platinumfb.c

Linux环境下视频显示卡设备的驱动程序源代码

		default_vmode = VMODE_640_480_60;
#ifdef CONFIG_NVRAM
	if (default_cmode == CMODE_NVRAM)
		default_cmode = nvram_read_byte(NV_CMODE);
#endif
	if (default_cmode < CMODE_8 || default_cmode > CMODE_32)
		default_cmode = CMODE_8;
	/*
	 * Reduce the pixel size if we don't have enough VRAM.
	 */
	while(default_cmode > CMODE_8 &&
	      platinum_vram_reqd(default_vmode, default_cmode) > pinfo->total_vram)
		default_cmode--;

	printk("platinumfb:  Using video mode %d and color mode %d.\n", default_vmode, default_cmode);

	/* Setup default var */
	if (mac_vmode_to_var(default_vmode, default_cmode, &var) < 0) {
		/* This shouldn't happen! */
		printk("mac_vmode_to_var(%d, %d,) failed\n", default_vmode, default_cmode);
try_again:
		default_vmode = VMODE_640_480_60;
		default_cmode = CMODE_8;
		if (mac_vmode_to_var(default_vmode, default_cmode, &var) < 0) {
			printk(KERN_ERR "platinumfb: mac_vmode_to_var() failed\n");
			return -ENXIO;
		}
	}

	/* Initialize info structure */
	platinum_init_info(info, pinfo);

	/* Apply default var */
	info->var = var;
	var.activate = FB_ACTIVATE_NOW;
	rc = fb_set_var(info, &var);
	if (rc && (default_vmode != VMODE_640_480_60 || default_cmode != CMODE_8))
		goto try_again;

	/* Register with fbdev layer */
	rc = register_framebuffer(info);
	if (rc < 0)
		return rc;

	printk(KERN_INFO "fb%d: Apple Platinum frame buffer device\n", info->node);

	return 0;
}

/*
 * Get the monitor sense value.
 * Note that this can be called before calibrate_delay,
 * so we can't use udelay.
 */
static int read_platinum_sense(struct fb_info_platinum *info)
{
	volatile struct platinum_regs __iomem *platinum_regs = info->platinum_regs;
	int sense;

	out_be32(&platinum_regs->reg[23].r, 7);	/* turn off drivers */
	__delay(2000);
	sense = (~in_be32(&platinum_regs->reg[23].r) & 7) << 8;

	/* drive each sense line low in turn and collect the other 2 */
	out_be32(&platinum_regs->reg[23].r, 3);	/* drive A low */
	__delay(2000);
	sense |= (~in_be32(&platinum_regs->reg[23].r) & 3) << 4;
	out_be32(&platinum_regs->reg[23].r, 5);	/* drive B low */
	__delay(2000);
	sense |= (~in_be32(&platinum_regs->reg[23].r) & 4) << 1;
	sense |= (~in_be32(&platinum_regs->reg[23].r) & 1) << 2;
	out_be32(&platinum_regs->reg[23].r, 6);	/* drive C low */
	__delay(2000);
	sense |= (~in_be32(&platinum_regs->reg[23].r) & 6) >> 1;

	out_be32(&platinum_regs->reg[23].r, 7);	/* turn off drivers */

	return sense;
}

/*
 * This routine takes a user-supplied var, and picks the best vmode/cmode from it.
 * It also updates the var structure to the actual mode data obtained
 */
static int platinum_var_to_par(struct fb_var_screeninfo *var, 
			       struct fb_info_platinum *pinfo,
			       int check_only)
{
	int vmode, cmode;

	if (mac_var_to_vmode(var, &vmode, &cmode) != 0) {
		printk(KERN_ERR "platinum_var_to_par: mac_var_to_vmode unsuccessful.\n");
		printk(KERN_ERR "platinum_var_to_par: var->xres = %d\n", var->xres);
		printk(KERN_ERR "platinum_var_to_par: var->yres = %d\n", var->yres);
		printk(KERN_ERR "platinum_var_to_par: var->xres_virtual = %d\n", var->xres_virtual);
		printk(KERN_ERR "platinum_var_to_par: var->yres_virtual = %d\n", var->yres_virtual);
		printk(KERN_ERR "platinum_var_to_par: var->bits_per_pixel = %d\n", var->bits_per_pixel);
		printk(KERN_ERR "platinum_var_to_par: var->pixclock = %d\n", var->pixclock);
		printk(KERN_ERR "platinum_var_to_par: var->vmode = %d\n", var->vmode);
		return -EINVAL;
	}

	if (!platinum_reg_init[vmode-1]) {
		printk(KERN_ERR "platinum_var_to_par, vmode %d not valid.\n", vmode);
		return -EINVAL;
	}

	if (platinum_vram_reqd(vmode, cmode) > pinfo->total_vram) {
		printk(KERN_ERR "platinum_var_to_par, not enough ram for vmode %d, cmode %d.\n", vmode, cmode);
		return -EINVAL;
	}

	if (mac_vmode_to_var(vmode, cmode, var))
		return -EINVAL;

	if (check_only)
		return 0;

	pinfo->vmode = vmode;
	pinfo->cmode = cmode;
	pinfo->xres = vmode_attrs[vmode-1].hres;
	pinfo->yres = vmode_attrs[vmode-1].vres;
	pinfo->xoffset = 0;
	pinfo->yoffset = 0;
	pinfo->vxres = pinfo->xres;
	pinfo->vyres = pinfo->yres;
	
	return 0;
}


/* 
 * Parse user speficied options (`video=platinumfb:')
 */
static int __init platinumfb_setup(char *options)
{
	char *this_opt;

	if (!options || !*options)
		return 0;

	while ((this_opt = strsep(&options, ",")) != NULL) {
		if (!strncmp(this_opt, "vmode:", 6)) {
	    		int vmode = simple_strtoul(this_opt+6, NULL, 0);
			if (vmode > 0 && vmode <= VMODE_MAX)
				default_vmode = vmode;
		} else if (!strncmp(this_opt, "cmode:", 6)) {
			int depth = simple_strtoul(this_opt+6, NULL, 0);
			switch (depth) {
			 case 0:
			 case 8:
			    default_cmode = CMODE_8;
			    break;
			 case 15:
			 case 16:
			    default_cmode = CMODE_16;
			    break;
			 case 24:
			 case 32:
			    default_cmode = CMODE_32;
			    break;
			}
		}
	}
	return 0;
}

#ifdef __powerpc__
#define invalidate_cache(addr) \
	asm volatile("eieio; dcbf 0,%1" \
	: "=m" (*(addr)) : "r" (addr) : "memory");
#else
#define invalidate_cache(addr)
#endif

static int __devinit platinumfb_probe(struct of_device* odev,
				      const struct of_device_id *match)
{
	struct device_node	*dp = odev->node;
	struct fb_info		*info;
	struct fb_info_platinum	*pinfo;
	volatile __u8		*fbuffer;
	int			bank0, bank1, bank2, bank3, rc;

	dev_info(&odev->dev, "Found Apple Platinum video hardware\n");

	info = framebuffer_alloc(sizeof(*pinfo), &odev->dev);
	if (info == NULL) {
		dev_err(&odev->dev, "Failed to allocate fbdev !\n");
		return -ENOMEM;
	}
	pinfo = info->par;

	if (of_address_to_resource(dp, 0, &pinfo->rsrc_reg) ||
	    of_address_to_resource(dp, 1, &pinfo->rsrc_fb)) {
		dev_err(&odev->dev, "Can't get resources\n");
		framebuffer_release(info);
		return -ENXIO;
	}
	dev_dbg(&odev->dev, " registers  : 0x%llx...0x%llx\n",
		(unsigned long long)pinfo->rsrc_reg.start,
		(unsigned long long)pinfo->rsrc_reg.end);
	dev_dbg(&odev->dev, " framebuffer: 0x%llx...0x%llx\n",
		(unsigned long long)pinfo->rsrc_fb.start,
		(unsigned long long)pinfo->rsrc_fb.end);

	/* Do not try to request register space, they overlap with the
	 * northbridge and that can fail. Only request framebuffer
	 */
	if (!request_mem_region(pinfo->rsrc_fb.start,
				pinfo->rsrc_fb.end - pinfo->rsrc_fb.start + 1,
				"platinumfb framebuffer")) {
		printk(KERN_ERR "platinumfb: Can't request framebuffer !\n");
		framebuffer_release(info);
		return -ENXIO;
	}

	/* frame buffer - map only 4MB */
	pinfo->frame_buffer_phys = pinfo->rsrc_fb.start;
	pinfo->frame_buffer = __ioremap(pinfo->rsrc_fb.start, 0x400000,
					_PAGE_WRITETHRU);
	pinfo->base_frame_buffer = pinfo->frame_buffer;

	/* registers */
	pinfo->platinum_regs_phys = pinfo->rsrc_reg.start;
	pinfo->platinum_regs = ioremap(pinfo->rsrc_reg.start, 0x1000);

	pinfo->cmap_regs_phys = 0xf301b000;	/* XXX not in prom? */
	request_mem_region(pinfo->cmap_regs_phys, 0x1000, "platinumfb cmap");
	pinfo->cmap_regs = ioremap(pinfo->cmap_regs_phys, 0x1000);

	/* Grok total video ram */
	out_be32(&pinfo->platinum_regs->reg[16].r, (unsigned)pinfo->frame_buffer_phys);
	out_be32(&pinfo->platinum_regs->reg[20].r, 0x1011);	/* select max vram */
	out_be32(&pinfo->platinum_regs->reg[24].r, 0);	/* switch in vram */

	fbuffer = pinfo->base_frame_buffer;
	fbuffer[0x100000] = 0x34;
	fbuffer[0x100008] = 0x0;
	invalidate_cache(&fbuffer[0x100000]);
	fbuffer[0x200000] = 0x56;
	fbuffer[0x200008] = 0x0;
	invalidate_cache(&fbuffer[0x200000]);
	fbuffer[0x300000] = 0x78;
	fbuffer[0x300008] = 0x0;
	invalidate_cache(&fbuffer[0x300000]);
	bank0 = 1; /* builtin 1MB vram, always there */
	bank1 = fbuffer[0x100000] == 0x34;
	bank2 = fbuffer[0x200000] == 0x56;
	bank3 = fbuffer[0x300000] == 0x78;
	pinfo->total_vram = (bank0 + bank1 + bank2 + bank3) * 0x100000;
	printk(KERN_INFO "platinumfb: Total VRAM = %dMB (%d%d%d%d)\n",
	       (unsigned int) (pinfo->total_vram / 1024 / 1024),
	       bank3, bank2, bank1, bank0);

	/*
	 * Try to determine whether we have an old or a new DACula.
	 */
	out_8(&pinfo->cmap_regs->addr, 0x40);
	pinfo->dactype = in_8(&pinfo->cmap_regs->d2);
	switch (pinfo->dactype) {
	case 0x3c:
		pinfo->clktype = 1;
		printk(KERN_INFO "platinumfb: DACula type 0x3c\n");
		break;
	case 0x84:
		pinfo->clktype = 0;
		printk(KERN_INFO "platinumfb: DACula type 0x84\n");
		break;
	default:
		pinfo->clktype = 0;
		printk(KERN_INFO "platinumfb: Unknown DACula type: %x\n", pinfo->dactype);
		break;
	}
	dev_set_drvdata(&odev->dev, info);
	
	rc = platinum_init_fb(info);
	if (rc != 0) {
		iounmap(pinfo->frame_buffer);
		iounmap(pinfo->platinum_regs);
		iounmap(pinfo->cmap_regs);
		dev_set_drvdata(&odev->dev, NULL);
		framebuffer_release(info);
	}

	return rc;
}

static int __devexit platinumfb_remove(struct of_device* odev)
{
	struct fb_info		*info = dev_get_drvdata(&odev->dev);
	struct fb_info_platinum	*pinfo = info->par;
	
        unregister_framebuffer (info);
	
	/* Unmap frame buffer and registers */
	iounmap(pinfo->frame_buffer);
	iounmap(pinfo->platinum_regs);
	iounmap(pinfo->cmap_regs);

	release_mem_region(pinfo->rsrc_fb.start,
			   pinfo->rsrc_fb.end -
			   pinfo->rsrc_fb.start + 1);

	release_mem_region(pinfo->cmap_regs_phys, 0x1000);

	framebuffer_release(info);

	return 0;
}

static struct of_device_id platinumfb_match[] = 
{
	{
	.name 		= "platinum",
	},
	{},
};

static struct of_platform_driver platinum_driver = 
{
	.name 		= "platinumfb",
	.match_table	= platinumfb_match,
	.probe		= platinumfb_probe,
	.remove		= platinumfb_remove,
};

static int __init platinumfb_init(void)
{
#ifndef MODULE
	char *option = NULL;

	if (fb_get_options("platinumfb", &option))
		return -ENODEV;
	platinumfb_setup(option);
#endif
	of_register_platform_driver(&platinum_driver);

	return 0;
}

static void __exit platinumfb_exit(void)
{
	of_unregister_platform_driver(&platinum_driver);
}

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("framebuffer driver for Apple Platinum video");
module_init(platinumfb_init);

#ifdef MODULE
module_exit(platinumfb_exit);
#endif