ppc4xx: Rework 440GX UIC handling

This patch reworks the 440GX interrupt handling so that the common 4xx
code can be used. The 440GX is an exception to all other 4xx variants
by having the cascading interrupt vectors not on UIC0 but on a special
UIC named UICB0 (UIC Base 0). With this patch now, U-Boot references
the 440GX UICB0 when UIC0 is selected. And the common 4xx interrupt
handling is simpler without any 440GX special cases.

Also some additional cleanup to cpu/ppc4xx/interrupt.c is done.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/amcc/ocotea/ocotea.c b/board/amcc/ocotea/ocotea.c
index eea1e1e..4d1d093 100644
--- a/board/amcc/ocotea/ocotea.c
+++ b/board/amcc/ocotea/ocotea.c
@@ -147,36 +147,48 @@
 	/*--------------------------------------------------------------------
 	 * Setup the interrupt controller polarities, triggers, etc.
 	 *-------------------------------------------------------------------*/
-	mtdcr (uic0sr, 0xffffffff);	/* clear all */
-	mtdcr (uic0er, 0x00000000);	/* disable all */
-	mtdcr (uic0cr, 0x00000009);	/* SMI & UIC1 crit are critical */
-	mtdcr (uic0pr, 0xfffffe13);	/* per ref-board manual */
-	mtdcr (uic0tr, 0x01c00008);	/* per ref-board manual */
-	mtdcr (uic0vr, 0x00000001);	/* int31 highest, base=0x000 */
-	mtdcr (uic0sr, 0xffffffff);	/* clear all */
-
+	/*
+	 * Because of the interrupt handling rework to handle 440GX interrupts
+	 * with the common code, we needed to change names of the UIC registers.
+	 * Here the new relationship:
+	 *
+	 * U-Boot name	440GX name
+	 * -----------------------
+	 * UIC0		UICB0
+	 * UIC1		UIC0
+	 * UIC2		UIC1
+	 * UIC3		UIC2
+	 */
 	mtdcr (uic1sr, 0xffffffff);	/* clear all */
 	mtdcr (uic1er, 0x00000000);	/* disable all */
-	mtdcr (uic1cr, 0x00000000);	/* all non-critical */
-	mtdcr (uic1pr, 0xffffe0ff);	/* per ref-board manual */
-	mtdcr (uic1tr, 0x00ffc000);	/* per ref-board manual */
+	mtdcr (uic1cr, 0x00000009);	/* SMI & UIC1 crit are critical */
+	mtdcr (uic1pr, 0xfffffe13);	/* per ref-board manual */
+	mtdcr (uic1tr, 0x01c00008);	/* per ref-board manual */
 	mtdcr (uic1vr, 0x00000001);	/* int31 highest, base=0x000 */
 	mtdcr (uic1sr, 0xffffffff);	/* clear all */
 
 	mtdcr (uic2sr, 0xffffffff);	/* clear all */
 	mtdcr (uic2er, 0x00000000);	/* disable all */
 	mtdcr (uic2cr, 0x00000000);	/* all non-critical */
-	mtdcr (uic2pr, 0xffffffff);	/* per ref-board manual */
-	mtdcr (uic2tr, 0x00ff8c0f);	/* per ref-board manual */
+	mtdcr (uic2pr, 0xffffe0ff);	/* per ref-board manual */
+	mtdcr (uic2tr, 0x00ffc000);	/* per ref-board manual */
 	mtdcr (uic2vr, 0x00000001);	/* int31 highest, base=0x000 */
 	mtdcr (uic2sr, 0xffffffff);	/* clear all */
 
-	mtdcr (uicb0sr, 0xfc000000); /* clear all */
-	mtdcr (uicb0er, 0x00000000); /* disable all */
-	mtdcr (uicb0cr, 0x00000000); /* all non-critical */
-	mtdcr (uicb0pr, 0xfc000000); /* */
-	mtdcr (uicb0tr, 0x00000000); /* */
-	mtdcr (uicb0vr, 0x00000001); /* */
+	mtdcr (uic3sr, 0xffffffff);	/* clear all */
+	mtdcr (uic3er, 0x00000000);	/* disable all */
+	mtdcr (uic3cr, 0x00000000);	/* all non-critical */
+	mtdcr (uic3pr, 0xffffffff);	/* per ref-board manual */
+	mtdcr (uic3tr, 0x00ff8c0f);	/* per ref-board manual */
+	mtdcr (uic3vr, 0x00000001);	/* int31 highest, base=0x000 */
+	mtdcr (uic3sr, 0xffffffff);	/* clear all */
+
+	mtdcr (uic0sr, 0xfc000000); /* clear all */
+	mtdcr (uic0er, 0x00000000); /* disable all */
+	mtdcr (uic0cr, 0x00000000); /* all non-critical */
+	mtdcr (uic0pr, 0xfc000000); /* */
+	mtdcr (uic0tr, 0x00000000); /* */
+	mtdcr (uic0vr, 0x00000001); /* */
 	mfsdr (sdr_mfr, mfr);
 	mfr &= ~SDR0_MFR_ECS_MASK;
 /*	mtsdr(sdr_mfr, mfr); */