tgafb.c

Linux环境下视频显示卡设备的驱动程序源代码

	dealign = depos & 7;
	sealign = sepos & 7;

	/* ??? The documentation appears to be incorrect (or very
	   misleading) wrt how pixel shifting works in backward copy
	   mode, i.e. when PIXELSHIFT is negative.  I give up for now.
	   Do handle the common case of co-aligned backward copies,
	   but frob everything else back on generic code.  */
	if (dealign != sealign) {
		cfb_copyarea(info, area);
		return;
	}

	/* We begin the copy with the trailing pixels of the
	   unaligned destination.  */
	mask_first = (1ul << dealign) - 1;
	left = width - dealign;

	/* Care for small copies.  */
	if (dealign > width) {
		mask_first ^= (1ul << (dealign - width)) - 1;
		left = 0;
	}

	/* Next copy full words at a time.  */
	n32 = left / 32;
	left %= 32;

	/* Finally copy the unaligned head of the span.  */
	mask_last = -1 << (32 - left);

	tga_regs = par->tga_regs_base;
	tga_fb = par->tga_fb_base;

	/* Set up the MODE and PIXELSHIFT registers.  */
	__raw_writel(TGA_MODE_SBM_8BPP|TGA_MODE_COPY, tga_regs+TGA_MODE_REG);
	__raw_writel(0, tga_regs+TGA_PIXELSHIFT_REG);
	wmb();

	for (i = 0; i < height; ++i) {
		unsigned long j;
		void __iomem *sfb;
		void __iomem *dfb;

		sfb = tga_fb + sepos;
		dfb = tga_fb + depos;
		if (mask_first) {
			__raw_writel(mask_first, sfb);
			wmb();
			__raw_writel(mask_first, dfb);
			wmb();
		}

		for (j = 0; j < n32; ++j) {
			sfb -= 32;
			dfb -= 32;
			__raw_writel(0xffffffff, sfb);
			wmb();
			__raw_writel(0xffffffff, dfb);
			wmb();
		}

		if (mask_last) {
			sfb -= 32;
			dfb -= 32;
			__raw_writel(mask_last, sfb);
			wmb();
			__raw_writel(mask_last, dfb);
			wmb();
		}

		sepos += yincr;
		depos += yincr;
	}

	/* Reset the MODE register to normal.  */
	__raw_writel(TGA_MODE_SBM_8BPP|TGA_MODE_SIMPLE, tga_regs+TGA_MODE_REG);
}

static void
tgafb_copyarea(struct fb_info *info, const struct fb_copyarea *area) 
{
	unsigned long dx, dy, width, height, sx, sy, vxres, vyres;
	unsigned long line_length, bpp;

	dx = area->dx;
	dy = area->dy;
	width = area->width;
	height = area->height;
	sx = area->sx;
	sy = area->sy;
	vxres = info->var.xres_virtual;
	vyres = info->var.yres_virtual;
	line_length = info->fix.line_length;

	/* The top left corners must be in the virtual screen.  */
	if (dx > vxres || sx > vxres || dy > vyres || sy > vyres)
		return;

	/* Clip the destination.  */
	if (dx + width > vxres)
		width = vxres - dx;
	if (dy + height > vyres)
		height = vyres - dy;

	/* The source must be completely inside the virtual screen.  */
	if (sx + width > vxres || sy + height > vyres)
		return;

	bpp = info->var.bits_per_pixel;

	/* Detect copies of the entire line.  */
	if (width * (bpp >> 3) == line_length) {
		if (bpp == 8)
			copyarea_line_8bpp(info, dy, sy, height, width);
		else
			copyarea_line_32bpp(info, dy, sy, height, width);
	}

	/* ??? The documentation is unclear to me exactly how the pixelshift
	   register works in 32bpp mode.  Since I don't have hardware to test,
	   give up for now and fall back on the generic routines.  */
	else if (bpp == 32)
		cfb_copyarea(info, area);

	/* Detect overlapping source and destination that requires
	   a backward copy.  */
	else if (dy == sy && dx > sx && dx < sx + width)
		copyarea_backward_8bpp(info, dx, dy, sx, sy, height,
				       width, line_length, area);
	else
		copyarea_foreward_8bpp(info, dx, dy, sx, sy, height,
				       width, line_length);
}


/*
 *  Initialisation
 */

static void
tgafb_init_fix(struct fb_info *info)
{
	struct tga_par *par = (struct tga_par *)info->par;
	int tga_bus_pci = TGA_BUS_PCI(par->dev);
	int tga_bus_tc = TGA_BUS_TC(par->dev);
	u8 tga_type = par->tga_type;
	const char *tga_type_name = NULL;

	switch (tga_type) {
	case TGA_TYPE_8PLANE:
		if (tga_bus_pci)
			tga_type_name = "Digital ZLXp-E1";
		if (tga_bus_tc)
			tga_type_name = "Digital ZLX-E1";
		break;
	case TGA_TYPE_24PLANE:
		if (tga_bus_pci)
			tga_type_name = "Digital ZLXp-E2";
		if (tga_bus_tc)
			tga_type_name = "Digital ZLX-E2";
		break;
	case TGA_TYPE_24PLUSZ:
		if (tga_bus_pci)
			tga_type_name = "Digital ZLXp-E3";
		if (tga_bus_tc)
			tga_type_name = "Digital ZLX-E3";
		break;
	default:
		tga_type_name = "Unknown";
		break;
	}

	strlcpy(info->fix.id, tga_type_name, sizeof(info->fix.id));

	info->fix.type = FB_TYPE_PACKED_PIXELS;
	info->fix.type_aux = 0;
	info->fix.visual = (tga_type == TGA_TYPE_8PLANE
			    ? FB_VISUAL_PSEUDOCOLOR
			    : FB_VISUAL_DIRECTCOLOR);

	info->fix.line_length = par->xres * (par->bits_per_pixel >> 3);
	info->fix.smem_start = (size_t) par->tga_fb_base;
	info->fix.smem_len = info->fix.line_length * par->yres;
	info->fix.mmio_start = (size_t) par->tga_regs_base;
	info->fix.mmio_len = 512;

	info->fix.xpanstep = 0;
	info->fix.ypanstep = 0;
	info->fix.ywrapstep = 0;

	info->fix.accel = FB_ACCEL_DEC_TGA;

	/*
	 * These are needed by fb_set_logo_truepalette(), so we
	 * set them here for 24-plane cards.
	 */
	if (tga_type != TGA_TYPE_8PLANE) {
		info->var.red.length = 8;
		info->var.green.length = 8;
		info->var.blue.length = 8;
		info->var.red.offset = 16;
		info->var.green.offset = 8;
		info->var.blue.offset = 0;
	}
}

static int tgafb_pan_display(struct fb_var_screeninfo *var, struct fb_info *info)
{
	/* We just use this to catch switches out of graphics mode. */
	tgafb_set_par(info); /* A bit of overkill for BASE_ADDR reset. */
	return 0;
}

static int __devinit
tgafb_register(struct device *dev)
{
	static const struct fb_videomode modedb_tc = {
		/* 1280x1024 @ 72 Hz, 76.8 kHz hsync */
		"1280x1024@72", 0, 1280, 1024, 7645, 224, 28, 33, 3, 160, 3,
		FB_SYNC_ON_GREEN, FB_VMODE_NONINTERLACED
	};

	static unsigned int const fb_offset_presets[4] = {
		TGA_8PLANE_FB_OFFSET,
		TGA_24PLANE_FB_OFFSET,
		0xffffffff,
		TGA_24PLUSZ_FB_OFFSET
	};

	const struct fb_videomode *modedb_tga = NULL;
	resource_size_t bar0_start = 0, bar0_len = 0;
	const char *mode_option_tga = NULL;
	int tga_bus_pci = TGA_BUS_PCI(dev);
	int tga_bus_tc = TGA_BUS_TC(dev);
	unsigned int modedbsize_tga = 0;
	void __iomem *mem_base;
	struct fb_info *info;
	struct tga_par *par;
	u8 tga_type;
	int ret = 0;

	/* Enable device in PCI config.  */
	if (tga_bus_pci && pci_enable_device(to_pci_dev(dev))) {
		printk(KERN_ERR "tgafb: Cannot enable PCI device\n");
		return -ENODEV;
	}

	/* Allocate the fb and par structures.  */
	info = framebuffer_alloc(sizeof(struct tga_par), dev);
	if (!info) {
		printk(KERN_ERR "tgafb: Cannot allocate memory\n");
		return -ENOMEM;
	}

	par = info->par;
	dev_set_drvdata(dev, info);

	/* Request the mem regions.  */
	ret = -ENODEV;
	if (tga_bus_pci) {
		bar0_start = pci_resource_start(to_pci_dev(dev), 0);
		bar0_len = pci_resource_len(to_pci_dev(dev), 0);
	}
	if (tga_bus_tc) {
		bar0_start = to_tc_dev(dev)->resource.start;
		bar0_len = to_tc_dev(dev)->resource.end - bar0_start + 1;
	}
	if (!request_mem_region (bar0_start, bar0_len, "tgafb")) {
		printk(KERN_ERR "tgafb: cannot reserve FB region\n");
		goto err0;
	}

	/* Map the framebuffer.  */
	mem_base = ioremap_nocache(bar0_start, bar0_len);
	if (!mem_base) {
		printk(KERN_ERR "tgafb: Cannot map MMIO\n");
		goto err1;
	}

	/* Grab info about the card.  */
	tga_type = (readl(mem_base) >> 12) & 0x0f;
	par->dev = dev;
	par->tga_mem_base = mem_base;
	par->tga_fb_base = mem_base + fb_offset_presets[tga_type];
	par->tga_regs_base = mem_base + TGA_REGS_OFFSET;
	par->tga_type = tga_type;
	if (tga_bus_pci)
		par->tga_chip_rev = (to_pci_dev(dev))->revision;
	if (tga_bus_tc)
		par->tga_chip_rev = TGA_READ_REG(par, TGA_START_REG) & 0xff;

	/* Setup framebuffer.  */
	info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_COPYAREA |
		      FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT;
	info->fbops = &tgafb_ops;
	info->screen_base = par->tga_fb_base;
	info->pseudo_palette = par->palette;

	/* This should give a reasonable default video mode.  */
	if (tga_bus_pci) {
		mode_option_tga = mode_option_pci;
	}
	if (tga_bus_tc) {
		mode_option_tga = mode_option_tc;
		modedb_tga = &modedb_tc;
		modedbsize_tga = 1;
	}
	ret = fb_find_mode(&info->var, info,
			   mode_option ? mode_option : mode_option_tga,
			   modedb_tga, modedbsize_tga, NULL,
			   tga_type == TGA_TYPE_8PLANE ? 8 : 32);
	if (ret == 0 || ret == 4) {
		printk(KERN_ERR "tgafb: Could not find valid video mode\n");
		ret = -EINVAL;
		goto err1;
	}

	if (fb_alloc_cmap(&info->cmap, 256, 0)) {
		printk(KERN_ERR "tgafb: Could not allocate color map\n");
		ret = -ENOMEM;
		goto err1;
	}

	tgafb_set_par(info);
	tgafb_init_fix(info);

	if (register_framebuffer(info) < 0) {
		printk(KERN_ERR "tgafb: Could not register framebuffer\n");
		ret = -EINVAL;
		goto err1;
	}

	if (tga_bus_pci) {
		pr_info("tgafb: DC21030 [TGA] detected, rev=0x%02x\n",
			par->tga_chip_rev);
		pr_info("tgafb: at PCI bus %d, device %d, function %d\n",
			to_pci_dev(dev)->bus->number,
			PCI_SLOT(to_pci_dev(dev)->devfn),
			PCI_FUNC(to_pci_dev(dev)->devfn));
	}
	if (tga_bus_tc)
		pr_info("tgafb: SFB+ detected, rev=0x%02x\n",
			par->tga_chip_rev);
	pr_info("fb%d: %s frame buffer device at 0x%lx\n",
		info->node, info->fix.id, (long)bar0_start);

	return 0;

 err1:
	if (mem_base)
		iounmap(mem_base);
	release_mem_region(bar0_start, bar0_len);
 err0:
	framebuffer_release(info);
	return ret;
}

static void __devexit
tgafb_unregister(struct device *dev)
{
	resource_size_t bar0_start = 0, bar0_len = 0;
	int tga_bus_pci = TGA_BUS_PCI(dev);
	int tga_bus_tc = TGA_BUS_TC(dev);
	struct fb_info *info = NULL;
	struct tga_par *par;

	info = dev_get_drvdata(dev);
	if (!info)
		return;

	par = info->par;
	unregister_framebuffer(info);
	fb_dealloc_cmap(&info->cmap);
	iounmap(par->tga_mem_base);
	if (tga_bus_pci) {
		bar0_start = pci_resource_start(to_pci_dev(dev), 0);
		bar0_len = pci_resource_len(to_pci_dev(dev), 0);
	}
	if (tga_bus_tc) {
		bar0_start = to_tc_dev(dev)->resource.start;
		bar0_len = to_tc_dev(dev)->resource.end - bar0_start + 1;
	}
	release_mem_region(bar0_start, bar0_len);
	framebuffer_release(info);
}

static void __devexit
tgafb_exit(void)
{
	tc_unregister_driver(&tgafb_tc_driver);
	pci_unregister_driver(&tgafb_pci_driver);
}

#ifndef MODULE
static int __devinit
tgafb_setup(char *arg)
{
	char *this_opt;

	if (arg && *arg) {
		while ((this_opt = strsep(&arg, ","))) {
			if (!*this_opt)
				continue;
			if (!strncmp(this_opt, "mode:", 5))
				mode_option = this_opt+5;
			else
				printk(KERN_ERR
				       "tgafb: unknown parameter %s\n",
				       this_opt);
		}
	}

	return 0;
}
#endif /* !MODULE */

static int __devinit
tgafb_init(void)
{
	int status;
#ifndef MODULE
	char *option = NULL;

	if (fb_get_options("tgafb", &option))
		return -ENODEV;
	tgafb_setup(option);
#endif
	status = pci_register_driver(&tgafb_pci_driver);
	if (!status)
		status = tc_register_driver(&tgafb_tc_driver);
	return status;
}

/*
 *  Modularisation
 */

module_init(tgafb_init);
module_exit(tgafb_exit);

MODULE_DESCRIPTION("Framebuffer driver for TGA/SFB+ chipset");
MODULE_LICENSE("GPL");