fbcon.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

/*
 *  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/smp.h>
#include <linux/init.h>
#include <linux/pm.h>

#include <asm/irq.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#ifdef CONFIG_AMIGA
#include <asm/amigahw.h>
#include <asm/amigaints.h>
#endif /* CONFIG_AMIGA */
#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
#ifdef CONFIG_FBCON_VGA_PLANES
#include <asm/io.h>
#endif
#define INCLUDE_LINUX_LOGO_DATA
/* 
 * The #include <asm/linux_logo.h> didn't seem to work for us.
 * so I use #include <linux/linux_logo.h> if compiling for
 * our board
 * (20030314 - hede) 
 */
#if defined(CONFIG_FB_COBRA5272) || defined (CONFIG_DRAGEN2)
#include <linux/linux_logo.h>
#else
#include <asm/linux_logo.h>
#endif

#include <video/fbcon.h>
#include <video/fbcon-mac.h>	/* for 6x11 font on mac */
#include <video/font.h>

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

#define LOGO_H			80
#define LOGO_W			80
#define LOGO_LINE	(LOGO_W/8)

struct display fb_display[MAX_NR_CONSOLES];
char con2fb_map[MAX_NR_CONSOLES];
static int logo_lines;
static int logo_shown = -1;
/* 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;

#define REFCOUNT(fd)	(((int *)(fd))[-1])
#define FNTSIZE(fd)	(((int *)(fd))[-2])
#define FNTCHARCNT(fd)	(((int *)(fd))[-3])
#define FNTSUM(fd)	(((int *)(fd))[-4])
#define FONT_EXTRA_WORDS 4

#define CM_SOFTBACK	(8)

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

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

#ifdef CONFIG_PM
static int pm_fbcon_request(struct pm_dev *dev, pm_request_t rqst, void *data);
static struct pm_dev *pm_fbcon;
static int fbcon_sleeping;
#endif

/*
 * Emmanuel: fbcon will now use a hardware cursor if the
 * low-level driver provides a non-NULL dispsw->cursor pointer,
 * in which case the hardware should do blinking, etc.
 *
 * if dispsw->cursor is NULL, use Atari alike software cursor
 */

static int cursor_drawn;

#define CURSOR_DRAW_DELAY		(1)

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

static int vbl_cursor_cnt;
static int cursor_on;
static int cursor_blink_rate;

static inline void cursor_undrawn(void)
{
    vbl_cursor_cnt = 0;
    cursor_drawn = 0;
}


#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 *conp, int init);
static void fbcon_deinit(struct vc_data *conp);
static int fbcon_changevar(int con);
static void fbcon_clear(struct vc_data *conp, int sy, int sx, int height,
		       int width);
static void fbcon_putc(struct vc_data *conp, int c, int ypos, int xpos);
static void fbcon_putcs(struct vc_data *conp, const unsigned short *s, int count,
			int ypos, int xpos);
static void fbcon_cursor(struct vc_data *conp, int mode);
static int fbcon_scroll(struct vc_data *conp, int t, int b, int dir,
			 int count);
static void fbcon_bmove(struct vc_data *conp, int sy, int sx, int dy, int dx,
			int height, int width);
static int fbcon_switch(struct vc_data *conp);
static int fbcon_blank(struct vc_data *conp, int blank);
static int fbcon_font_op(struct vc_data *conp, struct console_font_op *op);
static int fbcon_set_palette(struct vc_data *conp, unsigned char *table);
static int fbcon_scrolldelta(struct vc_data *conp, int lines);


/*
 *  Internal routines
 */

static void fbcon_setup(int con, int init, int logo);
static __inline__ int real_y(struct display *p, int ypos);
static void fbcon_vbl_handler(int irq, void *dummy, struct pt_regs *fp);
static __inline__ void updatescrollmode(struct display *p);
static __inline__ void ywrap_up(int unit, struct vc_data *conp,
				struct display *p, int count);
static __inline__ void ywrap_down(int unit, struct vc_data *conp,
				  struct display *p, int count);
static __inline__ void ypan_up(int unit, struct vc_data *conp,
			       struct display *p, int count);
static __inline__ void ypan_down(int unit, struct vc_data *conp,
				 struct display *p, int count);
static void fbcon_bmove_rec(struct display *p, int sy, int sx, int dy, int dx,
			    int height, int width, u_int y_break);

static int fbcon_show_logo(void);

#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 void fbcon_vbl_detect(int irq, void *dummy, struct pt_regs *fp)
{
      vbl_detected++;
}
#endif

static void cursor_timer_handler(unsigned long dev_addr);

static struct timer_list cursor_timer = {
    function: cursor_timer_handler
};
static int use_timer_cursor;

static void cursor_timer_handler(unsigned long dev_addr)
{
      fbcon_vbl_handler(0, NULL, NULL);
      cursor_timer.expires = jiffies+HZ/50;
      add_timer(&cursor_timer);
}


/**
 *	PROC_CONSOLE - find the attached tty or visible console
 *	@info: frame buffer info structure
 *
 *	Finds the tty attached to the process or visible console if
 *	the process is not directly attached to a tty (e.g. remote
 *	user) for device @info.
 *
 *	Returns -1 errno on error, or tty/visible console number
 *	on success.
 *
 */

int PROC_CONSOLE(const struct fb_info *info)
{
        int fgc;

	if (info->display_fg == NULL)
		return -1;

        if (!current->tty ||
	    current->tty->driver.type != TTY_DRIVER_TYPE_CONSOLE ||
	    MINOR(current->tty->device) < 1)
		fgc = info->display_fg->vc_num;
	else
		fgc = MINOR(current->tty->device)-1;

	/* Does this virtual console belong to the specified fbdev? */
	if (fb_display[fgc].fb_info != info)
		return -1;

	return fgc;
}


/**
 *	set_all_vcs - set all virtual consoles to match
 *	@fbidx: frame buffer index (e.g. fb0, fb1, ...)
 *	@fb: frame buffer ops structure
 *	@var: frame buffer screen structure to set
 *	@info: frame buffer info structure
 *
 *	Set all virtual consoles to match screen info set in @var
 *	for device @info.
 *
 *	Returns negative errno on error, or zero on success.
 *
 */

int set_all_vcs(int fbidx, struct fb_ops *fb, struct fb_var_screeninfo *var,
                struct fb_info *info)
{
    int unit, err;

    var->activate |= FB_ACTIVATE_TEST;
    err = fb->fb_set_var(var, PROC_CONSOLE(info), info);
    var->activate &= ~FB_ACTIVATE_TEST;
    if (err)
            return err;
    for (unit = 0; unit < MAX_NR_CONSOLES; unit++)
            if (fb_display[unit].conp && con2fb_map[unit] == fbidx)
                    fb->fb_set_var(var, unit, info);
    return 0;
}


/**
 *	set_con2fb_map - map console to frame buffer device
 *	@unit: virtual console number to map
 *	@newidx: frame buffer index to map virtual console to
 *
 *	Maps a virtual console @unit to a frame buffer device
 *	@newidx.
 *
 */

void set_con2fb_map(int unit, int newidx)
{
    int oldidx = con2fb_map[unit];
    struct fb_info *oldfb, *newfb;
    struct vc_data *conp;
    char *fontdata;
    unsigned short fontwidth, fontheight, fontwidthlog, fontheightlog;
    int userfont;

    if (newidx != con2fb_map[unit]) {
       oldfb = registered_fb[oldidx];
       newfb = registered_fb[newidx];
	if (newfb->fbops->owner)
		__MOD_INC_USE_COUNT(newfb->fbops->owner);
	if (newfb->fbops->fb_open && newfb->fbops->fb_open(newfb,0)) {
		if (newfb->fbops->owner)
			__MOD_DEC_USE_COUNT(newfb->fbops->owner);
		return;
	}
	if (oldfb->fbops->fb_release)
		oldfb->fbops->fb_release(oldfb,0);
	if (oldfb->fbops->owner)
		__MOD_DEC_USE_COUNT(oldfb->fbops->owner);
       conp = fb_display[unit].conp;
       fontdata = fb_display[unit].fontdata;
       fontwidth = fb_display[unit]._fontwidth;
       fontheight = fb_display[unit]._fontheight;
       fontwidthlog = fb_display[unit]._fontwidthlog;
       fontheightlog = fb_display[unit]._fontheightlog;
       userfont = fb_display[unit].userfont;
       con2fb_map[unit] = newidx;
       fb_display[unit] = *(newfb->disp);
       fb_display[unit].conp = conp;
       fb_display[unit].fontdata = fontdata;
       fb_display[unit]._fontwidth = fontwidth;
       fb_display[unit]._fontheight = fontheight;
       fb_display[unit]._fontwidthlog = fontwidthlog;
       fb_display[unit]._fontheightlog = fontheightlog;
       fb_display[unit].userfont = userfont;
       fb_display[unit].fb_info = newfb;
       if (conp)
	   conp->vc_display_fg = &newfb->display_fg;
       if (!newfb->display_fg)
	   newfb->display_fg = conp;
       if (!newfb->changevar)
           newfb->changevar = oldfb->changevar;
       /* tell console var has changed */
       if (newfb->changevar)
           newfb->changevar(unit);
   }
}

/*
 *  Low Level Operations
 */

struct display_switch fbcon_dummy;

/* NOTE: fbcon cannot be __init: it may be called from take_over_console later */

static const char *fbcon_startup(void)
{
    const char *display_desc = "frame buffer device";
    int irqres = 1;
    static int done = 0;

    /*
     *  If num_registered_fb is zero, this is a call for the dummy part.
     *  The frame buffer devices weren't initialized yet.
     */
    if (!num_registered_fb || done)
	return display_desc;
    done = 1;

#ifdef CONFIG_AMIGA
    if (MACH_IS_AMIGA) {
	cursor_blink_rate = AMIGA_CURSOR_BLINK_RATE;
	irqres = request_irq(IRQ_AMIGA_VERTB, fbcon_vbl_handler, 0,
			     "console/cursor", fbcon_vbl_handler);
    }
#endif /* CONFIG_AMIGA */
#ifdef CONFIG_ATARI
    if (MACH_IS_ATARI) {
	cursor_blink_rate = ATARI_CURSOR_BLINK_RATE;
	irqres = request_irq(IRQ_AUTO_4, fbcon_vbl_handler, IRQ_TYPE_PRIO,
			     "console/cursor", fbcon_vbl_handler);
    }
#endif /* CONFIG_ATARI */

#ifdef CONFIG_MAC
    /*
     * On a Macintoy, the VBL interrupt may or may not be active. 
     * As interrupt based cursor is more reliable and race free, we 
     * probe for VBL interrupts.
     */
    if (MACH_IS_MAC) {
	int ct = 0;
	/*
	 * Probe for VBL: set temp. handler ...
	 */
	irqres = request_irq(IRQ_MAC_VBL, fbcon_vbl_detect, 0,
			     "console/cursor", fbcon_vbl_detect);
	vbl_detected = 0;

	/*
	 * ... and spin for 20 ms ...
	 */
	while (!vbl_detected && ++ct<1000)
	    udelay(20);
 
	if(ct==1000)
	    printk("fbcon_startup: No VBL detected, using timer based cursor.\n");
 
	free_irq(IRQ_MAC_VBL, fbcon_vbl_detect);

	if (vbl_detected) {
	    /*
	     * interrupt based cursor ok
	     */
	    cursor_blink_rate = MAC_CURSOR_BLINK_RATE;
	    irqres = request_irq(IRQ_MAC_VBL, fbcon_vbl_handler, 0,
				 "console/cursor", fbcon_vbl_handler);
	} else {
	    /*
	     * VBL not detected: fall through, use timer based cursor
	     */
	    irqres = 1;
	}