powerpc: use 'video-mode' environment variable to configure DIU

Use the 'video-mode' environment variable (for Freescale chips that have a
DIU display controller) to designate the full video configuration.  Previously,
the DIU driver used the 'monitor' variable, and it was used only to determine
the output video port.

The old definition of the "monitor" environment variable only determines
which video port to use for output.  This variable was set to a number (0,
1, or sometimes 2) to specify a DVI, LVDS, or Dual-LVDS port.  The
resolution was hard-coded into board-specific code.  The Linux command-line
arguments needed to be hard-coded to the proper video definition string.

Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
diff --git a/board/freescale/p1022ds/diu.c b/board/freescale/p1022ds/diu.c
index b37e0e2..7d1f6aa 100644
--- a/board/freescale/p1022ds/diu.c
+++ b/board/freescale/p1022ds/diu.c
@@ -12,6 +12,7 @@
 
 #include <common.h>
 #include <command.h>
+#include <linux/ctype.h>
 #include <asm/io.h>
 #include <stdio_dev.h>
 #include <video_fb.h>
@@ -81,10 +82,10 @@
 	out_be32(&gur->clkdvdr, temp | 0x80000000 | ((pixval & 0x1F) << 16));
 }
 
-int platform_diu_init(unsigned int *xres, unsigned int *yres)
+int platform_diu_init(unsigned int xres, unsigned int yres, const char *port)
 {
 	ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
-	char *monitor_port;
+	const char *name;
 	u32 pixel_format;
 	u8 temp;
 
@@ -100,21 +101,23 @@
 
 	temp = in_8(&pixis->brdcfg1);
 
-	monitor_port = getenv("monitor");
-	if (!strncmp(monitor_port, "1", 1)) { /* 1 - Single link LVDS */
-		*xres = 1024;
-		*yres = 768;
-		/* Enable the DFP port, disable the DVI and the backlight */
-		temp &= ~(PX_BRDCFG1_DVIEN | PX_BRDCFG1_BACKLIGHT);
-		temp |= PX_BRDCFG1_DFPEN;
+	if (strncmp(port, "lvds", 4) == 0) {
+		/* Single link LVDS */
+		temp &= ~PX_BRDCFG1_DVIEN;
+		/*
+		 * LVDS also needs backlight enabled, otherwise the display
+		 * will be blank.
+		 */
+		temp |= (PX_BRDCFG1_DFPEN | PX_BRDCFG1_BACKLIGHT);
+		name = "Single-Link LVDS";
 	} else {	/* DVI */
-		*xres = 1280;
-		*yres = 1024;
 		/* Enable the DVI port, disable the DFP and the backlight */
 		temp &= ~(PX_BRDCFG1_DFPEN | PX_BRDCFG1_BACKLIGHT);
 		temp |= PX_BRDCFG1_DVIEN;
+		name = "DVI";
 	}
 
+	printf("DIU:   Switching to %s monitor @ %ux%u\n", name, xres, yres);
 	out_8(&pixis->brdcfg1, temp);
 
 	/*
@@ -136,7 +139,7 @@
 	clrsetbits_be32(&gur->pmuxcr, PMUXCR_ELBCDIU_MASK, PMUXCR_ELBCDIU_DIU);
 	pmuxcr = in_be32(&gur->pmuxcr);
 
-	return fsl_diu_init(*xres, pixel_format, 0);
+	return fsl_diu_init(xres, pixel_format, 0);
 }
 
 /*