controlfb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

{
	unsigned long p0, p1, p2, k, l, m, n, min;

	if (clk > (CONTROL_PIXCLOCK_BASE << 3))
		return 1;

	p2 = ((clk << 4) < CONTROL_PIXCLOCK_BASE)? 3: 2;
	l = clk << p2;
	p0 = 0;
	p1 = 0;
	for (k = 1, min = l; k < 32; k++) {
		unsigned long rem;

		m = CONTROL_PIXCLOCK_BASE * k;
		n = m / l;
		rem = m % l;
		if (n && (n < 128) && rem < min) {
			p0 = k;
			p1 = n;
			min = rem;
		}
	}
	if (!p0 || !p1)
		return 1;

	param[0] = p0;
	param[1] = p1;
	param[2] = p2;

	return 0;
}


/*
 * This routine takes a user-supplied var, and picks the best vmode/cmode
 * from it.
 */

static int control_var_to_par(struct fb_var_screeninfo *var,
	struct fb_par_control *par, const struct fb_info *fb_info)
{
	int cmode, piped_diff, hstep;
	unsigned hperiod, hssync, hsblank, hesync, heblank, piped, heq, hlfln,
		 hserr, vperiod, vssync, vesync, veblank, vsblank, vswin, vewin;
	unsigned long pixclock;
	struct fb_info_control *p = (struct fb_info_control *) fb_info;
	struct control_regvals *r = &par->regvals;

	switch (var->bits_per_pixel) {
	case 8:
		par->cmode = CMODE_8;
		if (p->total_vram > 0x200000) {
			r->mode = 3;
			r->radacal_ctrl = 0x20;
			piped_diff = 13;
		} else {
			r->mode = 2;
			r->radacal_ctrl = 0x10;
			piped_diff = 9;
		}
		break;
	case 15:
	case 16:
		par->cmode = CMODE_16;
		if (p->total_vram > 0x200000) {
			r->mode = 2;
			r->radacal_ctrl = 0x24;
			piped_diff = 5;
		} else {
			r->mode = 1;
			r->radacal_ctrl = 0x14;
			piped_diff = 3;
		}
		break;
	case 32:
		par->cmode = CMODE_32;
		if (p->total_vram > 0x200000) {
			r->mode = 1;
			r->radacal_ctrl = 0x28;
		} else {
			r->mode = 0;
			r->radacal_ctrl = 0x18;
		}
		piped_diff = 1;
		break;
	default:
		return -EINVAL;
	}

	/*
	 * adjust xres and vxres so that the corresponding memory widths are
	 * 32-byte aligned
	 */
	hstep = 31 >> par->cmode;
	par->xres = (var->xres + hstep) & ~hstep;
	par->vxres = (var->xres_virtual + hstep) & ~hstep;
	par->xoffset = (var->xoffset + hstep) & ~hstep;
	if (par->vxres < par->xres)
		par->vxres = par->xres;
	par->pitch = par->vxres << par->cmode;

	par->yres = var->yres;
	par->vyres = var->yres_virtual;
	par->yoffset = var->yoffset;
	if (par->vyres < par->yres)
		par->vyres = par->yres;

	par->sync = var->sync;

	if (par->pitch * par->vyres + CTRLFB_OFF > p->total_vram)
		return -EINVAL;

	if (par->xoffset + par->xres > par->vxres)
		par->xoffset = par->vxres - par->xres;
	if (par->yoffset + par->yres > par->vyres)
		par->yoffset = par->vyres - par->yres;

	pixclock = (var->pixclock < CONTROL_PIXCLOCK_MIN)? CONTROL_PIXCLOCK_MIN:
		   var->pixclock;
	if (calc_clock_params(pixclock, r->clock_params))
		return -EINVAL;

	hperiod = ((var->left_margin + par->xres + var->right_margin
		    + var->hsync_len) >> 1) - 2;
	hssync = hperiod + 1;
	hsblank = hssync - (var->right_margin >> 1);
	hesync = (var->hsync_len >> 1) - 1;
	heblank = (var->left_margin >> 1) + hesync;
	piped = heblank - piped_diff;
	heq = var->hsync_len >> 2;
	hlfln = (hperiod+2) >> 1;
	hserr = hssync-hesync;
	vperiod = (var->vsync_len + var->lower_margin + par->yres
		   + var->upper_margin) << 1;
	vssync = vperiod - 2;
	vesync = (var->vsync_len << 1) - vperiod + vssync;
	veblank = (var->upper_margin << 1) + vesync;
	vsblank = vssync - (var->lower_margin << 1);
	vswin = (vsblank+vssync) >> 1;
	vewin = (vesync+veblank) >> 1;

	r->regs[0] = vswin;
	r->regs[1] = vsblank;
	r->regs[2] = veblank;
	r->regs[3] = vewin;
	r->regs[4] = vesync;
	r->regs[5] = vssync;
	r->regs[6] = vperiod;
	r->regs[7] = piped;
	r->regs[8] = hperiod;
	r->regs[9] = hsblank;
	r->regs[10] = heblank;
	r->regs[11] = hesync;
	r->regs[12] = hssync;
	r->regs[13] = heq;
	r->regs[14] = hlfln;
	r->regs[15] = hserr;

	if (par->xres >= 1280 && par->cmode >= CMODE_16)
		par->ctrl = 0x7f;
	else
		par->ctrl = 0x3b;

	if (mac_var_to_vmode(var, &par->vmode, &cmode))
		par->vmode = 0;

	return 0;
}


/*
 * Convert hardware data in par to an fb_var_screeninfo
 */

static void control_par_to_var(struct fb_par_control *par, struct fb_var_screeninfo *var)
{
	struct control_regints *rv;
	
	rv = (struct control_regints *) par->regvals.regs;
	
	memset(var, 0, sizeof(*var));
	var->xres = par->xres;
	var->yres = par->yres;
	var->xres_virtual = par->vxres;
	var->yres_virtual = par->vyres;
	var->xoffset = par->xoffset;
	var->yoffset = par->yoffset;
	
	switch(par->cmode) {
	default:
	case CMODE_8:
		var->bits_per_pixel = 8;
		var->red.length = 8;
		var->green.length = 8;
		var->blue.length = 8;
		break;
	case CMODE_16:	/* RGB 555 */
		var->bits_per_pixel = 16;
		var->red.offset = 10;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 5;
		var->blue.length = 5;
		break;
	case CMODE_32:	/* RGB 888 */
		var->bits_per_pixel = 32;
		var->red.offset = 16;
		var->red.length = 8;
		var->green.offset = 8;
		var->green.length = 8;
		var->blue.length = 8;
		var->transp.offset = 24;
		var->transp.length = 8;
		break;
	}
	var->height = -1;
	var->width = -1;
	var->vmode = FB_VMODE_NONINTERLACED;

	var->left_margin = (rv->heblank - rv->hesync) << 1;
	var->right_margin = (rv->hssync - rv->hsblank) << 1;
	var->hsync_len = (rv->hperiod + 2 - rv->hssync + rv->hesync) << 1;

	var->upper_margin = (rv->veblank - rv->vesync) >> 1;
	var->lower_margin = (rv->vssync - rv->vsblank) >> 1;
	var->vsync_len = (rv->vperiod - rv->vssync + rv->vesync) >> 1;

	var->sync = par->sync;

	/*
	 * 10^12 * clock_params[0] / (3906400 * clock_params[1]
	 *			      * 2^clock_params[2])
	 * (10^12 * clock_params[0] / (3906400 * clock_params[1]))
	 * >> clock_params[2]
	 */
	/* (255990.17 * clock_params[0] / clock_params[1]) >> clock_params[2] */
	var->pixclock = CONTROL_PIXCLOCK_BASE * par->regvals.clock_params[0];
	var->pixclock /= par->regvals.clock_params[1];
	var->pixclock >>= par->regvals.clock_params[2];
}


/*
 * init fix according to given par
 */
static void control_par_to_fix(struct fb_par_control *par, struct fb_fix_screeninfo *fix,
	struct fb_info_control *p)
{
	memset(fix, 0, sizeof(*fix));
	strcpy(fix->id, "control");
	fix->mmio_start = p->control_regs_phys;
	fix->mmio_len = sizeof(struct control_regs);
	fix->type = FB_TYPE_PACKED_PIXELS;
	
	fix->xpanstep = 32 >> par->cmode;
	fix->ypanstep = 1;

	fix->smem_start = p->frame_buffer_phys + CTRLFB_OFF;
	fix->smem_len = p->total_vram - CTRLFB_OFF;
	fix->visual = (par->cmode == CMODE_8) ?
		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_DIRECTCOLOR;
	fix->line_length = par->pitch;
}

/*
 * initialize a portion of struct display which low level driver is responsible
 * for.
 */
static void control_par_to_display(struct fb_par_control *par,
  struct display *disp, struct fb_fix_screeninfo *fix, struct fb_info_control *p)
{
	disp->type = fix->type;
	disp->can_soft_blank = 1;
	disp->scrollmode = SCROLL_YNOMOVE | SCROLL_YNOPARTIAL;
	disp->ypanstep = fix->ypanstep;
	disp->ywrapstep = fix->ywrapstep;

	control_par_to_var(par, &disp->var);
	disp->screen_base = (char *) p->frame_buffer + CTRLFB_OFF;
	disp->visual = fix->visual;
	disp->line_length = fix->line_length;
	control_set_dispsw(disp, par->cmode, p);
}


/*
 * our own _revc() routines since generic routines don't work for DIRECT Color
 * devices like control
 */
static void control_cfb16_revc(struct display *p, int xx, int yy)
{
    u8 *dest;
    int bytes = p->next_line, rows;

    dest = p->screen_base + yy * fontheight(p) * bytes + xx * fontwidth(p)*2;
    for (rows = fontheight(p); rows--; dest += bytes) {
       switch (fontwidth(p)) {
       case 16:
           ((u32 *)dest)[6] ^= 0x3def3def; ((u32 *)dest)[7] ^= 0x3def3def;
           /* FALL THROUGH */
       case 12:
           ((u32 *)dest)[4] ^= 0x3def3def; ((u32 *)dest)[5] ^= 0x3def3def;
           /* FALL THROUGH */
       case 8:
           ((u32 *)dest)[2] ^= 0x3def3def; ((u32 *)dest)[3] ^= 0x3def3def;
           /* FALL THROUGH */
       case 4:
           ((u32 *)dest)[0] ^= 0x3def3def; ((u32 *)dest)[1] ^= 0x3def3def;
       }
    }
}

static void control_cfb32_revc(struct display *p, int xx, int yy)
{
    u8 *dest;
    int bytes = p->next_line, rows;

    dest = p->screen_base + yy * fontheight(p) * bytes + xx * fontwidth(p) * 4;
    for (rows = fontheight(p); rows--; dest += bytes) {
       switch (fontwidth(p)) {
       case 16:
           ((u32 *)dest)[12] ^= 0x0f0f0f0f; ((u32 *)dest)[13] ^= 0x0f0f0f0f;
           ((u32 *)dest)[14] ^= 0x0f0f0f0f; ((u32 *)dest)[15] ^= 0x0f0f0f0f;
           /* FALL THROUGH */
       case 12:
           ((u32 *)dest)[8] ^= 0x0f0f0f0f; ((u32 *)dest)[9] ^= 0x0f0f0f0f;
           ((u32 *)dest)[10] ^= 0x0f0f0f0f; ((u32 *)dest)[11] ^= 0x0f0f0f0f;
           /* FALL THROUGH */
       case 8:
           ((u32 *)dest)[4] ^= 0x0f0f0f0f; ((u32 *)dest)[5] ^= 0x0f0f0f0f;
           ((u32 *)dest)[6] ^= 0x0f0f0f0f; ((u32 *)dest)[7] ^= 0x0f0f0f0f;
           /* FALL THROUGH */
       case 4:
           ((u32 *)dest)[0] ^= 0x0f0f0f0f; ((u32 *)dest)[1] ^= 0x0f0f0f0f;
           ((u32 *)dest)[2] ^= 0x0f0f0f0f; ((u32 *)dest)[3] ^= 0x0f0f0f0f;
           /* FALL THROUGH */
       }
    }
}

static struct display_switch control_cfb16 = {
    setup:		fbcon_cfb16_setup,
    bmove:		fbcon_cfb16_bmove,
    clear:		fbcon_cfb16_clear,
    putc:		fbcon_cfb16_putc,
    putcs:		fbcon_cfb16_putcs,
    revc:		control_cfb16_revc,
    clear_margins:	fbcon_cfb16_clear_margins,
    fontwidthmask:	FONTWIDTH(4)|FONTWIDTH(8)|FONTWIDTH(12)|FONTWIDTH(16)
};

static struct display_switch control_cfb32 = {
    setup:		fbcon_cfb32_setup,
    bmove:		fbcon_cfb32_bmove,
    clear:		fbcon_cfb32_clear,
    putc:		fbcon_cfb32_putc,
    putcs:		fbcon_cfb32_putcs,
    revc:		control_cfb32_revc,
    clear_margins:	fbcon_cfb32_clear_margins,
    fontwidthmask:	FONTWIDTH(4)|FONTWIDTH(8)|FONTWIDTH(12)|FONTWIDTH(16)
};


/*
 * Set struct dispsw according to given cmode
 */
static void control_set_dispsw(struct display *disp, int cmode, struct fb_info_control *p)
{
	switch (cmode) {
#ifdef FBCON_HAS_CFB8
		case CMODE_8:
			disp->dispsw = &fbcon_cfb8;
			break;
#endif
#ifdef FBCON_HAS_CFB16
		case CMODE_16:
			disp->dispsw = &control_cfb16;
			disp->dispsw_data = p->fbcon_cmap.cfb16;
			break;
#endif
#ifdef FBCON_HAS_CFB32
		case CMODE_32:
			disp->dispsw = &control_cfb32;
			disp->dispsw_data = p->fbcon_cmap.cfb32;
			break;
#endif
		default:
			disp->dispsw = &fbcon_dummy;
			break;
	}
}


/*
 * Set misc info vars for this driver
 */
static void __init control_init_info(struct fb_info *info, struct fb_info_control *p)
{
	strcpy(info->modename, "control");
	info->node = -1;	/* ??? danj */
	info->fbops = &controlfb_ops;
	info->disp = &p->display;
	strcpy(info->fontname, fontname);
	info->changevar = NULL;
	info->switch_con = &controlfb_switch;
	info->updatevar = &controlfb_updatevar;
	info->blank = &controlfb_blank;
}


static void control_cleanup(void)
{
	struct fb_info_control	*p = control_fb;

	if (!p)
		return;

	if (p->cmap_regs)
		iounmap(p->cmap_regs);
	if (p->control_regs)
		iounmap(p->control_regs);
	if (p->frame_buffer) {
		if (p->control_use_bank2)
			p->frame_buffer -= 0x600000;
		iounmap(p->frame_buffer);
	}
	if (p->cmap_regs_phys)
		release_mem_region(p->cmap_regs_phys, 0x1000);
	if (p->control_regs_phys)
		release_mem_region(p->control_regs_phys, p->control_regs_size);
	if (p->fb_orig_base)
		release_mem_region(p->fb_orig_base, p->fb_orig_size);
	kfree(p);
}


/*
 * Parse user speficied options (`video=controlfb:')
 */
void __init control_setup(char *options)
{
	char *this_opt;

	if (!options || !*options)
		return;

	while ((this_opt = strsep(&options, ",")) != NULL) {
		if (!strncmp(this_opt, "font:", 5)) {
			char *p;
			int i;

			p = this_opt +5;
			for (i = 0; i < sizeof(fontname) - 1; i++)
				if (!*p || *p == ' ' || *p == ',')
					break;
			memcpy(fontname, this_opt + 5, i);
			fontname[i] = 0;
		} else if (!strncmp(this_opt, "vmode:", 6)) {
			int vmode = simple_strtoul(this_opt+6, NULL, 0);
			if (vmode > 0 && vmode <= VMODE_MAX &&
			    control_mac_modes[vmode - 1].m[1] >= 0)
				default_vmode = vmode;
		} else if (!strncmp(this_opt, "cmode:", 6)) {
			int depth = simple_strtoul(this_opt+6, NULL, 0);
			switch (depth) {
			 case CMODE_8:
			 case CMODE_16:
			 case CMODE_32:
			 	default_cmode = depth;
			 	break;
			 case 8:
				default_cmode = CMODE_8;
				break;
			 case 15:
			 case 16:
				default_cmode = CMODE_16;
				break;
			 case 24:
			 case 32:
				default_cmode = CMODE_32;
				break;
			}
		}
	}
}