agpgart_be.c

/*
 * AGPGART module version 2.0
 * Copyright (C) 2003 Tungsten Graphics
 * Copyright (C) 2003 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, 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.
 *
 */
#include <linux/config.h>
#include <linux/version.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/miscdevice.h>
#include <linux/pm.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/page.h>

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 5, 0)
#include <asm/tlbflush.h>
#endif

#include <linux/agp_backend.h>
#include "agp.h"

MODULE_AUTHOR("Jeff Hartmann <jhartmann@addoes.com>");
MODULE_PARM(agp_try_unsupported, "1i");
MODULE_LICENSE("Dual BSD/GPL");

EXPORT_SYMBOL(agp_backend_acquire);
EXPORT_SYMBOL(agp_backend_release);

static __inline__ void flush_cache(void)
{
#if defined(__i386__) || defined(__x86_64__)
	asm volatile ("wbinvd":::"memory");
#elif defined(__alpha__) || defined(__ia64__) || defined(__sparc__)
	/* ??? I wonder if we'll really need to flush caches, or if the
	   core logic can manage to keep the system coherent.  The ARM
	   speaks only of using `cflush' to get things in memory in
	   preparation for power failure.

	   If we do need to call `cflush', we'll need a target page,
	   as we can only flush one page at a time.

	   Ditto for IA-64. --davidm 00/08/07 */
	mb();
#else
#error "Please define flush_cache."
#endif
}

static __inline__ void my_flush_tlb(void)
{
	__flush_tlb();
}

#ifdef CONFIG_SMP
static void ipi_cache_handler(void *null)
{
	flush_cache();
}

static void ipi_tlb_handler(void *null)
{
	my_flush_tlb();
}

void global_tlb_flush(void)
{
	if (smp_call_function(ipi_tlb_handler, NULL, 1, 1) != 0)
		panic(PFX "timed out waiting for the other CPUs!\n");
	my_flush_tlb();
}

void global_cache_flush(void)
{
	if (smp_call_function(ipi_cache_handler, NULL, 1, 1) != 0)
		panic(PFX "timed out waiting for the other CPUs!\n");
	flush_cache();
}

#else				/* CONFIG_SMP */
void global_tlb_flush(void)
{
	flush_tlb();
}

void global_cache_flush(void)
{
	flush_cache();
}
#endif				/* CONFIG_SMP */

int agp_try_unsupported __initdata = 0;
int agp_memory_reserved;
__u32 *agp_gatt_table;

/* Will be removed in the future: full multiple agp isn't properly
 * cooked just yet.
 */
agp_context agp_bridge_dummy;
agp_context *agp_bridge;

int agp_backend_acquire(void)
{
	if (agp_bridge->type == NOT_SUPPORTED) {
		return -EINVAL;
	}
	atomic_inc(&agp_bridge->agp_in_use);

	if (atomic_read(&agp_bridge->agp_in_use) != 1) {
		atomic_dec(&agp_bridge->agp_in_use);
		return -EBUSY;
	}
	MOD_INC_USE_COUNT;
	return 0;
}

void agp_backend_release(void)
{
	if (agp_bridge->type == NOT_SUPPORTED) {
		return;
	}
	atomic_dec(&agp_bridge->agp_in_use);
	MOD_DEC_USE_COUNT;
}

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 = (num_physpages << PAGE_SHIFT) >> 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;
}

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;
	agp_memory *resvd;

	agp_bridge->type = NOT_SUPPORTED;
	agp_bridge->max_memory_agp = agp_find_max();
	agp_bridge->version = &agp_current_version;

	/* Initialize the lists */
	INIT_LIST_HEAD(&agp_bridge->memory_list);
	INIT_LIST_HEAD(&agp_bridge->bound_list);

	/* Initialize the list spinlock */
	spin_lock_init(&agp_bridge->list_lock);

	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;
	}

	/* Initialize the agp vm here */
	rc = agp_initialize_vm(agp_bridge->dev);
	if (rc) {
		printk(KERN_ERR PFX "Error initializing agp vm subsystem.\n");
		return rc;
	}
	/* TODO make this prettier or make it mostly go away */
	if (agp_bridge->needs_scratch_page == TRUE) {
		u8 type_bits = 
			(u8)agp_bridge->mask_memory(0, AGP_NORMAL_MEMORY);

		agp_bridge->scratch_page = 
	     		agp_bridge->agp_alloc_page(PAGE_KERNEL_NOCACHE);

		if (agp_bridge->scratch_page == NULL) {
			printk(KERN_ERR PFX "unable to get memory for "
			       "scratch page.\n");
			return -ENOMEM;
		}
		agp_bridge->scratch_page_addr = (unsigned long)
					page_address(agp_bridge->scratch_page);
		if(agp_bridge->using_64b_gatt == TRUE) {
			agp_bridge->scratch_page_entry = (unsigned long)
				pack_gatt_u64(agp_bridge->scratch_page_addr, 
					      type_bits);
		} else {
			agp_bridge->scratch_page_entry = (unsigned long)
				pack_gatt_u32(agp_bridge->scratch_page_addr, 
					      type_bits);
		}
	}

	size_value = agp_bridge->fetch_size();

	if (size_value == 0) {
		printk(KERN_ERR PFX "unable to determine 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);

	/* Add reserved memory to the global memory list */
	resvd  = kmalloc(sizeof(agp_memory), GFP_KERNEL);
	if(!resvd) {
		printk(KERN_ERR PFX "couldn't allocate memory for reserved "
		       "memory block.");
		rc = -ENOMEM;
		goto err_out;
	}

	agp_bridge->get_reserved_map(resvd);
	INIT_LIST_HEAD(&resvd->memory_list);
	INIT_LIST_HEAD(&resvd->bound_list);
	INIT_LIST_HEAD(&resvd->my_mappings);
	agp_insert_memory_to_full_list(resvd);
	if(resvd->is_bound) agp_insert_memory_to_bound_list(resvd);

	return 0;

err_out:
	if (agp_bridge->needs_scratch_page == TRUE) {
		agp_bridge->agp_free_page(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_clean_up_all_memory();
	agp_bridge->cleanup();
	agp_bridge->free_gatt_table();
	vfree(agp_bridge->key_list);

	if (agp_bridge->needs_scratch_page == TRUE) {
		agp_bridge->agp_free_page(agp_bridge->scratch_page);
	}
}

static int agp_power(struct pm_dev *dev, pm_request_t rq, void *data)
{
	switch(rq) {
	case PM_SUSPEND:
		return agp_bridge->suspend();
	case PM_RESUME:
		agp_bridge->resume();
		return 0;
	}		
	return 0;
}

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 const drm_agp_3_0_t drm_agp_3_0 = {
	get_num_contexts: agp_get_num_contexts,
	get_info_list: agp_get_extended_info,
	free_memory: agp_ctx_free_memory,
	allocate_memory: agp_ctx_allocate_memory,
	bind_memory: agp_ctx_bind_memory,
	unbind_memory: agp_ctx_unbind_memory,
	enable: agp_ctx_enable,
	acquire: agp_ctx_backend_acquire,
	release: agp_ctx_backend_release,
	copy_info: agp_ctx_copy_info,
	get_map: agp_ctx_get_map,
	kmap: agp_ctx_kmap,
	vma_map_memory: agp_ctx_vma_map_memory,
	usermap: agp_ctx_usermap,
	userunmap: agp_ctx_userunmap,
	kunmap: agp_ctx_kunmap,
};

int __init agp_init(void)
{
	int ret_val;

	printk(KERN_INFO "Linux agpgart interface v%d.%d (c) Jeff Hartmann\n",
	       2, 0);
	printk(KERN_INFO "AGP 3.0 Infrastructure (c) Tungsten Graphics\n");
	ret_val = agp_scan_bus();
	if (ret_val) {
		agp_bridge = &agp_bridge_dummy;
		memset(agp_bridge, 0, sizeof(*agp_bridge));
		agp_bridge->type = NOT_SUPPORTED;
		return ret_val;
	}
	ret_val = agp_allocate_contexts();
	if (ret_val) {
		agp_bridge = &agp_bridge_dummy;
		memset(agp_bridge, 0, sizeof(*agp_bridge));
		agp_bridge->type = NOT_SUPPORTED;
		return ret_val;		
	}
	/* The first context is agp_bridge for now */
	agp_bridge = AGP_GET_CONTEXT(0);

	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);
	inter_module_register("drm_agp_3_0", THIS_MODULE, &drm_agp_3_0);
	pm_register(PM_PCI_DEV, PM_PCI_ID(agp_bridge->dev), agp_power);
	agp_debug_print_lists();
	return 0;
}

static void __exit agp_cleanup(void)
{
	agp_vm_print_debug_list();
	agp_debug_print_lists();
	pm_unregister_all(agp_power);
	agp_frontend_cleanup();
	agp_backend_cleanup();
	agp_debug_print_lists();

	inter_module_unregister("drm_agp");
	inter_module_unregister("drm_agp_3_0");
	if(agp_bridge->driver_name) {
		kfree((void *)agp_bridge->driver_name);
		agp_bridge->driver_name = NULL;
	}
	if(agp_bridge == &agp_bridge_dummy) {
		agp_free_info();
	} else {
		agp_free_contexts_and_info();
	}
}

#ifndef CONFIG_GART_IOMMU
module_init(agp_init);
module_exit(agp_cleanup);
#endif