agpgart_be.c

讲述linux的初始化过程

		PCI_VENDOR_ID_AMD,
		AMD_IRONGATE,
		"AMD",
		"Irongate",
		amd_irongate_setup },
	{ 0,
		PCI_VENDOR_ID_AMD,
		AMD_GENERIC,
		"AMD",
		"Generic",
		amd_irongate_setup },
#endif /* CONFIG_AGP_AMD */

#ifdef CONFIG_AGP_INTEL
	{ PCI_DEVICE_ID_INTEL_82443LX_0,
		PCI_VENDOR_ID_INTEL,
		INTEL_LX,
		"Intel",
		"440LX",
		intel_generic_setup },
	{ PCI_DEVICE_ID_INTEL_82443BX_0,
		PCI_VENDOR_ID_INTEL,
		INTEL_BX,
		"Intel",
		"440BX",
		intel_generic_setup },
	{ PCI_DEVICE_ID_INTEL_82443GX_0,
		PCI_VENDOR_ID_INTEL,
		INTEL_GX,
		"Intel",
		"440GX",
		intel_generic_setup },
	/* could we add support for PCI_DEVICE_ID_INTEL_815_1 too ? */
	{ PCI_DEVICE_ID_INTEL_815_0,
		PCI_VENDOR_ID_INTEL,
		INTEL_I815,
		"Intel",
		"i815",
		intel_generic_setup },
	{ PCI_DEVICE_ID_INTEL_840_0,
		PCI_VENDOR_ID_INTEL,
		INTEL_I840,
		"Intel",
		"i840",
		intel_840_setup },
	{ PCI_DEVICE_ID_INTEL_850_0,
	        PCI_VENDOR_ID_INTEL,
	        INTEL_I850,
	        "Intel",
	        "i850",
	        intel_850_setup },
	{ 0,
		PCI_VENDOR_ID_INTEL,
		INTEL_GENERIC,
		"Intel",
		"Generic",
		intel_generic_setup },
#endif /* CONFIG_AGP_INTEL */

#ifdef CONFIG_AGP_SIS
	{ PCI_DEVICE_ID_SI_630,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"630",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_540,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"540",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_620,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"620",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_530,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"530",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_630,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"Generic",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_540,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"Generic",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_620,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"Generic",
		sis_generic_setup },
	{ PCI_DEVICE_ID_SI_530,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"Generic",
		sis_generic_setup },
	{ 0,
		PCI_VENDOR_ID_SI,
		SIS_GENERIC,
		"SiS",
		"Generic",
		sis_generic_setup },
#endif /* CONFIG_AGP_SIS */

#ifdef CONFIG_AGP_VIA
	{ PCI_DEVICE_ID_VIA_8501_0,
		PCI_VENDOR_ID_VIA,
		VIA_MVP4,
		"Via",
		"MVP4",
		via_generic_setup },
	{ PCI_DEVICE_ID_VIA_82C597_0,
		PCI_VENDOR_ID_VIA,
		VIA_VP3,
		"Via",
		"VP3",
		via_generic_setup },
	{ PCI_DEVICE_ID_VIA_82C598_0,
		PCI_VENDOR_ID_VIA,
		VIA_MVP3,
		"Via",
		"MVP3",
		via_generic_setup },
	{ PCI_DEVICE_ID_VIA_82C691_0,
		PCI_VENDOR_ID_VIA,
		VIA_APOLLO_PRO,
		"Via",
		"Apollo Pro",
		via_generic_setup },
	{ PCI_DEVICE_ID_VIA_8371_0,
		PCI_VENDOR_ID_VIA,
		VIA_APOLLO_KX133,
		"Via",
		"Apollo Pro KX133",
		via_generic_setup },
	{ PCI_DEVICE_ID_VIA_8363_0,
		PCI_VENDOR_ID_VIA,
		VIA_APOLLO_KT133,
		"Via",
		"Apollo Pro KT133",
		via_generic_setup },
	{ 0,
		PCI_VENDOR_ID_VIA,
		VIA_GENERIC,
		"Via",
		"Generic",
		via_generic_setup },
#endif /* CONFIG_AGP_VIA */

	{ 0, }, /* dummy final entry, always present */
};


/* scan table above for supported devices */
static int __init agp_lookup_host_bridge (struct pci_dev *pdev)
{
	int i;
	
	for (i = 0; i < ARRAY_SIZE (agp_bridge_info); i++)
		if (pdev->vendor == agp_bridge_info[i].vendor_id)
			break;

	if (i >= ARRAY_SIZE (agp_bridge_info)) {
		printk (KERN_DEBUG PFX "unsupported bridge\n");
		return -ENODEV;
	}

	while ((i < ARRAY_SIZE (agp_bridge_info)) &&
	       (agp_bridge_info[i].vendor_id == pdev->vendor)) {
		if (pdev->device == agp_bridge_info[i].device_id) {
			printk (KERN_INFO PFX "Detected %s %s chipset\n",
				agp_bridge_info[i].vendor_name,
				agp_bridge_info[i].chipset_name);
			agp_bridge.type = agp_bridge_info[i].chipset;
			return agp_bridge_info[i].chipset_setup (pdev);
		}
		
		i++;
	}

	i--; /* point to vendor generic entry (device_id == 0) */

	/* try init anyway, if user requests it AND
	 * there is a 'generic' bridge entry for this vendor */
	if (agp_try_unsupported && agp_bridge_info[i].device_id == 0) {
		printk(KERN_WARNING PFX "Trying generic %s routines"
		       " for device id: %04x\n",
		       agp_bridge_info[i].vendor_name, pdev->device);
		agp_bridge.type = agp_bridge_info[i].chipset;
		return agp_bridge_info[i].chipset_setup (pdev);
	}

	printk(KERN_ERR PFX "Unsupported %s chipset (device id: %04x),"
	       " you might want to try agp_try_unsupported=1.\n",
	       agp_bridge_info[i].vendor_name, pdev->device);
	return -ENODEV;
}


/* Supported Device Scanning routine */

static int __init agp_find_supported_device(void)
{
	struct pci_dev *dev = NULL;
	u8 cap_ptr = 0x00;
	u32 cap_id, scratch;

	if ((dev = pci_find_class(PCI_CLASS_BRIDGE_HOST << 8, NULL)) == NULL)
		return -ENODEV;

	agp_bridge.dev = dev;

	/* Need to test for I810 here */
#ifdef CONFIG_AGP_I810
	if (dev->vendor == PCI_VENDOR_ID_INTEL) {
		struct pci_dev *i810_dev;

		switch (dev->device) {
		case PCI_DEVICE_ID_INTEL_810_0:
			i810_dev = pci_find_device(PCI_VENDOR_ID_INTEL,
					       PCI_DEVICE_ID_INTEL_810_1,
						   NULL);
			if (i810_dev == NULL) {
				printk(KERN_ERR PFX "Detected an Intel i810,"
				       " but could not find the secondary"
				       " device.\n");
				return -ENODEV;
			}
			printk(KERN_INFO PFX "Detected an Intel "
			       "i810 Chipset.\n");
			agp_bridge.type = INTEL_I810;
			return intel_i810_setup (i810_dev);

		case PCI_DEVICE_ID_INTEL_810_DC100_0:
			i810_dev = pci_find_device(PCI_VENDOR_ID_INTEL,
					 PCI_DEVICE_ID_INTEL_810_DC100_1,
						   NULL);
			if (i810_dev == NULL) {
				printk(KERN_ERR PFX "Detected an Intel i810 "
				       "DC100, but could not find the "
				       "secondary device.\n");
				return -ENODEV;
			}
			printk(KERN_INFO PFX "Detected an Intel i810 "
			       "DC100 Chipset.\n");
			agp_bridge.type = INTEL_I810;
			return intel_i810_setup(i810_dev);

		case PCI_DEVICE_ID_INTEL_810_E_0:
			i810_dev = pci_find_device(PCI_VENDOR_ID_INTEL,
					     PCI_DEVICE_ID_INTEL_810_E_1,
						   NULL);
			if (i810_dev == NULL) {
				printk(KERN_ERR PFX "Detected an Intel i810 E"
				    ", but could not find the secondary "
				       "device.\n");
				return -ENODEV;
			}
			printk(KERN_INFO PFX "Detected an Intel i810 E "
			       "Chipset.\n");
			agp_bridge.type = INTEL_I810;
			return intel_i810_setup(i810_dev);

		 case PCI_DEVICE_ID_INTEL_815_0:
		   /* The i815 can operate either as an i810 style
		    * integrated device, or as an AGP4X motherboard.
		    *
		    * This only addresses the first mode:
		    */
			i810_dev = pci_find_device(PCI_VENDOR_ID_INTEL,
						   PCI_DEVICE_ID_INTEL_815_1,
						   NULL);
			if (i810_dev == NULL) {
				printk(KERN_ERR PFX "agpgart: Detected an "
				       "Intel i815, but could not find the"
				       " secondary device.\n");
				agp_bridge.type = NOT_SUPPORTED;
				return -ENODEV;
			}
			printk(KERN_INFO PFX "agpgart: Detected an Intel i815 "
			       "Chipset.\n");
			agp_bridge.type = INTEL_I810;
			return intel_i810_setup(i810_dev);

		default:
			break;
		}
	}
#endif /* CONFIG_AGP_I810 */

	/* find capndx */
	pci_read_config_dword(dev, 0x04, &scratch);
	if (!(scratch & 0x00100000))
		return -ENODEV;

	pci_read_config_byte(dev, 0x34, &cap_ptr);
	if (cap_ptr != 0x00) {
		do {
			pci_read_config_dword(dev, cap_ptr, &cap_id);

			if ((cap_id & 0xff) != 0x02)
				cap_ptr = (cap_id >> 8) & 0xff;
		}
		while (((cap_id & 0xff) != 0x02) && (cap_ptr != 0x00));
	}
	if (cap_ptr == 0x00)
		return -ENODEV;
	agp_bridge.capndx = cap_ptr;

	/* Fill in the mode register */
	pci_read_config_dword(agp_bridge.dev,
			      agp_bridge.capndx + 4,
			      &agp_bridge.mode);

	/* probe for known chipsets */
	return agp_lookup_host_bridge (dev);
}

struct agp_max_table {
	int mem;
	int agp;
};

static struct agp_max_table maxes_table[9] __initdata =
{
	{0, 0},
	{32, 4},
	{64, 28},
	{128, 96},
	{256, 204},
	{512, 440},
	{1024, 942},
	{2048, 1920},
	{4096, 3932}
};

static int __init agp_find_max (void)
{
	long memory, index, result;

	memory = virt_to_phys(high_memory) >> 20;
	index = 1;

	while ((memory > maxes_table[index].mem) &&
	       (index < 8)) {
		index++;
	}

	result = maxes_table[index - 1].agp +
	   ( (memory - maxes_table[index - 1].mem)  *
	     (maxes_table[index].agp - maxes_table[index - 1].agp)) /
	   (maxes_table[index].mem - maxes_table[index - 1].mem);

	printk(KERN_INFO PFX "Maximum main memory to use "
	       "for agp memory: %ldM\n", result);
	result = result << (20 - PAGE_SHIFT);
        return result;
}

#define AGPGART_VERSION_MAJOR 0
#define AGPGART_VERSION_MINOR 99

static agp_version agp_current_version =
{
	AGPGART_VERSION_MAJOR,
	AGPGART_VERSION_MINOR
};

static int __init agp_backend_initialize(void)
{
	int size_value, rc, got_gatt=0, got_keylist=0;

	memset(&agp_bridge, 0, sizeof(struct agp_bridge_data));
	agp_bridge.type = NOT_SUPPORTED;
	agp_bridge.max_memory_agp = agp_find_max();
	agp_bridge.version = &agp_current_version;

	rc = agp_find_supported_device();
	if (rc) {
		/* not KERN_ERR because error msg should have already printed */
		printk(KERN_DEBUG PFX "no supported devices found.\n");
		return rc;
	}

	if (agp_bridge.needs_scratch_page == TRUE) {
		agp_bridge.scratch_page = agp_alloc_page();

		if (agp_bridge.scratch_page == 0) {
			printk(KERN_ERR PFX "unable to get memory for "
			       "scratch page.\n");
			return -ENOMEM;
		}
		agp_bridge.scratch_page =
		    virt_to_phys((void *) agp_bridge.scratch_page);
		agp_bridge.scratch_page =
		    agp_bridge.mask_memory(agp_bridge.scratch_page, 0);
	}

	size_value = agp_bridge.fetch_size();

	if (size_value == 0) {
		printk(KERN_ERR PFX "unable to detrimine aperture size.\n");
		rc = -EINVAL;
		goto err_out;
	}
	if (agp_bridge.create_gatt_table()) {
		printk(KERN_ERR PFX "unable to get memory for graphics "
		       "translation table.\n");
		rc = -ENOMEM;
		goto err_out;
	}
	got_gatt = 1;
	
	agp_bridge.key_list = vmalloc(PAGE_SIZE * 4);
	if (agp_bridge.key_list == NULL) {
		printk(KERN_ERR PFX "error allocating memory for key lists.\n");
		rc = -ENOMEM;
		goto err_out;
	}
	got_keylist = 1;
	
	/* FIXME vmalloc'd memory not guaranteed contiguous */
	memset(agp_bridge.key_list, 0, PAGE_SIZE * 4);

	if (agp_bridge.configure()) {
		printk(KERN_ERR PFX "error configuring host chipset.\n");
		rc = -EINVAL;
		goto err_out;
	}

	printk(KERN_INFO PFX "AGP aperture is %dM @ 0x%lx\n",
	       size_value, agp_bridge.gart_bus_addr);

	return 0;

err_out:
	if (agp_bridge.needs_scratch_page == TRUE) {
		agp_bridge.scratch_page &= ~(0x00000fff);
		agp_destroy_page((unsigned long)
				 phys_to_virt(agp_bridge.scratch_page));
	}
	if (got_gatt)
		agp_bridge.free_gatt_table();
	if (got_keylist)
		vfree(agp_bridge.key_list);
	return rc;
}


/* cannot be __exit b/c as it could be called from __init code */
static void agp_backend_cleanup(void)
{
	agp_bridge.cleanup();
	agp_bridge.free_gatt_table();
	vfree(agp_bridge.key_list);

	if (agp_bridge.needs_scratch_page == TRUE) {
		agp_bridge.scratch_page &= ~(0x00000fff);
		agp_destroy_page((unsigned long)
				 phys_to_virt(agp_bridge.scratch_page));
	}
}

extern int agp_frontend_initialize(void);
extern void agp_frontend_cleanup(void);

static const drm_agp_t drm_agp = {
	&agp_free_memory,
	&agp_allocate_memory,
	&agp_bind_memory,
	&agp_unbind_memory,
	&agp_enable,
	&agp_backend_acquire,
	&agp_backend_release,
	&agp_copy_info
};

static int __init agp_init(void)
{
	int ret_val;

	printk(KERN_INFO "Linux agpgart interface v%d.%d (c) Jeff Hartmann\n",
	       AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);

	ret_val = agp_backend_initialize();
	if (ret_val) {
		agp_bridge.type = NOT_SUPPORTED;
		return ret_val;
	}
	ret_val = agp_frontend_initialize();
	if (ret_val) {
		agp_bridge.type = NOT_SUPPORTED;
		agp_backend_cleanup();
		return ret_val;
	}

	inter_module_register("drm_agp", THIS_MODULE, &drm_agp);
	return 0;
}

static void __exit agp_cleanup(void)
{
	agp_frontend_cleanup();
	agp_backend_cleanup();
	inter_module_unregister("drm_agp");
}

module_init(agp_init);
module_exit(agp_cleanup);