drm/i915: clear DPLL reg when disabling i9xx dplls
Toghether with the hw state readout this should catch cases where we
don't properly updated the pll state (either in sw or hw). At least
for the shared dpll code the equivalent tricke helped a lot in
catching bugs.
Also rename the function prefix, it's not a generic piece of
infrastructure.
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3d1c97a..ae3dc5d 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1406,7 +1406,7 @@
}
/**
- * intel_disable_pll - disable a PLL
+ * i9xx_disable_pll - disable a PLL
* @dev_priv: i915 private structure
* @pipe: pipe PLL to disable
*
@@ -1414,11 +1414,8 @@
*
* Note! This is for pre-ILK only.
*/
-static void intel_disable_pll(struct drm_i915_private *dev_priv, enum pipe pipe)
+static void i9xx_disable_pll(struct drm_i915_private *dev_priv, enum pipe pipe)
{
- int reg;
- u32 val;
-
/* Don't disable pipe A or pipe A PLLs if needed */
if (pipe == PIPE_A && (dev_priv->quirks & QUIRK_PIPEA_FORCE))
return;
@@ -1426,11 +1423,8 @@
/* Make sure the pipe isn't still relying on us */
assert_pipe_disabled(dev_priv, pipe);
- reg = DPLL(pipe);
- val = I915_READ(reg);
- val &= ~DPLL_VCO_ENABLE;
- I915_WRITE(reg, val);
- POSTING_READ(reg);
+ I915_WRITE(DPLL(pipe), 0);
+ POSTING_READ(DPLL(pipe));
}
void vlv_wait_port_ready(struct drm_i915_private *dev_priv, int port)
@@ -3782,7 +3776,7 @@
if (encoder->post_disable)
encoder->post_disable(encoder);
- intel_disable_pll(dev_priv, pipe);
+ i9xx_disable_pll(dev_priv, pipe);
intel_crtc->active = false;
intel_update_fbc(dev);