path: root/drivers/video/pm3fb.c

/*
 *  linux/drivers/video/pm3fb.c -- 3DLabs Permedia3 frame buffer device
 *
 *  Copyright (C) 2001 Romain Dolbeau <romain@dolbeau.org>.
 *
 *  Ported to 2.6 kernel on 1 May 2007 by Krzysztof Helt <krzysztof.h1@wp.pl>
 *	based on pm2fb.c
 *
 *  Based on code written by:
 *	   Sven Luther, <luther@dpt-info.u-strasbg.fr>
 *	   Alan Hourihane, <alanh@fairlite.demon.co.uk>
 *	   Russell King, <rmk@arm.linux.org.uk>
 *  Based on linux/drivers/video/skeletonfb.c:
 *	Copyright (C) 1997 Geert Uytterhoeven
 *  Based on linux/driver/video/pm2fb.c:
 *	Copyright (C) 1998-1999 Ilario Nardinocchi (nardinoc@CS.UniBO.IT)
 *	Copyright (C) 1999 Jakub Jelinek (jakub@redhat.com)
 *
 *  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/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/pci.h>

#include <video/pm3fb.h>

#if !defined(CONFIG_PCI)
#error "Only generic PCI cards supported."
#endif

#undef PM3FB_MASTER_DEBUG
#ifdef PM3FB_MASTER_DEBUG
#define DPRINTK(a,b...)	printk(KERN_DEBUG "pm3fb: %s: " a, __FUNCTION__ , ## b)
#else
#define DPRINTK(a,b...)
#endif

/*
 * Driver data
 */
static char *mode_option __devinitdata;

/*
 *  If your driver supports multiple boards, you should make the
 *  below data types arrays, or allocate them dynamically (using kmalloc()).
 */

/*
 * This structure defines the hardware state of the graphics card. Normally
 * you place this in a header file in linux/include/video. This file usually
 * also includes register information. That allows other driver subsystems
 * and userland applications the ability to use the same header file to
 * avoid duplicate work and easy porting of software.
 */
struct pm3_par {
	unsigned char	__iomem *v_regs;/* virtual address of p_regs */
	u32		video;		/* video flags before blanking */
	u32		base;		/* screen base (xoffset+yoffset) in 128 bits unit */
	u32 		palette[16];
};

/*
 * Here we define the default structs fb_fix_screeninfo and fb_var_screeninfo
 * if we don't use modedb. If we do use modedb see pm3fb_init how to use it
 * to get a fb_var_screeninfo. Otherwise define a default var as well.
 */
static struct fb_fix_screeninfo pm3fb_fix __devinitdata = {
	.id =		"Permedia3",
	.type =		FB_TYPE_PACKED_PIXELS,
	.visual =	FB_VISUAL_PSEUDOCOLOR,
	.xpanstep =	1,
	.ypanstep =	1,
	.ywrapstep =	0,
	.accel =	FB_ACCEL_NONE,
};

/*
 * Utility functions
 */

static inline u32 PM3_READ_REG(struct pm3_par *par, s32 off)
{
	return fb_readl(par->v_regs + off);
}

static inline void PM3_WRITE_REG(struct pm3_par *par, s32 off, u32 v)
{
	fb_writel(v, par->v_regs + off);
}

static inline void PM3_WAIT(struct pm3_par *par, u32 n)
{
	while (PM3_READ_REG(par, PM3InFIFOSpace) < n);
}

static inline void PM3_SLOW_WRITE_REG(struct pm3_par *par, s32 off, u32 v)
{
	if (par->v_regs) {
		mb();
		PM3_WAIT(par, 1);
		wmb();
		PM3_WRITE_REG(par, off, v);
	}
}

static inline void PM3_SET_INDEX(struct pm3_par *par, unsigned index)
{
	PM3_SLOW_WRITE_REG(par, PM3RD_IndexHigh, (index >> 8) & 0xff);
	PM3_SLOW_WRITE_REG(par, PM3RD_IndexLow, index & 0xff);
}

static inline void PM3_WRITE_DAC_REG(struct pm3_par *par, unsigned r, u8 v)
{
	PM3_SET_INDEX(par, r);
	wmb();
	PM3_WRITE_REG(par, PM3RD_IndexedData, v);
}

static inline void pm3fb_set_color(struct pm3_par *par, unsigned char regno,
			unsigned char r, unsigned char g, unsigned char b)
{
	PM3_SLOW_WRITE_REG(par, PM3RD_PaletteWriteAddress, regno);
	PM3_SLOW_WRITE_REG(par, PM3RD_PaletteData, r);
	PM3_SLOW_WRITE_REG(par, PM3RD_PaletteData, g);
	PM3_SLOW_WRITE_REG(par, PM3RD_PaletteData, b);
}

static void pm3fb_clear_colormap(struct pm3_par *par,
			unsigned char r, unsigned char g, unsigned char b)
{
	int i;

	for (i = 0; i < 256 ; i++) /* fill color map with white */
		pm3fb_set_color(par, i, r, g, b);

}

/* Calculating various clock parameter */
static void pm3fb_calculate_clock(unsigned long reqclock,
				unsigned char *prescale,
				unsigned char *feedback,
				unsigned char *postscale)
{
	int f, pre, post;
	unsigned long freq;
	long freqerr = 1000;
	long currerr;

	for (f = 1; f < 256; f++) {
		for (pre = 1; pre < 256; pre++) {
			for (post = 0; post < 5;