cirrusfb: use 24bpp instead of 32bpp

The 32bpp is supported only on the latest Cirrus Logic chips.  Use the
24bpp which is supported at least since Alpine chips (GD543x).

Change 32bpp mode setting to 24bpp mode.  Change acceleration as well.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/cirrusfb.c

@@ -95,10 +95,10 @@
 /* board types */
 enum cirrus_board {
 	BT_NONE = 0,
-	BT_SD64,
-	BT_PICCOLO,
-	BT_PICASSO,
-	BT_SPECTRUM,
+	BT_SD64,	/* GD5434 */
+	BT_PICCOLO,	/* GD5426 */
+	BT_PICASSO,	/* GD5426 or GD5428 */
+	BT_SPECTRUM,	/* GD5426 or GD5428 */
 	BT_PICASSO4,	/* GD5446 */
 	BT_ALPINE,	/* GD543x/4x */
 	BT_GD5480,
@@ -488,7 +488,7 @@ static int cirrusfb_check_pixclock(const struct fb_var_screeninfo *var,
 	 * the VCLK is double the pixel clock. */
 	switch (var->bits_per_pixel) {
 	case 16:
-	case 32:
+	case 24:
 		if (var->xres <= 800)
 			/* Xbh has this type of clock for 32-bit */
 			freq /= 2;
@@ -535,11 +535,11 @@ static int cirrusfb_check_var(struct fb_var_screeninfo *var,
 		var->blue.length = 5;
 		break;
 
-	case 32:
+	case 24:
 		if (isPReP) {
-			var->red.offset = 8;
-			var->green.offset = 16;
-			var->blue.offset = 24;
+			var->red.offset = 0;
+			var->green.offset = 8;
+			var->blue.offset = 16;
 		} else {
 			var->red.offset = 16;
 			var->green.offset = 8;
@@ -670,7 +670,7 @@ static int cirrusfb_set_par_foo(struct fb_info *info)
 		break;
 
 	case 16:
-	case 32:
+	case 24:
 		info->fix.line_length = var->xres_virtual *
 					var->bits_per_pixel >> 3;
 		info->fix.visual = FB_VISUAL_TRUECOLOR;
@@ -813,6 +813,9 @@ static int cirrusfb_set_par_foo(struct fb_info *info)
 	vga_wcrt(regbase, CL_CRT1A, tmp);
 
 	freq = PICOS2KHZ(var->pixclock);
+	if (cinfo->btype == BT_ALPINE && var->bits_per_pixel == 24)
+		freq *= 3;
+
 	bestclock(freq, &nom, &den, &div);
 
 	dev_dbg(info->device, "VCLK freq: %ld kHz  nom: %d  den: %d  div: %d\n",
@@ -1140,16 +1143,16 @@ static int cirrusfb_set_par_foo(struct fb_info *info)
 
 	/******************************************************
 	 *
-	 * 32 bpp
+	 * 24 bpp
 	 *
 	 */
 
-	else if (var->bits_per_pixel == 32) {
-		dev_dbg(info->device, "preparing for 32 bit deep display\n");
+	else if (var->bits_per_pixel == 24) {
+		dev_dbg(info->device, "preparing for 24 bit deep display\n");
 		switch (cinfo->btype) {
 		case BT_SD64:
 			/* Extended Sequencer Mode: 256c col. mode */
-			vga_wseq(regbase, CL_SEQR7, 0xf9);
+			vga_wseq(regbase, CL_SEQR7, 0xf5);
 			/* MCLK select */
 			vga_wseq(regbase, CL_SEQR1F, 0x1e);
 			break;
@@ -1173,11 +1176,11 @@ static int cirrusfb_set_par_foo(struct fb_info *info)
 
 		case BT_PICASSO4:
 		case BT_ALPINE:
-			vga_wseq(regbase, CL_SEQR7, 0xa9);
+			vga_wseq(regbase, CL_SEQR7, 0xa5);
 			break;
 
 		case BT_GD5480:
-			vga_wseq(regbase, CL_SEQR7, 0x19);
+			vga_wseq(regbase, CL_SEQR7, 0x15);
 			/* We already set SRF and SR1F */
 			break;
 
@@ -1185,8 +1188,8 @@ static int cirrusfb_set_par_foo(struct fb_info *info)
 		case BT_LAGUNAB:
 			vga_wseq(regbase, CL_SEQR7,
 				vga_rseq(regbase, CL_SEQR7) & ~0x01);
-			control |= 0x6000;
-			format |= 0x3400;
+			control |= 0x4000;
+			format |= 0x2400;
 			threshold |= 0x20;
 			break;
 
@@ -1385,9 +1388,6 @@ static int cirrusfb_pan_display(struct fb_var_screeninfo *var,
 	if (info->var.bits_per_pixel == 1)
 		vga_wattr(cinfo->regbase, CL_AR33, xpix);
 
-	if (!is_laguna(cinfo))
-		cirrusfb_WaitBLT(cinfo->regbase);
-
 	return 0;
 }
 
@@ -1492,22 +1492,18 @@ static void init_vgachip(struct fb_info *info)
 		/* disable flickerfixer */
 		vga_wcrt(cinfo->regbase, CL_CRT51, 0x00);
 		mdelay(100);
-		/* from Klaus' NetBSD driver: */
-		vga_wgfx(cinfo->regbase, CL_GR2F, 0x00);
-		/* put blitter into 542x compat */
-		vga_wgfx(cinfo->regbase, CL_GR33, 0x00);
 		/* mode */
 		vga_wgfx(cinfo->regbase, CL_GR31, 0x00);
-		break;
-
-	case BT_GD5480:
+	case BT_GD5480:  /* fall through */
 		/* from Klaus' NetBSD driver: */
 		vga_wgfx(cinfo->regbase, CL_GR2F, 0x00);
+	case BT_ALPINE:  /* fall through */
+		/* put blitter into 542x compat */
+		vga_wgfx(cinfo->regbase, CL_GR33, 0x00);
 		break;
 
 	case BT_LAGUNA:
 	case BT_LAGUNAB:
-	case BT_ALPINE:
 		/* Nothing to do to reset the board. */
 		break;
 
@@ -1831,10 +1827,13 @@ static void cirrusfb_imageblit(struct fb_info *info,
 			       const struct fb_image *image)
 {
 	struct cirrusfb_info *cinfo = info->par;
+	unsigned char op = (info->var.bits_per_pixel == 24) ? 0xc : 0x4;
 
 	if (info->state != FBINFO_STATE_RUNNING)
 		return;
-	if (info->flags & FBINFO_HWACCEL_DISABLED)
+	/* Alpine acceleration does not work at 24bpp ?!? */
+	if (info->flags & FBINFO_HWACCEL_DISABLED || image->depth != 1 ||
+	    (cinfo->btype == BT_ALPINE && op == 0xc))
 		cfb_imageblit(info, image);
 	else {
 		unsigned size = ((image->width + 7) >> 3) * image->height;
@@ -1848,15 +1847,22 @@ static void cirrusfb_imageblit(struct fb_info *info,
 			fg = ((u32 *)(info->pseudo_palette))[image->fg_color];
 			bg = ((u32 *)(info->pseudo_palette))[image->bg_color];
 		}
-		cirrusfb_WaitBLT(cinfo->regbase);
-		/* byte rounded scanlines */
-		vga_wgfx(cinfo->regbase, CL_GR33, 0x00);
+		if (info->var.bits_per_pixel == 24) {
+			/* clear background first */
+			cirrusfb_RectFill(cinfo->regbase,
+					  info->var.bits_per_pixel,
+					  (image->dx * m) / 8, image->dy,
+					  (image->width * m) / 8,
+					  image->height,
+					  bg, bg,
+					  info->fix.line_length, 0x40);
+		}
 		cirrusfb_RectFill(cinfo->regbase,
 				  info->var.bits_per_pixel,
 				  (image->dx * m) / 8, image->dy,
 				  (image->width * m) / 8, image->height,
 				  fg, bg,
-				  info->fix.line_length, 0x04);
+				  info->fix.line_length, op);
 		memcpy(info->screen_base, image->data, size);
 	}
 }
@@ -2743,9 +2749,12 @@ static void cirrusfb_RectFill(u8 __iomem *regbase, int bits_per_pixel,
 		vga_wgfx(regbase, CL_GR11, fg_color >> 8);
 		op = 0x90;
 	}
-	if (bits_per_pixel == 32) {
+	if (bits_per_pixel >= 24) {
 		vga_wgfx(regbase, CL_GR12, bg_color >> 16);
 		vga_wgfx(regbase, CL_GR13, fg_color >> 16);
+		op = 0xa0;
+	}
+	if (bits_per_pixel == 32) {
 		vga_wgfx(regbase, CL_GR14, bg_color >> 24);
 		vga_wgfx(regbase, CL_GR15, fg_color >> 24);
 		op = 0xb0;