atafb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

/*
 * linux/drivers/video/atafb.c -- Atari builtin chipset frame buffer device
 *
 *  Copyright (C) 1994 Martin Schaller & Roman Hodek
 *  
 * 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.
 *
 * History:
 *   - 03 Jan 95: Original version by Martin Schaller: The TT driver and
 *                all the device independent stuff
 *   - 09 Jan 95: Roman: I've added the hardware abstraction (hw_switch)
 *                and wrote the Falcon, ST(E), and External drivers
 *                based on the original TT driver.
 *   - 07 May 95: Martin: Added colormap operations for the external driver
 *   - 21 May 95: Martin: Added support for overscan
 *		  Andreas: some bug fixes for this
 *   -    Jul 95: Guenther Kelleter <[e-mail]>:
 *                Programmable Falcon video modes
 *                (thanks to Christian Cartus for documentation
 *                of VIDEL registers).
 *   - 27 Dec 95: Guenther: Implemented user definable video modes "user[0-7]"
 *                on minor 24...31. "user0" may be set on commandline by
 *                "R<x>;<y>;<depth>". (Makes sense only on Falcon)
 *                Video mode switch on Falcon now done at next VBL interrupt
 *                to avoid the annoying right shift of the screen.
 *   - 23 Sep 97: Juergen: added xres_virtual for cards like ProMST
 *                The external-part is legacy, therefore hardware-specific
 *                functions like panning/hardwarescrolling/blanking isn't
 *				  supported.
 *   - 29 Sep 97: Juergen: added Romans suggestion for pan_display
 *				  (var->xoffset was changed even if no set_screen_base avail.)
 *	 - 05 Oct 97: Juergen: extfb (PACKED_PIXEL) is FB_PSEUDOCOLOR 'cause
 *				  we know how to set the colors
 *				  ext_*palette: read from ext_colors (former MV300_colors)
 *							    write to ext_colors and RAMDAC
 *
 * To do:
 *   - For the Falcon it is not possible to set random video modes on
 *     SM124 and SC/TV, only the bootup resolution is supported.
 *
 */

#define ATAFB_TT
#define ATAFB_STE
#define ATAFB_EXT
#define ATAFB_FALCON

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/init.h>

#include <asm/setup.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/io.h>

#include <asm/atarihw.h>
#include <asm/atariints.h>
#include <asm/atari_stram.h>

#include <linux/fb.h>
#include <asm/atarikb.h>

#include <video/fbcon.h>
#include <video/fbcon-cfb8.h>
#include <video/fbcon-cfb16.h>
#include <video/fbcon-iplan2p2.h>
#include <video/fbcon-iplan2p4.h>
#include <video/fbcon-iplan2p8.h>
#include <video/fbcon-mfb.h>


#define SWITCH_ACIA 0x01		/* modes for switch on OverScan */
#define SWITCH_SND6 0x40
#define SWITCH_SND7 0x80
#define SWITCH_NONE 0x00


#define up(x, r) (((x) + (r) - 1) & ~((r)-1))


static int default_par=0;	/* default resolution (0=none) */

static unsigned long default_mem_req=0;

static int hwscroll=-1;

static int use_hwscroll = 1;

static int sttt_xres=640,st_yres=400,tt_yres=480;
static int sttt_xres_virtual=640,sttt_yres_virtual=400;
static int ovsc_offset=0, ovsc_addlen=0;

static struct atafb_par {
	void *screen_base;
	int yres_virtual;
#if defined ATAFB_TT || defined ATAFB_STE
	union {
		struct {
			int mode;
			int sync;
		} tt, st;
#endif
#ifdef ATAFB_FALCON
		struct falcon_hw {
			/* Here are fields for storing a video mode, as direct
			 * parameters for the hardware.
			 */
			short sync;
			short line_width;
			short line_offset;
			short st_shift;
			short f_shift;
			short vid_control;
			short vid_mode;
			short xoffset;
			short hht, hbb, hbe, hdb, hde, hss;
			short vft, vbb, vbe, vdb, vde, vss;
			/* auxiliary information */
			short mono;
			short ste_mode;
			short bpp;
		} falcon;
#endif
		/* Nothing needed for external mode */
	} hw;
} current_par;

/* Don't calculate an own resolution, and thus don't change the one found when
 * booting (currently used for the Falcon to keep settings for internal video
 * hardware extensions (e.g. ScreenBlaster)  */
static int DontCalcRes = 0; 

#ifdef ATAFB_FALCON
#define HHT hw.falcon.hht
#define HBB hw.falcon.hbb
#define HBE hw.falcon.hbe
#define HDB hw.falcon.hdb
#define HDE hw.falcon.hde
#define HSS hw.falcon.hss
#define VFT hw.falcon.vft
#define VBB hw.falcon.vbb
#define VBE hw.falcon.vbe
#define VDB hw.falcon.vdb
#define VDE hw.falcon.vde
#define VSS hw.falcon.vss
#define VCO_CLOCK25		0x04
#define VCO_CSYPOS		0x10
#define VCO_VSYPOS		0x20
#define VCO_HSYPOS		0x40
#define VCO_SHORTOFFS	0x100
#define VMO_DOUBLE		0x01
#define VMO_INTER		0x02
#define VMO_PREMASK		0x0c
#endif

static struct fb_info fb_info;

static void *screen_base;	/* base address of screen */
static void *real_screen_base;	/* (only for Overscan) */

static int screen_len;

static int current_par_valid=0; 

static int currcon=0;

static int mono_moni=0;

static struct display disp;


#ifdef ATAFB_EXT
/* external video handling */

static unsigned			external_xres;
static unsigned			external_xres_virtual;
static unsigned			external_yres;
/* not needed - atafb will never support panning/hardwarescroll with external
 * static unsigned		external_yres_virtual;	
*/

static unsigned			external_depth;
static int				external_pmode;
static void *external_addr = 0;
static unsigned long	external_len;
static unsigned long	external_vgaiobase = 0;
static unsigned int		external_bitspercol = 6;

/* 
JOE <[e-mail]>: 
added card type for external driver, is only needed for
colormap handling.
*/

enum cardtype { IS_VGA, IS_MV300 };
static enum cardtype external_card_type = IS_VGA;

/*
The MV300 mixes the color registers. So we need an array of munged
indices in order to access the correct reg.
*/
static int MV300_reg_1bit[2]={0,1};
static int MV300_reg_4bit[16]={
0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15 };
static int MV300_reg_8bit[256]={
0, 128, 64, 192, 32, 160, 96, 224, 16, 144, 80, 208, 48, 176, 112, 240, 
8, 136, 72, 200, 40, 168, 104, 232, 24, 152, 88, 216, 56, 184, 120, 248, 
4, 132, 68, 196, 36, 164, 100, 228, 20, 148, 84, 212, 52, 180, 116, 244, 
12, 140, 76, 204, 44, 172, 108, 236, 28, 156, 92, 220, 60, 188, 124, 252, 
2, 130, 66, 194, 34, 162, 98, 226, 18, 146, 82, 210, 50, 178, 114, 242, 
10, 138, 74, 202, 42, 170, 106, 234, 26, 154, 90, 218, 58, 186, 122, 250, 
6, 134, 70, 198, 38, 166, 102, 230, 22, 150, 86, 214, 54, 182, 118, 246, 
14, 142, 78, 206, 46, 174, 110, 238, 30, 158, 94, 222, 62, 190, 126, 254, 
1, 129, 65, 193, 33, 161, 97, 225, 17, 145, 81, 209, 49, 177, 113, 241, 
9, 137, 73, 201, 41, 169, 105, 233, 25, 153, 89, 217, 57, 185, 121, 249, 
5, 133, 69, 197, 37, 165, 101, 229, 21, 149, 85, 213, 53, 181, 117, 245, 
13, 141, 77, 205, 45, 173, 109, 237, 29, 157, 93, 221, 61, 189, 125, 253, 
3, 131, 67, 195, 35, 163, 99, 227, 19, 147, 83, 211, 51, 179, 115, 243, 
11, 139, 75, 203, 43, 171, 107, 235, 27, 155, 91, 219, 59, 187, 123, 251, 
7, 135, 71, 199, 39, 167, 103, 231, 23, 151, 87, 215, 55, 183, 119, 247, 
15, 143, 79, 207, 47, 175, 111, 239, 31, 159, 95, 223, 63, 191, 127, 255 }; 

static int *MV300_reg = MV300_reg_8bit;

/*
And on the MV300 it's difficult to read out the hardware palette. So we
just keep track of the set colors in our own array here, and use that!
*/

static struct { unsigned char red,green,blue,pad; } ext_color[256];
#endif /* ATAFB_EXT */


static int inverse=0;

extern int fontheight_8x8;
extern int fontwidth_8x8;
extern unsigned char fontdata_8x8[];

extern int fontheight_8x16;
extern int fontwidth_8x16;
extern unsigned char fontdata_8x16[];

/* ++roman: This structure abstracts from the underlying hardware (ST(e),
 * TT, or Falcon.
 *
 * int (*detect)( void )
 *   This function should detect the current video mode settings and
 *   store them in atafb_predefined[0] for later reference by the
 *   user. Return the index+1 of an equivalent predefined mode or 0
 *   if there is no such.
 * 
 * int (*encode_fix)( struct fb_fix_screeninfo *fix,
 *                    struct atafb_par *par )
 *   This function should fill in the 'fix' structure based on the
 *   values in the 'par' structure.
 *   
 * int (*decode_var)( struct fb_var_screeninfo *var,
 *                    struct atafb_par *par )
 *   Get the video params out of 'var'. If a value doesn't fit, round
 *   it up, if it's too big, return EINVAL.
 *   Round up in the following order: bits_per_pixel, xres, yres, 
 *   xres_virtual, yres_virtual, xoffset, yoffset, grayscale, bitfields, 
 *   horizontal timing, vertical timing.
 *
 * int (*encode_var)( struct fb_var_screeninfo *var,
 *                    struct atafb_par *par );
 *   Fill the 'var' structure based on the values in 'par' and maybe
 *   other values read out of the hardware.
 *   
 * void (*get_par)( struct atafb_par *par )
 *   Fill the hardware's 'par' structure.
 *   
 * void (*set_par)( struct atafb_par *par )
 *   Set the hardware according to 'par'.
 *   
 * int (*setcolreg)( unsigned regno, unsigned red,
 *                   unsigned green, unsigned blue,
 *                   unsigned transp, struct fb_info *info )
 *   Set a single color register. The values supplied are already
 *   rounded down to the hardware's capabilities (according to the
 *   entries in the var structure). Return != 0 for invalid regno.
 *
 * int (*getcolreg)( unsigned regno, unsigned *red,
 *                   unsigned *green, unsigned *blue,
 *                   unsigned *transp, struct fb_info *info )
 *   Read a single color register and split it into
 *   colors/transparent. Return != 0 for invalid regno.
 *
 * void (*set_screen_base)(void *s_base)
 *   Set the base address of the displayed frame buffer. Only called
 *   if yres_virtual > yres or xres_virtual > xres.
 *
 * int (*blank)( int blank_mode )
 *   Blank the screen if blank_mode!=0, else unblank. If blank==NULL then
 *   the caller blanks by setting the CLUT 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, 3:suspend hsync, 4: powerdown.
 */

static struct fb_hwswitch {
	int  (*detect)( void );
	int  (*encode_fix)( struct fb_fix_screeninfo *fix,
						struct atafb_par *par );
	int  (*decode_var)( struct fb_var_screeninfo *var,
						struct atafb_par *par );
	int  (*encode_var)( struct fb_var_screeninfo *var,
						struct atafb_par *par );
	void (*get_par)( struct atafb_par *par );
	void (*set_par)( struct atafb_par *par );
	int  (*getcolreg)( unsigned regno, unsigned *red,
					   unsigned *green, unsigned *blue,
					   unsigned *transp, struct fb_info *info );
	int  (*setcolreg)( unsigned regno, unsigned red,
					   unsigned green, unsigned blue,
					   unsigned transp, struct fb_info *info );
	void (*set_screen_base)(void *s_base);
	int  (*blank)( int blank_mode );
	int  (*pan_display)( struct fb_var_screeninfo *var,
						 struct atafb_par *par);
} *fbhw;

static char *autodetect_names[] = {"autodetect", NULL};
static char *stlow_names[] = {"stlow", NULL};
static char *stmid_names[] = {"stmid", "default5", NULL};
static char *sthigh_names[] = {"sthigh", "default4", NULL};
static char *ttlow_names[] = {"ttlow", NULL};
static char *ttmid_names[]= {"ttmid", "default1", NULL};
static char *tthigh_names[]= {"tthigh", "default2", NULL};
static char *vga2_names[] = {"vga2", NULL};
static char *vga4_names[] = {"vga4", NULL};
static char *vga16_names[] = {"vga16", "default3", NULL};
static char *vga256_names[] = {"vga256", NULL};
static char *falh2_names[] = {"falh2", NULL};
static char *falh16_names[] = {"falh16", NULL};

static char **fb_var_names[] = {
	/* Writing the name arrays directly in this array (via "(char *[]){...}")
	 * crashes gcc 2.5.8 (sigsegv) if the inner array
	 * contains more than two items. I've also seen that all elements
	 * were identical to the last (my cross-gcc) :-(*/
	autodetect_names,
	stlow_names,
	stmid_names,
	sthigh_names,
	ttlow_names,
	ttmid_names,
	tthigh_names,
	vga2_names,
	vga4_names,
	vga16_names,
	vga256_names,
	falh2_names,
	falh16_names,
	NULL
	/* ,NULL */ /* this causes a sigsegv on my gcc-2.5.8 */
};

static struct fb_var_screeninfo atafb_predefined[] = {
 	/*
 	 * yres_virtual==0 means use hw-scrolling if possible, else yres
 	 */
 	{ /* autodetect */
	  0, 0, 0, 0, 0, 0, 0, 0,   		/* xres-grayscale */
	  {0, 0, 0}, {0, 0, 0}, {0, 0, 0}, {0, 0, 0}, 	/* red green blue tran*/
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
 	{ /* st low */
	  320, 200, 320, 0, 0, 0, 4, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* st mid */
	  640, 200, 640, 0, 0, 0, 2, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* st high */
	  640, 400, 640, 0, 0, 0, 1, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* tt low */
	  320, 480, 320, 0, 0, 0, 8, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* tt mid */
	  640, 480, 640, 0, 0, 0, 4, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* tt high */
	  1280, 960, 1280, 0, 0, 0, 1, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* vga2 */
	  640, 480, 640, 0, 0, 0, 1, 0,
	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* vga4 */
	  640, 480, 640, 0, 0, 0, 2, 0,
	  {0, 4, 0}, {0, 4, 0}, {0, 4, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* vga16 */
	  640, 480, 640, 0, 0, 0, 4, 0,
	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* vga256 */
	  640, 480, 640, 0, 0, 0, 8, 0,
	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* falh2 */
	  896, 608, 896, 0, 0, 0, 1, 0,
	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
	{ /* falh16 */
	  896, 608, 896, 0, 0, 0, 4, 0,
	  {0, 6, 0}, {0, 6, 0}, {0, 6, 0}, {0, 0, 0},
	  0, 0, -1, -1, 0, 0, 0, 0, 0, 0, 0, 0 },
};

static int num_atafb_predefined=ARRAY_SIZE(atafb_predefined);


static int
get_video_mode(char *vname)
{
    char ***name_list;
    char **name;
    int i;
    name_list=fb_var_names;
    for (i = 0 ; i < num_atafb_predefined ; i++) {
	name=*(name_list++);
	if (! name || ! *name)
	    break;
	while (*name) {
	    if (! strcmp(vname, *name))
		return i+1;
	    name++;
	}
    }
    return 0;
}



/* ------------------- TT specific functions ---------------------- */

#ifdef ATAFB_TT

static int tt_encode_fix( struct fb_fix_screeninfo *fix,
						  struct atafb_par *par )

{
	int mode;

	strcpy(fix->id,"Atari Builtin");
	fix->smem_start = (unsigned long)real_screen_base;
	fix->smem_len = screen_len;
	fix->type=FB_TYPE_INTERLEAVED_PLANES;
	fix->type_aux=2;
	fix->visual=FB_VISUAL_PSEUDOCOLOR;
	mode = par->hw.tt.mode & TT_SHIFTER_MODEMASK;
	if (mode == TT_SHIFTER_TTHIGH || mode == TT_SHIFTER_STHIGH) {