Blackfin: bf533-stamp: rewrite resource swap logic

The old swap function tended to clobber unrelated pins and screw up masks.
Rewrite the thing from scratch so it only uses the resources it needs.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

board/bf533-stamp/bf533-stamp.c

@@ -54,29 +54,23 @@ phys_size_t initdram(int board_type)
 	return gd->bd->bi_memsize;
 }
 
+/* PF0 and PF1 are used to switch between the ethernet and flash:
+ *         PF0  PF1
+ *  flash:  0    0
+ *  ether:  1    0
+ */
 void swap_to(int device_id)
 {
-
-	if (device_id == ETHERNET) {
-		*pFIO_DIR = PF0;
-		SSYNC();
-		*pFIO_FLAG_S = PF0;
-		SSYNC();
-	} else if (device_id == FLASH) {
-		*pFIO_DIR = (PF4 | PF3 | PF2 | PF1 | PF0);
-		*pFIO_FLAG_S = (PF4 | PF3 | PF2);
-		*pFIO_MASKA_D = (PF8 | PF6 | PF5);
-		*pFIO_MASKB_D = (PF7);
-		*pFIO_POLAR = (PF8 | PF6 | PF5);
-		*pFIO_EDGE = (PF8 | PF7 | PF6 | PF5);
-		*pFIO_INEN = (PF8 | PF7 | PF6 | PF5);
-		*pFIO_FLAG_D = (PF4 | PF3 | PF2);
-		SSYNC();
-	} else {
-		printf("Unknown bank to switch\n");
-	}
-
-	return;
+	bfin_write_FIO_DIR(bfin_read_FIO_DIR() | PF1 | PF0);
+	SSYNC();
+	bfin_write_FIO_FLAG_C(PF1);
+	if (device_id == ETHERNET)
+		bfin_write_FIO_FLAG_S(PF0);
+	else if (device_id == FLASH)
+		bfin_write_FIO_FLAG_C(PF0);
+	else
+		printf("Unknown device to switch\n");
+	SSYNC();
 }
 
 #if defined(CONFIG_MISC_INIT_R)
@@ -104,9 +98,6 @@ int misc_init_r(void)
 	if (cf_stat) {
 		printf("Booting from COMPACT flash\n");
 
-		/* Set cycle time for CF */
-		*(volatile unsigned long *)ambctl1 = CF_AMBCTL1VAL;
-
 		for (i = 0; i < 0x1000; i++)
 			asm("nop;");
 		for (i = 0; i < 0x1000; i++)