pmacs3/code_examples/imacfb.c

/*
 * framebuffer driver for Intel Based Mac's
 *
 * (c) 2006 Edgar Hucek <gimli@dark-green.com>
 * Original imac driver written by Gerd Knorr <kraxel@goldbach.in-berlin.de>
 *
 */

#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/delay.h>
#include <linux/fb.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/platform_device.h>

#include <video/vga.h>
#include <asm/io.h>
#include <asm/mtrr.h>

#define dac_reg	(0x3c8)
#define dac_val	(0x3c9)

typedef enum _MAC_TAPE {
	M_I17,
	M_I20,
	M_MINI,
	M_NEW
} MAC_TAPE;

/* --------------------------------------------------------------------- */

static struct fb_var_screeninfo imacfb_defined __initdata = {
      	.activate	= FB_ACTIVATE_NOW,
	.height		= -1,
	.width		= -1,
	.right_margin	= 32,
	.upper_margin	= 16,
	.lower_margin	= 4,
	.vsync_len	= 4,
	.vmode		= FB_VMODE_NONINTERLACED,
};

static struct fb_fix_screeninfo imacfb_fix __initdata = {
	.id	= "IMAC VGA",
	.type	= FB_TYPE_PACKED_PIXELS,
	.accel	= FB_ACCEL_NONE,
};

static int             inverse   = 0;
static int             mtrr      = 0; /* disable mtrr */
static int	       vram_remap __initdata = 0; /* Set amount of memory to be used */
static int	       vram_total __initdata = 0; /* Set total amount of memory */
static int             depth;
static int             model = M_NEW;
static int             manual_height = 0;
static int             manual_width = 0;

/* --------------------------------------------------------------------- */

static int imacfb_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.
	 */
	
	if (regno >= info->cmap.len)
		return 1;

	if (regno < 16 && info->var.bits_per_pixel != 8) {
		switch (info->var.bits_per_pixel) {
		case 16:
			if (info->var.red.offset == 10) {
				/* 1:5:5:5 */
				((u32*) (info->pseudo_palette))[regno] =
					((red   & 0xf800) >>  1) |
					((green & 0xf800) >>  6) |
					((blue  & 0xf800) >> 11);
			} else {
				/* 0:5:6:5 */
				((u32*) (info->pseudo_palette))[regno] =
					((red   & 0xf800)      ) |
					((green & 0xfc00) >>  5) |
					((blue  & 0xf800) >> 11);
			}
			break;
		case 24:
		case 32:
			red   >>= 8;
			green >>= 8;
			blue  >>= 8;
			((u32 *)(info->pseudo_palette))[regno] =
				(red   << info->var.red.offset)   |
				(green << info->var.green.offset) |
				(blue  << info->var.blue.offset);
			break;
		}
	}

	return 0;
}

static struct fb_ops imacfb_ops = {
	.owner		= THIS_MODULE,
	.fb_setcolreg	= imacfb_setcolreg,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

static int __init imacfb_setup(char *options)
{
	char *this_opt;
	
	if (!options || !*options)
		return 0;
	
	while ((this_opt = strsep(&options, ",")) != NULL) {
		if (!*this_opt) continue;
		
		if (! strcmp(this_opt, "inverse"))
			inverse=1;
		else if (! strncmp(this_opt, "mtrr:", 5))
			mtrr = simple_strtoul(this_opt+5, NULL, 0);
		else if (! strcmp(this_opt, "nomtrr"))
			mtrr=0;
		else if (! strncmp(this_opt, "vtotal:", 7))
			vram_total = simple_strtoul(this_opt+7, NULL, 0);
		else if (! strncmp(this_opt, "vremap:", 7))
			vram_remap = simple_strtoul(this_opt+7, NULL, 0);
		else if (! strcmp(this_opt, "i17"))
			model = M_I17;
		else if (! strcmp(this_opt, "i20"))
			model = M_I20;
		else if (! strcmp(this_opt, "mini"))
			model = M_MINI;
                else if (! strncmp(this_opt, "height:", 7))
                        manual_height = simple_strtoul(this_opt+7, NULL, 0);
                else if (! strncmp(this_opt, "width:", 6))
                        manual_width = simple_strtoul(this_opt+6, NULL, 0);
	}
	return 0;
}

#define	DEFAULT_FB_MEM	1024*1024*16

static int __init imacfb_probe(struct platform_device *dev)
{
	struct fb_info *info;
	int err;
	unsigned int size_vmode;
	unsigned int size_remap;
	unsigned int size_total;

	screen_info.lfb_base = 0x80010000;
	screen_info.lfb_depth = 32;
	screen_info.lfb_size = DEFAULT_FB_MEM / 0x10000;
	screen_info.pages=1;
	screen_info.blue_size = 8;
	screen_info.blue_pos = 0;
	screen_info.green_size = 8;
	screen_info.green_pos = 8;
	screen_info.red_size = 8;
	screen_info.red_pos = 16;
	screen_info.rsvd_size = 8;
	screen_info.rsvd_pos = 24;

	switch(model) {
		case M_I17:
			screen_info.lfb_width = 1440;
			screen_info.lfb_height = 900;
			screen_info.lfb_linelength = 1472 * 4;
			break;
		case M_NEW:
		case M_I20:
			screen_info.lfb_width = 1680;
			screen_info.lfb_height = 1050;
			screen_info.lfb_linelength = 1728 * 4;
			break;
		case M_MINI:
			screen_info.lfb_width = 1024;
			screen_info.lfb_height = 768;
			screen_info.lfb_linelength = 2048 * 4;
			break;
 	}

	/* if the user wants to manually specify height/width,
	   we will override the defaults */
	/* TODO: eventually get auto-detection working */
        if(manual_height > 0)
	        screen_info.lfb_height = manual_height;
        if(manual_width > 0)
	        screen_info.lfb_width = manual_width;

	/*
	static void *videomemory;
	static u_long videomemorysize = (64*1024*1024);
	videomemory = ioremap(0x80000000,videomemorysize);
	memset(videomemory, 0x99, videomemorysize);
	*/

	imacfb_fix.smem_start = screen_info.lfb_base;
	imacfb_defined.bits_per_pixel = screen_info.lfb_depth;
	if (15 == imacfb_defined.bits_per_pixel)
		imacfb_defined.bits_per_pixel = 16;
	imacfb_defined.xres = screen_info.lfb_width;
	imacfb_defined.yres = screen_info.lfb_height;
	imacfb_fix.line_length = screen_info.lfb_linelength;
	imacfb_fix.visual   = (imacfb_defined.bits_per_pixel == 8) ?
		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR;

	/*   size_vmode -- that is the amount of memory needed for the
	 *                 used video mode, i.e. the minimum amount of
	 *                 memory we need. */
	size_vmode = imacfb_defined.yres * imacfb_fix.line_length;

	/*   size_total -- all video memory we have. Used for mtrr
	 *                 entries, ressource allocation and bounds
	 *                 checking. */
	size_total = screen_info.lfb_size * 65536;
	if (vram_total)
		size_total = vram_total * 1024 * 1024;
	if (size_total < size_vmode)
		size_total = size_vmode;

	/*   size_remap -- the amount of video memory we are going to
	 *                 use for imacfb.  With modern cards it is no
	 *                 option to simply use size_total as that
	 *                 wastes plenty of kernel address space. */
	size_remap  = size_vmode * 2;
	if (vram_remap)
		size_remap = vram_remap * 1024 * 1024;
	if (size_remap < size_vmode)
		size_remap = size_vmode;
	if (size_remap > size_total)
		size_remap = size_total;
	imacfb_fix.smem_len = size_remap;

#ifndef __i386__
	screen_info.imacpm_seg = 0;
#endif

	if (!request_mem_region(imacfb_fix.smem_start, size_total, "imacfb")) {
		printk(KERN_WARNING
		       "imacfb: cannot reserve video memory at 0x%lx\n",
			imacfb_fix.smem_start);
		/* We cannot make this fatal. Sometimes this comes from magic
		   spaces our resource handlers simply don't know about */
	}

	info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
	if (!info) {
		release_mem_region(imacfb_fix.smem_start, size_total);
		return -ENOMEM;
	}
	info->pseudo_palette = info->par;
	info->par = NULL;

	info->screen_base = ioremap(imacfb_fix.smem_start, imacfb_fix.smem_len);
	if (!info->screen_base) {
		printk(KERN_ERR
		       "imacfb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n",
			imacfb_fix.smem_len, imacfb_fix.smem_start);
		err = -EIO;
		goto err;
	}

	printk(KERN_INFO "imacfb: framebuffer at 0x%lx, mapped to 0x%p, "
	       "using %dk, total %dk\n",
	       imacfb_fix.smem_start, info->screen_base,
	       size_remap/1024, size_total/1024);
	printk(KERN_INFO "imacfb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
	       imacfb_defined.xres, imacfb_defined.yres, imacfb_defined.bits_per_pixel, imacfb_fix.line_length, screen_info.pages);

	imacfb_defined.xres_virtual = imacfb_defined.xres;
	imacfb_defined.yres_virtual = imacfb_fix.smem_len / imacfb_fix.line_length;
	printk(KERN_INFO "imacfb: scrolling: redraw\n");
	imacfb_defined.yres_virtual = imacfb_defined.yres;

	/* some dummy values for timing to make fbset happy */
	imacfb_defined.pixclock     = 10000000 / imacfb_defined.xres * 1000 / imacfb_defined.yres;
	imacfb_defined.left_margin  = (imacfb_defined.xres / 8) & 0xf8;
	imacfb_defined.hsync_len    = (imacfb_defined.xres / 8) & 0xf8;
	
	imacfb_defined.red.offset    = screen_info.red_pos;
	imacfb_defined.red.length    = screen_info.red_size;
	imacfb_defined.green.offset  = screen_info.green_pos;
	imacfb_defined.green.length  = screen_info.green_size;
	imacfb_defined.blue.offset   = screen_info.blue_pos;
	imacfb_defined.blue.length   = screen_info.blue_size;
	imacfb_defined.transp.offset = screen_info.rsvd_pos;
	imacfb_defined.transp.length = screen_info.rsvd_size;

	if (imacfb_defined.bits_per_pixel <= 8) {
		depth = imacfb_defined.green.length;
		imacfb_defined.red.length =
		imacfb_defined.green.length =
		imacfb_defined.blue.length =
		imacfb_defined.bits_per_pixel;
	}

	printk(KERN_INFO "imacfb: %s: "
	       "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
	       (imacfb_defined.bits_per_pixel > 8) ?
	       "Truecolor" : "Pseudocolor",
	       screen_info.rsvd_size,
	       screen_info.red_size,
	       screen_info.green_size,
	       screen_info.blue_size,
	       screen_info.rsvd_pos,
	       screen_info.red_pos,
	       screen_info.green_pos,
	       screen_info.blue_pos);

	imacfb_fix.ypanstep  = 0;
	imacfb_fix.ywrapstep = 0;

	/* request failure does not faze us, as vgacon probably has this
	 * region already (FIXME) */
	request_region(0x3c0, 32, "imacfb");

#ifdef CONFIG_MTRR
	if (mtrr) {
		unsigned int temp_size = size_total;
		unsigned int type = 0;

		switch (mtrr) {
		case 1:
			type = MTRR_TYPE_UNCACHABLE;
			break;
		case 2:
			type = MTRR_TYPE_WRBACK;
			break;
		case 3:
			type = MTRR_TYPE_WRCOMB;
			break;
		case 4:
			type = MTRR_TYPE_WRTHROUGH;
			break;
		default:
			type = 0;
			break;
		}

		if (type) {
			int rc;

			/* Find the largest power-of-two */
			while (temp_size & (temp_size - 1))
				temp_size &= (temp_size - 1);

			/* Try and find a power of two to add */
			do {
				rc = mtrr_add(imacfb_fix.smem_start, temp_size,
					      type, 1);
				temp_size >>= 1;
			} while (temp_size >= PAGE_SIZE && rc == -EINVAL);
		}
	}
#endif
	
	info->fbops = &imacfb_ops;
	info->var = imacfb_defined;
	info->fix = imacfb_fix;
	info->flags = FBINFO_FLAG_DEFAULT;

	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
		err = -ENOMEM;
		goto err;
	}
	if (register_framebuffer(info)<0) {
		err = -EINVAL;
		fb_dealloc_cmap(&info->cmap);
		goto err;
	}
	printk(KERN_INFO "fb%d: %s frame buffer device\n",
	       info->node, info->fix.id);
	return 0;
err:
	framebuffer_release(info);
	release_mem_region(imacfb_fix.smem_start, size_total);
	return err;
}

static struct platform_driver imacfb_driver = {
	.probe	= imacfb_probe,
	.driver	= {
		.name	= "imacfb",
	},
};

static struct platform_device imacfb_device = {
	.name	= "imacfb",
};

static int __init imacfb_init(void)
{
	int ret;
	char *option = NULL;

	/* ignore error return of fb_get_options */
	fb_get_options("imacfb", &option);
	imacfb_setup(option);
	ret = platform_driver_register(&imacfb_driver);

	if (!ret) {
		ret = platform_device_register(&imacfb_device);
		if (ret)
			platform_driver_unregister(&imacfb_driver);
	}
	return ret;
}
module_init(imacfb_init);

MODULE_LICENSE("GPL");