SiS 650/651/740/etc driver by Jake Page <jake@CS.Stanford.EDU>

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@11039 b3059339-0415-0410-9bf9-f77b7e298cf2

1 files changed, 1561 insertions, 0 deletions

diff --git a/vidix/drivers/sis_vid.c b/vidix/drivers/sis_vid.c
new file mode 100644
index 0000000000..088fd80d8a
--- /dev/null
+++ b/vidix/drivers/sis_vid.c
@@ -0,0 +1,1561 @@
+/**
+    VIDIX driver for SiS 300 and 310/325 series chips.
+
+    Copyright 2003 Jake Page, Sugar Media.
+
+    Based on SiS Xv driver:
+    Copyright 2002-2003 by Thomas Winischhofer, Vienna, Austria.
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    2003/10/08 integrated into mplayer/vidix architecture -- Alex Beregszaszi
+**/
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include <unistd.h>
+#include <sys/io.h>
+
+#include "../vidix.h"
+#include "../fourcc.h"
+#include "../../libdha/libdha.h"
+#include "../../libdha/pci_ids.h"
+#include "../../libdha/pci_names.h"
+#include "../../config.h"
+
+#include "sis_regs.h"
+#include "sis_defs.h"
+
+
+/** Random defines **/
+
+#define WATCHDOG_DELAY  500000	/* Watchdog counter for retrace waiting */
+#define IMAGE_MIN_WIDTH         32	/* Min and max source image sizes */
+#define IMAGE_MIN_HEIGHT        24
+#define IMAGE_MAX_WIDTH        720
+#define IMAGE_MAX_HEIGHT       576
+#define IMAGE_MAX_WIDTH_M650  1920
+#define IMAGE_MAX_HEIGHT_M650 1080
+
+#define OVERLAY_MIN_WIDTH       32	/* Minimum overlay sizes */
+#define OVERLAY_MIN_HEIGHT      24
+
+#define DISPMODE_SINGLE1 0x1	/* TW: CRT1 only */
+#define DISPMODE_SINGLE2 0x2	/* TW: CRT2 only */
+#define DISPMODE_MIRROR  0x4	/* TW: CRT1 + CRT2 MIRROR */
+
+#define VMODE_INTERLACED       0x1
+#define VMODE_DOUBLESCAN       0x2
+
+typedef struct {
+    short x1, y1, x2, y2;
+} BoxRec;
+
+typedef struct {
+    int pixelFormat;
+
+    uint16_t pitch;
+    uint16_t origPitch;
+
+    uint8_t keyOP;
+    uint16_t HUSF;
+    uint16_t VUSF;
+    uint8_t IntBit;
+    uint8_t wHPre;
+
+    uint16_t srcW;
+    uint16_t srcH;
+
+    BoxRec dstBox;
+
+    uint32_t PSY;
+    uint32_t PSV;
+    uint32_t PSU;
+    uint8_t bobEnable;
+
+    uint8_t contrastCtrl;
+    uint8_t contrastFactor;
+
+    uint8_t lineBufSize;
+
+     uint8_t(*VBlankActiveFunc) ();
+
+    uint16_t SCREENheight;
+
+} SISOverlayRec, *SISOverlayPtr;
+
+
+/** static variable definitions **/
+static int sis_probed = 0;
+static pciinfo_t pci_info;
+unsigned int sis_verbose = 0;
+
+static void *sis_mem_base;
+/* static void *sis_reg_base; */
+unsigned short sis_iobase;
+
+unsigned int sis_vga_engine = UNKNOWN_VGA;
+static unsigned int sis_displaymode = DISPMODE_SINGLE1;
+static unsigned int sis_has_two_overlays = 0;
+static unsigned int sis_bridge_is_slave = 0;
+static unsigned int sis_shift_value = 1;
+static unsigned int sis_vmode = 0;
+unsigned int sis_vbflags = DISPTYPE_DISP1;
+unsigned int sis_overlay_on_crt1 = 1;
+unsigned int sis_crt1_off = -1;
+unsigned int sis_detected_crt2_devices;
+unsigned int sis_force_crt2_type = CRT2_DEFAULT;
+unsigned int sis_device_id = -1;
+
+static int sis_format;
+static int sis_Yoff = 0;
+static int sis_Voff = 0;
+static int sis_Uoff = 0;
+static int sis_screen_width = 640;
+static int sis_screen_height = 480;
+
+static int sis_frames[VID_PLAY_MAXFRAMES];
+
+static vidix_grkey_t sis_grkey;
+
+static vidix_capability_t sis_cap = {
+    "SiS 300/310/325 Video Driver",
+    "Jake Page",
+    TYPE_OUTPUT,
+    {0, 0, 0, 0},
+    2048,
+    2048,
+    4,
+    4,
+    -1,
+    FLAG_UPSCALER | FLAG_DOWNSCALER | FLAG_EQUALIZER,
+    VENDOR_SIS,
+    -1,
+    {0, 0, 0, 0}
+};
+
+vidix_video_eq_t sis_equal = {
+    VEQ_CAP_BRIGHTNESS | VEQ_CAP_CONTRAST,
+    200, 0, 0, 0, 0, 0, 0, 0
+};
+
+static unsigned short sis_card_ids[] = {
+    DEVICE_SIS_300,
+    DEVICE_SIS_315H,
+    DEVICE_SIS_315,
+    DEVICE_SIS_315PRO,
+    DEVICE_SIS_330,
+    DEVICE_SIS_540_VGA,
+    DEVICE_SIS_550_VGA,
+    DEVICE_SIS_630_VGA,
+    DEVICE_SIS_650_VGA
+};
+
+/** function declarations **/
+
+extern void sis_init_video_bridge();
+
+
+static void set_overlay(SISOverlayPtr pOverlay, int index);
+static void close_overlay();
+static void calc_scale_factor(SISOverlayPtr pOverlay,
+			      int index, int iscrt2);
+static void set_line_buf_size(SISOverlayPtr pOverlay);
+static void merge_line_buf(int enable);
+static void set_format(SISOverlayPtr pOverlay);
+static void set_colorkey();
+
+static void set_brightness(uint8_t brightness);
+static void set_contrast(uint8_t contrast);
+static void set_saturation(char saturation);
+static void set_hue(uint8_t hue);
+#if 0
+static void set_alpha(uint8_t alpha);
+#endif
+
+/* IO Port access functions */
+static uint8_t getvideoreg(uint8_t reg)
+{
+    uint8_t ret;
+    inSISIDXREG(SISVID, reg, ret);
+    return (ret);
+}
+
+static void setvideoreg(uint8_t reg, uint8_t data)
+{
+    outSISIDXREG(SISVID, reg, data);
+}
+
+static void setvideoregmask(uint8_t reg, uint8_t data, uint8_t mask)
+{
+    uint8_t old;
+
+    inSISIDXREG(SISVID, reg, old);
+    data = (data & mask) | (old & (~mask));
+    outSISIDXREG(SISVID, reg, data);
+}
+
+static void setsrregmask(uint8_t reg, uint8_t data, uint8_t mask)
+{
+    uint8_t old;
+
+    inSISIDXREG(SISSR, reg, old);
+    data = (data & mask) | (old & (~mask));
+    outSISIDXREG(SISSR, reg, data);
+}
+
+/* vblank checking*/
+static uint8_t vblank_active_CRT1()
+{
+    /* this may be too simplistic? */
+    return (inSISREG(SISINPSTAT) & 0x08);
+}
+
+static uint8_t vblank_active_CRT2()
+{
+    uint8_t ret;
+    if (sis_vga_engine == SIS_315_VGA) {
+	inSISIDXREG(SISPART1, Index_310_CRT2_FC_VR, ret);
+    } else {
+	inSISIDXREG(SISPART1, Index_CRT2_FC_VR, ret);
+    }
+    return ((ret & 0x02) ^ 0x02);
+}
+
+
+unsigned int vixGetVersion(void)
+{
+    return (VIDIX_VERSION);
+}
+
+static int find_chip(unsigned chip_id)
+{
+    unsigned i;
+    for (i = 0; i < sizeof(sis_card_ids) / sizeof(unsigned short); i++) {
+	if (chip_id == sis_card_ids[i])
+	    return i;
+    }
+    return -1;
+}
+
+int vixProbe(int verbose, int force)
+{
+    pciinfo_t lst[MAX_PCI_DEVICES];
+    unsigned i, num_pci;
+    int err;
+
+    sis_verbose = verbose;
+    force = force;
+    err = pci_scan(lst, &num_pci);
+    if (err) {
+	printf("[SiS] Error occured during pci scan: %s\n", strerror(err));
+	return err;
+    } else {
+	err = ENXIO;
+	for (i = 0; i < num_pci; i++) {
+	    if (lst[i].vendor == VENDOR_SIS) {
+		int idx;
+		const char *dname;
+		idx = find_chip(lst[i].device);
+		if (idx == -1)
+		    continue;
+		dname = pci_device_name(VENDOR_SIS, lst[i].device);
+		dname = dname ? dname : "Unknown chip";
+		if (sis_verbose > 0)
+		    printf("[SiS] Found chip: %s (0x%X)\n",
+			   dname, lst[i].device);
+		sis_device_id = sis_cap.device_id = lst[i].device;
+		err = 0;
+		memcpy(&pci_info, &lst[i], sizeof(pciinfo_t));
+
+		sis_has_two_overlays = 0;
+		switch (sis_cap.device_id) {
+		case DEVICE_SIS_300:
+		case DEVICE_SIS_630_VGA:
+		    sis_has_two_overlays = 1;
+		case DEVICE_SIS_540_VGA:
+		    sis_vga_engine = SIS_300_VGA;
+		    break;
+		case DEVICE_SIS_330:
+		case DEVICE_SIS_550_VGA:
+		    sis_has_two_overlays = 1;
+		case DEVICE_SIS_315H:
+		case DEVICE_SIS_315:
+		case DEVICE_SIS_315PRO:
+		case DEVICE_SIS_650_VGA:
+		    /* M650 & 651 have 2 overlays */
+		    /* JCP: I think this works, but not really tested yet */
+		    {
+			unsigned char CR5F;
+			unsigned char tempreg1, tempreg2;
+
+			inSISIDXREG(SISCR, 0x5F, CR5F);
+			CR5F &= 0xf0;
+			andSISIDXREG(SISCR, 0x5c, 0x07);
+			inSISIDXREG(SISCR, 0x5c, tempreg1);
+			tempreg1 &= 0xf8;
+			setSISIDXREG(SISCR, 0x5c, 0x07, 0xf8);
+			inSISIDXREG(SISCR, 0x5c, tempreg2);
+			tempreg2 &= 0xf8;
+			if ((!tempreg1) || (tempreg2)) {
+			    if (CR5F & 0x80) {
+				sis_has_two_overlays = 1;
+			    }
+			} else {
+			    sis_has_two_overlays = 1;	/* ? */
+			}
+			if (sis_has_two_overlays) {
+			    if (sis_verbose > 0)
+				printf
+				    ("[SiS] detected M650/651 with 2 overlays\n");
+			}
+		    }
+		    sis_vga_engine = SIS_315_VGA;
+		    break;
+		default:
+		    /* should never get here */
+		    sis_vga_engine = UNKNOWN_VGA;
+		    break;
+		}
+	    }
+	}
+    }
+    if (err && sis_verbose) {
+	printf("[SiS] Can't find chip\n");
+    } else {
+	sis_probed = 1;
+    }
+
+    return err;
+}
+
+int vixInit(void)
+{
+    uint8_t sr_data, cr_data, cr_data2;
+    char *env_overlay_crt;
+
+    if (!sis_probed) {
+	printf("[SiS] driver was not probed but is being initialized\n");
+	return (EINTR);
+    }
+
+    /* JCP: this is WRONG.  Need to coordinate w/ sisfb to use correct mem */
+    /* map 16MB scary hack for now. */
+    sis_mem_base = map_phys_mem(pci_info.base0, 0x1000000);
+    /* sis_reg_base = map_phys_mem(pci_info.base1, 0x20000); */
+    sis_iobase = pci_info.base2 & 0xFFFC;
+
+    /* would like to use fb ioctl  - or some other method - here to get
+       current resolution. */
+    inSISIDXREG(SISCR, 0x12, cr_data);
+    inSISIDXREG(SISCR, 0x07, cr_data2);
+    sis_screen_height =
+	((cr_data & 0xff) | ((uint16_t) (cr_data2 & 0x02) << 7) |
+	 ((uint16_t) (cr_data2 & 0x40) << 3) | ((uint16_t) (sr_data & 0x02)
+						<< 9)) + 1;
+
+    inSISIDXREG(SISSR, 0x0b, sr_data);
+    inSISIDXREG(SISCR, 0x01, cr_data);
+    sis_screen_width = (((cr_data & 0xff) |
+			 ((uint16_t) (sr_data & 0x0C) << 6)) + 1) * 8;
+
+    inSISIDXREG(SISSR, Index_SR_Graphic_Mode, sr_data);
+    if (sr_data & 0x20)		/* interlaced mode */
+	sis_vmode |= VMODE_INTERLACED;
+
+#if 0				/* getting back false data here... */
+    /* CR9 bit 7 set = double scan active */
+    inSISIDXREG(SISCR, 0x09, cr_data);
+    if (cr_data & 0x40) {
+	sis_vmode |= VMODE_DOUBLESCAN;
+    }
+#endif
+
+    /* JCP: eventually I'd like to replace this with a call to sisfb
+       SISFB_GET_INFO ioctl to get video bridge info.  Not for now,
+       since it requires a very new and not widely distributed version. */
+    sis_init_video_bridge();
+
+    env_overlay_crt = getenv("VIDIX_CRT");
+    if (env_overlay_crt) {
+	int crt = atoi(env_overlay_crt);
+	if (crt == 1 || crt == 2) {
+	    sis_overlay_on_crt1 = (crt == 1);
+	    if (sis_verbose > 0) {
+		printf
+		    ("[SiS] override: using overlay on CRT%d from VIDIX_CRT\n",
+		     crt);
+	    }
+	}
+    }
+
+    return 0;
+}
+
+void vixDestroy(void)
+{
+    /* unmap_phys_mem(sis_reg_base, 0x20000); */
+    /* JCP: see above, hence also a hack. */
+    unmap_phys_mem(sis_mem_base, 0x1000000);
+}
+
+int vixGetCapability(vidix_capability_t * to)
+{
+    memcpy(to, &sis_cap, sizeof(vidix_capability_t));
+    return 0;
+}
+
+static int is_supported_fourcc(uint32_t fourcc)
+{
+    switch (fourcc) {
+    case IMGFMT_YV12:
+    case IMGFMT_I420:
+    case IMGFMT_UYVY:
+    case IMGFMT_YUY2:
+    case IMGFMT_RGB15:
+    case IMGFMT_RGB16:
+	return 1;
+    default:
+	return 0;
+    }
+}
+
+int vixQueryFourcc(vidix_fourcc_t * to)
+{
+    if (is_supported_fourcc(to->fourcc)) {
+	to->depth = VID_DEPTH_8BPP | VID_DEPTH_16BPP | VID_DEPTH_32BPP;
+	to->flags = VID_CAP_EXPAND | VID_CAP_SHRINK | VID_CAP_COLORKEY;
+	return 0;
+    } else
+	to->depth = to->flags = 0;
+    return ENOSYS;
+}
+
+static int bridge_in_slave_mode()
+{
+    unsigned char usScratchP1_00;
+
+    if (!(sis_vbflags & VB_VIDEOBRIDGE))
+	return 0;
+
+    inSISIDXREG(SISPART1, 0x00, usScratchP1_00);
+    if (((sis_vga_engine == SIS_300_VGA)
+	 && (usScratchP1_00 & 0xa0) == 0x20)
+	|| ((sis_vga_engine == SIS_315_VGA)
+	    && (usScratchP1_00 & 0x50) == 0x10)) {
+	return 1;
+    } else {
+	return 0;
+    }
+}
+
+/* This does not handle X dual head mode, since 1) vidix doesn't support it
+   and 2) it doesn't make sense for other gfx drivers */
+static void set_dispmode()
+{
+    sis_bridge_is_slave = 0;
+
+    if (bridge_in_slave_mode())
+	sis_bridge_is_slave = 1;
+
+    if ((sis_vbflags & VB_DISPMODE_MIRROR) ||
+	(sis_bridge_is_slave && (sis_vbflags & DISPTYPE_DISP2))) {
+	if (sis_has_two_overlays)
+	    sis_displaymode = DISPMODE_MIRROR;	/* TW: CRT1+CRT2 (2 overlays) */
+	else if (!sis_overlay_on_crt1)
+	    sis_displaymode = DISPMODE_SINGLE2;
+	else
+	    sis_displaymode = DISPMODE_SINGLE1;
+    } else {
+	if (sis_vbflags & DISPTYPE_DISP1) {
+	    sis_displaymode = DISPMODE_SINGLE1;	/* TW: CRT1 only */
+	} else {
+	    sis_displaymode = DISPMODE_SINGLE2;	/* TW: CRT2 only */
+	}
+    }
+}
+
+static void set_disptype_regs()
+{
+    switch (sis_displaymode) {
+    case DISPMODE_SINGLE1:	/* TW: CRT1 only */
+	if (sis_verbose > 2) {
+	    printf("[SiS] Setting up overlay on CRT1\n");
+	}
+	if (sis_has_two_overlays) {
+	    setsrregmask(0x06, 0x00, 0xc0);
+	    setsrregmask(0x32, 0x00, 0xc0);
+	} else {
+	    setsrregmask(0x06, 0x00, 0xc0);
+	    setsrregmask(0x32, 0x00, 0xc0);
+	}
+	break;
+    case DISPMODE_SINGLE2:	/* TW: CRT2 only */
+	if (sis_verbose > 2) {
+	    printf("[SiS] Setting up overlay on CRT2\n");
+	}
+	if (sis_has_two_overlays) {
+	    setsrregmask(0x06, 0x80, 0xc0);
+	    setsrregmask(0x32, 0x80, 0xc0);
+	} else {
+	    setsrregmask(0x06, 0x40, 0xc0);
+	    setsrregmask(0x32, 0x40, 0xc0);
+	}
+	break;
+    case DISPMODE_MIRROR:	/* TW: CRT1 + CRT2 */
+    default:
+	if (sis_verbose > 2) {
+	    printf("[SiS] Setting up overlay on CRT1 AND CRT2!\n");
+	}
+	setsrregmask(0x06, 0x80, 0xc0);
+	setsrregmask(0x32, 0x80, 0xc0);
+	break;
+    }
+}
+
+static void init_overlay()
+{
+    /* Initialize first overlay (CRT1) */
+
+    /* Write-enable video registers */
+    setvideoregmask(Index_VI_Control_Misc2, 0x80, 0x81);
+
+    /* Disable overlay */
+    setvideoregmask(Index_VI_Control_Misc0, 0x00, 0x02);
+
+    /* Disable bobEnable */
+    setvideoregmask(Index_VI_Control_Misc1, 0x02, 0x02);
+
+    /* Reset scale control and contrast */
+    setvideoregmask(Index_VI_Scale_Control, 0x60, 0x60);
+    setvideoregmask(Index_VI_Contrast_Enh_Ctrl, 0x04, 0x1F);
+
+    setvideoreg(Index_VI_Disp_Y_Buf_Preset_Low, 0x00);
+    setvideoreg(Index_VI_Disp_Y_Buf_Preset_Middle, 0x00);
+    setvideoreg(Index_VI_UV_Buf_Preset_Low, 0x00);
+    setvideoreg(Index_VI_UV_Buf_Preset_Middle, 0x00);
+    setvideoreg(Index_VI_Disp_Y_UV_Buf_Preset_High, 0x00);
+    setvideoreg(Index_VI_Play_Threshold_Low, 0x00);
+    setvideoreg(Index_VI_Play_Threshold_High, 0x00);
+
+    /* may not want to init these here, could already be set to other
+       values by app? */
+    setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x01);
+    setvideoregmask(Index_VI_Contrast_Enh_Ctrl, 0x04, 0x07);
+    setvideoreg(Index_VI_Brightness, 0x20);
+    if (sis_vga_engine == SIS_315_VGA) {
+	setvideoreg(Index_VI_Hue, 0x00);
+	setvideoreg(Index_VI_Saturation, 0x00);
+    }
+
+    /* Initialize second overlay (CRT2) */
+    if (sis_has_two_overlays) {
+	/* Write-enable video registers */
+	setvideoregmask(Index_VI_Control_Misc2, 0x81, 0x81);
+
+	/* Disable overlay */
+	setvideoregmask(Index_VI_Control_Misc0, 0x00, 0x02);
+
+	/* Disable bobEnable */
+	setvideoregmask(Index_VI_Control_Misc1, 0x02, 0x02);
+
+	/* Reset scale control and contrast */
+	setvideoregmask(Index_VI_Scale_Control, 0x60, 0x60);
+	setvideoregmask(Index_VI_Contrast_Enh_Ctrl, 0x04, 0x1F);
+
+	setvideoreg(Index_VI_Disp_Y_Buf_Preset_Low, 0x00);
+	setvideoreg(Index_VI_Disp_Y_Buf_Preset_Middle, 0x00);
+	setvideoreg(Index_VI_UV_Buf_Preset_Low, 0x00);
+	setvideoreg(Index_VI_UV_Buf_Preset_Middle, 0x00);
+	setvideoreg(Index_VI_Disp_Y_UV_Buf_Preset_High, 0x00);
+	setvideoreg(Index_VI_Play_Threshold_Low, 0x00);
+	setvideoreg(Index_VI_Play_Threshold_High, 0x00);
+
+	setvideoregmask(Index_VI_Control_Misc2, 0x01, 0x01);
+	setvideoregmask(Index_VI_Contrast_Enh_Ctrl, 0x04, 0x07);
+	setvideoreg(Index_VI_Brightness, 0x20);
+	if (sis_vga_engine == SIS_315_VGA) {
+	    setvideoreg(Index_VI_Hue, 0x00);
+	    setvideoreg(Index_VI_Saturation, 0x00);
+	}
+    }
+}
+
+int vixConfigPlayback(vidix_playback_t * info)
+{
+    SISOverlayRec overlay;
+    int srcOffsetX = 0, srcOffsetY = 0;
+    int sx, sy;
+    int index = 0, iscrt2 = 0;
+    int total_size;
+
+    short src_w, drw_w;
+    short src_h, drw_h;
+    short src_x, drw_x;
+    short src_y, drw_y;
+    long dga_offset;
+    int pitch;
+    unsigned int i;
+
+    if (!is_supported_fourcc(info->fourcc))
+	return -1;
+
+    /* set chipset/engine.dependent config info */
+    /*  which CRT to use, etc.? */
+    switch (sis_vga_engine) {
+    case SIS_315_VGA:
+	sis_shift_value = 1;
+	sis_equal.cap |= VEQ_CAP_SATURATION | VEQ_CAP_HUE;
+	break;
+    case SIS_300_VGA:
+    default:
+	sis_shift_value = 2;
+	break;
+    }
+
+    sis_displaymode = DISPMODE_SINGLE1;	/* xV driver code in set_dispmode() */
+    set_dispmode();
+
+    set_disptype_regs();
+
+    init_overlay();
+
+    /* get basic dimension info */
+    src_x = info->src.x;
+    src_y = info->src.y;
+    src_w = info->src.w;
+    src_h = info->src.h;
+
+    drw_x = info->dest.x;
+    drw_y = info->dest.y;
+    drw_w = info->dest.w;
+    drw_h = info->dest.h;
+
+    switch (info->fourcc) {
+    case IMGFMT_YV12:
+    case IMGFMT_I420:
+	pitch = (src_w + 7) & ~7;
+	total_size = (pitch * src_h * 3) >> 1;
+	break;
+    case IMGFMT_YUY2:
+    case IMGFMT_UYVY:
+    case IMGFMT_RGB15:
+    case IMGFMT_RGB16:
+	pitch = ((src_w << 1) + 3) & ~3;
+	total_size = pitch * src_h;
+	break;
+    default:
+	return -1;
+    }
+
+    /* "allocate" memory for overlay! */
+    /* start at 8MB = sisfb's "dri reserved space" -
+       really shouldn't hardcode though */
+    /* XXX: JCP - this can use the sisfb FBIO_ALLOC ioctl to safely
+       allocate "video heap" memory... */
+    dga_offset = 0x800000;
+
+    /* use 7MB for now.  need to calc/get real info from sisfb? */
+    /* this can result in a LOT of frames - probably not necessary */
+    info->num_frames = 0x700000 / (total_size * 2);
+    if (info->num_frames > VID_PLAY_MAXFRAMES)
+	info->num_frames = VID_PLAY_MAXFRAMES;
+
+    info->dga_addr = sis_mem_base + dga_offset;
+    info->dest.pitch.y = 16;
+    info->dest.pitch.u = 16;
+    info->dest.pitch.v = 16;
+    info->offset.y = 0;
+    info->offset.u = 0;
+    info->offset.v = 0;
+    info->frame_size = (total_size * 2);	/* why times 2 ? */
+    for (i = 0; i < info->num_frames; i++) {
+	info->offsets[i] = info->frame_size * i;
+	/* save ptrs to mem buffers */
+	sis_frames[i] = (dga_offset + info->offsets[i]);
+    }
+
+    memset(&overlay, 0, sizeof(overlay));
+    overlay.pixelFormat = sis_format = info->fourcc;
+    overlay.pitch = overlay.origPitch = pitch;
+
+
+    overlay.keyOP = (sis_grkey.ckey.op == CKEY_TRUE ?
+		     VI_ROP_DestKey : VI_ROP_Always);
+
+    overlay.bobEnable = 0x00;
+
+    overlay.SCREENheight = sis_screen_height;
+
+    /* probably will not support X virtual screen > phys very well? */
+    overlay.dstBox.x1 = drw_x;	/* - pScrn->frameX0; */
+    overlay.dstBox.x2 = drw_x + drw_w;	/* - pScrn->frameX0; ??? */
+    overlay.dstBox.y1 = drw_y;	/*  - pScrn->frameY0; */
+    overlay.dstBox.y2 = drw_y + drw_h;	/* - pScrn->frameY0; ??? */
+
+    if ((overlay.dstBox.x1 > overlay.dstBox.x2) ||
+	(overlay.dstBox.y1 > overlay.dstBox.y2))
+	return -1;
+
+    if ((overlay.dstBox.x2 < 0) || (overlay.dstBox.y2 < 0))
+	return -1;
+
+    if (overlay.dstBox.x1 < 0) {
+	srcOffsetX = src_w * (-overlay.dstBox.x1) / drw_w;
+	overlay.dstBox.x1 = 0;
+    }
+    if (overlay.dstBox.y1 < 0) {
+	srcOffsetY = src_h * (-overlay.dstBox.y1) / drw_h;
+	overlay.dstBox.y1 = 0;
+    }
+
+    switch (info->fourcc) {
+    case IMGFMT_YV12:
+	info->dest.pitch.y = 16;
+	sx = (src_x + srcOffsetX) & ~7;
+	sy = (src_y + srcOffsetY) & ~1;
+	info->offset.y = sis_Yoff = sx + sy * pitch;
+	/* JCP: NOTE reversed u & v here!  Not sure why this is needed.
+	   maybe mplayer & sis define U & V differently?? */
+	info->offset.u = sis_Voff =
+	    src_h * pitch + ((sx + sy * pitch / 2) >> 1);
+	info->offset.v = sis_Uoff =
+	    src_h * pitch * 5 / 4 + ((sx + sy * pitch / 2) >> 1);
+
+	overlay.PSY = (sis_frames[0] + sis_Yoff) >> sis_shift_value;
+	overlay.PSV = (sis_frames[0] + sis_Voff) >> sis_shift_value;
+	overlay.PSU = (sis_frames[0] + sis_Uoff) >> sis_shift_value;
+	break;
+    case IMGFMT_I420:
+	sx = (src_x + srcOffsetX) & ~7;
+	sy = (src_y + srcOffsetY) & ~1;
+	info->offset.y = sis_Yoff = sx + sy * pitch;
+	/* JCP: see above... */
+	info->offset.u = sis_Voff =
+	    src_h * pitch * 5 / 4 + ((sx + sy * pitch / 2) >> 1);
+	info->offset.v = sis_Uoff =
+	    src_h * pitch + ((sx + sy * pitch / 2) >> 1);
+
+	overlay.PSY = (sis_frames[0] + sis_Yoff) >> sis_shift_value;
+	overlay.PSV = (sis_frames[0] + sis_Voff) >> sis_shift_value;
+	overlay.PSU = (sis_frames[0] + sis_Uoff) >> sis_shift_value;
+	break;
+    case IMGFMT_YUY2:
+    case IMGFMT_UYVY:
+    case IMGFMT_RGB16:
+    case IMGFMT_RGB15:
+    default:
+	sx = (src_x + srcOffsetX) & ~1;
+	sy = (src_y + srcOffsetY);
+	info->offset.y = sis_Yoff = sx * 2 + sy * pitch;
+
+	overlay.PSY = (sis_frames[0] + sis_Yoff) >> sis_shift_value;
+	break;
+    }
+
+    /* FIXME: is it possible that srcW < 0? */
+    overlay.srcW = src_w - (sx - src_x);
+    overlay.srcH = src_h - (sy - src_y);
+
+    /* JCP: what to do about this? */
+#if 0
+    if ((pPriv->oldx1 != overlay.dstBox.x1) ||
+	(pPriv->oldx2 != overlay.dstBox.x2) ||
+	(pPriv->oldy1 != overlay.dstBox.y1) ||
+	(pPriv->oldy2 != overlay.dstBox.y2)) {
+	pPriv->mustwait = 1;
+	pPriv->oldx1 = overlay.dstBox.x1;
+	pPriv->oldx2 = overlay.dstBox.x2;
+	pPriv->oldy1 = overlay.dstBox.y1;
+	pPriv->oldy2 = overlay.dstBox.y2;
+    }
+#endif
+
+    /* set merge line buffer */
+    merge_line_buf(overlay.srcW > 384);
+
+    /* calculate line buffer length */
+    set_line_buf_size(&overlay);
+
+    if (sis_displaymode == DISPMODE_SINGLE2) {
+	if (sis_has_two_overlays) {
+	    /* TW: On chips with two overlays we use
+	     * overlay 2 for CRT2 */
+	    index = 1;
+	    iscrt2 = 1;
+	} else {
+	    /* TW: On chips with only one overlay we
+	     * use that only overlay for CRT2 */
+	    index = 0;
+	    iscrt2 = 1;
+	}
+	overlay.VBlankActiveFunc = vblank_active_CRT2;
+	/* overlay.GetScanLineFunc = get_scanline_CRT2; */
+    } else {
+	index = 0;
+	iscrt2 = 0;
+	overlay.VBlankActiveFunc = vblank_active_CRT1;
+	/* overlay.GetScanLineFunc = get_scanline_CRT1; */
+    }
+
+    /* calc scale factor (to use below) */
+    calc_scale_factor(&overlay, index, iscrt2);
+
+    /* Select video1 (used for CRT1) or video2 (used for CRT2) */
+    setvideoregmask(Index_VI_Control_Misc2, index, 0x01);
+
+    set_format(&overlay);
+
+    set_colorkey();
+
+    vixPlaybackSetEq(&sis_equal);
+
+    /* set up video overlay registers */
+    set_overlay(&overlay, index);
+
+    /* prevent badness if bits are not at default setting */
+    setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x01);
+    setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x04);
+
+    /* JCP:  Xv driver implementation loops back over above code to
+       setup mirror CRT2 */
+
+    return 0;
+}
+
+int vixPlaybackOn(void)
+{
+    setvideoregmask(Index_VI_Control_Misc0, 0x02, 0x02);
+    return 0;
+}
+
+int vixPlaybackOff(void)
+{
+    unsigned char sridx, cridx;
+    sridx = inSISREG(SISSR);
+    cridx = inSISREG(SISCR);
+    close_overlay();
+    outSISREG(SISSR, sridx);
+    outSISREG(SISCR, cridx);
+
+    return 0;
+}
+
+int vixPlaybackFrameSelect(unsigned int frame)
+{
+    uint8_t data;
+    int index = 0;
+    uint32_t PSY;
+
+    if (sis_displaymode == DISPMODE_SINGLE2 && sis_has_two_overlays) {
+	index = 1;
+    }
+
+    PSY = (sis_frames[frame] + sis_Yoff) >> sis_shift_value;
+
+    /* Unlock address registers */
+    data = getvideoreg(Index_VI_Control_Misc1);
+    setvideoreg(Index_VI_Control_Misc1, data | 0x20);
+    /* TEST: Is this required? */
+    setvideoreg(Index_VI_Control_Misc1, data | 0x20);
+    /* TEST end */
+    /* TEST: Is this required? */
+    if (sis_vga_engine == SIS_315_VGA)
+	setvideoreg(Index_VI_Control_Misc3, 0x00);
+    /* TEST end */
+
+    /* set Y start address */
+    setvideoreg(Index_VI_Disp_Y_Buf_Start_Low, (uint8_t) (PSY));
+    setvideoreg(Index_VI_Disp_Y_Buf_Start_Middle, (uint8_t) ((PSY) >> 8));
+    setvideoreg(Index_VI_Disp_Y_Buf_Start_High, (uint8_t) ((PSY) >> 16));
+    /* set 310/325 series overflow bits for Y plane */
+    if (sis_vga_engine == SIS_315_VGA) {
+	setvideoreg(Index_VI_Y_Buf_Start_Over,
+		    ((uint8_t) ((PSY) >> 24) & 0x01));
+    }
+
+    /* Set U/V data if using plane formats */
+    if ((sis_format == IMGFMT_YV12) || (sis_format == IMGFMT_I420)) {
+
+	uint32_t PSU, PSV;
+
+	PSU = (sis_frames[frame] + sis_Uoff) >> sis_shift_value;
+	PSV = (sis_frames[frame] + sis_Voff) >> sis_shift_value;
+
+	/* set U/V start address */
+	setvideoreg(Index_VI_U_Buf_Start_Low, (uint8_t) PSU);
+	setvideoreg(Index_VI_U_Buf_Start_Middle, (uint8_t) (PSU >> 8));
+	setvideoreg(Index_VI_U_Buf_Start_High, (uint8_t) (PSU >> 16));
+
+	setvideoreg(Index_VI_V_Buf_Start_Low, (uint8_t) PSV);
+	setvideoreg(Index_VI_V_Buf_Start_Middle, (uint8_t) (PSV >> 8));
+	setvideoreg(Index_VI_V_Buf_Start_High, (uint8_t) (PSV >> 16));
+
+	/* 310/325 series overflow bits */
+	if (sis_vga_engine == SIS_315_VGA) {
+	    setvideoreg(Index_VI_U_Buf_Start_Over,
+			((uint8_t) (PSU >> 24) & 0x01));
+	    setvideoreg(Index_VI_V_Buf_Start_Over,
+			((uint8_t) (PSV >> 24) & 0x01));
+	}
+    }
+
+    if (sis_vga_engine == SIS_315_VGA) {
+	/* Trigger register copy for 310 series */
+	setvideoreg(Index_VI_Control_Misc3, 1 << index);
+    }
+
+    /* Lock the address registers */
+    setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x20);
+
+    return 0;
+}
+
+int vixGetGrKeys(vidix_grkey_t * grkey)
+{
+    memcpy(grkey, &sis_grkey, sizeof(vidix_grkey_t));
+    return 0;
+}
+
+int vixSetGrKeys(const vidix_grkey_t * grkey)
+{
+    memcpy(&sis_grkey, grkey, sizeof(vidix_grkey_t));
+    set_colorkey();
+    return 0;
+}
+
+int vixPlaybackGetEq(vidix_video_eq_t * eq)
+{
+    memcpy(eq, &sis_equal, sizeof(vidix_video_eq_t));
+    return 0;
+}
+
+int vixPlaybackSetEq(const vidix_video_eq_t * eq)
+{
+    int br, sat, cr, hue;
+    if (eq->cap & VEQ_CAP_BRIGHTNESS)
+	sis_equal.brightness = eq->brightness;
+    if (eq->cap & VEQ_CAP_CONTRAST)
+	sis_equal.contrast = eq->contrast;
+    if (eq->cap & VEQ_CAP_SATURATION)
+	sis_equal.saturation = eq->saturation;
+    if (eq->cap & VEQ_CAP_HUE)
+	sis_equal.hue = eq->hue;
+    if (eq->cap & VEQ_CAP_RGB_INTENSITY) {
+	sis_equal.red_intensity = eq->red_intensity;
+	sis_equal.green_intensity = eq->green_intensity;
+	sis_equal.blue_intensity = eq->blue_intensity;
+    }
+    sis_equal.flags = eq->flags;
+
+    cr = (sis_equal.contrast + 1000) * 7 / 2000;
+    if (cr < 0)
+	cr = 0;
+    if (cr > 7)
+	cr = 7;
+
+    br = sis_equal.brightness * 127 / 1000;
+    if (br < -128)
+	br = -128;
+    if (br > 127)
+	br = 127;
+
+    sat = (sis_equal.saturation * 7) / 1000;
+    if (sat < -7)
+	sat = -7;
+    if (sat > 7)
+	sat = 7;
+
+    hue = sis_equal.hue * 7 / 1000;
+    if (hue < -8)
+	hue = -8;
+    if (hue > 7)
+	hue = 7;
+
+    set_brightness(br);
+    set_contrast(cr);
+    if (sis_vga_engine == SIS_315_VGA) {
+	set_saturation(sat);
+	set_hue(hue);
+    }
+
+    return 0;
+}
+
+static void set_overlay(SISOverlayPtr pOverlay, int index)
+{
+    uint16_t pitch = 0;
+    uint8_t h_over = 0, v_over = 0;
+    uint16_t top, bottom, left, right;
+    uint16_t screenX = sis_screen_width;
+    uint16_t screenY = sis_screen_height;
+    uint8_t data;
+    uint32_t watchdog;
+
+    top = pOverlay->dstBox.y1;
+    bottom = pOverlay->dstBox.y2;
+    if (bottom > screenY) {
+	bottom = screenY;
+    }
+
+    left = pOverlay->dstBox.x1;
+    right = pOverlay->dstBox.x2;
+    if (right > screenX) {
+	right = screenX;
+    }
+
+    /* JCP: these aren't really tested... */
+    /* TW: DoubleScan modes require Y coordinates * 2 */
+    if (sis_vmode & VMODE_DOUBLESCAN) {
+	top <<= 1;
+	bottom <<= 1;
+    }
+    /* TW: Interlace modes require Y coordinates / 2 */
+    if (sis_vmode & VMODE_INTERLACED) {
+	top >>= 1;
+	bottom >>= 1;
+    }
+
+    h_over = (((left >> 8) & 0x0f) | ((right >> 4) & 0xf0));
+    v_over = (((top >> 8) & 0x0f) | ((bottom >> 4) & 0xf0));
+
+    pitch = pOverlay->pitch >> sis_shift_value;
+
+    /* set line buffer size */
+    setvideoreg(Index_VI_Line_Buffer_Size, pOverlay->lineBufSize);
+
+    /* set color key mode */
+    setvideoregmask(Index_VI_Key_Overlay_OP, pOverlay->keyOP, 0x0F);
+
+    /* TW: We don't have to wait for vertical retrace in all cases */
+    /* JCP: be safe for now. */
+    if (1 /*pPriv->mustwait */ ) {
+	watchdog = WATCHDOG_DELAY;
+	while (pOverlay->VBlankActiveFunc() && --watchdog);
+	watchdog = WATCHDOG_DELAY;
+	while ((!pOverlay->VBlankActiveFunc()) && --watchdog);
+	if (!watchdog && sis_verbose > 0) {
+	    printf("[SiS]: timed out waiting for vertical retrace\n");
+	}
+    }
+
+    /* Unlock address registers */
+    data = getvideoreg(Index_VI_Control_Misc1);
+    setvideoreg(Index_VI_Control_Misc1, data | 0x20);
+    /* TEST: Is this required? */
+    setvideoreg(Index_VI_Control_Misc1, data | 0x20);
+    /* TEST end */
+
+    /* TEST: Is this required? */
+    if (sis_vga_engine == SIS_315_VGA)
+	setvideoreg(Index_VI_Control_Misc3, 0x00);
+    /* TEST end */
+
+    /* Set Y buf pitch */
+    setvideoreg(Index_VI_Disp_Y_Buf_Pitch_Low, (uint8_t) (pitch));
+    setvideoregmask(Index_VI_Disp_Y_UV_Buf_Pitch_Middle,
+		    (uint8_t) (pitch >> 8), 0x0f);
+
+    /* Set Y start address */
+    setvideoreg(Index_VI_Disp_Y_Buf_Start_Low, (uint8_t) (pOverlay->PSY));
+    setvideoreg(Index_VI_Disp_Y_Buf_Start_Middle,
+		(uint8_t) ((pOverlay->PSY) >> 8));
+    setvideoreg(Index_VI_Disp_Y_Buf_Start_High,
+		(uint8_t) ((pOverlay->PSY) >> 16));
+
+    /* set 310/325 series overflow bits for Y plane */
+    if (sis_vga_engine == SIS_315_VGA) {
+	setvideoreg(Index_VI_Disp_Y_Buf_Pitch_High,
+		    (uint8_t) (pitch >> 12));
+	setvideoreg(Index_VI_Y_Buf_Start_Over,
+		    ((uint8_t) ((pOverlay->PSY) >> 24) & 0x01));
+    }
+
+    /* Set U/V data if using plane formats */
+    if ((pOverlay->pixelFormat == IMGFMT_YV12) ||
+	(pOverlay->pixelFormat == IMGFMT_I420)) {
+
+	uint32_t PSU, PSV;
+
+	PSU = pOverlay->PSU;
+	PSV = pOverlay->PSV;
+
+	/* Set U/V pitch */
+	setvideoreg(Index_VI_Disp_UV_Buf_Pitch_Low,
+		    (uint8_t) (pitch >> 1));
+	setvideoregmask(Index_VI_Disp_Y_UV_Buf_Pitch_Middle,
+			(uint8_t) (pitch >> 5), 0xf0);
+
+	/* set U/V start address */
+	setvideoreg(Index_VI_U_Buf_Start_Low, (uint8_t) PSU);
+	setvideoreg(Index_VI_U_Buf_Start_Middle, (uint8_t) (PSU >> 8));
+	setvideoreg(Index_VI_U_Buf_Start_High, (uint8_t) (PSU >> 16));
+
+	setvideoreg(Index_VI_V_Buf_Start_Low, (uint8_t) PSV);
+	setvideoreg(Index_VI_V_Buf_Start_Middle, (uint8_t) (PSV >> 8));
+	setvideoreg(Index_VI_V_Buf_Start_High, (uint8_t) (PSV >> 16));
+
+	/* 310/325 series overflow bits */
+	if (sis_vga_engine == SIS_315_VGA) {
+	    setvideoreg(Index_VI_Disp_UV_Buf_Pitch_High,
+			(uint8_t) (pitch >> 13));
+	    setvideoreg(Index_VI_U_Buf_Start_Over,
+			((uint8_t) (PSU >> 24) & 0x01));
+	    setvideoreg(Index_VI_V_Buf_Start_Over,
+			((uint8_t) (PSV >> 24) & 0x01));
+	}
+    }
+
+    if (sis_vga_engine == SIS_315_VGA) {
+	/* Trigger register copy for 310 series */
+	setvideoreg(Index_VI_Control_Misc3, 1 << index);
+    }
+
+    /* set scale factor */
+    setvideoreg(Index_VI_Hor_Post_Up_Scale_Low,
+		(uint8_t) (pOverlay->HUSF));
+    setvideoreg(Index_VI_Hor_Post_Up_Scale_High,
+		(uint8_t) ((pOverlay->HUSF) >> 8));
+    setvideoreg(Index_VI_Ver_Up_Scale_Low, (uint8_t) (pOverlay->VUSF));
+    setvideoreg(Index_VI_Ver_Up_Scale_High,
+		(uint8_t) ((pOverlay->VUSF) >> 8));
+
+    setvideoregmask(Index_VI_Scale_Control, (pOverlay->IntBit << 3)
+		    | (pOverlay->wHPre), 0x7f);
+
+    /* set destination window position */
+    setvideoreg(Index_VI_Win_Hor_Disp_Start_Low, (uint8_t) left);
+    setvideoreg(Index_VI_Win_Hor_Disp_End_Low, (uint8_t) right);
+    setvideoreg(Index_VI_Win_Hor_Over, (uint8_t) h_over);
+
+    setvideoreg(Index_VI_Win_Ver_Disp_Start_Low, (uint8_t) top);
+    setvideoreg(Index_VI_Win_Ver_Disp_End_Low, (uint8_t) bottom);
+    setvideoreg(Index_VI_Win_Ver_Over, (uint8_t) v_over);
+
+    setvideoregmask(Index_VI_Control_Misc1, pOverlay->bobEnable, 0x1a);
+
+    /* Lock the address registers */
+    setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x20);
+}
+
+
+/* TW: Overlay MUST NOT be switched off while beam is over it */
+static void close_overlay()
+{
+    uint32_t watchdog;
+
+    if ((sis_displaymode == DISPMODE_SINGLE2) ||
+	(sis_displaymode == DISPMODE_MIRROR)) {
+	if (sis_has_two_overlays) {
+	    setvideoregmask(Index_VI_Control_Misc2, 0x01, 0x01);
+	    watchdog = WATCHDOG_DELAY;
+	    while (vblank_active_CRT2() && --watchdog);
+	    watchdog = WATCHDOG_DELAY;
+	    while ((!vblank_active_CRT2()) && --watchdog);
+	    setvideoregmask(Index_VI_Control_Misc0, 0x00, 0x02);
+	    watchdog = WATCHDOG_DELAY;
+	    while (vblank_active_CRT2() && --watchdog);
+	    watchdog = WATCHDOG_DELAY;
+	    while ((!vblank_active_CRT2()) && --watchdog);
+	} else if (sis_displaymode == DISPMODE_SINGLE2) {
+	    setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x01);
+	    watchdog = WATCHDOG_DELAY;
+	    while (vblank_active_CRT1() && --watchdog);
+	    watchdog = WATCHDOG_DELAY;
+	    while ((!vblank_active_CRT1()) && --watchdog);
+	    setvideoregmask(Index_VI_Control_Misc0, 0x00, 0x02);
+	    watchdog = WATCHDOG_DELAY;
+	    while (vblank_active_CRT1() && --watchdog);
+	    watchdog = WATCHDOG_DELAY;
+	    while ((!vblank_active_CRT1()) && --watchdog);
+	}
+    }
+    if ((sis_displaymode == DISPMODE_SINGLE1) ||
+	(sis_displaymode == DISPMODE_MIRROR)) {
+	setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x01);
+	watchdog = WATCHDOG_DELAY;
+	while (vblank_active_CRT1() && --watchdog);
+	watchdog = WATCHDOG_DELAY;
+	while ((!vblank_active_CRT1()) && --watchdog);
+	setvideoregmask(Index_VI_Control_Misc0, 0x00, 0x02);
+	watchdog = WATCHDOG_DELAY;
+	while (vblank_active_CRT1() && --watchdog);
+	watchdog = WATCHDOG_DELAY;
+	while ((!vblank_active_CRT1()) && --watchdog);
+    }
+}
+
+
+static void
+calc_scale_factor(SISOverlayPtr pOverlay, int index, int iscrt2)
+{
+    uint32_t i = 0, mult = 0;
+    int flag = 0;
+
+    int dstW = pOverlay->dstBox.x2 - pOverlay->dstBox.x1;
+    int dstH = pOverlay->dstBox.y2 - pOverlay->dstBox.y1;
+    int srcW = pOverlay->srcW;
+    int srcH = pOverlay->srcH;
+    /*    uint16_t LCDheight = pSiS->LCDheight; */
+    int srcPitch = pOverlay->origPitch;
+    int origdstH = dstH;
+
+    /* get rid of warnings for now */
+    index = index;
+    iscrt2 = iscrt2;
+
+#if 0				/* JCP: don't bother with this for now. */
+    /* TW: Stretch image due to idiotic LCD "auto"-scaling on LVDS (and 630+301B) */
+    if (pSiS->VBFlags & CRT2_LCD) {
+	if (sis_bridge_is_slave) {
+	    if (pSiS->VBFlags & VB_LVDS) {
+		dstH = (dstH * LCDheight) / pOverlay->SCREENheight;
+	    } else if ((sis_vga_engine == SIS_300_VGA) &&
+		       (pSiS->
+			VBFlags & (VB_301B | VB_302B | VB_301LV |
+				   VB_302LV))) {
+		dstH = (dstH * LCDheight) / pOverlay->SCREENheight;
+	    }
+	} else if (iscrt2) {
+	    if (pSiS->VBFlags & VB_LVDS) {
+		dstH = (dstH * LCDheight) / pOverlay->SCREENheight;
+		if (sis_displaymode == DISPMODE_MIRROR)
+		    flag = 1;
+	    } else if ((sis_vga_engine == SIS_300_VGA) &&
+		       (pSiS->
+			VBFlags & (VB_301B | VB_302B | VB_301LV |
+				   VB_302LV))) {
+		dstH = (dstH * LCDheight) / pOverlay->SCREENheight;
+		if (sis_displaymode == DISPMODE_MIRROR)
+		    flag = 1;
+	    }
+	}
+    }
+#endif
+
+    /* TW: For double scan modes, we need to double the height
+     *     (Perhaps we also need to scale LVDS, but I'm not sure.)
+     *     On 310/325 series, we need to double the width as well.
+     *     Interlace mode vice versa.
+     */
+    if (sis_vmode & VMODE_DOUBLESCAN) {
+	dstH = origdstH << 1;
+	flag = 0;
+	if (sis_vga_engine == SIS_315_VGA) {
+	    dstW <<= 1;
+	}
+    }
+    if (sis_vmode & VMODE_INTERLACED) {
+	dstH = origdstH >> 1;
+	flag = 0;
+    }
+
+    if (dstW < OVERLAY_MIN_WIDTH)
+	dstW = OVERLAY_MIN_WIDTH;
+    if (dstW == srcW) {
+	pOverlay->HUSF = 0x00;
+	pOverlay->IntBit = 0x05;
+	pOverlay->wHPre = 0;
+    } else if (dstW > srcW) {
+	dstW += 2;
+	pOverlay->HUSF = (srcW << 16) / dstW;
+	pOverlay->IntBit = 0x04;
+	pOverlay->wHPre = 0;
+    } else {
+	int tmpW = dstW;
+
+	/* TW: It seems, the hardware can't scale below factor .125 (=1/8) if the
+	   pitch isn't a multiple of 256.
+	   TODO: Test this on the 310/325 series!
+	 */
+	if ((srcPitch % 256) || (srcPitch < 256)) {
+	    if (((dstW * 1000) / srcW) < 125)
+		dstW = tmpW = ((srcW * 125) / 1000) + 1;
+	}
+
+	i = 0;
+	pOverlay->IntBit = 0x01;
+	while (srcW >= tmpW) {
+	    tmpW <<= 1;
+	    i++;
+	}
+	pOverlay->wHPre = (uint8_t) (i - 1);
+	dstW <<= (i - 1);
+	if ((srcW % dstW))
+	    pOverlay->HUSF = ((srcW - dstW) << 16) / dstW;
+	else
+	    pOverlay->HUSF = 0x00;
+    }
+
+    if (dstH < OVERLAY_MIN_HEIGHT)
+	dstH = OVERLAY_MIN_HEIGHT;
+    if (dstH == srcH) {
+	pOverlay->VUSF = 0x00;
+	pOverlay->IntBit |= 0x0A;
+    } else if (dstH > srcH) {
+	dstH += 0x02;
+	pOverlay->VUSF = (srcH << 16) / dstH;
+	pOverlay->IntBit |= 0x08;
+    } else {
+	uint32_t realI;
+
+	i = realI = srcH / dstH;
+	pOverlay->IntBit |= 0x02;
+
+	if (i < 2) {
+	    pOverlay->VUSF = ((srcH - dstH) << 16) / dstH;
+	    /* TW: Needed for LCD-scaling modes */
+	    if ((flag) && (mult = (srcH / origdstH)) >= 2)
+		pOverlay->pitch /= mult;
+	} else {
+#if 0
+	    if (((pOverlay->bobEnable & 0x08) == 0x00) &&
+		(((srcPitch * i) >> 2) > 0xFFF)) {
+		pOverlay->bobEnable |= 0x08;
+		srcPitch >>= 1;
+	    }
+#endif
+	    if (((srcPitch * i) >> 2) > 0xFFF) {
+		i = (0xFFF * 2 / srcPitch);
+		pOverlay->VUSF = 0xFFFF;
+	    } else {
+		dstH = i * dstH;
+		if (srcH % dstH)
+		    pOverlay->VUSF = ((srcH - dstH) << 16) / dstH;
+		else
+		    pOverlay->VUSF = 0x00;
+	    }
+	    /* set video frame buffer offset */
+	    pOverlay->pitch = (uint16_t) (srcPitch * i);
+	}
+    }
+}
+
+static void set_line_buf_size(SISOverlayPtr pOverlay)
+{
+    uint8_t preHIDF;
+    uint32_t i;
+    uint32_t line = pOverlay->srcW;
+
+    if ((pOverlay->pixelFormat == IMGFMT_YV12) ||
+	(pOverlay->pixelFormat == IMGFMT_I420)) {
+	preHIDF = pOverlay->wHPre & 0x07;
+	switch (preHIDF) {
+	case 3:
+	    if ((line & 0xffffff00) == line)
+		i = (line >> 8);
+	    else
+		i = (line >> 8) + 1;
+	    pOverlay->lineBufSize = (uint8_t) (i * 32 - 1);
+	    break;
+	case 4:
+	    if ((line & 0xfffffe00) == line)
+		i = (line >> 9);
+	    else
+		i = (line >> 9) + 1;
+	    pOverlay->lineBufSize = (uint8_t) (i * 64 - 1);
+	    break;
+	case 5:
+	    if ((line & 0xfffffc00) == line)
+		i = (line >> 10);
+	    else
+		i = (line >> 10) + 1;
+	    pOverlay->lineBufSize = (uint8_t) (i * 128 - 1);
+	    break;
+	case 6:
+	    if ((line & 0xfffff800) == line)
+		i = (line >> 11);
+	    else
+		i = (line >> 11) + 1;
+	    pOverlay->lineBufSize = (uint8_t) (i * 256 - 1);
+	    break;
+	default:
+	    if ((line & 0xffffff80) == line)
+		i = (line >> 7);
+	    else
+		i = (line >> 7) + 1;
+	    pOverlay->lineBufSize = (uint8_t) (i * 16 - 1);
+	    break;
+	}
+    } else {			/* YUV2, UYVY */
+	if ((line & 0xffffff8) == line)
+	    i = (line >> 3);
+	else
+	    i = (line >> 3) + 1;
+	pOverlay->lineBufSize = (uint8_t) (i - 1);
+    }
+}
+
+static void merge_line_buf(int enable)
+{
+    if (enable) {
+	switch (sis_displaymode) {
+	case DISPMODE_SINGLE1:
+	    if (sis_has_two_overlays) {
+		/* dual line merge */
+		setvideoregmask(Index_VI_Control_Misc2, 0x10, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    } else {
+		setvideoregmask(Index_VI_Control_Misc2, 0x10, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    }
+	    break;
+	case DISPMODE_SINGLE2:
+	    if (sis_has_two_overlays) {
+		/* line merge */
+		setvideoregmask(Index_VI_Control_Misc2, 0x01, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x04, 0x04);
+	    } else {
+		setvideoregmask(Index_VI_Control_Misc2, 0x10, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    }
+	    break;
+	case DISPMODE_MIRROR:
+	default:
+	    /* line merge */
+	    setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x11);
+	    setvideoregmask(Index_VI_Control_Misc1, 0x04, 0x04);
+	    if (sis_has_two_overlays) {
+		/* line merge */
+		setvideoregmask(Index_VI_Control_Misc2, 0x01, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x04, 0x04);
+	    }
+	    break;
+	}
+    } else {
+	switch (sis_displaymode) {
+	case DISPMODE_SINGLE1:
+	    setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x11);
+	    setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    break;
+	case DISPMODE_SINGLE2:
+	    if (sis_has_two_overlays) {
+		setvideoregmask(Index_VI_Control_Misc2, 0x01, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    } else {
+		setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    }
+	    break;
+	case DISPMODE_MIRROR:
+	default:
+	    setvideoregmask(Index_VI_Control_Misc2, 0x00, 0x11);
+	    setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    if (sis_has_two_overlays) {
+		setvideoregmask(Index_VI_Control_Misc2, 0x01, 0x11);
+		setvideoregmask(Index_VI_Control_Misc1, 0x00, 0x04);
+	    }
+	    break;
+	}
+    }
+}
+
+
+static void set_format(SISOverlayPtr pOverlay)
+{
+    uint8_t fmt;
+
+    switch (pOverlay->pixelFormat) {
+    case IMGFMT_YV12:
+    case IMGFMT_I420:
+	fmt = 0x0c;
+	break;
+    case IMGFMT_YUY2:
+	fmt = 0x28;
+	break;
+    case IMGFMT_UYVY:
+	fmt = 0x08;
+	break;
+    case IMGFMT_RGB15:		/* D[5:4] : 00 RGB555, 01 RGB 565 */
+	fmt = 0x00;
+	break;
+    case IMGFMT_RGB16:
+	fmt = 0x10;
+	break;
+    default:
+	fmt = 0x00;
+	break;
+    }
+    setvideoregmask(Index_VI_Control_Misc0, fmt, 0x7c);
+}
+
+static void set_colorkey()
+{
+    uint8_t r, g, b;
+
+    b = (uint8_t) sis_grkey.ckey.blue;
+    g = (uint8_t) sis_grkey.ckey.green;
+    r = (uint8_t) sis_grkey.ckey.red;
+
+    /* set color key mode */
+    setvideoregmask(Index_VI_Key_Overlay_OP,
+		    sis_grkey.ckey.op == CKEY_TRUE ?
+		    VI_ROP_DestKey : VI_ROP_Always, 0x0F);
+
+    /* set colorkey values */
+    setvideoreg(Index_VI_Overlay_ColorKey_Blue_Min, (uint8_t) b);
+    setvideoreg(Index_VI_Overlay_ColorKey_Green_Min, (uint8_t) g);
+    setvideoreg(Index_VI_Overlay_ColorKey_Red_Min, (uint8_t) r);
+
+    setvideoreg(Index_VI_Overlay_ColorKey_Blue_Max, (uint8_t) b);
+    setvideoreg(Index_VI_Overlay_ColorKey_Green_Max, (uint8_t) g);
+    setvideoreg(Index_VI_Overlay_ColorKey_Red_Max, (uint8_t) r);
+}
+
+static void set_brightness(uint8_t brightness)
+{
+    setvideoreg(Index_VI_Brightness, brightness);
+}
+
+static void set_contrast(uint8_t contrast)
+{
+    setvideoregmask(Index_VI_Contrast_Enh_Ctrl, contrast, 0x07);
+}
+
+/* Next 3 functions are 310/325 series only */
+
+static void set_saturation(char saturation)
+{
+    uint8_t temp = 0;
+
+    if (saturation < 0) {
+	temp |= 0x88;
+	saturation = -saturation;
+    }
+    temp |= (saturation & 0x07);
+    temp |= ((saturation & 0x07) << 4);
+
+    setvideoreg(Index_VI_Saturation, temp);
+}
+
+static void set_hue(uint8_t hue)
+{
+    setvideoreg(Index_VI_Hue, (hue & 0x08) ? (hue ^ 0x07) : hue);
+}
+
+#if 0
+/* JCP: not used (I don't think it's correct anyway) */
+static void set_alpha(uint8_t alpha)
+{
+    uint8_t data;
+
+    data = getvideoreg(Index_VI_Key_Overlay_OP);
+    data &= 0x0F;
+    setvideoreg(Index_VI_Key_Overlay_OP, data | (alpha << 4));
+}
+#endif