drm/i915: handle DDI-related assertions

Prevent bogus asserts on DDI-related paths.

Longer explanation from Eugeni by mail:

"For the asserts there are 3 paths where we hit them:
- in assert_fdi_tx (we don't have the FDI_TX_CTL anymore, backup plan
  DDI_FUNC_CTL is used instead)
- in assert_fdi_tx_pll_enabled (we have the combination of iCLKIP and
  DDI_FUNC_CTL, plus PORT_CLK_SEL and PIPE_CLK_SEL now to make things
  work). We could use an assert here indeed - if we configure port to
  use one clock, and pipe to use another, everything hangs. Right now,
  we configure all of them in one place only; but yes, when DP code
  lands it will get more funky.
- and in ironlake_fdi_pll_enable. I reuse part of this function (to
  configure the TU sizes), but as in the 1st case, FDI_TX_CTL is gone
  so I just ignore it here."

Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
[danvet: Pasted Eugeni's explanation into the commit message.]
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 c8f85de137e307c2764ebb4f120eb842286fa9f8..7d59d0e852f8739ba94776caba180fa352a51ea9 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -953,9 +953,16 @@ static void assert_fdi_tx(struct drm_i915_private *dev_priv,
        u32 val;
        bool cur_state;
 
-       reg = FDI_TX_CTL(pipe);
-       val = I915_READ(reg);
-       cur_state = !!(val & FDI_TX_ENABLE);
+       if (IS_HASWELL(dev_priv->dev)) {
+               /* On Haswell, DDI is used instead of FDI_TX_CTL */
+               reg = DDI_FUNC_CTL(pipe);
+               val = I915_READ(reg);
+               cur_state = !!(val & PIPE_DDI_FUNC_ENABLE);
+       } else {
+               reg = FDI_TX_CTL(pipe);
+               val = I915_READ(reg);
+               cur_state = !!(val & FDI_TX_ENABLE);
+       }
        WARN(cur_state != state,
             "FDI TX state assertion failure (expected %s, current %s)\n",
             state_string(state), state_string(cur_state));
@@ -990,6 +997,10 @@ static void assert_fdi_tx_pll_enabled(struct drm_i915_private *dev_priv,
        if (dev_priv->info->gen == 5)
                return;
 
+       /* On Haswell, DDI ports are responsible for the FDI PLL setup */
+       if (IS_HASWELL(dev_priv->dev))
+               return;
+
        reg = FDI_TX_CTL(pipe);
        val = I915_READ(reg);
        WARN(!(val & FDI_TX_PLL_ENABLE), "FDI TX PLL assertion failure, should be active but is disabled\n");
@@ -2514,14 +2525,18 @@ static void ironlake_fdi_pll_enable(struct drm_crtc *crtc)
        POSTING_READ(reg);
        udelay(200);
 
-       /* Enable CPU FDI TX PLL, always on for Ironlake */
-       reg = FDI_TX_CTL(pipe);
-       temp = I915_READ(reg);
-       if ((temp & FDI_TX_PLL_ENABLE) == 0) {
-               I915_WRITE(reg, temp | FDI_TX_PLL_ENABLE);
+       /* On Haswell, the PLL configuration for ports and pipes is handled
+        * separately, as part of DDI setup */
+       if (!IS_HASWELL(dev)) {
+               /* Enable CPU FDI TX PLL, always on for Ironlake */
+               reg = FDI_TX_CTL(pipe);
+               temp = I915_READ(reg);
+               if ((temp & FDI_TX_PLL_ENABLE) == 0) {
+                       I915_WRITE(reg, temp | FDI_TX_PLL_ENABLE);
 
-               POSTING_READ(reg);
-               udelay(100);
+                       POSTING_READ(reg);
+                       udelay(100);
+               }
        }
 }