/* * AGPGART driver backend routines. * Copyright (C) 2004 Silicon Graphics, Inc. * Copyright (C) 2002-2003 Dave Jones. * Copyright (C) 1999 Jeff Hartmann. * Copyright (C) 1999 Precision Insight, Inc. * Copyright (C) 1999 Xi Graphics, Inc. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL * JEFF HARTMANN, DAVE JONES, OR ANY OTHER CONTRIBUTORS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * TODO: * - Allocate more than order 0 pages to avoid too much linear map splitting. */#include <linux/module.h>#include <linux/pci.h>#include <linux/init.h>#include <linux/pagemap.h>#include <linux/miscdevice.h>#include <linux/pm.h>#include <linux/agp_backend.h>#include <linux/agpgart.h>#include <linux/vmalloc.h>#include <asm/io.h>#include "agp.h"/* Due to XFree86 brain-damage, we can't go to 1.0 until they * fix some real stupidity. It's only by chance we can bump * past 0.99 at all due to some boolean logic error. */#define AGPGART_VERSION_MAJOR 0#define AGPGART_VERSION_MINOR 101static struct agp_version agp_current_version ={	.major = AGPGART_VERSION_MAJOR,	.minor = AGPGART_VERSION_MINOR,};struct agp_bridge_data *(*agp_find_bridge)(struct pci_dev *) =	&agp_generic_find_bridge;struct agp_bridge_data *agp_bridge;LIST_HEAD(agp_bridges);EXPORT_SYMBOL(agp_bridge);EXPORT_SYMBOL(agp_bridges);EXPORT_SYMBOL(agp_find_bridge);/** *	agp_backend_acquire  -  attempt to acquire an agp backend. * */struct agp_bridge_data *agp_backend_acquire(struct pci_dev *pdev){	struct agp_bridge_data *bridge;	bridge = agp_find_bridge(pdev);	if (!bridge)		return NULL;	if (atomic_read(&bridge->agp_in_use))		return NULL;	atomic_inc(&bridge->agp_in_use);	return bridge;}EXPORT_SYMBOL(agp_backend_acquire);/** *	agp_backend_release  -  release the lock on the agp backend. * *	The caller must insure that the graphics aperture translation table *	is read for use by another entity. * *	(Ensure that all memory it bound is unbound.) */void agp_backend_release(struct agp_bridge_data *bridge){	if (bridge)		atomic_dec(&bridge->agp_in_use);}EXPORT_SYMBOL(agp_backend_release);static const struct { int mem, agp; } maxes_table[] = {	{0, 0},	{32, 4},	{64, 28},	{128, 96},	{256, 204},	{512, 440},	{1024, 942},	{2048, 1920},	{4096, 3932}};static int agp_find_max(void){	long memory, index, result;#if PAGE_SHIFT < 20	memory = num_physpages >> (20 - PAGE_SHIFT);#else	memory = num_physpages << (PAGE_SHIFT - 20);#endif	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);	result = result << (20 - PAGE_SHIFT);	return result;}static int agp_backend_initialize(struct agp_bridge_data *bridge){	int size_value, rc, got_gatt=0, got_keylist=0;	bridge->max_memory_agp = agp_find_max();	bridge->version = &agp_current_version;	if (bridge->driver->needs_scratch_page) {		void *addr = bridge->driver->agp_alloc_page(bridge);		if (!addr) {			printk(KERN_ERR PFX "unable to get memory for scratch page.\n");			return -ENOMEM;		}		flush_agp_mappings();		bridge->scratch_page_real = virt_to_gart(addr);		bridge->scratch_page =		    bridge->driver->mask_memory(bridge, bridge->scratch_page_real, 0);	}	size_value = bridge->driver->fetch_size();	if (size_value == 0) {		printk(KERN_ERR PFX "unable to determine aperture size.\n");		rc = -EINVAL;		goto err_out;	}	if (bridge->driver->create_gatt_table(bridge)) {		printk(KERN_ERR PFX		    "unable to get memory for graphics translation table.\n");		rc = -ENOMEM;		goto err_out;	}	got_gatt = 1;	bridge->key_list = vmalloc(PAGE_SIZE * 4);	if (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(bridge->key_list, 0, PAGE_SIZE * 4);	if (bridge->driver->configure()) {		printk(KERN_ERR PFX "error configuring host chipset.\n");		rc = -EINVAL;		goto err_out;	}	return 0;err_out:	if (bridge->driver->needs_scratch_page) {		bridge->driver->agp_destroy_page(				gart_to_virt(bridge->scratch_page_real));		flush_agp_mappings();	}	if (got_gatt)		bridge->driver->free_gatt_table(bridge);	if (got_keylist) {		vfree(bridge->key_list);		bridge->key_list = NULL;	}	return rc;}/* cannot be __exit b/c as it could be called from __init code */static void agp_backend_cleanup(struct agp_bridge_data *bridge){	if (bridge->driver->cleanup)		bridge->driver->cleanup();	if (bridge->driver->free_gatt_table)		bridge->driver->free_gatt_table(bridge);	vfree(bridge->key_list);	bridge->key_list = NULL;	if (bridge->driver->agp_destroy_page &&	    bridge->driver->needs_scratch_page) {		bridge->driver->agp_destroy_page(				gart_to_virt(bridge->scratch_page_real));		flush_agp_mappings();	}}/* When we remove the global variable agp_bridge from all drivers * then agp_alloc_bridge and agp_generic_find_bridge need to be updated */struct agp_bridge_data *agp_alloc_bridge(void){	struct agp_bridge_data *bridge;	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);	if (!bridge)		return NULL;	atomic_set(&bridge->agp_in_use, 0);	atomic_set(&bridge->current_memory_agp, 0);	if (list_empty(&agp_bridges))		agp_bridge = bridge;	return bridge;}EXPORT_SYMBOL(agp_alloc_bridge);void agp_put_bridge(struct agp_bridge_data *bridge){        kfree(bridge);        if (list_empty(&agp_bridges))                agp_bridge = NULL;}EXPORT_SYMBOL(agp_put_bridge);int agp_add_bridge(struct agp_bridge_data *bridge){	int error;	if (agp_off)		return -ENODEV;	if (!bridge->dev) {		printk (KERN_DEBUG PFX "Erk, registering with no pci_dev!\n");		return -EINVAL;	}	/* Grab reference on the chipset driver. */	if (!try_module_get(bridge->driver->owner)) {		printk (KERN_INFO PFX "Couldn't lock chipset driver.\n");		return -EINVAL;	}	error = agp_backend_initialize(bridge);	if (error) {		printk (KERN_INFO PFX "agp_backend_initialize() failed.\n");		goto err_out;	}	if (list_empty(&agp_bridges)) {		error = agp_frontend_initialize();		if (error) {			printk (KERN_INFO PFX "agp_frontend_initialize() failed.\n");			goto frontend_err;		}		printk(KERN_INFO PFX "AGP aperture is %dM @ 0x%lx\n",			bridge->driver->fetch_size(), bridge->gart_bus_addr);	}	list_add(&bridge->list, &agp_bridges);	return 0;frontend_err:	agp_backend_cleanup(bridge);err_out:	module_put(bridge->driver->owner);	agp_put_bridge(bridge);	return error;}EXPORT_SYMBOL_GPL(agp_add_bridge);void agp_remove_bridge(struct agp_bridge_data *bridge){	agp_backend_cleanup(bridge);	list_del(&bridge->list);	if (list_empty(&agp_bridges))		agp_frontend_cleanup();	module_put(bridge->driver->owner);}EXPORT_SYMBOL_GPL(agp_remove_bridge);int agp_off;int agp_try_unsupported_boot;EXPORT_SYMBOL(agp_off);EXPORT_SYMBOL(agp_try_unsupported_boot);static int __init agp_init(void){	if (!agp_off)		printk(KERN_INFO "Linux agpgart interface v%d.%d (c) Dave Jones\n",			AGPGART_VERSION_MAJOR, AGPGART_VERSION_MINOR);	return 0;}static void __exit agp_exit(void){}#ifndef MODULEstatic __init int agp_setup(char *s){	if (!strcmp(s,"off"))		agp_off = 1;	if (!strcmp(s,"try_unsupported"))		agp_try_unsupported_boot = 1;	return 1;}__setup("agp=", agp_setup);#endifMODULE_AUTHOR("Dave Jones <davej@codemonkey.org.uk>");MODULE_DESCRIPTION("AGP GART driver");MODULE_LICENSE("GPL and additional rights");MODULE_ALIAS_MISCDEV(AGPGART_MINOR);module_init(agp_init);module_exit(agp_exit);