fbcon.c

h内核

/*
 *  linux/drivers/video/fbcon.c -- Low level frame buffer based console driver
 *
 *	Copyright (C) 1995 Geert Uytterhoeven
 *
 *
 *  This file is based on the original Amiga console driver (amicon.c):
 *
 *	Copyright (C) 1993 Hamish Macdonald
 *			   Greg Harp
 *	Copyright (C) 1994 David Carter [[e-mail]]
 *
 *	      with work by William Rucklidge ([e-mail])
 *			   Geert Uytterhoeven
 *			   Jes Sorensen ([e-mail])
 *			   Martin Apel
 *
 *  and on the original Atari console driver (atacon.c):
 *
 *	Copyright (C) 1993 Bjoern Brauel
 *			   Roman Hodek
 *
 *	      with work by Guenther Kelleter
 *			   Martin Schaller
 *			   Andreas Schwab
 *
 *  Hardware cursor support added by Emmanuel Marty ([e-mail])
 *  Smart redraw scrolling, arbitrary font width support, 512char font support
 *  and software scrollback added by 
 *                         Jakub Jelinek ([e-mail])
 *
 *  Random hacking by Martin Mares <[e-mail]>
 *
 *	2001 - Documented with DocBook
 *	- Brad Douglas <[e-mail]>
 *
 *  The low level operations for the various display memory organizations are
 *  now in separate source files.
 *
 *  Currently the following organizations are supported:
 *
 *    o afb			Amiga bitplanes
 *    o cfb{2,4,8,16,24,32}	Packed pixels
 *    o ilbm			Amiga interleaved bitplanes
 *    o iplan2p[248]		Atari interleaved bitplanes
 *    o mfb			Monochrome
 *    o vga			VGA characters/attributes
 *
 *  To do:
 *
 *    - Implement 16 plane mode (iplan2p16)
 *
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License.  See the file COPYING in the main directory of this archive for
 *  more details.
 */

#undef FBCONDEBUG

#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/delay.h>	/* MSch: for IRQ probe */
#include <linux/tty.h>
#include <linux/console.h>
#include <linux/string.h>
#include <linux/kd.h>
#include <linux/slab.h>
#include <linux/fb.h>
#include <linux/vt_kern.h>
#include <linux/selection.h>
#include <linux/font.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/crc32.h> /* For counting font checksums */
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#ifdef CONFIG_ATARI
#include <asm/atariints.h>
#endif
#ifdef CONFIG_MAC
#include <asm/macints.h>
#endif
#if defined(__mc68000__) || defined(CONFIG_APUS)
#include <asm/machdep.h>
#include <asm/setup.h>
#endif

#include "fbcon.h"

#ifdef FBCONDEBUG
#  define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt, __FUNCTION__ , ## args)
#else
#  define DPRINTK(fmt, args...)
#endif

enum {
	FBCON_LOGO_CANSHOW	= -1,	/* the logo can be shown */
	FBCON_LOGO_DRAW		= -2,	/* draw the logo to a console */
	FBCON_LOGO_DONTSHOW	= -3	/* do not show the logo */
};

struct display fb_display[MAX_NR_CONSOLES];
signed char con2fb_map[MAX_NR_CONSOLES];
signed char con2fb_map_boot[MAX_NR_CONSOLES];
static int logo_height;
static int logo_lines;
/* logo_shown is an index to vc_cons when >= 0; otherwise follows FBCON_LOGO
   enums.  */
static int logo_shown = FBCON_LOGO_CANSHOW;
/* Software scrollback */
int fbcon_softback_size = 32768;
static unsigned long softback_buf, softback_curr;
static unsigned long softback_in;
static unsigned long softback_top, softback_end;
static int softback_lines;
/* console mappings */
static int first_fb_vc;
static int last_fb_vc = MAX_NR_CONSOLES - 1;
static int fbcon_is_default = 1; 
/* font data */
static char fontname[40];

/* current fb_info */
static int info_idx = -1;

#define CM_SOFTBACK	(8)

#define advance_row(p, delta) (unsigned short *)((unsigned long)(p) + (delta) * vc->vc_size_row)

static void fbcon_free_font(struct display *);
static int fbcon_set_origin(struct vc_data *);

#define CURSOR_DRAW_DELAY		(1)

/* # VBL ints between cursor state changes */
#define ARM_CURSOR_BLINK_RATE		(10)
#define ATARI_CURSOR_BLINK_RATE		(42)
#define MAC_CURSOR_BLINK_RATE		(32)
#define DEFAULT_CURSOR_BLINK_RATE	(20)

static int vbl_cursor_cnt;

#define divides(a, b)	((!(a) || (b)%(a)) ? 0 : 1)

/*
 *  Interface used by the world
 */

static const char *fbcon_startup(void);
static void fbcon_init(struct vc_data *vc, int init);
static void fbcon_deinit(struct vc_data *vc);
static void fbcon_clear(struct vc_data *vc, int sy, int sx, int height,
			int width);
static void fbcon_putc(struct vc_data *vc, int c, int ypos, int xpos);
static void fbcon_putcs(struct vc_data *vc, const unsigned short *s,
			int count, int ypos, int xpos);
static void fbcon_clear_margins(struct vc_data *vc, int bottom_only);
static void fbcon_cursor(struct vc_data *vc, int mode);
static int fbcon_scroll(struct vc_data *vc, int t, int b, int dir,
			int count);
static void fbcon_bmove(struct vc_data *vc, int sy, int sx, int dy, int dx,
			int height, int width);
static int fbcon_switch(struct vc_data *vc);
static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch);
static int fbcon_set_palette(struct vc_data *vc, unsigned char *table);
static int fbcon_scrolldelta(struct vc_data *vc, int lines);

/*
 *  Internal routines
 */
static __inline__ int real_y(struct display *p, int ypos);
static __inline__ void ywrap_up(struct vc_data *vc, int count);
static __inline__ void ywrap_down(struct vc_data *vc, int count);
static __inline__ void ypan_up(struct vc_data *vc, int count);
static __inline__ void ypan_down(struct vc_data *vc, int count);
static void fbcon_bmove_rec(struct vc_data *vc, struct display *p, int sy, int sx,
			    int dy, int dx, int height, int width, u_int y_break);
static void fbcon_set_disp(struct fb_info *info, struct vc_data *vc);
static void fbcon_preset_disp(struct fb_info *info, int unit);
static void fbcon_redraw_move(struct vc_data *vc, struct display *p,
			      int line, int count, int dy);

#ifdef CONFIG_MAC
/*
 * On the Macintoy, there may or may not be a working VBL int. We need to probe
 */
static int vbl_detected;

static irqreturn_t fb_vbl_detect(int irq, void *dummy, struct pt_regs *fp)
{
	vbl_detected++;
	return IRQ_HANDLED;
}
#endif

static inline int fbcon_is_inactive(struct vc_data *vc, struct fb_info *info)
{
	return (info->state != FBINFO_STATE_RUNNING ||
		vt_cons[vc->vc_num]->vc_mode != KD_TEXT);
}

static inline int get_color(struct vc_data *vc, struct fb_info *info,
	      u16 c, int is_fg)
{
	int depth = fb_get_color_depth(info);
	int color = 0;

	if (console_blanked) {
		unsigned short charmask = vc->vc_hi_font_mask ? 0x1ff : 0xff;

		c = vc->vc_video_erase_char & charmask;
	}

	if (depth != 1)
		color = (is_fg) ? attr_fgcol((vc->vc_hi_font_mask) ? 9 : 8, c)
			: attr_bgcol((vc->vc_hi_font_mask) ? 13 : 12, c);

	switch (depth) {
	case 1:
	{
		/* 0 or 1 */
		int fg = (info->fix.visual != FB_VISUAL_MONO01) ? 1 : 0;
		int bg = (info->fix.visual != FB_VISUAL_MONO01) ? 0 : 1;

		if (console_blanked)
			fg = bg;

		color = (is_fg) ? fg : bg;
		break;
	}
	case 2:
		/*
		 * Scale down 16-colors to 4 colors. Default 4-color palette
		 * is grayscale.
		 */
		color /= 4;
		break;
	case 3:
		/*
		 * Last 8 entries of default 16-color palette is a more intense
		 * version of the first 8 (i.e., same chrominance, different
		 * luminance).
		 */
		color &= 7;
		break;
	}


	return color;
}

static void fb_flashcursor(void *private)
{
	struct fb_info *info = private;
	struct fbcon_ops *ops = info->fbcon_par;
	struct display *p;
	struct vc_data *vc = NULL;
	int c;
	int mode;

	if (ops->currcon != -1)
		vc = vc_cons[ops->currcon].d;

	if (!vc || !CON_IS_VISIBLE(vc) ||
	    fbcon_is_inactive(vc, info) ||
 	    registered_fb[con2fb_map[vc->vc_num]] != info)
		return;
	acquire_console_sem();
	p = &fb_display[vc->vc_num];
	c = scr_readw((u16 *) vc->vc_pos);
	mode = (!ops->cursor_flash || ops->cursor_state.enable) ?
		CM_ERASE : CM_DRAW;
	ops->cursor(vc, info, p, mode, get_color(vc, info, c, 1),
		    get_color(vc, info, c, 0));
	release_console_sem();
}

#if (defined(__arm__) && defined(IRQ_VSYNCPULSE)) || defined(CONFIG_ATARI) || defined(CONFIG_MAC)
static int cursor_blink_rate;
static irqreturn_t fb_vbl_handler(int irq, void *dev_id, struct pt_regs *fp)
{
	struct fb_info *info = dev_id;

	if (vbl_cursor_cnt && --vbl_cursor_cnt == 0) {
		schedule_work(&info->queue);	
		vbl_cursor_cnt = cursor_blink_rate; 
	}
	return IRQ_HANDLED;
}
#endif
	
static void cursor_timer_handler(unsigned long dev_addr)
{
	struct fb_info *info = (struct fb_info *) dev_addr;
	struct fbcon_ops *ops = info->fbcon_par;

	schedule_work(&info->queue);
	mod_timer(&ops->cursor_timer, jiffies + HZ/5);
}

int __init fb_console_setup(char *this_opt)
{
	char *options;
	int i, j;

	if (!this_opt || !*this_opt)
		return 0;

	while ((options = strsep(&this_opt, ",")) != NULL) {
		if (!strncmp(options, "font:", 5))
			strcpy(fontname, options + 5);
		
		if (!strncmp(options, "scrollback:", 11)) {
			options += 11;
			if (*options) {
				fbcon_softback_size = simple_strtoul(options, &options, 0);
				if (*options == 'k' || *options == 'K') {
					fbcon_softback_size *= 1024;
					options++;
				}
				if (*options != ',')
					return 0;
				options++;
			} else
				return 0;
		}
		
		if (!strncmp(options, "map:", 4)) {
			options += 4;
			if (*options)
				for (i = 0, j = 0; i < MAX_NR_CONSOLES; i++) {
					if (!options[j])
						j = 0;
					con2fb_map_boot[i] =
						(options[j++]-'0') % FB_MAX;
				}
			return 0;
		}

		if (!strncmp(options, "vc:", 3)) {
			options += 3;
			if (*options)
				first_fb_vc = simple_strtoul(options, &options, 10) - 1;
			if (first_fb_vc < 0)
				first_fb_vc = 0;
			if (*options++ == '-')
				last_fb_vc = simple_strtoul(options, &options, 10) - 1;
			fbcon_is_default = 0; 
		}	
	}
	return 0;
}

__setup("fbcon=", fb_console_setup);

static int search_fb_in_map(int idx)
{
	int i, retval = 0;

	for (i = 0; i < MAX_NR_CONSOLES; i++) {
		if (con2fb_map[i] == idx)
			retval = 1;
	}
	return retval;
}

static int search_for_mapped_con(void)
{
	int i, retval = 0;

	for (i = 0; i < MAX_NR_CONSOLES; i++) {
		if (con2fb_map[i] != -1)
			retval = 1;
	}
	return retval;
}

static int fbcon_takeover(int show_logo)
{
	int err, i;

	if (!num_registered_fb)
		return -ENODEV;

	if (!show_logo)
		logo_shown = FBCON_LOGO_DONTSHOW;

	for (i = first_fb_vc; i <= last_fb_vc; i++)
		con2fb_map[i] = info_idx;

	err = take_over_console(&fb_con, first_fb_vc, last_fb_vc,
				fbcon_is_default);
	if (err) {
		for (i = first_fb_vc; i <= last_fb_vc; i++) {
			con2fb_map[i] = -1;
		}
		info_idx = -1;
	}

	return err;
}

static void fbcon_prepare_logo(struct vc_data *vc, struct fb_info *info,
			       int cols, int rows, int new_cols, int new_rows)
{
	/* Need to make room for the logo */
	int cnt, erase = vc->vc_video_erase_char, step;
	unsigned short *save = NULL, *r, *q;

	/*
	 * remove underline attribute from erase character
	 * if black and white framebuffer.
	 */
	if (fb_get_color_depth(info) == 1)
		erase &= ~0x400;
	logo_height = fb_prepare_logo(info);
	logo_lines = (logo_height + vc->vc_font.height - 1) /
		vc->vc_font.height;
	q = (unsigned short *) (vc->vc_origin +
				vc->vc_size_row * rows);
	step = logo_lines * cols;
	for (r = q - logo_lines * cols; r < q; r++)
		if (scr_readw(r) != vc->vc_video_erase_char)
			break;
	if (r != q && new_rows >= rows + logo_lines) {
		save = kmalloc(logo_lines * new_cols * 2, GFP_KERNEL);
		if (save) {
			int i = cols < new_cols ? cols : new_cols;
			scr_memsetw(save, erase, logo_lines * new_cols * 2);
			r = q - step;
			for (cnt = 0; cnt < logo_lines; cnt++, r += i)
				scr_memcpyw(save + cnt * new_cols, r, 2 * i);
			r = q;
		}
	}
	if (r == q) {
		/* We can scroll screen down */
		r = q - step - cols;
		for (cnt = rows - logo_lines; cnt > 0; cnt--) {
			scr_memcpyw(r + step, r, vc->vc_size_row);
			r -= cols;
		}
		if (!save) {
			vc->vc_y += logo_lines;
			vc->vc_pos += logo_lines * vc->vc_size_row;
		}
	}
	scr_memsetw((unsigned short *) vc->vc_origin,
		    erase,
		    vc->vc_size_row * logo_lines);

	if (CON_IS_VISIBLE(vc) && vt_cons[vc->vc_num]->vc_mode == KD_TEXT) {
		fbcon_clear_margins(vc, 0);
		update_screen(vc->vc_num);
	}

	if (save) {
		q = (unsigned short *) (vc->vc_origin +
					vc->vc_size_row *
					rows);
		scr_memcpyw(q, save, logo_lines * new_cols * 2);
		vc->vc_y += logo_lines;
		vc->vc_pos += logo_lines * vc->vc_size_row;
		kfree(save);
	}

	if (logo_lines > vc->vc_bottom) {
		logo_shown = FBCON_LOGO_CANSHOW;
		printk(KERN_INFO
		       "fbcon_init: disable boot-logo (boot-logo bigger than screen).\n");
	} else if (logo_shown != FBCON_LOGO_DONTSHOW) {
		logo_shown = FBCON_LOGO_DRAW;
		vc->vc_top = logo_lines;
	}
}

#ifdef CONFIG_FB_TILEBLITTING
static void set_blitting_type(struct vc_data *vc, struct fb_info *info,
			      struct display *p)
{
	struct fbcon_ops *ops = info->fbcon_par;

	if ((info->flags & FBINFO_MISC_TILEBLITTING))
		fbcon_set_tileops(vc, info, p, ops);
	else
		fbcon_set_bitops(ops);
}