controlfb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

/*
 *  controlfb.c -- frame buffer device for the PowerMac 'control' display
 *
 *  Created 12 July 1998 by Dan Jacobowitz <[e-mail]>
 *  Copyright (C) 1998 Dan Jacobowitz
 *  Copyright (C) 2001 Takashi Oe
 *
 *  Mmap code by Michel Lanners <[e-mail]>
 *
 *  Frame buffer structure from:
 *    drivers/video/chipsfb.c -- frame buffer device for
 *    Chips & Technologies 65550 chip.
 *
 *    Copyright (C) 1998 Paul Mackerras
 *
 *    This file is derived from the Powermac "chips" driver:
 *    Copyright (C) 1997 Fabio Riccardi.
 *    And from the frame buffer device for Open Firmware-initialized devices:
 *    Copyright (C) 1997 Geert Uytterhoeven.
 *
 *  Hardware information from:
 *    control.c: Console support for PowerMac "control" display adaptor.
 *    Copyright (C) 1996 Paul Mackerras
 *
 *  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.
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/selection.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/nvram.h>
#ifdef CONFIG_FB_COMPAT_XPMAC
#include <asm/vc_ioctl.h>
#endif
#include <linux/adb.h>
#include <linux/cuda.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pgtable.h>
#include <asm/btext.h>

#include <video/fbcon.h>
#include <video/fbcon-cfb8.h>
#include <video/fbcon-cfb16.h>
#include <video/fbcon-cfb32.h>
#include <video/macmodes.h>

#include "controlfb.h"

struct fb_par_control {
	int	vmode, cmode;
	int	xres, yres;
	int	vxres, vyres;
	int	xoffset, yoffset;
	int	pitch;
	struct control_regvals	regvals;
	unsigned long sync;
	unsigned char ctrl;
};

#define DIRTY(z) ((x)->z != (y)->z)
#define DIRTY_CMAP(z) (memcmp(&((x)->z), &((y)->z), sizeof((y)->z)))
static inline int PAR_EQUAL(struct fb_par_control *x, struct fb_par_control *y)
{
	int i, results;

	results = 1;
	for (i = 0; i < 3; i++)
		results &= !DIRTY(regvals.clock_params[i]);
	if (!results)
		return 0;
	for (i = 0; i < 16; i++)
		results &= !DIRTY(regvals.regs[i]);
	if (!results)
		return 0;
	return (!DIRTY(cmode) && !DIRTY(xres) && !DIRTY(yres)
		&& !DIRTY(vxres) && !DIRTY(vyres));
}
static inline int VAR_MATCH(struct fb_var_screeninfo *x, struct fb_var_screeninfo *y)
{
	return (!DIRTY(bits_per_pixel) && !DIRTY(xres)
		&& !DIRTY(yres) && !DIRTY(xres_virtual)
		&& !DIRTY(yres_virtual)
		&& !DIRTY_CMAP(red) && !DIRTY_CMAP(green) && !DIRTY_CMAP(blue));
}

struct fb_info_control {
	struct fb_info			info;
	struct display			display;
	struct fb_par_control		par;
	struct {
		__u8 red, green, blue;
	}			palette[256];
	
	struct cmap_regs	*cmap_regs;
	unsigned long		cmap_regs_phys;
	
	struct control_regs	*control_regs;
	unsigned long		control_regs_phys;
	unsigned long		control_regs_size;
	
	__u8			*frame_buffer;
	unsigned long		frame_buffer_phys;
	unsigned long		fb_orig_base;
	unsigned long		fb_orig_size;

	int			control_use_bank2;
	unsigned long		total_vram;
	unsigned char		vram_attr;
	union {
#ifdef FBCON_HAS_CFB16
		u16 cfb16[16];
#endif
#ifdef FBCON_HAS_CFB32
		u32 cfb32[16];
#endif
	} fbcon_cmap;
};

/* control register access macro */
#define CNTRL_REG(INFO,REG) (&(((INFO)->control_regs->REG).r))


/******************** Prototypes for exported functions ********************/
/*
 * struct fb_ops
 */
static int control_get_fix(struct fb_fix_screeninfo *fix, int con,
	struct fb_info *info);
static int control_get_var(struct fb_var_screeninfo *var, int con,
	struct fb_info *info);
static int control_set_var(struct fb_var_screeninfo *var, int con,
	struct fb_info *info);
static int control_pan_display(struct fb_var_screeninfo *var, int con,
	struct fb_info *info);
static int control_get_cmap(struct fb_cmap *cmap, int kspc, int con,
	struct fb_info *info);
static int control_set_cmap(struct fb_cmap *cmap, int kspc, int con,
	struct fb_info *info);
static int control_mmap(struct fb_info *info, struct file *file,
	struct vm_area_struct *vma);

/*
 * low level fbcon ops
 */
static int controlfb_switch(int con, struct fb_info *info);
static int controlfb_updatevar(int con, struct fb_info *info);
static void controlfb_blank(int blank_mode, struct fb_info *info);

/*
 * low level cmap set/get ops
 */
static int controlfb_getcolreg(u_int regno, u_int *red, u_int *green,
	u_int *blue, u_int *transp, struct fb_info *info);
static int controlfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
	u_int transp, struct fb_info *info);

/*
 * inititialization
 */
int control_init(void);
void control_setup(char *);

/*
 * low level fbcon revc ops
 */
static void control_cfb16_revc(struct display *p, int xx, int yy);
static void control_cfb32_revc(struct display *p, int xx, int yy);


/******************** Prototypes for internal functions **********************/

static void do_install_cmap(struct display *disp, struct fb_info *info);
static void set_control_clock(unsigned char *params);
static int init_control(struct fb_info_control *p);
static void control_set_hardware(struct fb_info_control *p,
	struct fb_par_control *par);
static int control_of_init(struct device_node *dp);
static void control_par_to_fix(struct fb_par_control *par,
	struct fb_fix_screeninfo *fix, struct fb_info_control *p);
static void control_set_dispsw(struct display *disp, int cmode,
	struct fb_info_control *p);
static void find_vram_size(struct fb_info_control *p);
static int read_control_sense(struct fb_info_control *p);
static int calc_clock_params(unsigned long clk, unsigned char *param);
static int control_var_to_par(struct fb_var_screeninfo *var,
	struct fb_par_control *par, const struct fb_info *fb_info);
static inline void control_par_to_var(struct fb_par_control *par,
	struct fb_var_screeninfo *var);
static void control_par_to_fix(struct fb_par_control *par,
	struct fb_fix_screeninfo *fix, struct fb_info_control *p);
static void control_par_to_display(struct fb_par_control *par,
	struct display *disp, struct fb_fix_screeninfo *fix,
	struct fb_info_control *p);
static void control_set_dispsw(struct display *disp, int cmode,
	struct fb_info_control *p);
static void control_init_info(struct fb_info *info, struct fb_info_control *p);
static void control_cleanup(void);


/************************** Internal variables *******************************/

static int currcon;
static struct fb_info_control *control_fb;

static char fontname[40] __initdata = { 0 };
static int default_vmode __initdata = VMODE_NVRAM;
static int default_cmode __initdata = CMODE_NVRAM;


static struct fb_ops controlfb_ops = {
	owner:		THIS_MODULE,
	fb_get_fix:	control_get_fix,
	fb_get_var:	control_get_var,
	fb_set_var:	control_set_var,
	fb_get_cmap:	control_get_cmap,
	fb_set_cmap:	control_set_cmap,
	fb_pan_display:	control_pan_display,
	fb_mmap:	control_mmap,
};


/********************  The functions for controlfb_ops ********************/

#ifdef MODULE
MODULE_LICENSE("GPL");

int init_module(void)
{
	struct device_node *dp;

	dp = find_devices("control");
	if (dp != 0 && !control_of_init(dp))
		return 0;

	return -ENXIO;
}

void cleanup_module(void)
{
	control_cleanup();
}
#endif

/*********** Providing our information to the user ************/

static int control_get_fix(struct fb_fix_screeninfo *fix, int con,
			 struct fb_info *info)
{
	struct fb_info_control *p = (struct fb_info_control *) info;

	if(con == -1) {
		control_par_to_fix(&p->par, fix, p);
	} else {
		struct fb_par_control par;
		
		control_var_to_par(&fb_display[con].var, &par, info);
		control_par_to_fix(&par, fix, p);
	}
	return 0;
}

static int control_get_var(struct fb_var_screeninfo *var, int con,
			 struct fb_info *info)
{
	struct fb_info_control *p = (struct fb_info_control *) info;

	if(con == -1) {
		control_par_to_var(&p->par, var);
	} else {
		*var = fb_display[con].var;
	}
	return 0;
}


/*
 * Sets everything according to var
 */
static int control_set_var(struct fb_var_screeninfo *var, int con,
			 struct fb_info *info)
{
	struct fb_info_control *p = (struct fb_info_control *) info;
	struct display *disp;
	struct fb_par_control par;
	int depthchange, err;
	int activate = var->activate;

	if((err = control_var_to_par(var, &par, info))) {
		if (con < 0)
			printk (KERN_ERR "control_set_var: error calling"
					 " control_var_to_par: %d.\n", err);
		return err;
	}
	
	control_par_to_var(&par, var);
	
	if ((activate & FB_ACTIVATE_MASK) != FB_ACTIVATE_NOW)
		return 0;

	disp = (con >= 0) ? &fb_display[con] : info->disp;

	depthchange = (disp->var.bits_per_pixel != var->bits_per_pixel);
	if(!VAR_MATCH(&disp->var, var)) {
		struct fb_fix_screeninfo	fix;
		control_par_to_fix(&par, &fix, p);
		control_par_to_display(&par, disp, &fix, p);
		if(info->changevar)
			(*info->changevar)(con);
	} else
		disp->var = *var;

	if(con == currcon) {
		control_set_hardware(p, &par);
		if(depthchange) {
			if((err = fb_alloc_cmap(&disp->cmap, 0, 0)))
				return err;
			do_install_cmap(disp, info);
		}
	}

	return 0;
}


/*
 * Set screen start address according to var offset values
 */
static inline void set_screen_start(int xoffset, int yoffset,
	struct fb_info_control *p)
{
	struct fb_par_control *par = &p->par;

	par->xoffset = xoffset;
	par->yoffset = yoffset;
	out_le32(CNTRL_REG(p,start_addr),
		 par->yoffset * par->pitch + (par->xoffset << par->cmode));
}


static int control_pan_display(struct fb_var_screeninfo *var, int con,
			     struct fb_info *info)
{
	unsigned int xoffset, hstep;
	struct fb_info_control *p = (struct fb_info_control *)info;
	struct fb_par_control *par = &p->par;

	/*
	 * make sure start addr will be 32-byte aligned
	 */
	hstep = 0x1f >> par->cmode;
	xoffset = (var->xoffset + hstep) & ~hstep;

	if (xoffset+par->xres > par->vxres ||
	    var->yoffset+par->yres > par->vyres)
		return -EINVAL;

	set_screen_start(xoffset, var->yoffset, p);

	return 0;
}

static int control_get_cmap(struct fb_cmap *cmap, int kspc, int con,
			  struct fb_info *info)
{
	if (con == currcon)		/* current console? */
		return fb_get_cmap(cmap, kspc, controlfb_getcolreg, info);
	if (fb_display[con].cmap.len)	/* non default colormap? */
		fb_copy_cmap(&fb_display[con].cmap, cmap, kspc ? 0: 2);
	else {
		int size = fb_display[con].var.bits_per_pixel == 16 ? 32 : 256;
		fb_copy_cmap(fb_default_cmap(size), cmap, kspc ? 0 : 2);
	}
	return 0;
}

static int control_set_cmap(struct fb_cmap *cmap, int kspc, int con,
			 struct fb_info *info)
{
	struct display *disp = (con < 0)? info->disp: &fb_display[con];
	int err, size = disp->var.bits_per_pixel == 16 ? 32 : 256;

	if (disp->cmap.len != size) {
		err = fb_alloc_cmap(&disp->cmap, size, 0);
		if (err)
			return err;
	}
	if (con == currcon)
		return fb_set_cmap(cmap, kspc, controlfb_setcolreg, info);
	fb_copy_cmap(cmap, &disp->cmap, kspc ? 0 : 1);
	return 0;
}


/*
 * Private mmap since we want to have a different caching on the framebuffer
 * for controlfb.
 * Note there's no locking in here; it's done in fb_mmap() in fbmem.c.
 */
static int control_mmap(struct fb_info *info, struct file *file,
                       struct vm_area_struct *vma)
{
       struct fb_ops *fb = info->fbops;
       struct fb_fix_screeninfo fix;
       struct fb_var_screeninfo var;
       unsigned long off, start;
       u32 len;

       fb->fb_get_fix(&fix, PROC_CONSOLE(info), info);
       off = vma->vm_pgoff << PAGE_SHIFT;

       /* frame buffer memory */
       start = fix.smem_start;
       len = PAGE_ALIGN((start & ~PAGE_MASK)+fix.smem_len);
       if (off >= len) {
               /* memory mapped io */
               off -= len;
               fb->fb_get_var(&var, PROC_CONSOLE(info), info);
               if (var.accel_flags)
                       return -EINVAL;
               start = fix.mmio_start;
               len = PAGE_ALIGN((start & ~PAGE_MASK)+fix.mmio_len);
               pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE|_PAGE_GUARDED;
       } else {
               /* framebuffer */
               pgprot_val(vma->vm_page_prot) |= _PAGE_WRITETHRU;
       }
       start &= PAGE_MASK;
       if ((vma->vm_end - vma->vm_start + off) > len)
       		return -EINVAL;
       off += start;
       vma->vm_pgoff = off >> PAGE_SHIFT;
       if (io_remap_page_range(vma->vm_start, off,
           vma->vm_end - vma->vm_start, vma->vm_page_prot))
               return -EAGAIN;

       return 0;
}


/********************  End of controlfb_ops implementation  ******************/

/*
 * low level fbcon ops
 */

static int controlfb_switch(int con, struct fb_info *info)
{
	struct fb_info_control	*p = (struct fb_info_control *)info;
	struct fb_par_control	par;

	if (currcon >= 0 && fb_display[currcon].cmap.len)
		fb_get_cmap(&fb_display[currcon].cmap, 1, controlfb_getcolreg,
			    info);
	currcon = con;

	fb_display[con].var.activate = FB_ACTIVATE_NOW;
	control_var_to_par(&fb_display[con].var, &par, info);
	control_set_hardware(p, &par);
	control_set_dispsw(&fb_display[con], par.cmode, p);
	do_install_cmap(&fb_display[con], info);

	return 1;
}


static int controlfb_updatevar(int con, struct fb_info *info)
{
	struct fb_var_screeninfo *var = &fb_display[con].var;
	struct fb_info_control *p = (struct fb_info_control *) info;

	set_screen_start(var->xoffset, var->yoffset, p);

	return 0;