fbcon.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

    }
#endif /* CONFIG_MAC */

#if defined(__arm__) && defined(IRQ_VSYNCPULSE)
    cursor_blink_rate = ARM_CURSOR_BLINK_RATE;
    irqres = request_irq(IRQ_VSYNCPULSE, fbcon_vbl_handler, SA_SHIRQ,
			 "console/cursor", fbcon_vbl_handler);
#endif

    if (irqres) {
	use_timer_cursor = 1;
	cursor_blink_rate = DEFAULT_CURSOR_BLINK_RATE;
	cursor_timer.expires = jiffies+HZ/50;
	add_timer(&cursor_timer);
    }

#ifdef CONFIG_PM
    pm_fbcon = pm_register(PM_SYS_DEV, PM_SYS_VGA, pm_fbcon_request);
#endif

    return display_desc;
}


static void fbcon_init(struct vc_data *conp, int init)
{
    int unit = conp->vc_num;
    struct fb_info *info;

    /* on which frame buffer will we open this console? */
    info = registered_fb[(int)con2fb_map[unit]];

    info->changevar = &fbcon_changevar;
    fb_display[unit] = *(info->disp);	/* copy from default */
    DPRINTK("mode:   %s\n",info->modename);
    DPRINTK("visual: %d\n",fb_display[unit].visual);
    DPRINTK("res:    %dx%d-%d\n",fb_display[unit].var.xres,
	                     fb_display[unit].var.yres,
	                     fb_display[unit].var.bits_per_pixel);
    fb_display[unit].conp = conp;
    fb_display[unit].fb_info = info;
    /* clear out the cmap so we don't have dangling pointers */
    fb_display[unit].cmap.len = 0;
    fb_display[unit].cmap.red = 0;
    fb_display[unit].cmap.green = 0;
    fb_display[unit].cmap.blue = 0;
    fb_display[unit].cmap.transp = 0;
    fbcon_setup(unit, init, !init);
    /* Must be done after fbcon_setup to prevent excess updates */
    conp->vc_display_fg = &info->display_fg;
    if (!info->display_fg)
        info->display_fg = conp;
}


static void fbcon_deinit(struct vc_data *conp)
{
    int unit = conp->vc_num;
    struct display *p = &fb_display[unit];

    fbcon_free_font(p);
    p->dispsw = &fbcon_dummy;
    p->conp = 0;
}


static int fbcon_changevar(int con)
{
    if (fb_display[con].conp)
	    fbcon_setup(con, 0, 0);
    return 0;
}


static __inline__ void updatescrollmode(struct display *p)
{
    int m;
    if (p->scrollmode & __SCROLL_YFIXED)
    	return;
    if (divides(p->ywrapstep, fontheight(p)) &&
	divides(fontheight(p), p->var.yres_virtual))
	m = __SCROLL_YWRAP;
    else if (divides(p->ypanstep, fontheight(p)) &&
	     p->var.yres_virtual >= p->var.yres+fontheight(p))
	m = __SCROLL_YPAN;
    else if (p->scrollmode & __SCROLL_YNOMOVE)
    	m = __SCROLL_YREDRAW;
    else
	m = __SCROLL_YMOVE;
    p->scrollmode = (p->scrollmode & ~__SCROLL_YMASK) | m;
}

static void fbcon_font_widths(struct display *p)
{
    int i;
    
    p->_fontwidthlog = 0;
    for (i = 2; i <= 6; i++)
    	if (fontwidth(p) == (1 << i))
	    p->_fontwidthlog = i;
    p->_fontheightlog = 0;
    for (i = 2; i <= 6; i++)
    	if (fontheight(p) == (1 << i))
	    p->_fontheightlog = i;
}

#define fontwidthvalid(p,w) ((p)->dispsw->fontwidthmask & FONTWIDTH(w))

static void fbcon_setup(int con, int init, int logo)
{
    struct display *p = &fb_display[con];
    struct vc_data *conp = p->conp;
    int nr_rows, nr_cols;
    int old_rows, old_cols;
    unsigned short *save = NULL, *r, *q;
    int i, charcnt = 256;
    struct fbcon_font_desc *font;
    
    if (con != fg_console || (p->fb_info->flags & FBINFO_FLAG_MODULE) ||
        p->type == FB_TYPE_TEXT)
    	logo = 0;

    p->var.xoffset = p->var.yoffset = p->yscroll = 0;  /* reset wrap/pan */

    if (con == fg_console && p->type != FB_TYPE_TEXT) {   
	if (fbcon_softback_size) {
	    if (!softback_buf) {
		softback_buf = (unsigned long)kmalloc(fbcon_softback_size, GFP_KERNEL);
		if (!softback_buf) {
    	            fbcon_softback_size = 0;
    	            softback_top = 0;
    		}
    	    }
	} else {
	    if (softback_buf) {
		kfree((void *)softback_buf);
		softback_buf = 0;
		softback_top = 0;
	    }
	}
	if (softback_buf)
	    softback_in = softback_top = softback_curr = softback_buf;
	softback_lines = 0;
    }
    
    for (i = 0; i < MAX_NR_CONSOLES; i++)
    	if (i != con && fb_display[i].fb_info == p->fb_info &&
    	    fb_display[i].conp && fb_display[i].fontdata)
    		break;

    fbcon_free_font(p);    
    if (i < MAX_NR_CONSOLES) {
    	struct display *q = &fb_display[i];

        if (fontwidthvalid(p,fontwidth(q))) {
            /* If we are not the first console on this
               fb, copy the font from that console */
	    p->_fontwidth = q->_fontwidth;
	    p->_fontheight = q->_fontheight;
    	    p->_fontwidthlog = q->_fontwidthlog;
    	    p->_fontheightlog = q->_fontheightlog;
    	    p->fontdata = q->fontdata;
    	    p->userfont = q->userfont; 
    	    if (p->userfont) {
    		REFCOUNT(p->fontdata)++;
    		charcnt = FNTCHARCNT(p->fontdata);
    	    }
    	    con_copy_unimap(con, i);
    	}
    }

    if (!p->fontdata) {
        if (!p->fb_info->fontname[0] ||
	    !(font = fbcon_find_font(p->fb_info->fontname)))
	        font = fbcon_get_default_font(p->var.xres, p->var.yres);
        p->_fontwidth = font->width;
        p->_fontheight = font->height;
        p->fontdata = font->data;
        fbcon_font_widths(p);
    }
    
    if (!fontwidthvalid(p,fontwidth(p))) {
#if defined(CONFIG_FBCON_MAC) && defined(CONFIG_MAC)
	if (MACH_IS_MAC)
	    /* ++Geert: hack to make 6x11 fonts work on mac */
	    p->dispsw = &fbcon_mac;
	else
#endif
	{
	    /* ++Geert: changed from panic() to `correct and continue' */
	    printk(KERN_ERR "fbcon_setup: No support for fontwidth %d\n", fontwidth(p));
	    p->dispsw = &fbcon_dummy;
	}
    }
    if (p->dispsw->set_font)
    	p->dispsw->set_font(p, fontwidth(p), fontheight(p));
    updatescrollmode(p);
    
    old_cols = conp->vc_cols;
    old_rows = conp->vc_rows;
    
    nr_cols = p->var.xres/fontwidth(p);
    nr_rows = p->var.yres/fontheight(p);
    
    if (logo) {
    	/* Need to make room for the logo */
	int cnt;
	int step;
    
    	logo_lines = (LOGO_H + fontheight(p) - 1) / fontheight(p);
    	q = (unsigned short *)(conp->vc_origin + conp->vc_size_row * old_rows);
    	step = logo_lines * old_cols;
    	for (r = q - logo_lines * old_cols; r < q; r++)
    	    if (scr_readw(r) != conp->vc_video_erase_char)
    	    	break;
	if (r != q && nr_rows >= old_rows + logo_lines) {
    	    save = kmalloc(logo_lines * nr_cols * 2, GFP_KERNEL);
    	    if (save) {
    	        int i = old_cols < nr_cols ? old_cols : nr_cols;
    	    	scr_memsetw(save, conp->vc_video_erase_char, logo_lines * nr_cols * 2);
    	    	r = q - step;
    	    	for (cnt = 0; cnt < logo_lines; cnt++, r += i)
    	    		scr_memcpyw(save + cnt * nr_cols, r, 2 * i);
    	    	r = q;
    	    }
    	}
    	if (r == q) {
    	    /* We can scroll screen down */
	    r = q - step - old_cols;
    	    for (cnt = old_rows - logo_lines; cnt > 0; cnt--) {
    	    	scr_memcpyw(r + step, r, conp->vc_size_row);
    	    	r -= old_cols;
    	    }
    	    if (!save) {
	    	conp->vc_y += logo_lines;
    		conp->vc_pos += logo_lines * conp->vc_size_row;
    	    }
    	}
    	scr_memsetw((unsigned short *)conp->vc_origin,
		    conp->vc_video_erase_char, 
		    conp->vc_size_row * logo_lines);
    }
    
    /*
     *  ++guenther: console.c:vc_allocate() relies on initializing
     *  vc_{cols,rows}, but we must not set those if we are only
     *  resizing the console.
     */
    if (init) {
	conp->vc_cols = nr_cols;
	conp->vc_rows = nr_rows;
    }
    p->vrows = p->var.yres_virtual/fontheight(p);
    if ((p->var.yres % fontheight(p)) &&
	(p->var.yres_virtual % fontheight(p) < p->var.yres % fontheight(p)))
	p->vrows--;
    conp->vc_can_do_color = p->var.bits_per_pixel != 1;
    conp->vc_complement_mask = conp->vc_can_do_color ? 0x7700 : 0x0800;
    if (charcnt == 256) {
    	conp->vc_hi_font_mask = 0;
    	p->fgshift = 8;
    	p->bgshift = 12;
    	p->charmask = 0xff;
    } else {
    	conp->vc_hi_font_mask = 0x100;
    	if (conp->vc_can_do_color)
	    conp->vc_complement_mask <<= 1;
    	p->fgshift = 9;
    	p->bgshift = 13;
    	p->charmask = 0x1ff;
    }

    if (p->dispsw == &fbcon_dummy)
	printk(KERN_WARNING "fbcon_setup: type %d (aux %d, depth %d) not "
	       "supported\n", p->type, p->type_aux, p->var.bits_per_pixel);
    p->dispsw->setup(p);

    p->fgcol = p->var.bits_per_pixel > 2 ? 7 : (1<<p->var.bits_per_pixel)-1;
    p->bgcol = 0;

    if (!init) {
	if (conp->vc_cols != nr_cols || conp->vc_rows != nr_rows)
	    vc_resize_con(nr_rows, nr_cols, con);
	else if (CON_IS_VISIBLE(conp) &&
		 vt_cons[conp->vc_num]->vc_mode == KD_TEXT) {
	    if (p->dispsw->clear_margins)
		p->dispsw->clear_margins(conp, p, 0);
	    update_screen(con);
	}
	if (save) {
    	    q = (unsigned short *)(conp->vc_origin + conp->vc_size_row * old_rows);
	    scr_memcpyw(q, save, logo_lines * nr_cols * 2);
	    conp->vc_y += logo_lines;
    	    conp->vc_pos += logo_lines * conp->vc_size_row;
    	    kfree(save);
	}
    }
	
    if (logo) {
	logo_shown = -2;
    	conp->vc_top = logo_lines;
    }
    
    if (con == fg_console && softback_buf) {
    	int l = fbcon_softback_size / conp->vc_size_row;
    	if (l > 5)
    	    softback_end = softback_buf + l * conp->vc_size_row;
    	else {
    	    /* Smaller scrollback makes no sense, and 0 would screw
    	       the operation totally */
    	    softback_top = 0;
    	}
    }
}


/* ====================================================================== */

/*  fbcon_XXX routines - interface used by the world
 *
 *  This system is now divided into two levels because of complications
 *  caused by hardware scrolling. Top level functions:
 *
 *	fbcon_bmove(), fbcon_clear(), fbcon_putc()
 *
 *  handles y values in range [0, scr_height-1] that correspond to real
 *  screen positions. y_wrap shift means that first line of bitmap may be
 *  anywhere on this display. These functions convert lineoffsets to
 *  bitmap offsets and deal with the wrap-around case by splitting blits.
 *
 *	fbcon_bmove_physical_8()    -- These functions fast implementations
 *	fbcon_clear_physical_8()    -- of original fbcon_XXX fns.
 *	fbcon_putc_physical_8()	    -- (fontwidth != 8) may be added later
 *
 *  WARNING:
 *
 *  At the moment fbcon_putc() cannot blit across vertical wrap boundary
 *  Implies should only really hardware scroll in rows. Only reason for
 *  restriction is simplicity & efficiency at the moment.
 */

static __inline__ int real_y(struct display *p, int ypos)
{
    int rows = p->vrows;

    ypos += p->yscroll;
    return ypos < rows ? ypos : ypos-rows;
}


static void fbcon_clear(struct vc_data *conp, int sy, int sx, int height,
			int width)
{
    int unit = conp->vc_num;
    struct display *p = &fb_display[unit];
    u_int y_break;
    int redraw_cursor = 0;

    if (!p->can_soft_blank && console_blanked)
	return;

    if (!height || !width)
	return;

    if ((sy <= p->cursor_y) && (p->cursor_y < sy+height) &&
	(sx <= p->cursor_x) && (p->cursor_x < sx+width)) {
	cursor_undrawn();
	redraw_cursor = 1;
    }

    /* Split blits that cross physical y_wrap boundary */

    y_break = p->vrows-p->yscroll;
    if (sy < y_break && sy+height-1 >= y_break) {
	u_int b = y_break-sy;
	p->dispsw->clear(conp, p, real_y(p, sy), sx, b, width);
	p->dispsw->clear(conp, p, real_y(p, sy+b), sx, height-b, width);
    } else
	p->dispsw->clear(conp, p, real_y(p, sy), sx, height, width);

    if (redraw_cursor)
	vbl_cursor_cnt = CURSOR_DRAW_DELAY;
}


static void fbcon_putc(struct vc_data *conp, int c, int ypos, int xpos)
{
    int unit = conp->vc_num;
    struct display *p = &fb_display[unit];
    int redraw_cursor = 0;

    if (!p->can_soft_blank && console_blanked)
	    return;
	    
    if (vt_cons[unit]->vc_mode != KD_TEXT)
    	    return;

    if ((p->cursor_x == xpos) && (p->cursor_y == ypos)) {
	    cursor_undrawn();
	    redraw_cursor = 1;
    }

    p->dispsw->putc(conp, p, c, real_y(p, ypos), xpos);

    if (redraw_cursor)
	    vbl_cursor_cnt = CURSOR_DRAW_DELAY;
}


static void fbcon_putcs(struct vc_data *conp, const unsigned short *s, int count,
		       int ypos, int xpos)
{
    int unit = conp->vc_num;
    struct display *p = &fb_display[unit];
    int redraw_cursor = 0;

    if (!p->can_soft_blank && console_blanked)
	    return;

    if (vt_cons[unit]->vc_mode != KD_TEXT)
    	    return;

    if ((p->cursor_y == ypos) && (xpos <= p->cursor_x) &&
	(p->cursor_x < (xpos + count))) {
	    cursor_undrawn();
	    redraw_cursor = 1;
    }
    p->dispsw->putcs(conp, p, s, count, real_y(p, ypos), xpos);
    if (redraw_cursor)
	    vbl_cursor_cnt = CURSOR_DRAW_DELAY;
}


static void fbcon_cursor(struct vc_data *conp, int mode)
{
    int unit = conp->vc_num;
    struct display *p = &fb_display[unit];
    int y = conp->vc_y;
    
    if (mode & CM_SOFTBACK) {
    	mode &= ~CM_SOFTBACK;
    	if (softback_lines) {
    	    if (y + softback_lines >= conp->vc_rows)
    		mode = CM_ERASE;
    	    else
    	        y += softback_lines;
    	}
    } else if (softback_lines)
        fbcon_set_origin(conp);

    /* do we have a hardware cursor ? */
    if (p->dispsw->cursor) {
	p->cursor_x = conp->vc_x;
	p->cursor_y = y;
	p->dispsw->cursor(p, mode, p->cursor_x, real_y(p, p->cursor_y));
	return;
    }

    /* Avoid flickering if there's no real change. */
    if (p->cursor_x == conp->vc_x && p->cursor_y == y &&
	(mode == CM_ERASE) == !cursor_on)
	return;

    cursor_on = 0;
    if (cursor_drawn && p->cursor_x < conp->vc_cols &&
	p->cursor_y < conp->vc_rows)