@@ -919,7 +919,6 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
intel_dp->DP |= intel_crtc->pipe << 29;
/* don't miss out required setting for eDP */
- intel_dp->DP |= DP_PLL_ENABLE;
if (adjusted_mode->clock < 200000)
intel_dp->DP |= DP_PLL_FREQ_160MHZ;
else
@@ -941,7 +940,6 @@ intel_dp_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
if (is_cpu_edp(intel_dp)) {
/* don't miss out required setting for eDP */
- intel_dp->DP |= DP_PLL_ENABLE;
if (adjusted_mode->clock < 200000)
intel_dp->DP |= DP_PLL_FREQ_160MHZ;
else
@@ -1220,8 +1218,11 @@ static void ironlake_edp_pll_on(struct intel_dp *intel_dp)
DRM_DEBUG_KMS("\n");
dpa_ctl = I915_READ(DP_A);
- dpa_ctl |= DP_PLL_ENABLE;
- I915_WRITE(DP_A, dpa_ctl);
+ WARN(dpa_ctl & DP_PLL_ENABLE, "dp pll on, should be off\n");
+ WARN(dpa_ctl & DP_PORT_EN, "dp port still on, should be off\n");
+
+ intel_dp->DP |= DP_PLL_ENABLE;
+ I915_WRITE(DP_A, intel_dp->DP);
POSTING_READ(DP_A);
udelay(200);
}
@@ -1237,6 +1238,13 @@ static void ironlake_edp_pll_off(struct intel_dp *intel_dp)
to_intel_crtc(crtc)->pipe);
dpa_ctl = I915_READ(DP_A);
+ WARN((dpa_ctl & DP_PLL_ENABLE) == 0,
+ "dp pll off, should be on\n");
+ WARN(dpa_ctl & DP_PORT_EN, "dp port still on, should be off\n");
+
+ /* We can't rely on the value tracked for the DP register in
+ * intel_dp->DP because link_down must not change that (otherwise link
+ * re-training will fail. */
dpa_ctl &= ~DP_PLL_ENABLE;
I915_WRITE(DP_A, dpa_ctl);
POSTING_READ(DP_A);
@@ -1919,13 +1927,6 @@ intel_dp_link_down(struct intel_dp *intel_dp)
DRM_DEBUG_KMS("\n");
- if (is_edp(intel_dp)) {
- DP &= ~DP_PLL_ENABLE;
- I915_WRITE(intel_dp->output_reg, DP);
- POSTING_READ(intel_dp->output_reg);
- udelay(100);
- }
-
if (HAS_PCH_CPT(dev) && (IS_GEN7(dev) || !is_cpu_edp(intel_dp))) {
DP &= ~DP_LINK_TRAIN_MASK_CPT;
I915_WRITE(intel_dp->output_reg, DP | DP_LINK_TRAIN_PAT_IDLE_CPT);
@@ -2473,6 +2474,8 @@ intel_dp_init(struct drm_device *dev, int output_reg)
return;
intel_dp->output_reg = output_reg;
+ /* Preserve the current hw state. */
+ intel_dp->DP = I915_READ(intel_dp->output_reg);
intel_connector = kzalloc(sizeof(struct intel_connector), GFP_KERNEL);
if (!intel_connector) {
With the previous patch to clean up where exactly these two functions are getting called, this patch can tackle the enable/disable code itself: - WARN if the port enable bit is in the wrong state or if the edp pll bit is in the wrong state, just for paranoia's sake. - Don't disable the edp pll harder in the modeset functions just for fun. - Don't set the edp pll enable flag in intel_dp->DP in modeset, do that while changing the actual hw state. We do the same with the actual port enable bit, so this is a bit more consistent. - Track the current DP register value when setting things up and add some comments how intel_dp->DP is used in the disable code. Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch> --- drivers/gpu/drm/i915/intel_dp.c | 25 ++++++++++++++----------- 1 files changed, 14 insertions(+), 11 deletions(-)