offb.c

Linux环境下视频显示卡设备的驱动程序源代码

		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
		if (par->cmap_adr)
			par->cmap_type = cmap_M3A;
	} else if (dp && !strncmp(name, "ATY,RageM3pB", 12)) {
		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
		if (par->cmap_adr)
			par->cmap_type = cmap_M3B;
	} else if (dp && !strncmp(name, "ATY,Rage6", 9)) {
		par->cmap_adr = offb_map_reg(dp, 1, 0, 0x1fff);
		if (par->cmap_adr)
			par->cmap_type = cmap_radeon;
	} else if (!strncmp(name, "ATY,", 4)) {
		unsigned long base = address & 0xff000000UL;
		par->cmap_adr =
			ioremap(base + 0x7ff000, 0x1000) + 0xcc0;
		par->cmap_data = par->cmap_adr + 1;
		par->cmap_type = cmap_m64;
	} else if (dp && (of_device_is_compatible(dp, "pci1014,b7") ||
			  of_device_is_compatible(dp, "pci1014,21c"))) {
		par->cmap_adr = offb_map_reg(dp, 0, 0x6000, 0x1000);
		if (par->cmap_adr)
			par->cmap_type = cmap_gxt2000;
	} else if (dp && !strncmp(name, "vga,Display-", 12)) {
		/* Look for AVIVO initialized by SLOF */
		struct device_node *pciparent = of_get_parent(dp);
		const u32 *vid, *did;
		vid = of_get_property(pciparent, "vendor-id", NULL);
		did = of_get_property(pciparent, "device-id", NULL);
		/* This will match most R5xx */
		if (vid && did && *vid == 0x1002 &&
		    ((*did >= 0x7100 && *did < 0x7800) ||
		     (*did >= 0x9400))) {
			par->cmap_adr = offb_map_reg(pciparent, 2, 0, 0x10000);
			if (par->cmap_adr)
				par->cmap_type = cmap_avivo;
		}
		of_node_put(pciparent);
	}
	info->fix.visual = (par->cmap_type != cmap_unknown) ?
		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_STATIC_PSEUDOCOLOR;
}

static void __init offb_init_fb(const char *name, const char *full_name,
				int width, int height, int depth,
				int pitch, unsigned long address,
				int foreign_endian, struct device_node *dp)
{
	unsigned long res_size = pitch * height * (depth + 7) / 8;
	struct offb_par *par = &default_par;
	unsigned long res_start = address;
	struct fb_fix_screeninfo *fix;
	struct fb_var_screeninfo *var;
	struct fb_info *info;
	int size;

	if (!request_mem_region(res_start, res_size, "offb"))
		return;

	printk(KERN_INFO
	       "Using unsupported %dx%d %s at %lx, depth=%d, pitch=%d\n",
	       width, height, name, address, depth, pitch);
	if (depth != 8 && depth != 15 && depth != 16 && depth != 32) {
		printk(KERN_ERR "%s: can't use depth = %d\n", full_name,
		       depth);
		release_mem_region(res_start, res_size);
		return;
	}

	size = sizeof(struct fb_info) + sizeof(u32) * 16;

	info = kmalloc(size, GFP_ATOMIC);
	
	if (info == 0) {
		release_mem_region(res_start, res_size);
		return;
	}
	memset(info, 0, size);

	fix = &info->fix;
	var = &info->var;
	info->par = par;

	strcpy(fix->id, "OFfb ");
	strncat(fix->id, name, sizeof(fix->id) - sizeof("OFfb "));
	fix->id[sizeof(fix->id) - 1] = '\0';

	var->xres = var->xres_virtual = width;
	var->yres = var->yres_virtual = height;
	fix->line_length = pitch;

	fix->smem_start = address;
	fix->smem_len = pitch * height;
	fix->type = FB_TYPE_PACKED_PIXELS;
	fix->type_aux = 0;

	par->cmap_type = cmap_unknown;
	if (depth == 8)
		offb_init_palette_hacks(info, dp, name, address);
	else
		fix->visual = FB_VISUAL_TRUECOLOR;

	var->xoffset = var->yoffset = 0;
	switch (depth) {
	case 8:
		var->bits_per_pixel = 8;
		var->red.offset = 0;
		var->red.length = 8;
		var->green.offset = 0;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 15:		/* RGB 555 */
		var->bits_per_pixel = 16;
		var->red.offset = 10;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 5;
		var->blue.offset = 0;
		var->blue.length = 5;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 16:		/* RGB 565 */
		var->bits_per_pixel = 16;
		var->red.offset = 11;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 6;
		var->blue.offset = 0;
		var->blue.length = 5;
		var->transp.offset = 0;
		var->transp.length = 0;
		break;
	case 32:		/* RGB 888 */
		var->bits_per_pixel = 32;
		var->red.offset = 16;
		var->red.length = 8;
		var->green.offset = 8;
		var->green.length = 8;
		var->blue.offset = 0;
		var->blue.length = 8;
		var->transp.offset = 24;
		var->transp.length = 8;
		break;
	}
	var->red.msb_right = var->green.msb_right = var->blue.msb_right =
	    var->transp.msb_right = 0;
	var->grayscale = 0;
	var->nonstd = 0;
	var->activate = 0;
	var->height = var->width = -1;
	var->pixclock = 10000;
	var->left_margin = var->right_margin = 16;
	var->upper_margin = var->lower_margin = 16;
	var->hsync_len = var->vsync_len = 8;
	var->sync = 0;
	var->vmode = FB_VMODE_NONINTERLACED;

	info->fbops = &offb_ops;
	info->screen_base = ioremap(address, fix->smem_len);
	info->pseudo_palette = (void *) (info + 1);
	info->flags = FBINFO_DEFAULT | foreign_endian;

	fb_alloc_cmap(&info->cmap, 256, 0);

	if (register_framebuffer(info) < 0) {
		iounmap(par->cmap_adr);
		par->cmap_adr = NULL;
		iounmap(info->screen_base);
		kfree(info);
		release_mem_region(res_start, res_size);
		return;
	}

	printk(KERN_INFO "fb%d: Open Firmware frame buffer device on %s\n",
	       info->node, full_name);
}


static void __init offb_init_nodriver(struct device_node *dp, int no_real_node)
{
	unsigned int len;
	int i, width = 640, height = 480, depth = 8, pitch = 640;
	unsigned int flags, rsize, addr_prop = 0;
	unsigned long max_size = 0;
	u64 rstart, address = OF_BAD_ADDR;
	const u32 *pp, *addrp, *up;
	u64 asize;
	int foreign_endian = 0;

#ifdef __BIG_ENDIAN
	if (of_get_property(dp, "little-endian", NULL))
		foreign_endian = FBINFO_FOREIGN_ENDIAN;
#else
	if (of_get_property(dp, "big-endian", NULL))
		foreign_endian = FBINFO_FOREIGN_ENDIAN;
#endif

	pp = of_get_property(dp, "linux,bootx-depth", &len);
	if (pp == NULL)
		pp = of_get_property(dp, "depth", &len);
	if (pp && len == sizeof(u32))
		depth = *pp;

	pp = of_get_property(dp, "linux,bootx-width", &len);
	if (pp == NULL)
		pp = of_get_property(dp, "width", &len);
	if (pp && len == sizeof(u32))
		width = *pp;

	pp = of_get_property(dp, "linux,bootx-height", &len);
	if (pp == NULL)
		pp = of_get_property(dp, "height", &len);
	if (pp && len == sizeof(u32))
		height = *pp;

	pp = of_get_property(dp, "linux,bootx-linebytes", &len);
	if (pp == NULL)
		pp = of_get_property(dp, "linebytes", &len);
	if (pp && len == sizeof(u32) && (*pp != 0xffffffffu))
		pitch = *pp;
	else
		pitch = width * ((depth + 7) / 8);

	rsize = (unsigned long)pitch * (unsigned long)height;

	/* Ok, now we try to figure out the address of the framebuffer.
	 *
	 * Unfortunately, Open Firmware doesn't provide a standard way to do
	 * so. All we can do is a dodgy heuristic that happens to work in
	 * practice. On most machines, the "address" property contains what
	 * we need, though not on Matrox cards found in IBM machines. What I've
	 * found that appears to give good results is to go through the PCI
	 * ranges and pick one that is both big enough and if possible encloses
	 * the "address" property. If none match, we pick the biggest
	 */
	up = of_get_property(dp, "linux,bootx-addr", &len);
	if (up == NULL)
		up = of_get_property(dp, "address", &len);
	if (up && len == sizeof(u32))
		addr_prop = *up;

	/* Hack for when BootX is passing us */
	if (no_real_node)
		goto skip_addr;

	for (i = 0; (addrp = of_get_address(dp, i, &asize, &flags))
		     != NULL; i++) {
		int match_addrp = 0;

		if (!(flags & IORESOURCE_MEM))
			continue;
		if (asize < rsize)
			continue;
		rstart = of_translate_address(dp, addrp);
		if (rstart == OF_BAD_ADDR)
			continue;
		if (addr_prop && (rstart <= addr_prop) &&
		    ((rstart + asize) >= (addr_prop + rsize)))
			match_addrp = 1;
		if (match_addrp) {
			address = addr_prop;
			break;
		}
		if (rsize > max_size) {
			max_size = rsize;
			address = OF_BAD_ADDR;
 		}

		if (address == OF_BAD_ADDR)
			address = rstart;
	}
 skip_addr:
	if (address == OF_BAD_ADDR && addr_prop)
		address = (u64)addr_prop;
	if (address != OF_BAD_ADDR) {
		/* kludge for valkyrie */
		if (strcmp(dp->name, "valkyrie") == 0)
			address += 0x1000;
		offb_init_fb(no_real_node ? "bootx" : dp->name,
			     no_real_node ? "display" : dp->full_name,
			     width, height, depth, pitch, address,
			     foreign_endian, no_real_node ? NULL : dp);
	}
}

static int __init offb_init(void)
{
	struct device_node *dp = NULL, *boot_disp = NULL;

	if (fb_get_options("offb", NULL))
		return -ENODEV;

	/* Check if we have a MacOS display without a node spec */
	if (of_get_property(of_chosen, "linux,bootx-noscreen", NULL) != NULL) {
		/* The old code tried to work out which node was the MacOS
		 * display based on the address. I'm dropping that since the
		 * lack of a node spec only happens with old BootX versions
		 * (users can update) and with this code, they'll still get
		 * a display (just not the palette hacks).
		 */
		offb_init_nodriver(of_chosen, 1);
	}

	for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
		if (of_get_property(dp, "linux,opened", NULL) &&
		    of_get_property(dp, "linux,boot-display", NULL)) {
			boot_disp = dp;
			offb_init_nodriver(dp, 0);
		}
	}
	for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
		if (of_get_property(dp, "linux,opened", NULL) &&
		    dp != boot_disp)
			offb_init_nodriver(dp, 0);
	}

	return 0;
}


module_init(offb_init);
MODULE_LICENSE("GPL");