tridentfb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

	bmove:		trident_bmove,
	clear:		trident_16bpp_clear,
	putc:		fbcon_cfb16_putc,
	putcs:		fbcon_cfb16_putcs,
	revc:		fbcon_cfb16_revc,
	clear_margins:	fbcon_cfb16_clear_margins,
	fontwidthmask:	FONTWIDTH (4) | FONTWIDTH (8) | FONTWIDTH (12) | FONTWIDTH (16)
};
#endif
#ifdef FBCON_HAS_CFB32
static void trident_32bpp_clear (struct vc_data *conp, struct display *p,
				int sy, int sx, int height, int width)
{
	int c;
	c = ((u32*)p->dispsw_data)[attr_bgcol_ec(p,conp)];
	trident_clear_helper(c,p,sy,sx,height,width);
}

static struct display_switch trident_32bpp = {
	setup:		fbcon_cfb32_setup,
	bmove:		trident_bmove,
	clear:		trident_32bpp_clear,
	putc:		fbcon_cfb32_putc,
	putcs:		fbcon_cfb32_putcs,
	revc:		fbcon_cfb32_revc,
	clear_margins:	fbcon_cfb32_clear_margins,
	fontwidthmask:	FONTWIDTH (4) | FONTWIDTH (8) | FONTWIDTH (12) | FONTWIDTH (16)
};
#endif

/*
 * Hardware access functions
 */

static inline unsigned char read3X4(int reg)
{
	writeb(reg, fb_info.io_virt + CRT + 4);
	return readb(fb_info.io_virt + CRT + 5);
}

static inline void write3X4(int reg, unsigned char val)
{
	writeb(reg, fb_info.io_virt + CRT + 4);
	writeb(val, fb_info.io_virt + CRT + 5);
}

static inline unsigned char read3C4(int reg)
{
	t_outb(reg, 0x3C4);
	return t_inb(0x3C5);
}

static inline void write3C4(int reg, unsigned char val)
{
	t_outb(reg, 0x3C4);
	t_outb(val, 0x3C5);
}

static inline unsigned char read3CE(int reg)
{
	t_outb(reg, 0x3CE);
	return t_inb(0x3CF);
}

static inline void writeAttr(int reg, unsigned char val)
{
	readb(fb_info.io_virt + CRT + 0x0A);	//flip-flop to index
	t_outb(reg, 0x3C0);
	t_outb(val, 0x3C0);
}

static inline unsigned char readAttr(int reg)
{
	readb(fb_info.io_virt + CRT + 0x0A);	//flip-flop to index
	t_outb(reg, 0x3C0);
	return t_inb(0x3C1);
}

static inline void write3CE(int reg, unsigned char val)
{
	t_outb(reg, 0x3CE);
	t_outb(val, 0x3CF);
}

#define bios_reg(reg) 	write3CE(BiosReg, reg)
#if 0
static inline void unprotect_all(void)
{
	outb(Protection, 0x3C4);
	outb(0x92, 0x3C5);
}
#endif
static inline void enable_mmio(void)
{
	/* Goto New Mode */
	outb(0x0B, 0x3C4);
	inb(0x3C5);

	/* Unprotect registers */
	outb(NewMode1, 0x3C4);
	outb(0x80, 0x3C5);
  
	/* Enable MMIO */
	outb(PCIReg, 0x3D4); 
	outb(inb(0x3D5) | 0x01, 0x3D5);
}


#define crtc_unlock()	write3X4(CRTVSyncEnd, read3X4(CRTVSyncEnd) & 0x7F)

/*  Return flat panel's maximum x resolution */
static int __init get_nativex(void)
{
	int x,y,tmp;

	if (nativex)
		return nativex;

       	tmp = (read3CE(VertStretch) >> 4) & 3;

	switch (tmp) {
		case 0: x = 1280; y = 1024; break;
		case 2: x = 1024; y = 768;  break;
		case 3: x = 800;  y = 600;  break; 
		case 4: x = 1400; y = 1050; break;
		case 1: 
		default:x = 640;  y = 480;  break;
	}

	output("%dx%d flat panel found\n", x, y);
	return x;
}

/* Set pitch */
static void set_lwidth(int width)
{
	write3X4(Offset, width & 0xFF);
	write3X4(AddColReg, (read3X4(AddColReg) & 0xCF) | ((width & 0x300) >>4));
}

/* For resolutions smaller than FP resolution stretch */
static void screen_stretch(void)
{
	write3CE(VertStretch,(read3CE(VertStretch) & 0x7C) | 1);
	write3CE(HorStretch,(read3CE(HorStretch) & 0x7C) | 1);
}

/* For resolutions smaller than FP resolution center */
static void screen_center(void)
{
	bios_reg(0);		// no stretch
	write3CE(VertStretch,(read3CE(VertStretch) & 0x7C) | 0x80);
	write3CE(HorStretch,(read3CE(HorStretch) & 0x7C) | 0x80);
}

/* Address of first shown pixel in display memory */
static void set_screen_start(int base)
{
	write3X4(StartAddrLow, base & 0xFF);
	write3X4(StartAddrHigh, (base & 0xFF00) >> 8);
	write3X4(CRTCModuleTest, (read3X4(CRTCModuleTest) & 0xDF) | ((base & 0x10000) >> 11));
	write3X4(CRTHiOrd, (read3X4(CRTHiOrd) & 0xF8) | ((base & 0xE0000) >> 17));
}

/* Use 20.12 fixed-point for NTSC value and frequency calculation */
#define calc_freq(n,m,k)  ( ((unsigned long)0xE517 * (n+8) / ((m+2)*(1<<k))) >> 12 )

/* Set dotclock frequency */
static void set_vclk(int freq)
{
	int m,n,k;
	int f,fi,d,di;
	unsigned char lo=0,hi=0;

	d = 20;
	for(k = 2;k>=0;k--)
	for(m = 0;m<63;m++)
	for(n = 0;n<128;n++) {
		fi = calc_freq(n,m,k);
		if ((di = abs(fi - freq)) < d) {
			d = di;
			f = fi;
			lo = n;
			hi = (k<<6) | m;
		}
	}
	if (chip3D) {
		write3C4(ClockHigh,hi);
		write3C4(ClockLow,lo);
	} else {
		outb(lo,0x43C8);
		outb(hi,0x43C9);
	}
	debug("VCLK = %X %X\n",hi,lo);
}

/* Set number of lines for flat panels*/
static void set_number_of_lines(int lines)
{
	int tmp = read3CE(CyberEnhance) & 0x8F;
	if (lines > 768)
		tmp |= 0x30;
	else if (lines > 600)
		tmp |= 0x20;
	else if (lines > 480)
		tmp |= 0x10;
	write3CE(CyberEnhance, tmp);
}

/*
 * If we see that FP is active we assume we have one.
 * Otherwise we have a CRT display.User can override.
 */
static unsigned int __init get_displaytype(void)
{
	if (fp)
		return DISPLAY_FP;
	if (crt)
		return DISPLAY_CRT;
	return (read3CE(FPConfig) & 0x10)?DISPLAY_FP:DISPLAY_CRT;
}

/* Try detecting the video memory size */
static unsigned int __init get_memsize(void)
{
	unsigned char tmp, tmp2;
	unsigned int k;

	/* If memory size provided by user */
	if (memsize)
		k = memsize * Kb;
	else
	switch (chip_id) {
		case CYBER9525DVD:    k = 2560 * Kb; break;
		default:
			tmp = read3X4(SPR) & 0x0F;
			switch (tmp) {

				case 0x01: k = 512;     break;
				case 0x02: k = 6 * Mb;  break; /* XP */
				case 0x03: k = 1 * Mb;  break;
				case 0x04: k = 8 * Mb;  break;
				case 0x06: k = 10 * Mb; break; /* XP */
				case 0x07: k = 2 * Mb;  break;
				case 0x08: k = 12 * Mb; break; /* XP */
				case 0x0A: k = 14 * Mb; break; /* XP */
				case 0x0C: k = 16 * Mb; break; /* XP */
				case 0x0E:                     /* XP */
  
					tmp2 = read3C4(0xC1);
					switch (tmp2) {
						case 0x00: k = 20 * Mb; break;
						case 0x01: k = 24 * Mb; break;
						case 0x10: k = 28 * Mb; break;
						case 0x11: k = 32 * Mb; break;
						default:   k = 1 * Mb;  break;
					}
				break;
	
				case 0x0F: k = 4 * Mb; break;
				default:   k = 1 * Mb;
			}
	}

	k -= memdiff * Kb;
	output("framebuffer size = %d Kb\n", k/Kb);
	return k;
}

/* Fill in fix */
static int trident_encode_fix(struct fb_fix_screeninfo *fix,
				  const void *par,
				  struct fb_info_gen *info)
{
	struct tridentfb_info * i = (struct tridentfb_info *)info;
	struct tridentfb_par * p = (struct tridentfb_par *)par;

	debug("enter\n");

	memset(fix, 0, sizeof(struct fb_fix_screeninfo));
	strcpy(fix->id,tridentfb_name);

	fix->smem_start = i->fbmem;
	fix->smem_len = i->memsize;

	fix->type = FB_TYPE_PACKED_PIXELS;
	fix->type_aux = 0;

	fix->visual = p->bpp==8 ? FB_VISUAL_PSEUDOCOLOR:FB_VISUAL_TRUECOLOR;

	fix->xpanstep = fix->ywrapstep = 0;
	fix->ypanstep = 1;
	fix->line_length = p->linelength;
	fix->mmio_start = 0;
	fix->mmio_len = 0;

	fix->accel = FB_ACCEL_NONE;

	debug("exit\n");
	return 0;
}

/* Fill in par from var */
static int trident_decode_var(const struct fb_var_screeninfo *var,
				  void *par,
				  struct fb_info_gen *info)
{
	struct tridentfb_par * p = (struct tridentfb_par *)par;
	struct tridentfb_info * i = (struct tridentfb_info *)info;
	int vres,vfront,vback,vsync;
	debug("enter\n");
	p->var = *var;
	p->bpp = var->bits_per_pixel;

	if (p->bpp == 24 )
		p->bpp = 32;

	p->linelength = var->xres_virtual * p->bpp/8;

	switch (p->bpp) {
		case 8:
			p->var.red.offset = 0;
			p->var.green.offset = 0;
			p->var.blue.offset = 0;
			p->var.red.length = 6;
			p->var.green.length = 6;
			p->var.blue.length = 6;
			break;
		case 16:
			p->var.red.offset = 11;
			p->var.green.offset = 5;
			p->var.blue.offset = 0;
			p->var.red.length = 5;
			p->var.green.length = 6;
			p->var.blue.length = 5;
			break;
		case 32:
			p->var.red.offset = 16;
			p->var.green.offset = 8;
			p->var.blue.offset = 0;
			p->var.red.length = 8;
			p->var.green.length = 8;
			p->var.blue.length = 8;
			break;
		default:
			return -EINVAL;
	}

	/* convert from picoseconds to MHz */
	p->vclk = 1000000/var->pixclock;

	if (p->bpp == 32)
		p->vclk *=2;

	p->hres = var->xres;
	vres = p->vres = var->yres;

	/* See if requested resolution is larger than flat panel */
	if (p->hres > i->nativex && flatpanel) {
		return -EINVAL;
	}

	/* See if requested resolution fits in available memory */
	if (p->hres * p->vres * p->bpp/8 > i->memsize) {
		return -EINVAL;
	}

	vfront = var->upper_margin;
	vback =	var->lower_margin;
	vsync =	var->vsync_len;

	/* Compute horizontal and vertical VGA CRTC timing values */
	if (var->vmode & FB_VMODE_INTERLACED) {
		vres /= 2;
		vfront /=2;
		vback /=2;
		vsync /=2;
	}

	if (var->vmode & FB_VMODE_DOUBLE) {
		vres *= 2;
		vfront *=2;
		vback *=2;
		vsync *=2;
	}

	p->htotal = (p->hres + var->left_margin + var->right_margin + var->hsync_len)/8 - 10;
	p->hdispend = p->hres/8 - 1;
	p->hsyncstart = (p->hres + var->right_margin)/8;
	p->hsyncend = var->hsync_len/8;
	p->hblankstart = p->hdispend + 1;
	p->hblankend = p->htotal + 5;

	p->vtotal = vres + vfront + vback + vsync - 2;
	p->vdispend = vres - 1;
	p->vsyncstart = vres + vback;
	p->vsyncend = vsync;
	p->vblankstart = vres;
	p->vblankend = p->vtotal + 2;

	debug("exit\n");

	return 0;
}


/* Fill in var from info */
static int trident_encode_var(struct fb_var_screeninfo *var,
				  const void *par,
				  struct fb_info_gen *info)
{
	struct tridentfb_par * p = (struct tridentfb_par *)par;
	debug("enter\n");
	*var = p->var;
	var->bits_per_pixel = p->bpp;
	debug("exit\n");
	return 0;
}

/* Fill in par from hardware */
static void trident_get_par(void *par, struct fb_info_gen *info)
{
	struct tridentfb_par * p = (struct tridentfb_par *)par;
	struct tridentfb_info * i = (struct tridentfb_info *)info;

	debug("enter\n");
	*p = i->currentmode;
	debug("exit\n");
}

/* Pan the display */
static int trident_pan_display(const struct fb_var_screeninfo *var,
				   struct fb_info_gen *info)
{
	unsigned int offset;
	struct tridentfb_info * i = (struct tridentfb_info *)info;

	debug("enter\n");

	offset = (var->xoffset + (var->yoffset * var->xres))
			* var->bits_per_pixel/32;
	i->currentmode.var.xoffset = var->xoffset;
	i->currentmode.var.yoffset = var->yoffset;
	set_screen_start(offset);
	debug("exit\n");
	return 0;
}

/* Set the hardware from par */
static void trident_set_par(const void *par, struct fb_info_gen *info)
{
	struct tridentfb_par * p = (struct tridentfb_par *)par;
	struct tridentfb_info * i = (struct tridentfb_info *)info;
	unsigned char tmp;
	debug("enter\n");

	i->currentmode = *p;
	enable_mmio();
	crtc_unlock();

	write3CE(CyberControl,8);
	if (flatpanel && p->hres < i->nativex) {
		/*
		 * on flat panels with native size larger
		 * than requested resolution decide whether
		 * we stretch or center
		 */
		t_outb(0xEB,0x3C2);
		write3CE(CyberControl,0x81);
		if (center) 
			screen_center();
		else if (stretch)
			screen_stretch();

	} else {
		t_outb(0x2B,0x3C2);
		write3CE(CyberControl,8);
	}

	/* vertical timing values */
	write3X4(CRTVTotal, p->vtotal & 0xFF);
	write3X4(CRTVDispEnd, p->vdispend & 0xFF);
	write3X4(CRTVSyncStart, p->vsyncstart & 0xFF);
	write3X4(CRTVSyncEnd, (p->vsyncend & 0x0F));
	write3X4(CRTVBlankStart, p->vblankstart & 0xFF);
	write3X4(CRTVBlankEnd, 0/*p->vblankend & 0xFF*/);

	/* horizontal timing values */
	write3X4(CRTHTotal, p->htotal & 0xFF);
	write3X4(CRTHDispEnd, p->hdispend & 0xFF);
	write3X4(CRTHSyncStart, p->hsyncstart & 0xFF);
	write3X4(CRTHSyncEnd, (p->hsyncend & 0x1F) | ((p->hblankend & 0x20)<<2));
	write3X4(CRTHBlankStart, p->hblankstart & 0xFF);
	write3X4(CRTHBlankEnd, 0/*(p->hblankend & 0x1F)*/);

	/* higher bits of vertical timing values */
	tmp = 0x10;
	if (p->vtotal & 0x100) tmp |= 0x01;
	if (p->vdispend & 0x100) tmp |= 0x02;
	if (p->vsyncstart & 0x100) tmp |= 0x04;
	if (p->vblankstart & 0x100) tmp |= 0x08;

	if (p->vtotal & 0x200) tmp |= 0x20;