intel_extreme: Let ports pick a pipe if required

src/add-ons/accelerants/intel_extreme/DisplayPipe.cpp

@@ -53,9 +53,14 @@ DisplayPipe::DisplayPipe(pipe_index pipeIndex)
 //	fFDILink(NULL),
 //	fPanelFitter(NULL),
 	fPipeIndex(pipeIndex),
-	fPipeBase(REGS_NORTH_PIPE_AND_PORT + pipeIndex * INTEL_DISPLAY_OFFSET),
-	fPlaneBase(REGS_NORTH_PLANE_CONTROL + pipeIndex * INTEL_PLANE_OFFSET)
+	fPipeBase(REGS_NORTH_PIPE_AND_PORT),
+	fPlaneBase(REGS_NORTH_PLANE_CONTROL)
 {
+	if (pipeIndex == INTEL_PIPE_B) {
+		fPipeBase += INTEL_DISPLAY_OFFSET;
+		fPlaneBase += INTEL_PLANE_OFFSET;
+	}
+
 	TRACE("DisplayPipe %s. Pipe Base: 0x%" B_PRIxADDR
 		" Plane Base: 0x% " B_PRIxADDR "\n", (pipeIndex == INTEL_PIPE_A)
 			? "A" : "B", fPipeBase, fPlaneBase);

src/add-ons/accelerants/intel_extreme/DisplayPipe.h

@@ -17,6 +17,7 @@
 
 
 enum pipe_index {
+	INTEL_PIPE_ANY,
 	INTEL_PIPE_A,
 	INTEL_PIPE_B
 };

src/add-ons/accelerants/intel_extreme/Ports.h

@@ -66,6 +66,9 @@ virtual	status_t					GetPLLLimits(pll_limits& limits);
 virtual status_t					SetDisplayMode(display_mode* mode,
 										uint32 colorMode) { return B_ERROR; };
 
+virtual pipe_index					PipePreference()
+										{ return INTEL_PIPE_ANY; };
+
 protected:
 		void						_SetName(const char* name);
 
@@ -120,6 +123,9 @@ virtual	bool						IsConnected();
 virtual status_t					SetDisplayMode(display_mode* mode,
 										uint32 colorMode);
 
+virtual pipe_index					PipePreference()
+										{ return INTEL_PIPE_B; };
+
 protected:
 virtual	addr_t						_DDCRegister();
 virtual addr_t						_PortRegister();

src/add-ons/accelerants/intel_extreme/accelerant.cpp

@@ -325,11 +325,20 @@ assign_pipes()
 
 	// TODO: At some point we should "group" ports to pipes with the same mode.
 	// You can drive multiple ports from a single pipe as long as the mode is
-	// the same.
+	// the same. For the moment we could get displays with the wrong pipes
+	// assigned when the count is > 1;
 
     for (uint32 i = 0; i < gInfo->port_count; i++) {
         if (gInfo->ports[i] == NULL)
             continue;
+
+		if (gInfo->ports[i]->PipePreference() != INTEL_PIPE_ANY) {
+			// Some ports *really* need to be assigned a pipe due to
+			// implementation bugs.
+			gInfo->ports[i]->AssignPipe(gInfo->ports[i]->PipePreference());
+			continue;
+		}
+
 		if (gInfo->ports[i]->IsConnected()) {
 			pipe_index currentPipe = INTEL_PIPE_A;
 			if (assigned == 1)