typedef struct svga_t
{
        mem_mapping_t mapping;
        
        uint8_t crtcreg, crtcreg_mask;
        uint8_t crtc[128];
        uint8_t gdcreg[64];
        int gdcaddr;
        uint8_t attrregs[32];
        int attraddr, attrff;
        int attr_palette_enable;
        uint8_t seqregs[64];
        int seqaddr;
        
        uint8_t miscout;
        int vidclock;

        /*The three variables below allow us to implement memory maps like that seen on a 1MB Trio64 :
          0MB-1MB - VRAM
          1MB-2MB - VRAM mirror
          2MB-4MB - open bus
          4MB-xMB - mirror of above
          
          For the example memory map, decode_mask would be 4MB-1 (4MB address space), vram_max would be 2MB
          (present video memory only responds to first 2MB), vram_mask would be 1MB-1 (video memory wraps at 1MB)
        */
        uint32_t decode_mask;
        uint32_t vram_max;
        uint32_t vram_mask;
        
        uint8_t la, lb, lc, ld;
        
        uint8_t dac_mask, dac_status;
        int dac_read, dac_write, dac_pos;
        int dac_r, dac_g;
                
        uint8_t cgastat;
        
        uint8_t plane_mask;
        
        int fb_only;
        
        int fast;
        uint8_t colourcompare, colournocare;
        int readmode, writemode, readplane;
        int chain4, chain2_write, chain2_read;
        uint8_t writemask;
        uint32_t charseta, charsetb;

        int set_reset_disabled;
        
        uint8_t egapal[16];
        uint32_t pallook[512];
        PALETTE vgapal;
        
        int ramdac_type;

        int vtotal, dispend, vsyncstart, split, vblankstart;
        int hdisp,  hdisp_old, htotal,  hdisp_time, rowoffset;
        int lowres, interlace;
        int linedbl, rowcount;
        double clock;
        uint32_t ma_latch, ca_adj;
        int bpp;
        
        uint64_t dispontime, dispofftime;
        pc_timer_t timer;
        
        uint8_t scrblank;
        
        int dispon;
        int hdisp_on;

        uint32_t ma, maback, ca;
        int vc;
        int sc;
        int linepos, vslines, linecountff, oddeven;
        int con, cursoron, blink;
        int scrollcache_src, scrollcache_dst, scrollcache_dst_reset;
        int char_width;
        
        int firstline, lastline;
        int firstline_draw, lastline_draw;
        int displine;
        
        uint8_t *vram;
        uint8_t *changedvram;
        uint32_t vram_display_mask;
        uint32_t banked_mask;

        uint32_t write_bank, read_bank;
                
        int fullchange;
        
        int video_res_x, video_res_y, video_bpp;
        int video_res_override; /*If clear then SVGA code will set above variables, if
                                  set then card code will*/
        int frames, fps;

        struct
        {
                int ena;
                int x, y;
                int xoff, yoff;
                int xsize, ysize;
                uint32_t addr;
                uint32_t pitch;
                int v_acc, h_acc;
        } hwcursor, hwcursor_latch, overlay, overlay_latch;
        
        int hwcursor_on;
        int overlay_on;
        
        int hwcursor_oddeven;
        int overlay_oddeven;
        
        void (*render)(struct svga_t *svga);
        void (*recalctimings_ex)(struct svga_t *svga);

        void    (*video_out)(uint16_t addr, uint8_t val, void *p);
        uint8_t (*video_in) (uint16_t addr, void *p);

        void (*hwcursor_draw)(struct svga_t *svga, int displine);

        void (*overlay_draw)(struct svga_t *svga, int displine);
        
        void (*vblank_start)(struct svga_t *svga);
        
        void (*adjust_panning)(struct svga_t *svga);

        /*Called when VC=R18 and friends. If this returns zero then MA resetting
          is skipped. Matrox Mystique in Power mode reuses this counter for
          vertical line interrupt*/
        int (*line_compare)(struct svga_t *svga);
        
        /*Called at the start of vertical sync*/
        void (*vsync_callback)(struct svga_t *svga);
        
        /*If set then another device is driving the monitor output and the SVGA
          card should not attempt to display anything */
        int override;
        void *p;

        uint8_t ksc5601_sbyte_mask;
        uint8_t ksc5601_udc_area_msb[2];
        int ksc5601_swap_mode;
        uint16_t ksc5601_english_font_type;

        int vertical_linedbl;
        int horizontal_linedbl;
        
        /*Used to implement CRTC[0x17] bit 2 hsync divisor*/
        int hsync_divisor;

        /*Tseng-style chain4 mode - CRTC dword mode is the same as byte mode, chain4
          addresses are shifted to match*/
        int packed_chain4;

        /*Force CRTC to dword mode, regardless of CR14/CR17. Required for S3 enhanced mode*/
        int force_dword_mode;

        int remap_required;
        uint32_t (*remap_func)(struct svga_t *svga, uint32_t in_addr);
        
        bool swaprb;
} svga_t;

extern int svga_init(svga_t *svga, void *p, int memsize, 
               void (*recalctimings_ex)(struct svga_t *svga),
               uint8_t (*video_in) (uint16_t addr, void *p),
               void    (*video_out)(uint16_t addr, uint8_t val, void *p),
               void (*hwcursor_draw)(struct svga_t *svga, int displine),
               void (*overlay_draw)(struct svga_t *svga, int displine));
void svga_close(svga_t *svga);
extern void svga_recalctimings(svga_t *svga);


uint8_t  svga_read(uint32_t addr, void *p);
uint16_t svga_readw(uint32_t addr, void *p);
uint32_t svga_readl(uint32_t addr, void *p);
void     svga_write(uint32_t addr, uint8_t val, void *p);
void     svga_writew(uint32_t addr, uint16_t val, void *p);
void     svga_writel(uint32_t addr, uint32_t val, void *p);
uint8_t  svga_read_linear(uint32_t addr, void *p);
uint16_t svga_readw_linear(uint32_t addr, void *p);
uint32_t svga_readl_linear(uint32_t addr, void *p);
void     svga_write_linear(uint32_t addr, uint8_t val, void *p);
void     svga_writew_linear(uint32_t addr, uint16_t val, void *p);
void     svga_writel_linear(uint32_t addr, uint32_t val, void *p);

void svga_add_status_info(char *s, int max_len, void *p);

extern uint8_t svga_rotate[8][256];

void svga_out(uint16_t addr, uint8_t val, void *p);
uint8_t svga_in(uint16_t addr, void *p);

svga_t *svga_get_pri();
void svga_set_override(svga_t *svga, int val);

#define RAMDAC_6BIT 0
#define RAMDAC_8BIT 1
void svga_set_ramdac_type(svga_t *svga, int type);

void svga_doblit(int y1, int y2, int wx, int wy, svga_t *svga);
