drm/mgag200: Move mode-setting code into separate helper function

The mode-setting code is now located in mgag200_set_mode_regs(), sans
a few flags that will be moved in a later patch for clarity.

v2:
	* replace uint8_t with u8
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: John Donnelly <John.p.donnelly@oracle.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Emil Velikov <emil.velikov@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515083233.32036-5-tzimmermann@suse.de

drivers/gpu/drm/mgag200/mgag200_mode.c

@@ -911,6 +911,79 @@ static int mga_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
 	return mga_crtc_do_set_base(mdev, fb, old_fb);
 }
 
+static void mgag200_set_mode_regs(struct mga_device *mdev,
+				  const struct drm_display_mode *mode)
+{
+	unsigned int hdisplay, hsyncstart, hsyncend, htotal;
+	unsigned int vdisplay, vsyncstart, vsyncend, vtotal;
+	u8 misc = 0;
+	u8 crtcext1, crtcext2, crtcext5;
+
+	hdisplay = mode->hdisplay / 8 - 1;
+	hsyncstart = mode->hsync_start / 8 - 1;
+	hsyncend = mode->hsync_end / 8 - 1;
+	htotal = mode->htotal / 8 - 1;
+
+	/* Work around hardware quirk */
+	if ((htotal & 0x07) == 0x06 || (htotal & 0x07) == 0x04)
+		htotal++;
+
+	vdisplay = mode->vdisplay - 1;
+	vsyncstart = mode->vsync_start - 1;
+	vsyncend = mode->vsync_end - 1;
+	vtotal = mode->vtotal - 2;
+
+	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+		misc |= 0x40;
+	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+		misc |= 0x80;
+
+	crtcext1 = (((htotal - 4) & 0x100) >> 8) |
+		   ((hdisplay & 0x100) >> 7) |
+		   ((hsyncstart & 0x100) >> 6) |
+		    (htotal & 0x40);
+	if (mdev->type == G200_WB || mdev->type == G200_EW3)
+		crtcext1 |= BIT(7) | /* vrsten */
+			    BIT(3); /* hrsten */
+
+	crtcext2 = ((vtotal & 0xc00) >> 10) |
+		   ((vdisplay & 0x400) >> 8) |
+		   ((vdisplay & 0xc00) >> 7) |
+		   ((vsyncstart & 0xc00) >> 5) |
+		   ((vdisplay & 0x400) >> 3);
+	crtcext5 = 0x00;
+
+	WREG_CRT(0, htotal - 4);
+	WREG_CRT(1, hdisplay);
+	WREG_CRT(2, hdisplay);
+	WREG_CRT(3, (htotal & 0x1F) | 0x80);
+	WREG_CRT(4, hsyncstart);
+	WREG_CRT(5, ((htotal & 0x20) << 2) | (hsyncend & 0x1F));
+	WREG_CRT(6, vtotal & 0xFF);
+	WREG_CRT(7, ((vtotal & 0x100) >> 8) |
+		 ((vdisplay & 0x100) >> 7) |
+		 ((vsyncstart & 0x100) >> 6) |
+		 ((vdisplay & 0x100) >> 5) |
+		 ((vdisplay & 0x100) >> 4) | /* linecomp */
+		 ((vtotal & 0x200) >> 4) |
+		 ((vdisplay & 0x200) >> 3) |
+		 ((vsyncstart & 0x200) >> 2));
+	WREG_CRT(9, ((vdisplay & 0x200) >> 4) |
+		 ((vdisplay & 0x200) >> 3));
+	WREG_CRT(16, vsyncstart & 0xFF);
+	WREG_CRT(17, (vsyncend & 0x0F) | 0x20);
+	WREG_CRT(18, vdisplay & 0xFF);
+	WREG_CRT(20, 0);
+	WREG_CRT(21, vdisplay & 0xFF);
+	WREG_CRT(22, (vtotal + 1) & 0xFF);
+	WREG_CRT(23, 0xc3);
+	WREG_CRT(24, vdisplay & 0xFF);
+
+	WREG_ECRT(0x01, crtcext1);
+	WREG_ECRT(0x02, crtcext2);
+	WREG_ECRT(0x05, crtcext5);
+}
+
 static int mga_crtc_mode_set(struct drm_crtc *crtc,
 				struct drm_display_mode *mode,
 				struct drm_display_mode *adjusted_mode,
@@ -919,8 +992,6 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 	struct drm_device *dev = crtc->dev;
 	struct mga_device *mdev = to_mga_device(dev);
 	const struct drm_framebuffer *fb = crtc->primary->fb;
-	int hdisplay, hsyncstart, hsyncend, htotal;
-	int vdisplay, vsyncstart, vsyncend, vtotal;
 	int pitch;
 	int option = 0, option2 = 0;
 	int i;
@@ -999,12 +1070,6 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 		break;
 	}
 
-	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
-		misc |= 0x40;
-	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
-		misc |= 0x80;
-
-
 	for (i = 0; i < sizeof(dacvalue); i++) {
 		if ((i <= 0x17) ||
 		    (i == 0x1b) ||
@@ -1044,20 +1109,6 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 	else
 		pitch = pitch >> (4 - bppshift);
 
-	hdisplay = mode->hdisplay / 8 - 1;
-	hsyncstart = mode->hsync_start / 8 - 1;
-	hsyncend = mode->hsync_end / 8 - 1;
-	htotal = mode->htotal / 8 - 1;
-
-	/* Work around hardware quirk */
-	if ((htotal & 0x07) == 0x06 || (htotal & 0x07) == 0x04)
-		htotal++;
-
-	vdisplay = mode->vdisplay - 1;
-	vsyncstart = mode->vsync_start - 1;
-	vsyncend = mode->vsync_end - 1;
-	vtotal = mode->vtotal - 2;
-
 	WREG_GFX(0, 0);
 	WREG_GFX(1, 0);
 	WREG_GFX(2, 0);
@@ -1068,61 +1119,26 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 	WREG_GFX(7, 0xf);
 	WREG_GFX(8, 0xf);
 
-	WREG_CRT(0, htotal - 4);
-	WREG_CRT(1, hdisplay);
-	WREG_CRT(2, hdisplay);
-	WREG_CRT(3, (htotal & 0x1F) | 0x80);
-	WREG_CRT(4, hsyncstart);
-	WREG_CRT(5, ((htotal & 0x20) << 2) | (hsyncend & 0x1F));
-	WREG_CRT(6, vtotal & 0xFF);
-	WREG_CRT(7, ((vtotal & 0x100) >> 8) |
-		 ((vdisplay & 0x100) >> 7) |
-		 ((vsyncstart & 0x100) >> 6) |
-		 ((vdisplay & 0x100) >> 5) |
-		 ((vdisplay & 0x100) >> 4) | /* linecomp */
-		 ((vtotal & 0x200) >> 4)|
-		 ((vdisplay & 0x200) >> 3) |
-		 ((vsyncstart & 0x200) >> 2));
-	WREG_CRT(9, ((vdisplay & 0x200) >> 4) |
-		 ((vdisplay & 0x200) >> 3));
 	WREG_CRT(10, 0);
 	WREG_CRT(11, 0);
 	WREG_CRT(12, 0);
 	WREG_CRT(13, 0);
 	WREG_CRT(14, 0);
 	WREG_CRT(15, 0);
-	WREG_CRT(16, vsyncstart & 0xFF);
-	WREG_CRT(17, (vsyncend & 0x0F) | 0x20);
-	WREG_CRT(18, vdisplay & 0xFF);
 	WREG_CRT(19, pitch & 0xFF);
-	WREG_CRT(20, 0);
-	WREG_CRT(21, vdisplay & 0xFF);
-	WREG_CRT(22, (vtotal + 1) & 0xFF);
-	WREG_CRT(23, 0xc3);
-	WREG_CRT(24, vdisplay & 0xFF);
+
+	mgag200_set_mode_regs(mdev, mode);
 
 	ext_vga[0] = 0;
-	ext_vga[5] = 0;
 
 	/* TODO interlace */
 
 	ext_vga[0] |= (pitch & 0x300) >> 4;
-	ext_vga[1] = (((htotal - 4) & 0x100) >> 8) |
-		((hdisplay & 0x100) >> 7) |
-		((hsyncstart & 0x100) >> 6) |
-		(htotal & 0x40);
-	ext_vga[2] = ((vtotal & 0xc00) >> 10) |
-		((vdisplay & 0x400) >> 8) |
-		((vdisplay & 0xc00) >> 7) |
-		((vsyncstart & 0xc00) >> 5) |
-		((vdisplay & 0x400) >> 3);
 	if (fb->format->cpp[0] * 8 == 24)
 		ext_vga[3] = (((1 << bppshift) * 3) - 1) | 0x80;
 	else
 		ext_vga[3] = ((1 << bppshift) - 1) | 0x80;
 	ext_vga[4] = 0;
-	if (mdev->type == G200_WB || mdev->type == G200_EW3)
-		ext_vga[1] |= 0x88;
 
 	/* Set pixel clocks */
 	misc = 0x2d;
@@ -1130,9 +1146,9 @@ static int mga_crtc_mode_set(struct drm_crtc *crtc,
 
 	mga_crtc_set_plls(mdev, mode->clock);
 
-	for (i = 0; i < 6; i++) {
-		WREG_ECRT(i, ext_vga[i]);
-	}
+	WREG_ECRT(0, ext_vga[0]);
+	WREG_ECRT(3, ext_vga[3]);
+	WREG_ECRT(4, ext_vga[4]);
 
 	if (mdev->type == G200_ER)
 		WREG_ECRT(0x24, 0x5);