atafb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

		fix->type=FB_TYPE_PACKED_PIXELS;
		fix->type_aux=0;
		if (mode == TT_SHIFTER_TTHIGH)
			fix->visual=FB_VISUAL_MONO01;
	}
	fix->xpanstep=0;
	fix->ypanstep=1;
	fix->ywrapstep=0;
	fix->line_length = 0;
	fix->accel = FB_ACCEL_ATARIBLITT;
	return 0;
}


static int tt_decode_var( struct fb_var_screeninfo *var,
						  struct atafb_par *par )
{
	int xres=var->xres;
	int yres=var->yres;
	int bpp=var->bits_per_pixel;
	int linelen;
	int yres_virtual = var->yres_virtual;

	if (mono_moni) {
		if (bpp > 1 || xres > sttt_xres*2 || yres >tt_yres*2)
			return -EINVAL;
		par->hw.tt.mode=TT_SHIFTER_TTHIGH;
		xres=sttt_xres*2;
		yres=tt_yres*2;
		bpp=1;
	} else {
		if (bpp > 8 || xres > sttt_xres || yres > tt_yres)
			return -EINVAL;
		if (bpp > 4) {
			if (xres > sttt_xres/2 || yres > tt_yres)
				return -EINVAL;
			par->hw.tt.mode=TT_SHIFTER_TTLOW;
			xres=sttt_xres/2;
			yres=tt_yres;
			bpp=8;
		}
		else if (bpp > 2) {
			if (xres > sttt_xres || yres > tt_yres)
				return -EINVAL;
			if (xres > sttt_xres/2 || yres > st_yres/2) {
				par->hw.tt.mode=TT_SHIFTER_TTMID;
				xres=sttt_xres;
				yres=tt_yres;
				bpp=4;
			}
			else {
				par->hw.tt.mode=TT_SHIFTER_STLOW;
				xres=sttt_xres/2;
				yres=st_yres/2;
				bpp=4;
			}
		}
		else if (bpp > 1) {
			if (xres > sttt_xres || yres > st_yres/2)
				return -EINVAL;
			par->hw.tt.mode=TT_SHIFTER_STMID;
			xres=sttt_xres;
			yres=st_yres/2;
			bpp=2;
		}
		else if (var->xres > sttt_xres || var->yres > st_yres) {
			return -EINVAL;
		}
		else {
			par->hw.tt.mode=TT_SHIFTER_STHIGH;
			xres=sttt_xres;
			yres=st_yres;
			bpp=1;
		}
	}
	if (yres_virtual <= 0)
		yres_virtual = 0;
	else if (yres_virtual < yres)
		yres_virtual = yres;
	if (var->sync & FB_SYNC_EXT)
		par->hw.tt.sync=0;
	else
		par->hw.tt.sync=1;
	linelen=xres*bpp/8;
	if (yres_virtual * linelen > screen_len && screen_len)
		return -EINVAL;
	if (yres * linelen > screen_len && screen_len)
		return -EINVAL;
	if (var->yoffset + yres > yres_virtual && yres_virtual)
		return -EINVAL;
	par->yres_virtual = yres_virtual;
	par->screen_base = screen_base + var->yoffset * linelen;
	return 0;
}

static int tt_encode_var( struct fb_var_screeninfo *var,
						  struct atafb_par *par )
{
	int linelen;
	memset(var, 0, sizeof(struct fb_var_screeninfo));
	var->red.offset=0;
	var->red.length=4;
	var->red.msb_right=0;
	var->grayscale=0;

	var->pixclock=31041;
	var->left_margin=120;		/* these may be incorrect 	*/
	var->right_margin=100;
	var->upper_margin=8;
	var->lower_margin=16;
	var->hsync_len=140;
	var->vsync_len=30;

	var->height=-1;
	var->width=-1;

	if (par->hw.tt.sync & 1)
		var->sync=0;
	else
		var->sync=FB_SYNC_EXT;

	switch (par->hw.tt.mode & TT_SHIFTER_MODEMASK) {
	case TT_SHIFTER_STLOW:
		var->xres=sttt_xres/2;
		var->xres_virtual=sttt_xres_virtual/2;
		var->yres=st_yres/2;
		var->bits_per_pixel=4;
		break;
	case TT_SHIFTER_STMID:
		var->xres=sttt_xres;
		var->xres_virtual=sttt_xres_virtual;
		var->yres=st_yres/2;
		var->bits_per_pixel=2;
		break;
	case TT_SHIFTER_STHIGH:
		var->xres=sttt_xres;
		var->xres_virtual=sttt_xres_virtual;
		var->yres=st_yres;
		var->bits_per_pixel=1;
		break;
	case TT_SHIFTER_TTLOW:
		var->xres=sttt_xres/2;
		var->xres_virtual=sttt_xres_virtual/2;
		var->yres=tt_yres;
		var->bits_per_pixel=8;
		break;
	case TT_SHIFTER_TTMID:
		var->xres=sttt_xres;
		var->xres_virtual=sttt_xres_virtual;
		var->yres=tt_yres;
		var->bits_per_pixel=4;
		break;
	case TT_SHIFTER_TTHIGH:
		var->red.length=0;
		var->xres=sttt_xres*2;
		var->xres_virtual=sttt_xres_virtual*2;
		var->yres=tt_yres*2;
		var->bits_per_pixel=1;
		break;
	}		
	var->blue=var->green=var->red;
	var->transp.offset=0;
	var->transp.length=0;
	var->transp.msb_right=0;
	linelen=var->xres_virtual * var->bits_per_pixel / 8;
	if (! use_hwscroll)
		var->yres_virtual=var->yres;
	else if (screen_len) {
		if (par->yres_virtual)
			var->yres_virtual = par->yres_virtual;
		else
			/* yres_virtual==0 means use maximum */
			var->yres_virtual = screen_len / linelen;
	} else {
		if (hwscroll < 0)
			var->yres_virtual = 2 * var->yres;
		else
			var->yres_virtual=var->yres+hwscroll * 16;
	}
	var->xoffset=0;
	if (screen_base)
		var->yoffset=(par->screen_base - screen_base)/linelen;
	else
		var->yoffset=0;
	var->nonstd=0;
	var->activate=0;
	var->vmode=FB_VMODE_NONINTERLACED;
	return 0;
}


static void tt_get_par( struct atafb_par *par )
{
	unsigned long addr;
	par->hw.tt.mode=shifter_tt.tt_shiftmode;
	par->hw.tt.sync=shifter.syncmode;
	addr = ((shifter.bas_hi & 0xff) << 16) |
	       ((shifter.bas_md & 0xff) << 8)  |
	       ((shifter.bas_lo & 0xff));
	par->screen_base = phys_to_virt(addr);
}

static void tt_set_par( struct atafb_par *par )
{
	shifter_tt.tt_shiftmode=par->hw.tt.mode;
	shifter.syncmode=par->hw.tt.sync;
	/* only set screen_base if really necessary */
	if (current_par.screen_base != par->screen_base)
		fbhw->set_screen_base(par->screen_base);
}


static int tt_getcolreg(unsigned regno, unsigned *red,
			unsigned *green, unsigned *blue,
			unsigned *transp, struct fb_info *info)
{
	int t, col;

	if ((shifter_tt.tt_shiftmode & TT_SHIFTER_MODEMASK) == TT_SHIFTER_STHIGH)
		regno += 254;
	if (regno > 255)
		return 1;
	t = tt_palette[regno];
	col = t & 15;
	col |= col << 4;
	col |= col << 8;
	*blue = col;
	col = (t >> 4) & 15;
	col |= col << 4;
	col |= col << 8;
	*green = col;
	col = (t >> 8) & 15;
	col |= col << 4;
	col |= col << 8;
	*red = col;
	*transp = 0;
	return 0;
}


static int tt_setcolreg(unsigned regno, unsigned red,
			unsigned green, unsigned blue,
			unsigned transp, struct fb_info *info)
{
	if ((shifter_tt.tt_shiftmode & TT_SHIFTER_MODEMASK) == TT_SHIFTER_STHIGH)
		regno += 254;
	if (regno > 255)
		return 1;
	tt_palette[regno] = (((red >> 12) << 8) | ((green >> 12) << 4) |
			     (blue >> 12));
	if ((shifter_tt.tt_shiftmode & TT_SHIFTER_MODEMASK) ==
		TT_SHIFTER_STHIGH && regno == 254)
		tt_palette[0] = 0;
	return 0;
}

						  
static int tt_detect( void )

{	struct atafb_par par;

	/* Determine the connected monitor: The DMA sound must be
	 * disabled before reading the MFP GPIP, because the Sound
	 * Done Signal and the Monochrome Detect are XORed together!
	 *
	 * Even on a TT, we should look if there is a DMA sound. It was
	 * announced that the Eagle is TT compatible, but only the PCM is
	 * missing...
	 */
	if (ATARIHW_PRESENT(PCM_8BIT)) { 
		tt_dmasnd.ctrl = DMASND_CTRL_OFF;
		udelay(20);	/* wait a while for things to settle down */
	}
	mono_moni = (mfp.par_dt_reg & 0x80) == 0;

	tt_get_par(&par);
	tt_encode_var(&atafb_predefined[0], &par);

	return 1;
}

#endif /* ATAFB_TT */

/* ------------------- Falcon specific functions ---------------------- */

#ifdef ATAFB_FALCON

static int mon_type;		/* Falcon connected monitor */
static int f030_bus_width;	/* Falcon ram bus width (for vid_control) */
#define F_MON_SM	0
#define F_MON_SC	1
#define F_MON_VGA	2
#define F_MON_TV	3

static struct pixel_clock {
	unsigned long f;	/* f/[Hz] */
	unsigned long t;	/* t/[ps] (=1/f) */
	int right, hsync, left;	/* standard timing in clock cycles, not pixel */
		/* hsync initialized in falcon_detect() */
	int sync_mask;		/* or-mask for hw.falcon.sync to set this clock */
	int control_mask;	/* ditto, for hw.falcon.vid_control */
}
f25  = {25175000, 39721, 18, 0, 42, 0x0, VCO_CLOCK25},
f32  = {32000000, 31250, 18, 0, 42, 0x0, 0},
fext = {       0,     0, 18, 0, 42, 0x1, 0};

/* VIDEL-prescale values [mon_type][pixel_length from VCO] */
static int vdl_prescale[4][3] = {{4,2,1}, {4,2,1}, {4,2,2}, {4,2,1}};

/* Default hsync timing [mon_type] in picoseconds */
static long h_syncs[4] = {3000000, 4875000, 4000000, 4875000};

#ifdef FBCON_HAS_CFB16
static u16 fbcon_cfb16_cmap[16];
#endif

static inline int hxx_prescale(struct falcon_hw *hw)
{
	return hw->ste_mode ? 16 :
		   vdl_prescale[mon_type][hw->vid_mode >> 2 & 0x3];
}

static int falcon_encode_fix( struct fb_fix_screeninfo *fix,
							  struct atafb_par *par )
{
	strcpy(fix->id, "Atari Builtin");
	fix->smem_start = (unsigned long)real_screen_base;
	fix->smem_len = screen_len;
	fix->type = FB_TYPE_INTERLEAVED_PLANES;
	fix->type_aux = 2;
	fix->visual = FB_VISUAL_PSEUDOCOLOR;
	fix->xpanstep = 1;
	fix->ypanstep = 1;
	fix->ywrapstep = 0;
	if (par->hw.falcon.mono) {
		fix->type = FB_TYPE_PACKED_PIXELS;
		fix->type_aux = 0;
		/* no smooth scrolling with longword aligned video mem */
		fix->xpanstep = 32;
	}
	else if (par->hw.falcon.f_shift & 0x100) {
		fix->type = FB_TYPE_PACKED_PIXELS;
		fix->type_aux = 0;
		/* Is this ok or should it be DIRECTCOLOR? */
		fix->visual = FB_VISUAL_TRUECOLOR;
		fix->xpanstep = 2;
	}
	fix->line_length = 0;
	fix->accel = FB_ACCEL_ATARIBLITT;
	return 0;
}


static int falcon_decode_var( struct fb_var_screeninfo *var,
							  struct atafb_par *par )
{
	int bpp = var->bits_per_pixel;
	int xres = var->xres;
	int yres = var->yres;
	int xres_virtual = var->xres_virtual;
	int yres_virtual = var->yres_virtual;
	int left_margin, right_margin, hsync_len;
	int upper_margin, lower_margin, vsync_len;
	int linelen;
	int interlace = 0, doubleline = 0;
	struct pixel_clock *pclock;
	int plen; /* width of pixel in clock cycles */
	int xstretch;
	int prescale;
	int longoffset = 0;
	int hfreq, vfreq;

/*
	Get the video params out of 'var'. If a value doesn't fit, round
	it up, if it's too big, return EINVAL.
	Round up in the following order: bits_per_pixel, xres, yres, 
	xres_virtual, yres_virtual, xoffset, yoffset, grayscale, bitfields, 
	horizontal timing, vertical timing.

	There is a maximum of screen resolution determined by pixelclock
	and minimum frame rate -- (X+hmarg.)*(Y+vmarg.)*vfmin <= pixelclock.
	In interlace mode this is     "     *    "     *vfmin <= pixelclock.
	Additional constraints: hfreq.
	Frequency range for multisync monitors is given via command line.
	For TV and SM124 both frequencies are fixed.

	X % 16 == 0 to fit 8x?? font (except 1 bitplane modes must use X%32==0)
	Y % 16 == 0 to fit 8x16 font
	Y % 8 == 0 if Y<400

	Currently interlace and doubleline mode in var are ignored. 
	On SM124 and TV only the standard resolutions can be used.
*/

	/* Reject uninitialized mode */
	if (!xres || !yres || !bpp)
		return -EINVAL;

	if (mon_type == F_MON_SM && bpp != 1) {
		return -EINVAL;
	}
	else if (bpp <= 1) {
		bpp = 1;
		par->hw.falcon.f_shift = 0x400;
		par->hw.falcon.st_shift = 0x200;
	}
	else if (bpp <= 2) {
		bpp = 2;
		par->hw.falcon.f_shift = 0x000;
		par->hw.falcon.st_shift = 0x100;
	}
	else if (bpp <= 4) {
		bpp = 4;
		par->hw.falcon.f_shift = 0x000;
		par->hw.falcon.st_shift = 0x000;
	}
	else if (bpp <= 8) {
		bpp = 8;
		par->hw.falcon.f_shift = 0x010;
	}
	else if (bpp <= 16) {
		bpp = 16; /* packed pixel mode */
		par->hw.falcon.f_shift = 0x100; /* hicolor, no overlay */
	}
	else
		return -EINVAL;
	par->hw.falcon.bpp = bpp;

	if (mon_type == F_MON_SM || DontCalcRes) {
		/* Skip all calculations. VGA/TV/SC1224 only supported. */
		struct fb_var_screeninfo *myvar = &atafb_predefined[0];
		
		if (bpp > myvar->bits_per_pixel ||
			var->xres > myvar->xres ||
			var->yres > myvar->yres)
			return -EINVAL;
		fbhw->get_par(par);	/* Current par will be new par */
		goto set_screen_base;	/* Don't forget this */
	}

	/* Only some fixed resolutions < 640x400 */
	if (xres <= 320)
		xres = 320;
	else if (xres <= 640 && bpp != 16)
		xres = 640;
	if (yres <= 200)
		yres = 200;
	else if (yres <= 240)
		yres = 240;
	else if (yres <= 400)
		yres = 400;

	/* 2 planes must use STE compatibility mode */
	par->hw.falcon.ste_mode = bpp==2;
	par->hw.falcon.mono = bpp==1;

	/* Total and visible scanline length must be a multiple of one longword,
	 * this and the console fontwidth yields the alignment for xres and
	 * xres_virtual.
	 * TODO: this way "odd" fontheights are not supported
	 *
	 * Special case in STE mode: blank and graphic positions don't align,
	 * avoid trash at right margin
	 */
	if (par->hw.falcon.ste_mode)
		xres = (xres + 63) & ~63;
	else if (bpp == 1)
		xres = (xres + 31) & ~31;
	else
		xres = (xres + 15) & ~15;
	if (yres >= 400)
		yres = (yres + 15) & ~15;