platinumfb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

/*
 *  platinumfb.c -- frame buffer device for the PowerMac 'platinum' display
 *
 *  Copyright (C) 1998 Franz Sirl
 *
 *  Frame buffer structure from:
 *    drivers/video/controlfb.c -- frame buffer device for
 *    Apple 'control' display chip.
 *    Copyright (C) 1998 Dan Jacobowitz
 *
 *  Hardware information from:
 *    platinum.c: Console support for PowerMac "platinum" display adaptor.
 *    Copyright (C) 1996 Paul Mackerras and Mark Abene
 *
 *  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 <asm/io.h>
#include <asm/prom.h>
#include <asm/pgtable.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 "platinumfb.h"

static char fontname[40] __initdata = { 0 };

static int currcon = 0;

static int default_vmode = VMODE_NVRAM;
static int default_cmode = CMODE_NVRAM;

struct fb_par_platinum {
	int	vmode, cmode;
	int	xres, yres;
	int	vxres, vyres;
	int	xoffset, yoffset;
};

struct fb_info_platinum {
	struct fb_info			fb_info;
	struct display			disp;
	struct fb_par_platinum		default_par;
	struct fb_par_platinum		current_par;

	struct {
		__u8 red, green, blue;
	}				palette[256];
	
	volatile struct cmap_regs	*cmap_regs;
	unsigned long			cmap_regs_phys;
	
	volatile struct platinum_regs	*platinum_regs;
	unsigned long			platinum_regs_phys;
	
	__u8				*frame_buffer;
	volatile __u8			*base_frame_buffer;
	unsigned long			frame_buffer_phys;
	
	unsigned long			total_vram;
	int				clktype;
	int				dactype;

	union {
#ifdef FBCON_HAS_CFB16
		u16 cfb16[16];
#endif
#ifdef FBCON_HAS_CFB32
		u32 cfb32[16];
#endif
	} fbcon_cmap;
};

/*
 * Frame buffer device API
 */

static int platinum_get_fix(struct fb_fix_screeninfo *fix, int con,
			    struct fb_info *fb);
static int platinum_get_var(struct fb_var_screeninfo *var, int con,
			    struct fb_info *fb);
static int platinum_set_var(struct fb_var_screeninfo *var, int con,
			    struct fb_info *fb);
static int platinum_get_cmap(struct fb_cmap *cmap, int kspc, int con,
			     struct fb_info *info);
static int platinum_set_cmap(struct fb_cmap *cmap, int kspc, int con,
			     struct fb_info *info);


/*
 * Interface to the low level console driver
 */

static int platinum_switch(int con, struct fb_info *fb);
static int platinum_updatevar(int con, struct fb_info *fb);
static void platinum_blank(int blank, struct fb_info *fb);


/*
 * internal functions
 */

static void platinum_of_init(struct device_node *dp);
static inline int platinum_vram_reqd(const struct fb_info_platinum* info,
					int video_mode,
					int color_mode);
static int read_platinum_sense(struct fb_info_platinum *info);
static void set_platinum_clock(struct fb_info_platinum *info);
static void platinum_set_par(const struct fb_par_platinum *par, struct fb_info_platinum *info);
static int platinum_par_to_var(struct fb_var_screeninfo *var,
			       const struct fb_par_platinum *par,
			       const struct fb_info_platinum *info);
static int platinum_var_to_par(const struct fb_var_screeninfo *var,
			       struct fb_par_platinum *par,
			       const struct fb_info_platinum *info);
static int platinum_encode_fix(struct fb_fix_screeninfo *fix,
			       const struct fb_par_platinum *par,
			       const struct fb_info_platinum *info);
static void platinum_set_dispsw(struct display *disp,
				struct fb_info_platinum *info, int cmode,
				int accel);
static int platinum_getcolreg(u_int regno, u_int *red, u_int *green, u_int *blue,
			      u_int *transp, struct fb_info *fb);
static int platinum_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			      u_int transp, struct fb_info *fb);
static void do_install_cmap(int con, struct fb_info *info);


/*
 * Interface used by the world
 */

int platinum_init(void);
int platinum_setup(char*);

static struct fb_ops platinumfb_ops = {
	owner:		THIS_MODULE,
	fb_get_fix:	platinum_get_fix,
	fb_get_var:	platinum_get_var,
	fb_set_var:	platinum_set_var,
	fb_get_cmap:	platinum_get_cmap,
	fb_set_cmap:	platinum_set_cmap,
};

static int platinum_get_fix(struct fb_fix_screeninfo *fix, int con,
			    struct fb_info *fb)
{
	const struct fb_info_platinum *info = (struct fb_info_platinum *)fb;
	struct fb_par_platinum par;

	if (con == -1)
		par = info->default_par;
	else
		platinum_var_to_par(&fb_display[con].var, &par, info);

	platinum_encode_fix(fix, &par, info);
	return 0;
}

static int platinum_get_var(struct fb_var_screeninfo *var, int con,
			    struct fb_info *fb)
{
	const struct fb_info_platinum *info = (struct fb_info_platinum *)fb;

	if (con == -1)
		platinum_par_to_var(var, &info->default_par, info);
	else
		*var = fb_display[con].var;

	return 0;
}

static void platinum_set_dispsw(struct display *disp,
				struct fb_info_platinum *info, int cmode,
				int accel)
{
	switch(cmode) {
#ifdef FBCON_HAS_CFB8
	    case CMODE_8:
		disp->dispsw = &fbcon_cfb8;
		break;
#endif
#ifdef FBCON_HAS_CFB16
	    case CMODE_16:
		disp->dispsw = &fbcon_cfb16;
		disp->dispsw_data = info->fbcon_cmap.cfb16;
		break;
#endif
#ifdef FBCON_HAS_CFB32
	    case CMODE_32:
		disp->dispsw = &fbcon_cfb32;
		disp->dispsw_data = info->fbcon_cmap.cfb32;
		break;
#endif
	    default:
		disp->dispsw = &fbcon_dummy;
		break;
	}
}

static int platinum_set_var(struct fb_var_screeninfo *var, int con,
			    struct fb_info *fb)
{
	struct fb_info_platinum *info = (struct fb_info_platinum *) fb;
	struct fb_par_platinum par;
	struct display *display;
	int oldxres, oldyres, oldvxres, oldvyres, oldbpp, err;
	int activate = var->activate;
	struct platinum_regvals *init;

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

	if((err = platinum_var_to_par(var, &par, info))) {
		printk(KERN_ERR "platinum_set_var: error calling platinum_var_to_par: %d.\n", err);
		return err;
	}
	
	platinum_par_to_var(var, &par, info);

	if ((activate & FB_ACTIVATE_MASK) != FB_ACTIVATE_NOW) {
		printk(KERN_INFO "platinum_set_var: Not activating.\n");
		return 0;
	}

	init = platinum_reg_init[par.vmode-1];

	oldxres = display->var.xres;
	oldyres = display->var.yres;
	oldvxres = display->var.xres_virtual;
	oldvyres = display->var.yres_virtual;
	oldbpp = display->var.bits_per_pixel;
	display->var = *var;

	if (oldxres != var->xres || oldyres != var->yres ||
	    oldvxres != var->xres_virtual || oldyres != var->yres_virtual ||
	    oldbpp != var->bits_per_pixel) {
	    struct fb_fix_screeninfo fix;

	    platinum_encode_fix(&fix, &par, info);
	    display->screen_base = (char *) info->frame_buffer + init->fb_offset + 0x20;
	    display->visual = fix.visual;
	    display->type = fix.type;
	    display->type_aux = fix.type_aux;
	    display->ypanstep = fix.ypanstep;
	    display->ywrapstep = fix.ywrapstep;
	    display->line_length = fix.line_length;
	    display->can_soft_blank = 1;
	    display->inverse = 0;
	    platinum_set_dispsw(display, info, par.cmode, 0);
	    display->scrollmode = SCROLL_YREDRAW;
	    if (info->fb_info.changevar)
	      (*info->fb_info.changevar)(con);
	}

	if (!info->fb_info.display_fg ||
	    info->fb_info.display_fg->vc_num == con)
		platinum_set_par(&par, info);

	if (oldbpp != var->bits_per_pixel) {
	    if ((err = fb_alloc_cmap(&display->cmap, 0, 0)))
	      return err;
	    do_install_cmap(con, &info->fb_info);
	}

	return 0;
}

static int platinum_get_cmap(struct fb_cmap *cmap, int kspc, int con,
			     struct fb_info *info)
{
	if (!info->display_fg ||
	    info->display_fg->vc_num == con)	/* current console? */
		return fb_get_cmap(cmap, kspc, platinum_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 platinum_set_cmap(struct fb_cmap *cmap, int kspc, int con,
			     struct fb_info *info)
{
	int err;
	struct display *disp;

	if (con >= 0)
		disp = &fb_display[con];
	else
		disp = info->disp;
	if (!disp->cmap.len) {     /* no colormap allocated? */
		int size = disp->var.bits_per_pixel == 16 ? 32 : 256;
		if ((err = fb_alloc_cmap(&disp->cmap, size, 0)))
			return err;
	}

	if (!info->display_fg ||
	    info->display_fg->vc_num == con)	/* current console? */
		return fb_set_cmap(cmap, kspc, platinum_setcolreg, info);
	else
		fb_copy_cmap(cmap, &disp->cmap, kspc ? 0 : 1);
	return 0;
}

static int platinum_switch(int con, struct fb_info *fb)
{
	struct fb_info_platinum *info = (struct fb_info_platinum *) fb;
	struct fb_par_platinum par;

	if (fb_display[currcon].cmap.len)
		fb_get_cmap(&fb_display[currcon].cmap, 1, platinum_getcolreg,
			    fb);
	currcon = con;

	platinum_var_to_par(&fb_display[con].var, &par, info);
	platinum_set_par(&par, info);
	platinum_set_dispsw(&fb_display[con], info, par.cmode, 0);
	do_install_cmap(con, fb);

	return 1;
}

static int platinum_updatevar(int con, struct fb_info *fb)
{
	printk(KERN_ERR "platinum_updatevar is doing nothing yet.\n");
	return 0;
}

static void platinum_blank(int blank,  struct fb_info *fb)
{
/*
 *  Blank the screen if blank_mode != 0, else unblank. If blank == NULL
 *  then the caller blanks by setting the CLUT (Color Look Up Table) to all
 *  black. Return 0 if blanking succeeded, != 0 if un-/blanking failed due
 *  to e.g. a video mode which doesn't support it. Implements VESA suspend
 *  and powerdown modes on hardware that supports disabling hsync/vsync:
 *    blank_mode == 2: suspend vsync
 *    blank_mode == 3: suspend hsync
 *    blank_mode == 4: powerdown
 */
/* [danj] I think there's something fishy about those constants... */
/*
	struct fb_info_platinum *info = (struct fb_info_platinum *) fb;
	int	ctrl;

	ctrl = ld_le32(&info->platinum_regs->ctrl.r) | 0x33;
	if (blank)
		--blank_mode;
	if (blank & VESA_VSYNC_SUSPEND)
		ctrl &= ~3;
	if (blank & VESA_HSYNC_SUSPEND)
		ctrl &= ~0x30;
	out_le32(&info->platinum_regs->ctrl.r, ctrl);
*/
/* TODO: Figure out how the heck to powerdown this thing! */
    return;
}

static int platinum_getcolreg(u_int regno, u_int *red, u_int *green,
			      u_int *blue, u_int *transp, struct fb_info *fb)
{
	struct fb_info_platinum *info = (struct fb_info_platinum *) fb;

	if (regno > 255)
		return 1;

	*red = (info->palette[regno].red<<8) | info->palette[regno].red;
	*green = (info->palette[regno].green<<8) | info->palette[regno].green;
	*blue = (info->palette[regno].blue<<8) | info->palette[regno].blue;
	*transp = 0;
	return 0;
}

static int platinum_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			      u_int transp, struct fb_info *fb)
{
	struct fb_info_platinum *info = (struct fb_info_platinum *) fb;
	volatile struct cmap_regs *cmap_regs = info->cmap_regs;

	if (regno > 255)
		return 1;

	red >>= 8;
	green >>= 8;
	blue >>= 8;

	info->palette[regno].red = red;
	info->palette[regno].green = green;
	info->palette[regno].blue = blue;

	out_8(&cmap_regs->addr, regno);		/* tell clut what addr to fill	*/
	out_8(&cmap_regs->lut, red);		/* send one color channel at	*/
	out_8(&cmap_regs->lut, green);		/* a time...			*/
	out_8(&cmap_regs->lut, blue);

	if(regno < 16) {
#ifdef FBCON_HAS_CFB16
		info->fbcon_cmap.cfb16[regno] = (regno << 10) | (regno << 5) | (regno << 0);
#endif
#ifdef FBCON_HAS_CFB32
		info->fbcon_cmap.cfb32[regno] = (regno << 24) | (regno << 16) | (regno << 8) | regno;
#endif
	}
	return 0;
}

static void do_install_cmap(int con, struct fb_info *info)
{
	if (con != currcon)
		return;
	if (fb_display[con].cmap.len)
		fb_set_cmap(&fb_display[con].cmap, 1, platinum_setcolreg,
			    info);
	else {
		int size = fb_display[con].var.bits_per_pixel == 16 ? 32 : 256;
		fb_set_cmap(fb_default_cmap(size), 1, platinum_setcolreg,
			    info);
	}
}