diff --git a/drivers/gpu/drm/via/via_crtc.c b/drivers/gpu/drm/via/via_crtc.c
new file mode 100644
index 000000000000..afd42bd99f25
--- /dev/null
+++ b/drivers/gpu/drm/via/via_crtc.c
@@ -0,0 +1,2324 @@
+/*
+ * Copyright © 2019-2020 Kevin Brace.
+ * Copyright 2012 James Simmons. All Rights Reserved.
+ * Copyright 1998-2009 VIA Technologies, Inc. All Rights Reserved.
+ * Copyright 2001-2009 S3 Graphics, Inc. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sub license,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHOR(S) OR COPYRIGHT HOLDER(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Author(s):
+ * Kevin Brace <kevinbrace@bracecomputerlab.com>
+ * James Simmons <jsimmons@infradead.org>
+ */
+
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_atomic_state_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_mode.h>
+#include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_plane.h>
+#include <drm/drm_plane_helper.h>
+
+#include <drm/ttm/ttm_bo_api.h>
+
+#include "via_drv.h"
+#include "via_disp_reg.h"
+
+
+static struct vga_regset vpit_table[] = {
+	{VGA_SEQ_I, 0x01, 0xFF, 0x01 },
+	{VGA_SEQ_I, 0x02, 0xFF, 0x0F },
+	{VGA_SEQ_I, 0x03, 0xFF, 0x00 },
+	{VGA_SEQ_I, 0x04, 0xFF, 0x0E },
+	{VGA_GFX_I, 0x00, 0xFF, 0x00 },
+	{VGA_GFX_I, 0x01, 0xFF, 0x00 },
+	{VGA_GFX_I, 0x02, 0xFF, 0x00 },
+	{VGA_GFX_I, 0x03, 0xFF, 0x00 },
+	{VGA_GFX_I, 0x04, 0xFF, 0x00 },
+	{VGA_GFX_I, 0x05, 0xFF, 0x00 },
+	{VGA_GFX_I, 0x06, 0xFF, 0x05 },
+	{VGA_GFX_I, 0x07, 0xFF, 0x0F },
+	{VGA_GFX_I, 0x08, 0xFF, 0xFF }
+};
+
+static void via_iga_common_init(void __iomem *regs)
+{
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	/* Be careful with 3C5.15[5] - Wrap Around Disable.
+	 * It must be set to 1 for proper operation. */
+	/* 3C5.15[5]   - Wrap Around Disable
+	 *               0: Disable (For Mode 0-13)
+	 *               1: Enable
+	 * 3C5.15[1]   - Extended Display Mode Enable
+	 *               0: Disable
+	 *               1: Enable */
+	svga_wseq_mask(regs, 0x15, BIT(5) | BIT(1), BIT(5) | BIT(1));
+
+	/*
+	 * Disable simultaneous display.
+	 * Turning this on causes IGA1 to have a display issue.
+	 */
+	/*
+	 * 3X5.6B[3]   - Simultaneous Display Enable
+	 *               0: Disable
+	 *               1: Enable
+	 */
+	svga_wcrt_mask(regs, 0x6B, 0x00, BIT(3));
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static void via_iga1_set_color_depth(struct via_drm_priv *dev_priv,
+					u8 depth)
+{
+	u8 value;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	value = 0x00;
+
+	/* Set the color depth for IGA1. */
+	switch (depth) {
+	case 8:
+		break;
+	case 16:
+		/* Bit 4 is for 555 (15-bit) / 565 (16-bit) color selection. */
+		value |= BIT(4) | BIT(2);
+		break;
+	case 24:
+		value |= BIT(3) | BIT(2);
+		break;
+	default:
+		break;
+	}
+
+	if ((depth == 8) || (depth == 16) || (depth == 24)) {
+		/* 3C5.15[4]   - Hi Color Mode Select
+		 *               0: 555
+		 *               1: 565
+		 * 3C5.15[3:2] - Display Color Depth Select
+		 *               00: 8bpp
+		 *               01: 16bpp
+		 *               10: 30bpp
+		 *               11: 32bpp */
+		svga_wseq_mask(VGABASE, 0x15, value,
+				BIT(4) | BIT(3) | BIT(2));
+		DRM_INFO("IGA1 Color Depth: %d bit\n", depth);
+	} else {
+		DRM_ERROR("Unsupported IGA1 Color Depth: %d bit\n",
+				depth);
+	}
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static void via_iga2_set_color_depth(struct via_drm_priv *dev_priv,
+					u8 depth)
+{
+	u8 value;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	value = 0x00;
+
+	/* Set the color depth for IGA2. */
+	switch (depth) {
+	case 8:
+		break;
+	case 16:
+		value = BIT(6);
+		break;
+	case 24:
+		value = BIT(7) | BIT(6);
+		break;
+	default:
+		break;
+	}
+
+	if ((depth == 8) || (depth == 16) || (depth == 24)) {
+		/* 3X5.67[7:6] - Display Color Depth Select
+		 *               00: 8bpp
+		 *               01: 16bpp
+		 *               10: 30bpp
+		 *               11: 32bpp */
+		svga_wcrt_mask(VGABASE, 0x67, value, 0xC0);
+		DRM_INFO("IGA2 Color Depth: %d bit\n", depth);
+	} else {
+		DRM_ERROR("Unsupported IGA2 Color Depth: %d bit\n",
+				depth);
+	}
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static int via_gamma_set(struct drm_crtc *crtc,
+				u16 *r, u16 *g, u16 *b,
+				uint32_t size,
+				struct drm_modeset_acquire_ctx *ctx)
+{
+	struct drm_device *dev = crtc->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	struct via_crtc *iga = container_of(crtc,
+						struct via_crtc, base);
+	int end = (size > 256) ? 256 : size, i;
+	u8 val = 0;
+	int ret = 0;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if ((!crtc->enabled) || (!crtc->primary->fb)) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	if (!iga->index) {
+		/*
+		 * Access IGA1's pallette LUT.
+		 */
+		svga_wseq_mask(VGABASE, 0x1A, 0x00, BIT(0));
+
+		/*
+		 * Is it an 8-bit color mode?
+		 */
+		if (crtc->primary->fb->format->cpp[0] == 1) {
+			/* Change to Primary Display's LUT */
+			val = vga_rseq(VGABASE, 0x1B);
+			vga_wseq(VGABASE, 0x1B, val);
+			val = vga_rcrt(VGABASE, 0x67);
+			vga_wcrt(VGABASE, 0x67, val);
+
+			/* Fill in IGA1's LUT */
+			for (i = 0; i < end; i++) {
+				/* Bit mask of palette */
+				vga_w(VGABASE, VGA_PEL_MSK, 0xFF);
+				vga_w(VGABASE, VGA_PEL_IW, i);
+				vga_w(VGABASE, VGA_PEL_D, r[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, g[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, b[i] >> 8);
+			}
+			/* enable LUT */
+			svga_wseq_mask(VGABASE, 0x1B, 0x00, BIT(0));
+			/*
+			 * Disable gamma in case it was enabled
+			 * previously
+			 */
+			svga_wcrt_mask(VGABASE, 0x33, 0x00, BIT(7));
+		} else {
+			/* Enable Gamma */
+			svga_wcrt_mask(VGABASE, 0x33, BIT(7), BIT(7));
+
+			/* Fill in IGA1's gamma */
+			for (i = 0; i < end; i++) {
+				/* bit mask of palette */
+				vga_w(VGABASE, VGA_PEL_MSK, 0xFF);
+				vga_w(VGABASE, VGA_PEL_IW, i);
+				vga_w(VGABASE, VGA_PEL_D, r[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, g[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, b[i] >> 8);
+			}
+		}
+	} else {
+		/*
+		 * Access IGA2's pallette LUT.
+		 */
+		svga_wseq_mask(VGABASE, 0x1A, BIT(0), BIT(0));
+
+		/*
+		 * Is it an 8-bit color mode?
+		 */
+		if (crtc->primary->fb->format->cpp[0] == 1) {
+			/* Enable Secondary Display Engine */
+			svga_wseq_mask(VGABASE, 0x1B, BIT(7), BIT(7));
+			/* Second Display Color Depth, 8bpp */
+			svga_wcrt_mask(VGABASE, 0x67, 0x3F, 0x3F);
+
+			/*
+			 * Enable second display channel just in case.
+			 */
+			if (!(vga_rcrt(VGABASE, 0x6A) & BIT(7)))
+				svga_wcrt_mask(VGABASE, 0x6A,
+						BIT(7), BIT(7));
+
+			/* Fill in IGA2's LUT */
+			for (i = 0; i < end; i++) {
+				/* Bit mask of palette */
+				vga_w(VGABASE, VGA_PEL_MSK, 0xFF);
+				vga_w(VGABASE, VGA_PEL_IW, i);
+				vga_w(VGABASE, VGA_PEL_D, r[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, g[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, b[i] >> 8);
+			}
+			/*
+			 * Disable gamma in case it was enabled
+			 * previously
+			 */
+			svga_wcrt_mask(VGABASE, 0x6A, 0x00, BIT(1));
+		} else {
+			u8 reg_bits = BIT(1);
+
+			/* Bit 1 enables gamma */
+			svga_wcrt_mask(VGABASE, 0x6A, BIT(1), BIT(1));
+
+			/* Old platforms LUT are 6 bits in size.
+			 * Newer it is 8 bits. */
+			switch (pdev->device) {
+			case PCI_DEVICE_ID_VIA_CLE266:
+			case PCI_DEVICE_ID_VIA_KM400:
+			case PCI_DEVICE_ID_VIA_K8M800:
+			case PCI_DEVICE_ID_VIA_PM800:
+				break;
+
+			default:
+				reg_bits |= BIT(5);
+				break;
+			}
+			svga_wcrt_mask(VGABASE, 0x6A, reg_bits,
+					reg_bits);
+
+			/*
+			 * Before we fill the second LUT, we have to
+			 * enable second display channel. If it's
+			 * enabled before, we don't need to do that,
+			 * or else the secondary display will be dark
+			 * for about 1 sec and then be turned on
+			 * again.
+			 */
+			if (!(vga_rcrt(VGABASE, 0x6A) & BIT(7)))
+				svga_wcrt_mask(VGABASE, 0x6A,
+						BIT(7), BIT(7));
+
+			/* Fill in IGA2's gamma */
+			for (i = 0; i < end; i++) {
+				/* bit mask of palette */
+				vga_w(VGABASE, VGA_PEL_MSK, 0xFF);
+				vga_w(VGABASE, VGA_PEL_IW, i);
+				vga_w(VGABASE, VGA_PEL_D, r[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, g[i] >> 8);
+				vga_w(VGABASE, VGA_PEL_D, b[i] >> 8);
+			}
+		}
+	}
+
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return ret;
+}
+
+static void via_crtc_destroy(struct drm_crtc *crtc)
+{
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+
+	drm_crtc_cleanup(&iga->base);
+	kfree(iga);
+}
+
+static const struct drm_crtc_funcs via_drm_crtc_funcs = {
+	.reset = drm_atomic_helper_crtc_reset,
+	.gamma_set = via_gamma_set,
+	.set_config = drm_atomic_helper_set_config,
+	.destroy = via_crtc_destroy,
+	.page_flip = drm_atomic_helper_page_flip,
+	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+};
+
+static void via_load_vpit_regs(struct via_drm_priv *dev_priv)
+{
+	u8 ar[] = {0x00, 0x01, 0x02, 0x03,
+			0x04, 0x05, 0x06, 0x07,
+			0x08, 0x09, 0x0A, 0x0B,
+			0x0C, 0x0D, 0x0E, 0x0F,
+			0x01, 0x00, 0x0F, 0x00};
+	struct vga_registers vpit_regs;
+	unsigned int i = 0;
+	u8 reg_value = 0;
+
+	/* Enable changing the palette registers */
+	reg_value = vga_r(VGABASE, VGA_IS1_RC);
+	vga_w(VGABASE, VGA_ATT_W, 0x00);
+
+	/* Write Misc register */
+	vga_w(VGABASE, VGA_MIS_W, 0xCF);
+
+	/* Fill VPIT registers */
+	vpit_regs.count = ARRAY_SIZE(vpit_table);
+	vpit_regs.regs = vpit_table;
+	load_register_tables(VGABASE, &vpit_regs);
+
+	/* Write Attribute Controller */
+	for (i = 0; i < 0x14; i++) {
+		reg_value = vga_r(VGABASE, VGA_IS1_RC);
+		vga_w(VGABASE, VGA_ATT_W, i);
+		vga_w(VGABASE, VGA_ATT_W, ar[i]);
+	}
+
+	/* Disable changing the palette registers */
+	reg_value = vga_r(VGABASE, VGA_IS1_RC);
+	vga_w(VGABASE, VGA_ATT_W, BIT(5));
+}
+
+static int via_iga1_display_fifo_regs(struct drm_device *dev,
+					struct via_drm_priv *dev_priv,
+					struct via_crtc *iga,
+					struct drm_display_mode *mode,
+					struct drm_framebuffer *fb)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	u32 reg_value;
+	unsigned int fifo_max_depth = 0;
+	unsigned int fifo_threshold = 0;
+	unsigned int fifo_high_threshold = 0;
+	unsigned int display_queue_expire_num = 0;
+	bool enable_extended_display_fifo = false;
+	int ret = 0;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_VIA_CLE266:
+		if (dev_priv->revision == CLE266_REVISION_AX) {
+			if (mode->hdisplay > 1024) {
+				/* SR17[6:0] */
+				fifo_max_depth = 96;
+
+				/* SR16[5:0] */
+				fifo_threshold = 92;
+
+				/* SR18[5:0] */
+				fifo_high_threshold = 92;
+
+				enable_extended_display_fifo = true;
+			} else {
+				/* SR17[6:0] */
+				fifo_max_depth = 64;
+
+				/* SR16[5:0] */
+				fifo_threshold = 32;
+
+				/* SR18[5:0] */
+				fifo_high_threshold = 56;
+
+				enable_extended_display_fifo = false;
+			}
+
+			if (dev_priv->vram_type <= VIA_MEM_DDR_200) {
+				if (fb->format->depth == 24) {
+					if (mode->hdisplay > 1024) {
+						if (mode->vdisplay > 768) {
+							/* SR22[4:0] */
+							display_queue_expire_num = 16;
+						} else {
+							/* SR22[4:0] */
+							display_queue_expire_num = 12;
+						}
+					} else if (mode->hdisplay > 640) {
+						/* SR22[4:0] */
+						display_queue_expire_num = 40;
+					} else {
+						/* SR22[4:0] */
+						display_queue_expire_num = 124;
+					}
+				} else if (fb->format->depth == 16){
+					if (mode->hdisplay > 1400) {
+						/* SR22[4:0] */
+						display_queue_expire_num = 16;
+					} else {
+						/* SR22[4:0] */
+						display_queue_expire_num = 12;
+					}
+				} else {
+					/* SR22[4:0] */
+					display_queue_expire_num = 124;
+				}
+			} else {
+				if (mode->hdisplay > 1280) {
+					/* SR22[4:0] */
+					display_queue_expire_num = 16;
+				} else if (mode->hdisplay > 1024) {
+					/* SR22[4:0] */
+					display_queue_expire_num = 12;
+				} else {
+					/* SR22[4:0] */
+					display_queue_expire_num = 124;
+				}
+			}
+		/* dev_priv->revision == CLE266_REVISION_CX */
+		} else {
+			if (mode->hdisplay >= 1024) {
+				/* SR17[6:0] */
+				fifo_max_depth = 128;
+
+				/* SR16[5:0] */
+				fifo_threshold = 112;
+
+				/* SR18[5:0] */
+				fifo_high_threshold = 92;
+
+				enable_extended_display_fifo = false;
+			} else {
+				/* SR17[6:0] */
+				fifo_max_depth = 64;
+
+				/* SR16[5:0] */
+				fifo_threshold = 32;
+
+				/* SR18[5:0] */
+				fifo_high_threshold = 56;
+
+				enable_extended_display_fifo = false;
+			}
+
+			if (dev_priv->vram_type <= VIA_MEM_DDR_200) {
+				if (mode->hdisplay > 1024) {
+					if (mode->vdisplay > 768) {
+						/* SR22[4:0] */
+						display_queue_expire_num = 16;
+					} else {
+						/* SR22[4:0] */
+						display_queue_expire_num = 12;
+					}
+				} else if (mode->hdisplay > 640) {
+					/* SR22[4:0] */
+					display_queue_expire_num = 40;
+				} else {
+					/* SR22[4:0] */
+					display_queue_expire_num = 124;
+				}
+			} else {
+				if (mode->hdisplay >= 1280) {
+					/* SR22[4:0] */
+					display_queue_expire_num = 16;
+				} else {
+					/* SR22[4:0] */
+					display_queue_expire_num = 124;
+				}
+			}
+		}
+		break;
+
+	case PCI_DEVICE_ID_VIA_KM400:
+		if ((mode->hdisplay >= 1600) &&
+			(dev_priv->vram_type <= VIA_MEM_DDR_200)) {
+			/* SR17[6:0] */
+			fifo_max_depth = 58;
+
+			/* SR16[5:0] */
+			fifo_threshold = 24;
+
+			/* SR18[5:0] */
+			fifo_high_threshold = 92;
+		} else {
+			/* SR17[6:0] */
+			fifo_max_depth = 128;
+
+			/* SR16[5:0] */
+			fifo_threshold = 112;
+
+			/* SR18[5:0] */
+			fifo_high_threshold = 92;
+		}
+
+		enable_extended_display_fifo = false;
+
+		if (dev_priv->vram_type <= VIA_MEM_DDR_200) {
+			if (mode->hdisplay >= 1600) {
+				/* SR22[4:0] */
+				display_queue_expire_num = 16;
+			} else {
+				/* SR22[4:0] */
+				display_queue_expire_num = 8;
+			}
+		} else {
+			if (mode->hdisplay >= 1600) {
+				/* SR22[4:0] */
+				display_queue_expire_num = 40;
+			} else {
+				/* SR22[4:0] */
+				display_queue_expire_num = 36;
+			}
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_K8M800:
+		/* SR17[7:0] */
+		fifo_max_depth = 384;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = 328;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = 296;
+
+		if ((fb->format->depth == 24) &&
+			(mode->hdisplay >= 1400)) {
+			/* SR22[4:0] */
+			display_queue_expire_num = 64;
+		} else {
+			/* SR22[4:0] */
+			display_queue_expire_num = 128;
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_PM800:
+		/* SR17[7:0] */
+		fifo_max_depth = 192;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = 128;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = 64;
+
+		if ((fb->format->depth == 24) &&
+			(mode->hdisplay >= 1400)) {
+			/* SR22[4:0] */
+			display_queue_expire_num = 64;
+		} else {
+			/* SR22[4:0] */
+			display_queue_expire_num = 124;
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_CN700:
+		/* SR17[7:0] */
+		fifo_max_depth = CN700_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = CN700_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = CN700_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = CN700_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* CX700 */
+	case PCI_DEVICE_ID_VIA_VT3157:
+		/* SR17[7:0] */
+		fifo_max_depth = CX700_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = CX700_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = CX700_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = CX700_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+
+		/* K8M890 */
+	case PCI_DEVICE_ID_VIA_K8M890:
+		/* SR17[7:0] */
+		fifo_max_depth = K8M890_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = K8M890_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = K8M890_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = K8M890_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* P4M890 */
+	case PCI_DEVICE_ID_VIA_VT3343:
+		/* SR17[7:0] */
+		fifo_max_depth = P4M890_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = P4M890_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = P4M890_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = P4M890_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* P4M900 */
+	case PCI_DEVICE_ID_VIA_P4M900:
+		/* SR17[7:0] */
+		fifo_max_depth = P4M900_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = P4M900_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = P4M900_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = P4M900_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* VX800 */
+	case PCI_DEVICE_ID_VIA_VT1122:
+		/* SR17[7:0] */
+		fifo_max_depth = VX800_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = VX800_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = VX800_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = VX800_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* VX855 */
+	case PCI_DEVICE_ID_VIA_VX875:
+		/* SR17[7:0] */
+		fifo_max_depth = VX855_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = VX855_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = VX855_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = VX855_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* VX900 */
+	case PCI_DEVICE_ID_VIA_VX900_VGA:
+		/* SR17[7:0] */
+		fifo_max_depth = VX900_IGA1_FIFO_MAX_DEPTH;
+
+		/* SR16[7], SR16[5:0] */
+		fifo_threshold = VX900_IGA1_FIFO_THRESHOLD;
+
+		/* SR18[7], SR18[5:0] */
+		fifo_high_threshold = VX900_IGA1_FIFO_HIGH_THRESHOLD;
+
+		/* SR22[4:0] */
+		display_queue_expire_num = VX900_IGA1_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret) {
+		goto exit;
+	}
+
+	if ((pdev->device == PCI_DEVICE_ID_VIA_CLE266) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_KM400) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_K8M800) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_PM800) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_CN700) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_VT3157)) {
+		/* Force PREQ to be always higher than TREQ. */
+		svga_wseq_mask(VGABASE, 0x18, BIT(6), BIT(6));
+	} else {
+		svga_wseq_mask(VGABASE, 0x18, 0x00, BIT(6));
+	}
+
+	if ((pdev->device == PCI_DEVICE_ID_VIA_CLE266) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_KM400)) {
+		if (enable_extended_display_fifo) {
+			reg_value = VIA_READ(0x0298);
+			VIA_WRITE(0x0298, reg_value | 0x20000000);
+
+			/* Turn on IGA1 extended display FIFO. */
+			reg_value = VIA_READ(0x0230);
+			VIA_WRITE(0x0230, reg_value | 0x00200000);
+
+			reg_value = VIA_READ(0x0298);
+			VIA_WRITE(0x0298, reg_value & (~0x20000000));
+		} else {
+			reg_value = VIA_READ(0x0298);
+			VIA_WRITE(0x0298, reg_value | 0x20000000);
+
+			/* Turn off IGA1 extended display FIFO. */
+			reg_value = VIA_READ(0x0230);
+			VIA_WRITE(0x0230, reg_value & (~0x00200000));
+
+			reg_value = VIA_READ(0x0298);
+			VIA_WRITE(0x0298, reg_value & (~0x20000000));
+
+		}
+	}
+
+	/* Set IGA1 Display FIFO Depth Select */
+	reg_value = IGA1_FIFO_DEPTH_SELECT_FORMULA(fifo_max_depth);
+	load_value_to_registers(VGABASE, &iga->fifo_depth, reg_value);
+
+	/* Set Display FIFO Threshold Select */
+	reg_value = fifo_threshold / 4;
+	load_value_to_registers(VGABASE, &iga->threshold, reg_value);
+
+	/* Set FIFO High Threshold Select */
+	reg_value = fifo_high_threshold / 4;
+	load_value_to_registers(VGABASE, &iga->high_threshold, reg_value);
+
+	/* Set Display Queue Expire Num */
+	reg_value = display_queue_expire_num / 4;
+	load_value_to_registers(VGABASE, &iga->display_queue, reg_value);
+
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return ret;
+}
+
+static int via_iga2_display_fifo_regs(struct drm_device *dev,
+					struct via_drm_priv *dev_priv,
+					struct via_crtc *iga,
+					struct drm_display_mode *mode,
+					struct drm_framebuffer *fb)
+{
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	u32 reg_value;
+	unsigned int fifo_max_depth = 0;
+	unsigned int fifo_threshold = 0;
+	unsigned int fifo_high_threshold = 0;
+	unsigned int display_queue_expire_num = 0;
+	bool enable_extended_display_fifo = false;
+	int ret = 0;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	switch (pdev->device) {
+	case PCI_DEVICE_ID_VIA_CLE266:
+		if (dev_priv->revision == CLE266_REVISION_AX) {
+			if (((dev_priv->vram_type <= VIA_MEM_DDR_200) &&
+				(fb->format->depth > 16) &&
+				(mode->vdisplay > 768)) ||
+				((dev_priv->vram_type <= VIA_MEM_DDR_266) &&
+				(fb->format->depth > 16) &&
+				(mode->hdisplay > 1280))) {
+				/* CR68[7:4] */
+				fifo_max_depth = 88;
+
+				/* CR68[3:0] */
+				fifo_threshold = 44;
+
+				enable_extended_display_fifo = true;
+			} else {
+				/* CR68[7:4] */
+				fifo_max_depth = 56;
+
+				/* CR68[3:0] */
+				fifo_threshold = 28;
+
+				enable_extended_display_fifo = false;
+			}
+		/* dev_priv->revision == CLE266_REVISION_CX */
+		} else {
+			if (mode->hdisplay >= 1024) {
+				/* CR68[7:4] */
+				fifo_max_depth = 88;
+
+				/* CR68[3:0] */
+				fifo_threshold = 44;
+
+				enable_extended_display_fifo = false;
+			} else {
+				/* CR68[7:4] */
+				fifo_max_depth = 56;
+
+				/* CR68[3:0] */
+				fifo_threshold = 28;
+
+				enable_extended_display_fifo = false;
+			}
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_KM400:
+		if (mode->hdisplay >= 1600) {
+			/* CR68[7:4] */
+			fifo_max_depth = 120;
+
+			/* CR68[3:0] */
+			fifo_threshold = 44;
+
+			enable_extended_display_fifo = true;
+		} else if (((mode->hdisplay > 1024) &&
+			(fb->format->depth == 24) &&
+			(dev_priv->vram_type <= VIA_MEM_DDR_333)) ||
+			((mode->hdisplay == 1024) &&
+			(fb->format->depth == 24) &&
+			(dev_priv->vram_type <= VIA_MEM_DDR_200))) {
+			/* CR68[7:4] */
+			fifo_max_depth = 104;
+
+			/* CR68[3:0] */
+			fifo_threshold = 28;
+
+			enable_extended_display_fifo = true;
+		} else if (((mode->hdisplay > 1280) &&
+			(fb->format->depth == 16) &&
+			(dev_priv->vram_type <= VIA_MEM_DDR_333)) ||
+			((mode->hdisplay == 1280) &&
+			(fb->format->depth == 16) &&
+			(dev_priv->vram_type <= VIA_MEM_DDR_200))) {
+			/* CR68[7:4] */
+			fifo_max_depth = 88;
+
+			/* CR68[3:0] */
+			fifo_threshold = 44;
+
+			enable_extended_display_fifo = true;
+		} else {
+			/* CR68[7:4] */
+			fifo_max_depth = 56;
+
+			/* CR68[3:0] */
+			fifo_threshold = 28;
+
+			enable_extended_display_fifo = false;
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_K8M800:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = 376;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = 328;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = 296;
+
+		if ((fb->format->depth == 24) &&
+			(mode->hdisplay >= 1400)) {
+			/* CR94[6:0] */
+			display_queue_expire_num = 64;
+		} else {
+			/* CR94[6:0] */
+			display_queue_expire_num = 128;
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_PM800:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = 96;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = 64;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = 32;
+
+		if ((fb->format->depth == 24) &&
+				(mode->hdisplay >= 1400)) {
+			/* CR94[6:0] */
+			display_queue_expire_num = 64;
+		} else {
+			/* CR94[6:0] */
+			display_queue_expire_num = 128;
+		}
+
+		break;
+	case PCI_DEVICE_ID_VIA_CN700:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = CN700_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = CN700_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = CN700_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = CN700_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* CX700 */
+	case PCI_DEVICE_ID_VIA_VT3157:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = CX700_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = CX700_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = CX700_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = CX700_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+
+		/* K8M890 */
+	case PCI_DEVICE_ID_VIA_K8M890:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = K8M890_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = K8M890_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = K8M890_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = K8M890_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* P4M890 */
+	case PCI_DEVICE_ID_VIA_VT3343:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = P4M890_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = P4M890_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = P4M890_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = P4M890_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* P4M900 */
+	case PCI_DEVICE_ID_VIA_P4M900:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = P4M900_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_threshold = P4M900_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = P4M900_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = P4M900_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* VX800 */
+	case PCI_DEVICE_ID_VIA_VT1122:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = VX800_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = VX800_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = VX800_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = VX800_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* VX855 */
+	case PCI_DEVICE_ID_VIA_VX875:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = VX855_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = VX855_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = VX855_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = VX855_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+		/* VX900 */
+	case PCI_DEVICE_ID_VIA_VX900_VGA:
+		/* CR95[7], CR94[7], CR68[7:4] */
+		fifo_max_depth = VX900_IGA2_FIFO_MAX_DEPTH;
+
+		/* CR95[6:4], CR68[3:0] */
+		fifo_threshold = VX900_IGA2_FIFO_THRESHOLD;
+
+		/* CR95[2:0], CR92[3:0] */
+		fifo_high_threshold = VX900_IGA2_FIFO_HIGH_THRESHOLD;
+
+		/* CR94[6:0] */
+		display_queue_expire_num = VX900_IGA2_DISPLAY_QUEUE_EXPIRE_NUM;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret) {
+		goto exit;
+	}
+
+	if ((pdev->device == PCI_DEVICE_ID_VIA_CLE266) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_KM400)) {
+		if (enable_extended_display_fifo) {
+			/* Enable IGA2 extended display FIFO. */
+			svga_wcrt_mask(VGABASE, 0x6a, BIT(5), BIT(5));
+		} else {
+			/* Disable IGA2 extended display FIFO. */
+			svga_wcrt_mask(VGABASE, 0x6a, 0x00, BIT(5));
+		}
+	}
+
+	if ((pdev->device == PCI_DEVICE_ID_VIA_CLE266) ||
+		(pdev->device == PCI_DEVICE_ID_VIA_KM400)) {
+		/* Set IGA2 Display FIFO Depth Select */
+		reg_value = IGA2_FIFO_DEPTH_SELECT_FORMULA(fifo_max_depth);
+		load_value_to_registers(VGABASE, &iga->fifo_depth, reg_value);
+
+		/* Set Display FIFO Threshold Select */
+		reg_value = fifo_threshold / 4;
+		load_value_to_registers(VGABASE, &iga->threshold, reg_value);
+	} else {
+		/* Set IGA2 Display FIFO Depth Select */
+		reg_value = IGA2_FIFO_DEPTH_SELECT_FORMULA(fifo_max_depth);
+		load_value_to_registers(VGABASE, &iga->fifo_depth, reg_value);
+
+		/* Set Display FIFO Threshold Select */
+		reg_value = fifo_threshold / 4;
+		load_value_to_registers(VGABASE, &iga->threshold, reg_value);
+
+		/* Set FIFO High Threshold Select */
+		reg_value = fifo_high_threshold / 4;
+		load_value_to_registers(VGABASE, &iga->high_threshold, reg_value);
+
+		/* Set Display Queue Expire Num */
+		reg_value = display_queue_expire_num / 4;
+		load_value_to_registers(VGABASE, &iga->display_queue, reg_value);
+	}
+
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return ret;
+}
+
+/* Load CRTC Pixel Timing registers */
+void via_load_crtc_pixel_timing(struct drm_crtc *crtc,
+				struct drm_display_mode *mode)
+{
+	struct drm_device *dev = crtc->dev;
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	u32 reg_value = 0;
+
+	reg_value = IGA1_PIXELTIMING_HOR_TOTAL_FORMULA(mode->crtc_htotal);
+	load_value_to_registers(VGABASE, &iga->pixel_timings.htotal,
+				reg_value);
+
+	reg_value = IGA1_PIXELTIMING_HOR_ADDR_FORMULA(mode->crtc_hdisplay) << 16;
+	load_value_to_registers(VGABASE, &iga->pixel_timings.hdisplay,
+				reg_value);
+
+	reg_value = IGA1_PIXELTIMING_HOR_BLANK_START_FORMULA(
+					mode->crtc_hblank_start);
+	load_value_to_registers(VGABASE, &iga->pixel_timings.hblank_start,
+				reg_value);
+
+	reg_value = IGA1_PIXELTIMING_HOR_BLANK_END_FORMULA(mode->crtc_hblank_end) << 16;
+	load_value_to_registers(VGABASE, &iga->pixel_timings.hblank_end, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_HOR_SYNC_START_FORMULA(mode->crtc_hsync_start);
+	load_value_to_registers(VGABASE, &iga->pixel_timings.hsync_start,
+				reg_value);
+
+	reg_value = IGA1_PIXELTIMING_HOR_SYNC_END_FORMULA(mode->crtc_hsync_end) << 16;
+	load_value_to_registers(VGABASE, &iga->pixel_timings.hsync_end, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_VER_TOTAL_FORMULA(mode->crtc_vtotal);
+	load_value_to_registers(VGABASE, &iga->pixel_timings.vtotal, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_VER_ADDR_FORMULA(mode->crtc_vdisplay) << 16;
+	load_value_to_registers(VGABASE, &iga->pixel_timings.vdisplay, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_VER_BLANK_START_FORMULA(
+					mode->crtc_vblank_start);
+	load_value_to_registers(VGABASE, &iga->pixel_timings.vblank_start, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_VER_BLANK_END_FORMULA(mode->crtc_vblank_end) << 16;
+	load_value_to_registers(VGABASE, &iga->pixel_timings.vblank_end, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_VER_SYNC_START_FORMULA(mode->crtc_vsync_start);
+	load_value_to_registers(VGABASE, &iga->pixel_timings.vsync_start, reg_value);
+
+	reg_value = IGA1_PIXELTIMING_VER_SYNC_END_FORMULA(mode->crtc_vsync_end) << 12;
+	load_value_to_registers(VGABASE, &iga->pixel_timings.vsync_end, reg_value);
+
+	if (mode->flags & DRM_MODE_FLAG_INTERLACE) {
+		reg_value = IGA1_PIXELTIMING_HVSYNC_OFFSET_END_FORMULA(
+				mode->crtc_htotal, mode->crtc_hsync_start);
+		VIA_WRITE_MASK(IGA1_PIX_HALF_LINE_REG, reg_value,
+					IGA1_PIX_HALF_LINE_MASK);
+
+		svga_wcrt_mask(VGABASE, 0x32, BIT(2), BIT(2));
+		/**
+		 * According to information from HW team,
+		 * we need to set 0xC280[1] = 1 (HDMI function enable)
+		 * or 0xC640[0] = 1 (DP1 enable)
+		 * to let the half line function work.
+		 * Otherwise, the clock for interlace mode
+		 * will not correct.
+		 * This is a special setting for 410.
+		 */
+		VIA_WRITE_MASK(0xC280, BIT(1), BIT(1));
+	} else {
+		VIA_WRITE_MASK(IGA1_PIX_HALF_LINE_REG, 0x0, IGA1_PIX_HALF_LINE_MASK);
+		svga_wcrt_mask(VGABASE, 0x32, 0x00, BIT(2));
+
+	}
+	svga_wcrt_mask(VGABASE, 0xFD, BIT(5), BIT(5));
+}
+
+/* Load CRTC timing registers */
+void via_load_crtc_timing(struct via_crtc *iga, struct drm_display_mode *mode)
+{
+	struct drm_device *dev = iga->base.dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	u32 reg_value = 0;
+
+	if (!iga->index) {
+		if (pdev->device == PCI_DEVICE_ID_VIA_VX900_VGA) {
+			/* Disable IGA1 shadow timing */
+			svga_wcrt_mask(VGABASE, 0x45, 0x00, BIT(0));
+
+			/* Disable IGA1 pixel timing */
+			svga_wcrt_mask(VGABASE, 0xFD, 0x00, BIT(5));
+		}
+
+		reg_value = IGA1_HOR_TOTAL_FORMULA(mode->crtc_htotal);
+		load_value_to_registers(VGABASE, &iga->timings.htotal, reg_value);
+
+		reg_value = IGA1_HOR_ADDR_FORMULA(mode->crtc_hdisplay);
+		load_value_to_registers(VGABASE, &iga->timings.hdisplay, reg_value);
+
+		reg_value = IGA1_HOR_BLANK_START_FORMULA(mode->crtc_hblank_start);
+		load_value_to_registers(VGABASE, &iga->timings.hblank_start, reg_value);
+
+		reg_value = IGA1_HOR_BLANK_END_FORMULA(mode->crtc_hblank_end);
+		load_value_to_registers(VGABASE, &iga->timings.hblank_end, reg_value);
+
+		reg_value = IGA1_HOR_SYNC_START_FORMULA(mode->crtc_hsync_start);
+		load_value_to_registers(VGABASE, &iga->timings.hsync_start, reg_value);
+
+		reg_value = IGA1_HOR_SYNC_END_FORMULA(mode->crtc_hsync_end);
+		load_value_to_registers(VGABASE, &iga->timings.hsync_end, reg_value);
+
+		reg_value = IGA1_VER_TOTAL_FORMULA(mode->crtc_vtotal);
+		load_value_to_registers(VGABASE, &iga->timings.vtotal, reg_value);
+
+		reg_value = IGA1_VER_ADDR_FORMULA(mode->crtc_vdisplay);
+		load_value_to_registers(VGABASE, &iga->timings.vdisplay, reg_value);
+
+		reg_value = IGA1_VER_BLANK_START_FORMULA(mode->crtc_vblank_start);
+		load_value_to_registers(VGABASE, &iga->timings.vblank_start, reg_value);
+
+		reg_value = IGA1_VER_BLANK_END_FORMULA(mode->crtc_vblank_end);
+		load_value_to_registers(VGABASE, &iga->timings.vblank_end, reg_value);
+
+		reg_value = IGA1_VER_SYNC_START_FORMULA(mode->crtc_vsync_start);
+		load_value_to_registers(VGABASE, &iga->timings.vsync_start, reg_value);
+
+		reg_value = IGA1_VER_SYNC_END_FORMULA(mode->crtc_vsync_end);
+		load_value_to_registers(VGABASE, &iga->timings.vsync_end, reg_value);
+	} else {
+		reg_value = IGA2_HOR_TOTAL_FORMULA(mode->crtc_htotal);
+		load_value_to_registers(VGABASE, &iga->timings.htotal, reg_value);
+
+		reg_value = IGA2_HOR_ADDR_FORMULA(mode->crtc_hdisplay);
+		load_value_to_registers(VGABASE, &iga->timings.hdisplay, reg_value);
+
+		reg_value = IGA2_HOR_BLANK_START_FORMULA(mode->crtc_hblank_start);
+		load_value_to_registers(VGABASE, &iga->timings.hblank_start, reg_value);
+
+		reg_value = IGA2_HOR_BLANK_END_FORMULA(mode->crtc_hblank_end);
+		load_value_to_registers(VGABASE, &iga->timings.hblank_end, reg_value);
+
+		reg_value = IGA2_HOR_SYNC_START_FORMULA(mode->crtc_hsync_start);
+		load_value_to_registers(VGABASE, &iga->timings.hsync_start, reg_value);
+
+		reg_value = IGA2_HOR_SYNC_END_FORMULA(mode->crtc_hsync_end);
+		load_value_to_registers(VGABASE, &iga->timings.hsync_end, reg_value);
+
+		reg_value = IGA2_VER_TOTAL_FORMULA(mode->crtc_vtotal);
+		load_value_to_registers(VGABASE, &iga->timings.vtotal, reg_value);
+
+		reg_value = IGA2_VER_ADDR_FORMULA(mode->crtc_vdisplay);
+		load_value_to_registers(VGABASE, &iga->timings.vdisplay, reg_value);
+
+		reg_value = IGA2_VER_BLANK_START_FORMULA(mode->crtc_vblank_start);
+		load_value_to_registers(VGABASE, &iga->timings.vblank_start, reg_value);
+
+		reg_value = IGA2_VER_BLANK_END_FORMULA(mode->crtc_vblank_end);
+		load_value_to_registers(VGABASE, &iga->timings.vblank_end, reg_value);
+
+		reg_value = IGA2_VER_SYNC_START_FORMULA(mode->crtc_vsync_start);
+		load_value_to_registers(VGABASE, &iga->timings.vsync_start, reg_value);
+
+		reg_value = IGA2_VER_SYNC_END_FORMULA(mode->crtc_vsync_end);
+		load_value_to_registers(VGABASE, &iga->timings.vsync_end, reg_value);
+	}
+}
+
+/*
+ * This function changes the destination of scaling up/down
+ * and CRTC timing registers
+ * crtc : which IGA
+ * scale_type : upscaling(VIA_EXPAND) or downscaling(VIA_SHRINK)
+ */
+void via_set_scale_path(struct drm_crtc *crtc, u32 scale_type)
+{
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+	struct drm_device *dev = crtc->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	u8 reg_cr_fd = vga_rcrt(VGABASE, 0xFD);
+
+	if (!iga->index)
+		/* register reuse: select IGA1 path */
+		reg_cr_fd |= BIT(7);
+	else
+		/* register reuse: select IGA2 path */
+		reg_cr_fd &= ~BIT(7);
+
+	/* only IGA1 up scaling need to clear this bit CRFD.5. */
+	if (pdev->device == PCI_DEVICE_ID_VIA_VX900_VGA) {
+		if (!iga->index
+			&& ((VIA_HOR_EXPAND & scale_type)
+			|| (VIA_VER_EXPAND & scale_type)))
+			reg_cr_fd &= ~BIT(5);
+	}
+
+	/* CRFD.0 = 0 : common IGA2, = 1 : downscaling IGA */
+	switch (scale_type) {
+	case VIA_NO_SCALING:
+	case VIA_EXPAND:
+	case VIA_HOR_EXPAND:
+	case VIA_VER_EXPAND:
+		/* register reuse: as common IGA2 */
+		reg_cr_fd &= ~BIT(0);
+		break;
+
+	case VIA_SHRINK:
+		/* register reuse: as downscaling IGA */
+		reg_cr_fd |= BIT(0);
+		break;
+
+	default:
+		break;
+	}
+	vga_wcrt(VGABASE, 0xFD, reg_cr_fd);
+}
+
+/* disable IGA scaling */
+static void via_disable_iga_scaling(struct drm_crtc *crtc)
+{
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+	struct drm_device *dev = crtc->dev;
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+
+	if (iga->index) {
+		/* IGA2 scalings disable */
+		via_set_scale_path(crtc, VIA_SHRINK);
+		/* disable IGA down scaling and buffer sharing. */
+		svga_wcrt_mask(VGABASE, 0x89, 0x00, BIT(7) | BIT(0));
+		/* Horizontal and Vertical scaling disable */
+		svga_wcrt_mask(VGABASE, 0xA2, 0x00, BIT(7) | BIT(3));
+
+		/* Disable scale up as well */
+		via_set_scale_path(crtc, VIA_EXPAND);
+		/* disable IGA up scaling */
+		svga_wcrt_mask(VGABASE, 0x79, 0, BIT(0));
+		/* Horizontal and Vertical scaling disable */
+		svga_wcrt_mask(VGABASE, 0xA2, 0x00, BIT(7) | BIT(3));
+	} else {
+		/* IGA1 scalings disable */
+		via_set_scale_path(crtc, VIA_SHRINK);
+		/* disable IGA down scaling and buffer sharing. */
+		svga_wcrt_mask(VGABASE, 0x89, 0x00, BIT(7) | BIT(0));
+		/* Horizontal and Vertical scaling disable */
+		svga_wcrt_mask(VGABASE, 0xA2, 0x00, BIT(7) | BIT(3));
+
+		/* Disable scale up as well */
+		via_set_scale_path(crtc, VIA_EXPAND);
+		/* disable IGA up scaling */
+		svga_wcrt_mask(VGABASE, 0x79, 0, BIT(0));
+		/* Horizontal and Vertical scaling disable */
+		svga_wcrt_mask(VGABASE, 0xA2, 0x00, BIT(7) | BIT(3));
+	}
+}
+
+/*
+ * Enable IGA scale functions.
+ *
+ * input : iga_path =	IGA1 or IGA2 or
+ *			IGA1+IGA2
+ *
+ * scale_type	=	VIA_HOR_EXPAND or VIA_VER_EXPAND or VIA_EXPAND or
+ *			VIA_SHRINK or VIA_SHRINK + VIA_EXPAND
+ */
+bool via_set_iga_scale_function(struct drm_crtc *crtc, u32 scale_type)
+{
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+	struct drm_device *dev = crtc->dev;
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+
+	if (!(scale_type & (VIA_SHRINK + VIA_EXPAND)))
+		return false;
+
+	if (iga->index) {
+		/* IGA2 scalings enable */
+		if (VIA_SHRINK & scale_type) {
+			via_set_scale_path(crtc, VIA_SHRINK);
+			/* Horizontal and Vertical scaling enable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7) | BIT(3), BIT(7) | BIT(3));
+			/* enable IGA down scaling */
+			svga_wcrt_mask(VGABASE, 0x89, BIT(0), BIT(0));
+			/* hor and ver scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(2) | BIT(1), BIT(2) | BIT(1));
+		}
+
+		if (VIA_EXPAND & scale_type) {
+			via_set_scale_path(crtc, VIA_EXPAND);
+			/* enable IGA up scaling */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(0), BIT(0));
+		}
+
+		if ((VIA_EXPAND & scale_type) == VIA_EXPAND) {
+			/* Horizontal and Vertical scaling enable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7) | BIT(3), BIT(7) | BIT(3));
+			/* hor and ver scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(2) | BIT(1), BIT(2) | BIT(1));
+		} else if (VIA_HOR_EXPAND & scale_type) {
+			/* Horizontal scaling disable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7), BIT(7));
+			/* hor scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(1), BIT(1));
+		} else if (VIA_VER_EXPAND & scale_type) {
+			/* Vertical scaling disable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(3), BIT(3));
+			/* ver scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(2), BIT(2));
+		}
+	} else {
+		/* IGA1 scalings enable */
+		if (VIA_SHRINK & scale_type) {
+			via_set_scale_path(crtc, VIA_SHRINK);
+
+			/* Horizontal and Vertical scaling enable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7) | BIT(3), BIT(7) | BIT(3));
+			/* enable IGA down scaling */
+			svga_wcrt_mask(VGABASE, 0x89, BIT(0), BIT(0));
+			/* hor and ver scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(2) | BIT(1), BIT(2) | BIT(1));
+		}
+
+		if (VIA_EXPAND & scale_type) {
+			via_set_scale_path(crtc, VIA_EXPAND);
+			/* enable IGA up scaling */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(0), BIT(0));
+		}
+
+		if ((VIA_EXPAND & scale_type) == VIA_EXPAND) {
+			/* Horizontal and Vertical scaling enable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7) | BIT(3), BIT(7) | BIT(3));
+			/* hor and ver scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(2) | BIT(1), BIT(2) | BIT(1));
+		} else if (VIA_HOR_EXPAND & scale_type) {
+			/* Horizontal scaling disable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7), BIT(7));
+			/* hor scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(1), BIT(1));
+		} else if (VIA_VER_EXPAND & scale_type) {
+			/* Vertical scaling disable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(3), BIT(3));
+			/* ver scaling : Interpolation */
+			svga_wcrt_mask(VGABASE, 0x79, BIT(2), BIT(2));
+		}
+	}
+	return true;
+}
+
+/*
+ * 1. get scale factors from source and dest H & V size
+ * 2. load scale factors into registers
+ * 3. enable H or V scale ( set CRA2 bit7 or bit3 )
+ */
+bool via_load_iga_scale_factor_regs(struct via_drm_priv *dev_priv,
+					struct drm_display_mode *mode,
+					struct drm_display_mode *adjusted_mode,
+					u32 scale_type, u32 is_hor_or_ver)
+{
+	u32 dst_hor_regs = adjusted_mode->crtc_hdisplay;
+	u32 dst_ver_regs = adjusted_mode->crtc_vdisplay;
+	u32 src_hor_regs = mode->crtc_hdisplay;
+	u32 src_ver_regs = mode->crtc_vdisplay;
+	u32 hor_factor = 0, ver_factor = 0;
+	struct vga_registers reg;
+
+	if ((0 == src_hor_regs) || (0 == src_ver_regs) || (0 == dst_hor_regs)
+			|| (0 == dst_ver_regs))
+		return false;
+
+	if (VIA_EXPAND == scale_type) {
+		if (HOR_SCALE & is_hor_or_ver) {
+			hor_factor = ((src_hor_regs - 1) * 4096) / (dst_hor_regs - 1);
+			reg.count = ARRAY_SIZE(lcd_hor_scaling);
+			reg.regs = lcd_hor_scaling;
+			load_value_to_registers(VGABASE, &reg, hor_factor);
+			/* Horizontal scaling enable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7), BIT(7));
+		}
+
+		if (VER_SCALE & is_hor_or_ver) {
+			ver_factor = ((src_ver_regs - 1) * 2048) / (dst_ver_regs - 1);
+			reg.count = ARRAY_SIZE(lcd_ver_scaling);
+			reg.regs = lcd_ver_scaling;
+			load_value_to_registers(VGABASE, &reg, ver_factor);
+			/* Vertical scaling enable */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(3), BIT(3));
+		}
+
+	} else if (VIA_SHRINK == scale_type) {
+
+		if (src_hor_regs > dst_hor_regs)
+			hor_factor = ((src_hor_regs - dst_hor_regs) * 4096) / dst_hor_regs;
+
+		if (src_ver_regs > dst_ver_regs)
+			ver_factor = ((src_ver_regs - dst_ver_regs) * 2048) / dst_ver_regs;
+
+		reg.count = ARRAY_SIZE(lcd_hor_scaling);
+		reg.regs = lcd_hor_scaling;
+		load_value_to_registers(VGABASE, &reg, hor_factor);
+
+		reg.count = ARRAY_SIZE(lcd_ver_scaling);
+		reg.regs = lcd_ver_scaling;
+		load_value_to_registers(VGABASE, &reg, ver_factor);
+
+		/* set buffer sharing enable bit . */
+		if (hor_factor || ver_factor) {
+			if (dst_hor_regs > 1024)
+				svga_wcrt_mask(VGABASE, 0x89, BIT(7), BIT(7));
+			else
+				svga_wcrt_mask(VGABASE, 0x89, 0x00, BIT(7));
+		}
+
+		if (hor_factor)
+			/* CRA2[7]:1 Enable Hor scaling
+			   CRA2[6]:1 Linear Mode */
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(7) | BIT(6), BIT(7) | BIT(6));
+		else
+			svga_wcrt_mask(VGABASE, 0xA2, 0, BIT(7));
+
+		if (ver_factor)
+			svga_wcrt_mask(VGABASE, 0xA2, BIT(3), BIT(3));
+		else
+			svga_wcrt_mask(VGABASE, 0xA2, 0, BIT(3));
+	}
+	return true;
+}
+
+void via_set_iga2_downscale_source_timing(struct drm_crtc *crtc,
+				struct drm_display_mode *mode,
+				struct drm_display_mode *adjusted_mode)
+{
+	unsigned int viewx = adjusted_mode->hdisplay,
+			viewy = adjusted_mode->vdisplay;
+	unsigned int srcx = mode->crtc_hdisplay, srcy = mode->crtc_vdisplay;
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+	struct drm_display_mode *src_timing;
+
+	src_timing = drm_mode_duplicate(crtc->dev, adjusted_mode);
+	/* derived source timing */
+	if (srcx <= viewx) {
+		src_timing->crtc_htotal = adjusted_mode->crtc_htotal;
+		src_timing->crtc_hdisplay = adjusted_mode->crtc_hdisplay;
+	} else {
+		unsigned int htotal = adjusted_mode->crtc_htotal -
+					adjusted_mode->crtc_hdisplay;
+
+		src_timing->crtc_htotal = htotal + srcx;
+		src_timing->crtc_hdisplay = srcx;
+	}
+	src_timing->crtc_hblank_start = src_timing->crtc_hdisplay;
+	src_timing->crtc_hblank_end = src_timing->crtc_htotal;
+	src_timing->crtc_hsync_start = src_timing->crtc_hdisplay + 2;
+	src_timing->crtc_hsync_end = src_timing->crtc_hsync_start + 1;
+
+	if (srcy <= viewy) {
+		src_timing->crtc_vtotal = adjusted_mode->crtc_vtotal;
+		src_timing->crtc_vdisplay = adjusted_mode->crtc_vdisplay;
+	} else {
+		unsigned int vtotal = adjusted_mode->crtc_vtotal -
+					adjusted_mode->crtc_vdisplay;
+
+		src_timing->crtc_vtotal = vtotal + srcy;
+		src_timing->crtc_vdisplay = srcy;
+	}
+	src_timing->crtc_vblank_start = src_timing->crtc_vdisplay;
+	src_timing->crtc_vblank_end = src_timing->crtc_vtotal;
+	src_timing->crtc_vsync_start = src_timing->crtc_vdisplay + 2;
+	src_timing->crtc_vsync_end = src_timing->crtc_vsync_start + 1;
+
+	via_set_scale_path(crtc, VIA_NO_SCALING);
+	/* load src timing */
+	via_load_crtc_timing(iga, src_timing);
+
+	/* Cleanup up source timings */
+	drm_mode_destroy(crtc->dev, src_timing);
+}
+
+void via_mode_set_nofb(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	struct drm_display_mode *mode = &crtc->state->mode;
+	struct drm_display_mode *adjusted_mode =
+					&crtc->state->adjusted_mode;
+	struct via_crtc *iga = container_of(crtc,
+						struct via_crtc, base);
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	u8 reg_value = 0;
+	int ret;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if (!iga->index) {
+		/* Load standard registers */
+		via_load_vpit_regs(dev_priv);
+
+		/* Unlock */
+		via_unlock_crtc(VGABASE, pdev->device);
+
+		/* IGA1 reset */
+		vga_wcrt(VGABASE, 0x09, 0x00); /* initial CR09=0 */
+		svga_wcrt_mask(VGABASE, 0x11, 0x00, BIT(6));
+
+		/* disable IGA scales first */
+		via_disable_iga_scaling(crtc);
+
+		/*
+		 * when not down scaling, we only need load one
+		 * timing.
+		 */
+		via_load_crtc_timing(iga, adjusted_mode);
+
+		switch (adjusted_mode->crtc_htotal % 8) {
+		case 0:
+		default:
+			break;
+		case 2:
+			reg_value = BIT(7);
+			break;
+		case 4:
+			reg_value = BIT(6);
+			break;
+		case 6:
+			reg_value = BIT(3);
+			break;
+		}
+
+		svga_wcrt_mask(VGABASE, 0x47,
+				reg_value, BIT(7) | BIT(6) | BIT(3));
+
+		/* Relock */
+		via_lock_crtc(VGABASE);
+
+		/* Set non-interlace / interlace mode. */
+		via_iga1_set_interlace_mode(VGABASE,
+					adjusted_mode->flags &
+					DRM_MODE_FLAG_INTERLACE);
+
+		/* No HSYNC shift. */
+		via_iga1_set_hsync_shift(VGABASE, 0x05);
+
+		/* Load display FIFO. */
+		ret = via_iga1_display_fifo_regs(dev, dev_priv,
+						iga, adjusted_mode,
+						crtc->primary->fb);
+		if (ret) {
+			goto exit;
+		}
+
+		/* Set PLL */
+		if (adjusted_mode->clock) {
+			u32 clock = adjusted_mode->clock * 1000;
+			u32 pll_regs;
+
+			if (iga->scaling_mode & VIA_SHRINK)
+				clock *= 2;
+			pll_regs = via_get_clk_value(crtc->dev, clock);
+			via_set_vclock(crtc, pll_regs);
+		}
+
+		via_iga_common_init(VGABASE);
+
+		/* Set palette LUT to 8-bit mode. */
+		via_iga1_set_palette_lut_resolution(VGABASE, true);
+	} else {
+		/* Load standard registers */
+		via_load_vpit_regs(dev_priv);
+
+		/* Unlock */
+		via_unlock_crtc(VGABASE, pdev->device);
+
+		/* disable IGA scales first */
+		via_disable_iga_scaling(crtc);
+
+		/* Load crtc timing and IGA scaling */
+		if (iga->scaling_mode & VIA_SHRINK) {
+			/*
+			 * enable IGA2 down scaling and set
+			 * Interpolation
+			 */
+			via_set_iga_scale_function(crtc, VIA_SHRINK);
+
+			/* load hor and ver downscaling factor */
+			/*
+			 * interlace modes scaling support(example
+			 * 1080I): we should use mode->crtc_vdisplay
+			 * here, because crtc_vdisplay=540,
+			 * vdisplay=1080, we need 540 here, not 1080.
+			 */
+			via_load_iga_scale_factor_regs(dev_priv,
+							mode,
+							adjusted_mode,
+							VIA_SHRINK,
+							HOR_VER_SCALE);
+			/* load src timing to timing registers */
+			/*
+			 * interlace modes scaling support(example
+			 * 1080I): we should use mode->crtc_vdisplay
+			 * here, because crtc_vdisplay=540,
+			 * vdisplay=1080, we need 540 here, not 1080.
+			 */
+			via_set_iga2_downscale_source_timing(crtc,
+							mode,
+							adjusted_mode);
+
+			/* Download dst timing */
+			via_set_scale_path(crtc, VIA_SHRINK);
+			via_load_crtc_timing(iga, adjusted_mode);
+			/*
+			 * very necessary to set IGA to none scaling
+			 * status need to fix why so need.
+			 */
+			via_set_scale_path(crtc, VIA_NO_SCALING);
+		} else {
+			/*
+			 * when not down scaling, we only need load
+			 * one timing.
+			 */
+			via_load_crtc_timing(iga, adjusted_mode);
+
+			/* II. up scaling */
+			if (iga->scaling_mode & VIA_EXPAND) {
+				/* Horizontal scaling */
+				if (iga->scaling_mode &
+					VIA_HOR_EXPAND) {
+					via_set_iga_scale_function(
+						crtc,
+						VIA_HOR_EXPAND);
+					via_load_iga_scale_factor_regs(
+							dev_priv,
+							mode,
+							adjusted_mode,
+							VIA_EXPAND,
+							HOR_SCALE);
+				}
+
+				/* Vertical scaling */
+				if (iga->scaling_mode &
+					VIA_VER_EXPAND) {
+					via_set_iga_scale_function(
+							crtc,
+							VIA_VER_EXPAND);
+					via_load_iga_scale_factor_regs(
+							dev_priv,
+							mode,
+							adjusted_mode,
+							VIA_EXPAND,
+							VER_SCALE);
+				}
+			}
+		}
+
+		/* Relock */
+		via_lock_crtc(VGABASE);
+
+		/* Set non-interlace / interlace mode. */
+		via_iga2_set_interlace_mode(VGABASE,
+					adjusted_mode->flags &
+					DRM_MODE_FLAG_INTERLACE);
+
+		/* Load display FIFO. */
+		ret = via_iga2_display_fifo_regs(dev, dev_priv,
+						iga, adjusted_mode,
+						crtc->primary->fb);
+		if (ret) {
+			goto exit;
+		}
+
+		/* Set PLL */
+		if (adjusted_mode->clock) {
+			u32 clock = adjusted_mode->clock * 1000;
+			u32 pll_regs;
+
+			if (iga->scaling_mode & VIA_SHRINK)
+				clock *= 2;
+			pll_regs = via_get_clk_value(crtc->dev, clock);
+			via_set_vclock(crtc, pll_regs);
+		}
+
+		via_iga_common_init(VGABASE);
+
+		/* Set palette LUT to 8-bit mode. */
+		via_iga2_set_palette_lut_resolution(VGABASE, true);
+
+		svga_wcrt_mask(VGABASE, 0x6A, BIT(7), BIT(7));
+	}
+
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static void via_crtc_helper_atomic_enable(struct drm_crtc *crtc,
+					struct drm_atomic_state *state)
+{
+	struct drm_device *dev = crtc->dev;
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	struct via_crtc *iga = container_of(crtc,
+						struct via_crtc, base);
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if (!iga->index) {
+		svga_wseq_mask(VGABASE, 0x01, 0x00, BIT(5));
+	} else {
+		svga_wcrt_mask(VGABASE, 0x6B, 0x00, BIT(2));
+	}
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static void via_crtc_helper_atomic_disable(struct drm_crtc *crtc,
+					struct drm_atomic_state *state)
+{
+	struct drm_device *dev = crtc->dev;
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	struct via_crtc *iga = container_of(crtc,
+						struct via_crtc, base);
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if (!iga->index) {
+		svga_wseq_mask(VGABASE, 0x01, BIT(5), BIT(5));
+	} else {
+		svga_wcrt_mask(VGABASE, 0x6B, BIT(2), BIT(2));
+	}
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static const struct drm_crtc_helper_funcs via_drm_crtc_helper_funcs = {
+	.mode_set_nofb = via_mode_set_nofb,
+	.atomic_enable = via_crtc_helper_atomic_enable,
+	.atomic_disable = via_crtc_helper_atomic_disable,
+};
+
+static int via_primary_atomic_check(struct drm_plane *plane,
+					struct drm_atomic_state *state)
+{
+	struct drm_plane_state *new_plane_state =
+			drm_atomic_get_new_plane_state(state, plane);
+	struct drm_crtc_state *new_crtc_state;
+	struct drm_device *dev = plane->dev;
+	struct drm_framebuffer *fb = new_plane_state->fb;
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	uint32_t frame_buffer_size;
+	int ret = 0;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if ((!new_plane_state->crtc) || (!new_plane_state->visible)) {
+		goto exit;
+	}
+
+	frame_buffer_size = (fb->width * fb->format->cpp[0]) *
+				fb->height;
+	if (frame_buffer_size > dev_priv->vram_size) {
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	if ((fb->width > dev->mode_config.max_width) ||
+		(fb->width < dev->mode_config.min_width)) {
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	new_crtc_state = drm_atomic_get_new_crtc_state(state,
+						new_plane_state->crtc);
+	ret = drm_atomic_helper_check_plane_state(
+					new_plane_state,
+					new_crtc_state,
+					DRM_PLANE_HELPER_NO_SCALING,
+					DRM_PLANE_HELPER_NO_SCALING,
+					false, true);
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return ret;
+}
+
+static void via_primary_atomic_disable(struct drm_plane *plane,
+					struct drm_atomic_state *state)
+{
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return;
+}
+
+void via_primary_atomic_update(struct drm_plane *plane,
+					struct drm_atomic_state *state)
+{
+	struct drm_plane_state *new_state =
+			drm_atomic_get_new_plane_state(state, plane);
+	struct drm_crtc *crtc = new_state->crtc;
+	struct drm_framebuffer *fb = new_state->fb;
+	uint32_t pitch = (new_state->crtc_y * fb->pitches[0]) +
+			(new_state->crtc_x * fb->format->cpp[0]);
+	uint32_t addr;
+	struct via_crtc *iga = container_of(crtc, struct via_crtc, base);
+	struct drm_device *dev = crtc->dev;
+	struct via_drm_priv *dev_priv = to_via_drm_priv(dev);
+	struct drm_gem_object *gem;
+	struct ttm_buffer_object *ttm_bo;
+	struct via_bo *bo;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	gem = fb->obj[0];
+	ttm_bo = container_of(gem, struct ttm_buffer_object, base);
+	bo = to_ttm_bo(ttm_bo);
+
+	if (!iga->index) {
+		via_iga1_set_color_depth(dev_priv, fb->format->depth);
+
+		/* Set the framebuffer offset */
+		addr = round_up((ttm_bo->resource->start << PAGE_SHIFT) +
+				pitch, 16) >> 1;
+
+		vga_wcrt(VGABASE, 0x0D, addr & 0xFF);
+		vga_wcrt(VGABASE, 0x0C, (addr >> 8) & 0xFF);
+		/* Yes order of setting these registers matters on some hardware */
+		svga_wcrt_mask(VGABASE, 0x48, ((addr >> 24) & 0x1F), 0x1F);
+		vga_wcrt(VGABASE, 0x34, (addr >> 16) & 0xFF);
+
+		/* Load fetch count registers */
+		pitch = ALIGN(crtc->mode.hdisplay * fb->format->cpp[0],
+				16);
+		load_value_to_registers(VGABASE, &iga->fetch, pitch >> 4);
+
+		/* Set the primary pitch */
+		pitch = ALIGN(fb->pitches[0], 16);
+		/* Spec does not say that first adapter skips 3 bits but old
+		 * code did it and seems to be reasonable in analogy to
+		 * second adapter */
+		load_value_to_registers(VGABASE, &iga->offset, pitch >> 3);
+	} else {
+		via_iga2_set_color_depth(dev_priv, fb->format->depth);
+
+		/* Set the framebuffer offset */
+		addr = round_up((ttm_bo->resource->start << PAGE_SHIFT) +
+				pitch, 16);
+		/* Bits 9 to 3 of the frame buffer go into bits 7 to 1
+		 * of the register. Bit 0 is for setting tile mode or
+		 * linear mode. A value of zero sets it to linear mode */
+		vga_wcrt(VGABASE, 0x62, ((addr >> 3) & 0x7F) << 1);
+		vga_wcrt(VGABASE, 0x63, (addr >> 10) & 0xFF);
+		vga_wcrt(VGABASE, 0x64, (addr >> 18) & 0xFF);
+		svga_wcrt_mask(VGABASE, 0xA3, ((addr >> 26) & 0x07), 0x07);
+
+		/* Load fetch count registers */
+		pitch = ALIGN(crtc->mode.hdisplay * (fb->format->cpp[0] * 8) >> 3, 16);
+		load_value_to_registers(VGABASE, &iga->fetch, pitch >> 4);
+
+		/* Set secondary pitch */
+		pitch = ALIGN(fb->pitches[0], 16);
+		load_value_to_registers(VGABASE, &iga->offset, pitch >> 3);
+	}
+
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static int via_primary_prepare_fb(struct drm_plane *plane,
+				struct drm_plane_state *new_state)
+{
+	struct drm_gem_object *gem;
+	struct ttm_buffer_object *ttm_bo;
+	struct via_bo *bo;
+	int ret = 0;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if (!new_state->fb) {
+		goto exit;
+	}
+
+	gem = new_state->fb->obj[0];
+	ttm_bo = container_of(gem, struct ttm_buffer_object, base);
+	bo = to_ttm_bo(ttm_bo);
+
+	ret = ttm_bo_reserve(ttm_bo, true, false, NULL);
+	if (ret) {
+		goto exit;
+	}
+
+	ret = via_bo_pin(bo, TTM_PL_VRAM);
+	ttm_bo_unreserve(ttm_bo);
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return ret;
+}
+
+static void via_primary_cleanup_fb(struct drm_plane *plane,
+				struct drm_plane_state *old_state)
+{
+	struct drm_gem_object *gem;
+	struct ttm_buffer_object *ttm_bo;
+	struct via_bo *bo;
+	int ret;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	if (!old_state->fb) {
+		goto exit;
+	}
+
+	gem = old_state->fb->obj[0];
+	ttm_bo = container_of(gem, struct ttm_buffer_object, base);
+	bo = to_ttm_bo(ttm_bo);
+
+	ret = ttm_bo_reserve(ttm_bo, true, false, NULL);
+	if (ret) {
+		goto exit;
+	}
+
+	via_bo_unpin(bo);
+	ttm_bo_unreserve(ttm_bo);
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+}
+
+static const struct drm_plane_helper_funcs
+via_primary_drm_plane_helper_funcs = {
+	.prepare_fb = via_primary_prepare_fb,
+	.cleanup_fb = via_primary_cleanup_fb,
+	.atomic_check = via_primary_atomic_check,
+	.atomic_update = via_primary_atomic_update,
+	.atomic_disable = via_primary_atomic_disable,
+};
+
+static const struct drm_plane_funcs via_primary_drm_plane_funcs = {
+	.update_plane	= drm_atomic_helper_update_plane,
+	.disable_plane = drm_atomic_helper_disable_plane,
+	.destroy = drm_plane_cleanup,
+	.reset = drm_atomic_helper_plane_reset,
+	.atomic_duplicate_state =
+			drm_atomic_helper_plane_duplicate_state,
+	.atomic_destroy_state =
+			drm_atomic_helper_plane_destroy_state,
+};
+
+static void via_crtc_param_init(struct via_drm_priv *dev_priv,
+					struct drm_crtc *crtc,
+					uint32_t index)
+{
+	struct drm_device *dev = &dev_priv->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	struct via_crtc *iga = container_of(crtc,
+						struct via_crtc, base);
+
+	if (iga->index) {
+		iga->timings.htotal.count = ARRAY_SIZE(iga2_hor_total);
+		iga->timings.htotal.regs = iga2_hor_total;
+
+		iga->timings.hdisplay.count = ARRAY_SIZE(iga2_hor_addr);
+		iga->timings.hdisplay.regs = iga2_hor_addr;
+		if (pdev->device != PCI_DEVICE_ID_VIA_VX900_VGA)
+			iga->timings.hdisplay.count--;
+
+		iga->timings.hblank_start.count = ARRAY_SIZE(iga2_hor_blank_start);
+		iga->timings.hblank_start.regs = iga2_hor_blank_start;
+		if (pdev->device != PCI_DEVICE_ID_VIA_VX900_VGA)
+			iga->timings.hblank_start.count--;
+
+		iga->timings.hblank_end.count = ARRAY_SIZE(iga2_hor_blank_end);
+		iga->timings.hblank_end.regs = iga2_hor_blank_end;
+
+		iga->timings.hsync_start.count = ARRAY_SIZE(iga2_hor_sync_start);
+		iga->timings.hsync_start.regs = iga2_hor_sync_start;
+		if (pdev->device == PCI_DEVICE_ID_VIA_CLE266
+			|| pdev->device == PCI_DEVICE_ID_VIA_KM400)
+			iga->timings.hsync_start.count--;
+
+		iga->timings.hsync_end.count = ARRAY_SIZE(iga2_hor_sync_end);
+		iga->timings.hsync_end.regs = iga2_hor_sync_end;
+
+		iga->timings.vtotal.count = ARRAY_SIZE(iga2_ver_total);
+		iga->timings.vtotal.regs = iga2_ver_total;
+
+		iga->timings.vdisplay.count = ARRAY_SIZE(iga2_ver_addr);
+		iga->timings.vdisplay.regs = iga2_ver_addr;
+
+		iga->timings.vblank_start.count = ARRAY_SIZE(iga2_ver_blank_start);
+		iga->timings.vblank_start.regs = iga2_ver_blank_start;
+
+		iga->timings.vblank_end.count = ARRAY_SIZE(iga2_ver_blank_end);
+		iga->timings.vblank_end.regs = iga2_ver_blank_end;
+
+		iga->timings.vsync_start.count = ARRAY_SIZE(iga2_ver_sync_start);
+		iga->timings.vsync_start.regs = iga2_ver_sync_start;
+
+		iga->timings.vsync_end.count = ARRAY_SIZE(iga2_ver_sync_end);
+		iga->timings.vsync_end.regs = iga2_ver_sync_end;
+
+		/* Secondary FIFO setup */
+		if ((pdev->device == PCI_DEVICE_ID_VIA_CLE266) ||
+			(pdev->device == PCI_DEVICE_ID_VIA_KM400)) {
+			iga->fifo_depth.count =
+				ARRAY_SIZE(iga2_cle266_fifo_depth_select);
+			iga->fifo_depth.regs = iga2_cle266_fifo_depth_select;
+
+			iga->threshold.count =
+				ARRAY_SIZE(iga2_cle266_fifo_threshold_select);
+			iga->threshold.regs = iga2_cle266_fifo_threshold_select;
+		} else {
+			iga->fifo_depth.count = ARRAY_SIZE(iga2_k8m800_fifo_depth_select);
+			iga->fifo_depth.regs = iga2_k8m800_fifo_depth_select;
+
+			iga->threshold.count = ARRAY_SIZE(iga2_k8m800_fifo_threshold_select);
+			iga->threshold.regs = iga2_k8m800_fifo_threshold_select;
+
+			iga->high_threshold.count = ARRAY_SIZE(iga2_fifo_high_threshold_select);
+			iga->high_threshold.regs = iga2_fifo_high_threshold_select;
+
+			iga->display_queue.count = ARRAY_SIZE(iga2_display_queue_expire_num);
+			iga->display_queue.regs = iga2_display_queue_expire_num;
+		}
+
+		iga->fetch.count = ARRAY_SIZE(iga2_fetch_count);
+		iga->fetch.regs = iga2_fetch_count;
+
+		/* Older hardware only uses 12 bits */
+		iga->offset.count = ARRAY_SIZE(iga2_offset) - 1;
+		iga->offset.regs = iga2_offset;
+	} else {
+		iga->timings.htotal.count = ARRAY_SIZE(iga1_hor_total);
+		iga->timings.htotal.regs = iga1_hor_total;
+
+		iga->timings.hdisplay.count = ARRAY_SIZE(iga1_hor_addr);
+		iga->timings.hdisplay.regs = iga1_hor_addr;
+		if (pdev->device != PCI_DEVICE_ID_VIA_VX900_VGA)
+			iga->timings.hdisplay.count--;
+
+		iga->timings.hblank_start.count = ARRAY_SIZE(iga1_hor_blank_start);
+		iga->timings.hblank_start.regs = iga1_hor_blank_start;
+		if (pdev->device != PCI_DEVICE_ID_VIA_VX900_VGA)
+			iga->timings.hblank_start.count--;
+
+		iga->timings.hblank_end.count = ARRAY_SIZE(iga1_hor_blank_end);
+		iga->timings.hblank_end.regs = iga1_hor_blank_end;
+
+		iga->timings.hsync_start.count = ARRAY_SIZE(iga1_hor_sync_start);
+		iga->timings.hsync_start.regs = iga1_hor_sync_start;
+
+		iga->timings.hsync_end.count = ARRAY_SIZE(iga1_hor_sync_end);
+		iga->timings.hsync_end.regs = iga1_hor_sync_end;
+
+		iga->timings.vtotal.count = ARRAY_SIZE(iga1_ver_total);
+		iga->timings.vtotal.regs = iga1_ver_total;
+
+		iga->timings.vdisplay.count = ARRAY_SIZE(iga1_ver_addr);
+		iga->timings.vdisplay.regs = iga1_ver_addr;
+
+		iga->timings.vblank_start.count = ARRAY_SIZE(iga1_ver_blank_start);
+		iga->timings.vblank_start.regs = iga1_ver_blank_start;
+
+		iga->timings.vblank_end.count = ARRAY_SIZE(iga1_ver_blank_end);
+		iga->timings.vblank_end.regs = iga1_ver_blank_end;
+
+		iga->timings.vsync_start.count = ARRAY_SIZE(iga1_ver_sync_start);
+		iga->timings.vsync_start.regs = iga1_ver_sync_start;
+
+		iga->timings.vsync_end.count = ARRAY_SIZE(iga1_ver_sync_end);
+		iga->timings.vsync_end.regs = iga1_ver_sync_end;
+
+		/* Primary FIFO setup */
+		if ((pdev->device == PCI_DEVICE_ID_VIA_CLE266) ||
+			(pdev->device == PCI_DEVICE_ID_VIA_KM400)) {
+			iga->fifo_depth.count = ARRAY_SIZE(iga1_cle266_fifo_depth_select);
+			iga->fifo_depth.regs = iga1_cle266_fifo_depth_select;
+
+			iga->threshold.count = ARRAY_SIZE(iga1_cle266_fifo_threshold_select);
+			iga->threshold.regs = iga1_cle266_fifo_threshold_select;
+
+			iga->high_threshold.count = ARRAY_SIZE(iga1_cle266_fifo_high_threshold_select);
+			iga->high_threshold.regs = iga1_cle266_fifo_high_threshold_select;
+
+			iga->display_queue.count = ARRAY_SIZE(iga1_cle266_display_queue_expire_num);
+			iga->display_queue.regs = iga1_cle266_display_queue_expire_num;
+		} else {
+			iga->fifo_depth.count = ARRAY_SIZE(iga1_k8m800_fifo_depth_select);
+			iga->fifo_depth.regs = iga1_k8m800_fifo_depth_select;
+
+			iga->threshold.count = ARRAY_SIZE(iga1_k8m800_fifo_threshold_select);
+			iga->threshold.regs = iga1_k8m800_fifo_threshold_select;
+
+			iga->high_threshold.count = ARRAY_SIZE(iga1_k8m800_fifo_high_threshold_select);
+			iga->high_threshold.regs = iga1_k8m800_fifo_high_threshold_select;
+
+			iga->display_queue.count = ARRAY_SIZE(iga1_k8m800_display_queue_expire_num);
+			iga->display_queue.regs = iga1_k8m800_display_queue_expire_num;
+		}
+
+		iga->fetch.count = ARRAY_SIZE(iga1_fetch_count);
+		iga->fetch.regs = iga1_fetch_count;
+
+		iga->offset.count = ARRAY_SIZE(iga1_offset);
+		iga->offset.regs = iga1_offset;
+	}
+}
+
+static int via_gamma_init(struct drm_crtc *crtc)
+{
+	u16 *gamma;
+	uint32_t i;
+	int ret;
+
+	DRM_DEBUG_KMS("Entered %s.\n", __func__);
+
+	ret = drm_mode_crtc_set_gamma_size(crtc, 256);
+	if (ret) {
+		DRM_ERROR("Failed to set gamma size!\n");
+		goto exit;
+	}
+
+	gamma = crtc->gamma_store;
+	for (i = 0; i < 256; i++) {
+		gamma[i] = i << 8 | i;
+		gamma[i + 256] = i << 8 | i;
+		gamma[i + 512] = i << 8 | i;
+	}
+
+exit:
+	DRM_DEBUG_KMS("Exiting %s.\n", __func__);
+	return ret;
+}
+
+static const uint32_t via_primary_formats[] = {
+	DRM_FORMAT_XRGB8888,
+	DRM_FORMAT_ARGB8888,
+	DRM_FORMAT_RGB888,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_RGB332,
+};
+
+int via_crtc_init(struct via_drm_priv *dev_priv, uint32_t index)
+{
+	struct drm_device *dev = &dev_priv->dev;
+	struct via_crtc *iga;
+	struct drm_plane *primary;
+	struct drm_plane *cursor;
+	uint32_t possible_crtcs;
+	int ret;
+
+	possible_crtcs = 1 << index;
+
+	primary = kzalloc(sizeof(struct drm_plane), GFP_KERNEL);
+	if (!primary) {
+		ret = -ENOMEM;
+		DRM_ERROR("Failed to allocate a primary plane.\n");
+		goto exit;
+	}
+
+	drm_plane_helper_add(primary,
+			&via_primary_drm_plane_helper_funcs);
+	ret = drm_universal_plane_init(dev, primary, possible_crtcs,
+			&via_primary_drm_plane_funcs,
+			via_primary_formats,
+			ARRAY_SIZE(via_primary_formats),
+			NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
+	if (ret) {
+		DRM_ERROR("Failed to initialize a primary "
+				"plane.\n");
+		goto free_primary;
+	}
+
+	cursor = kzalloc(sizeof(struct drm_plane), GFP_KERNEL);
+	if (!cursor) {
+		ret = -ENOMEM;
+		DRM_ERROR("Failed to allocate a cursor plane.\n");
+		goto cleanup_primary;
+	}
+
+	drm_plane_helper_add(cursor,
+			&via_cursor_drm_plane_helper_funcs);
+	ret = drm_universal_plane_init(dev, cursor, possible_crtcs,
+			&via_cursor_drm_plane_funcs,
+			via_cursor_formats,
+			via_cursor_formats_size,
+			NULL, DRM_PLANE_TYPE_CURSOR, NULL);
+	if (ret) {
+		DRM_ERROR("Failed to initialize a cursor "
+				"plane.\n");
+		goto free_cursor;
+	}
+
+	iga = kzalloc(sizeof(struct via_crtc), GFP_KERNEL);
+	if (!iga) {
+		ret = -ENOMEM;
+		DRM_ERROR("Failed to allocate CRTC storage.\n");
+		goto cleanup_cursor;
+	}
+
+	drm_crtc_helper_add(&iga->base,
+			&via_drm_crtc_helper_funcs);
+	ret = drm_crtc_init_with_planes(dev, &iga->base,
+					primary, cursor,
+					&via_drm_crtc_funcs,
+					NULL);
+	if (ret) {
+		DRM_ERROR("Failed to initialize CRTC!\n");
+		goto free_crtc;
+	}
+
+	iga->index = index;
+
+	via_crtc_param_init(dev_priv, &iga->base, index);
+	ret = via_gamma_init(&iga->base);
+	if (ret) {
+		goto free_crtc;
+	}
+
+	goto exit;
+free_crtc:
+	kfree(iga);
+cleanup_cursor:
+	drm_plane_cleanup(cursor);
+free_cursor:
+	kfree(cursor);
+cleanup_primary:
+	drm_plane_cleanup(primary);
+free_primary:
+	kfree(primary);
+exit:
+	return ret;
+}
