; /* in % */ u32 ei_up = 0, ei_down = 0; + u32 rp_control; new_power = dev_priv->rps.power; switch (dev_priv->rps.power) { @@ -4872,6 +4873,12 @@ static void gen6_set_rps_thresholds(struct drm_i915_private *dev_priv, u8 val) spin_lock_irq(&dev_priv->uncore.lock); intel_uncore_forcewake_get__locked(dev_priv, FORCEWAKE_ALL); + /* Stop RPS before changing thresholds */ + rp_control = I915_READ_FW(GEN6_RP_CONTROL); + I915_WRITE_FW(GEN6_RP_CONTROL, 0); + POSTING_READ_FW(GEN6_RP_CONTROL); + + /* Update thresholds and evaluation intervals */ I915_WRITE_FW(GEN6_RP_UP_EI, GT_INTERVAL_FROM_US(dev_priv, ei_up)); I915_WRITE_FW(GEN6_RP_UP_THRESHOLD, @@ -4885,8 +4892,7 @@ static void gen6_set_rps_thresholds(struct drm_i915_private *dev_priv, u8 val) ei_down * threshold_down / 100)); /* Restart RPS to reload the thresholds */ - I915_WRITE_FW(GEN6_RP_CONTROL, - I915_READ_FW(GEN6_RP_CONTROL) | GEN6_RP_ENABLE); + I915_WRITE_FW(GEN6_RP_CONTROL, rp_control | GEN6_RP_ENABLE); intel_uncore_forcewake_put__locked(dev_priv, FORCEWAKE_ALL); spin_unlock_irq(&dev_priv->uncore.lock); -- 2.11.0