/* $Id: g364fb.c,v 1.3 1998/08/28 22:43:00 tsbogend Exp $
   *
   * linux/drivers/video/g364fb.c -- Mips Magnum frame buffer device
   *
   * (C) 1998 Thomas Bogendoerfer
   *
   *  This driver is based on tgafb.c
   *
   *	Copyright (C) 1997 Geert Uytterhoeven 
   *	Copyright (C) 1995  Jay Estabrook
   *
   *  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/module.h>
  #include <linux/console.h>
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/string.h>
  #include <linux/mm.h>
  #include <linux/vmalloc.h>
  #include <linux/delay.h>
  #include <linux/interrupt.h>
  #include <linux/fb.h>
  #include <linux/init.h>
  #include <asm/io.h>
  #include <asm/jazz.h>
  
  /* 
   * Various defines for the G364
   */
  #define G364_MEM_BASE   0xe4400000
  #define G364_PORT_BASE  0xe4000000
  #define ID_REG 		0xe4000000	/* Read only */
  #define BOOT_REG 	0xe4080000
  #define TIMING_REG 	0xe4080108	/* to 0x080170 - DON'T TOUCH! */
  #define DISPLAY_REG 	0xe4080118
  #define VDISPLAY_REG 	0xe4080150
  #define MASK_REG 	0xe4080200
  #define CTLA_REG 	0xe4080300
  #define CURS_TOGGLE 	0x800000
  #define BIT_PER_PIX	0x700000	/* bits 22 to 20 of Control A */
  #define DELAY_SAMPLE    0x080000
  #define PORT_INTER	0x040000
  #define PIX_PIPE_DEL	0x030000	/* bits 17 and 16 of Control A */
  #define PIX_PIPE_DEL2	0x008000	/* same as above - don't ask me why */
  #define TR_CYCLE_TOG	0x004000
  #define VRAM_ADR_INC	0x003000	/* bits 13 and 12 of Control A */
  #define BLANK_OFF	0x000800
  #define FORCE_BLANK	0x000400
  #define BLK_FUN_SWTCH	0x000200
  #define BLANK_IO	0x000100
  #define BLANK_LEVEL	0x000080
  #define A_VID_FORM	0x000040
  #define D_SYNC_FORM	0x000020
  #define FRAME_FLY_PAT	0x000010
  #define OP_MODE		0x000008
  #define INTL_STAND	0x000004
  #define SCRN_FORM	0x000002
  #define ENABLE_VTG	0x000001
  #define TOP_REG 	0xe4080400
  #define CURS_PAL_REG 	0xe4080508	/* to 0x080518 */
  #define CHKSUM_REG 	0xe4080600	/* to 0x080610 - unused */
  #define CURS_POS_REG 	0xe4080638
  #define CLR_PAL_REG 	0xe4080800	/* to 0x080ff8 */
  #define CURS_PAT_REG 	0xe4081000	/* to 0x081ff8 */
  #define MON_ID_REG 	0xe4100000	/* unused */
  #define RESET_REG 	0xe4180000	/* Write only */
  
  static struct fb_info fb_info;
  
  static struct fb_fix_screeninfo fb_fix __initdata = {
  	.id 		= "G364 8plane",
  	.smem_start 	= 0x40000000,	/* physical address */
  	.type 		= FB_TYPE_PACKED_PIXELS,
  	.visual 	= FB_VISUAL_PSEUDOCOLOR,
  	.ypanstep 	= 1,
  	.accel 		= FB_ACCEL_NONE,
  };
  
  static struct fb_var_screeninfo fb_var __initdata = {
  	.bits_per_pixel = 8,
  	.red 		= { 0, 8, 0 },
        	.green 		= { 0, 8, 0 },
        	.blue		= { 0, 8, 0 },
        	.activate	= FB_ACTIVATE_NOW,
        	.height		= -1,
        	.width		= -1,
        	.pixclock	= 39722,
        	.left_margin	= 40,
        	.right_margin	= 24,
        	.upper_margin	= 32,
        	.lower_margin	= 11,
        	.hsync_len 	= 96,
        	.vsync_len 	= 2,
        	.vmode		= FB_VMODE_NONINTERLACED,
  };
  
  /*
   *  Interface used by the world
   */
  int g364fb_init(void);
  
  static int g364fb_pan_display(struct fb_var_screeninfo *var,
  			      struct fb_info *info);
  static int g364fb_setcolreg(u_int regno, u_int red, u_int green,
  			    u_int blue, u_int transp,
  			    struct fb_info *info);
  static int g364fb_cursor(struct fb_info *info, struct fb_cursor *cursor);
  static int g364fb_blank(int blank, struct fb_info *info);
  
  static struct fb_ops g364fb_ops = {
  	.owner		= THIS_MODULE,
  	.fb_setcolreg	= g364fb_setcolreg,
  	.fb_pan_display	= g364fb_pan_display,
  	.fb_blank	= g364fb_blank,
  	.fb_fillrect	= cfb_fillrect,
  	.fb_copyarea	= cfb_copyarea,
  	.fb_imageblit	= cfb_imageblit,
  	.fb_cursor	= g364fb_cursor,
  };
  
  int g364fb_cursor(struct fb_info *info, struct fb_cursor *cursor)
  {
  	
  	switch (cursor->enable) {
  	case CM_ERASE:
  		*(unsigned int *) CTLA_REG |= CURS_TOGGLE;
  		break;
  
  	case CM_MOVE:
  	case CM_DRAW:
  		*(unsigned int *) CTLA_REG &= ~CURS_TOGGLE;
  		*(unsigned int *) CURS_POS_REG =
  		    ((x * fontwidth(p)) << 12) | ((y * fontheight(p)) -
  						  info->var.yoffset);
  		break;
  	}
  	return 0;
  }
  
  /*
   *  Pan or Wrap the Display
   *
   *  This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
   */
  static int g364fb_pan_display(struct fb_var_screeninfo *var, 
  			      struct fb_info *info)
  {
  	if (var->xoffset ||
  	    var->yoffset + info->var.yres > info->var.yres_virtual)
  		return -EINVAL;
  
  	*(unsigned int *) TOP_REG = var->yoffset * info->var.xres;
  	return 0;
  }
  
  /*
   *  Blank the display.
   */
  static int g364fb_blank(int blank, struct fb_info *info)
  {
  	if (blank)
  		*(unsigned int *) CTLA_REG |= FORCE_BLANK;
  	else
  		*(unsigned int *) CTLA_REG &= ~FORCE_BLANK;
  	return 0;
  }
  
  /*
   *  Set a single color register. Return != 0 for invalid regno.
   */
  static int g364fb_setcolreg(u_int regno, u_int red, u_int green,
  			    u_int blue, u_int transp, struct fb_info *info)
  {
  	volatile unsigned int *ptr = (volatile unsigned int *) CLR_PAL_REG;
  
  	if (regno > 255)
  		return 1;
  
  	red >>= 8;
  	green >>= 8;
  	blue >>= 8;
  
  	ptr[regno << 1] = (red << 16) | (green << 8) | blue;
  
  	return 0;
  }
  
  /*
   *  Initialisation
   */
  int __init g364fb_init(void)
  {
  	volatile unsigned int *pal_ptr =
  	    (volatile unsigned int *) CLR_PAL_REG;
  	volatile unsigned int *curs_pal_ptr =
  	    (volatile unsigned int *) CURS_PAL_REG;
  	int mem, i, j;
  
  	if (fb_get_options("g364fb", NULL))
  		return -ENODEV;
  
  	/* TBD: G364 detection */
  
  	/* get the resolution set by ARC console */
  	*(volatile unsigned int *) CTLA_REG &= ~ENABLE_VTG;
  	fb_var.xres =
  	    (*((volatile unsigned int *) DISPLAY_REG) & 0x00ffffff) * 4;
  	fb_var.yres =
  	    (*((volatile unsigned int *) VDISPLAY_REG) & 0x00ffffff) / 2;
  	*(volatile unsigned int *) CTLA_REG |= ENABLE_VTG;
  
  	/* setup cursor */
  	curs_pal_ptr[0] |= 0x00ffffff;
  	curs_pal_ptr[2] |= 0x00ffffff;
  	curs_pal_ptr[4] |= 0x00ffffff;
  
  	/*
  	 * first set the whole cursor to transparent
  	 */
  	for (i = 0; i < 512; i++)
  		*(unsigned short *) (CURS_PAT_REG + i * 8) = 0;
  
  	/*
  	 * switch the last two lines to cursor palette 3
  	 * we assume here, that FONTSIZE_X is 8
  	 */
  	*(unsigned short *) (CURS_PAT_REG + 14 * 64) = 0xffff;
  	*(unsigned short *) (CURS_PAT_REG + 15 * 64) = 0xffff;
  	fb_var.xres_virtual = fbvar.xres;
  	fb_fix.line_length = (xres / 8) * fb_var.bits_per_pixel;
  	fb_fix.smem_start = 0x40000000;	/* physical address */
  	/* get size of video memory; this is special for the JAZZ hardware */
  	mem = (r4030_read_reg32(JAZZ_R4030_CONFIG) >> 8) & 3;
  	fb_fix.smem_len = (1 << (mem * 2)) * 512 * 1024;
  	fb_var.yres_virtual = fb_fix.smem_len / fb_var.xres;
  
  	fb_info.fbops = &g364fb_ops;
  	fb_info.screen_base = (char *) G364_MEM_BASE;	/* virtual kernel address */
  	fb_info.var = fb_var;
  	fb_info.fix = fb_fix;
  	fb_info.flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
  
  	fb_alloc_cmap(&fb_info.cmap, 255, 0);
  
  	if (register_framebuffer(&fb_info) < 0)
  		return -EINVAL;
  	return 0;
  }
  
  module_init(g364fb_init);
  MODULE_LICENSE("GPL");