#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/agp_backend.h>
#include <linux/mm.h>
#include <linux/slab.h>

#include <asm/machvec.h>
#include <asm/agp_backend.h>
#include "../../../arch/alpha/kernel/pci_impl.h"

#include "agp.h"

static vm_fault_t alpha_core_agp_vm_fault(struct vm_fault *vmf)
{
        alpha_agp_info *agp = agp_bridge->dev_private_data;
        dma_addr_t dma_addr;
        unsigned long pa;
        struct page *page;

        dma_addr = vmf->address - vmf->vma->vm_start + agp->aperture.bus_base;
        pa = agp->ops->translate(agp, dma_addr);

        if (pa == (unsigned long)-EINVAL)
                return VM_FAULT_SIGBUS; /* no translation */

        /*
         * Get the page, inc the use count, and return it
         */
        page = virt_to_page(__va(pa));
        get_page(page);
        vmf->page = page;
        return 0;
}

static struct aper_size_info_fixed alpha_core_agp_sizes[] =
{
        { 0, 0, 0 }, /* filled in by alpha_core_agp_setup */
};

static const struct vm_operations_struct alpha_core_agp_vm_ops = {
        .fault = alpha_core_agp_vm_fault,
};


static int alpha_core_agp_fetch_size(void)
{
        return alpha_core_agp_sizes[0].size;
}

static int alpha_core_agp_configure(void)
{
        alpha_agp_info *agp = agp_bridge->dev_private_data;
        agp_bridge->gart_bus_addr = agp->aperture.bus_base;
        return 0;
}

static void alpha_core_agp_cleanup(void)
{
        alpha_agp_info *agp = agp_bridge->dev_private_data;

        agp->ops->cleanup(agp);
}

static void alpha_core_agp_tlbflush(struct agp_memory *mem)
{
        alpha_agp_info *agp = agp_bridge->dev_private_data;
        alpha_mv.mv_pci_tbi(agp->hose, 0, -1);
}

static void alpha_core_agp_enable(struct agp_bridge_data *bridge, u32 mode)
{
        alpha_agp_info *agp = bridge->dev_private_data;

        agp->mode.lw = agp_collect_device_status(bridge, mode,
                                        agp->capability.lw);

        agp->mode.bits.enable = 1;
        agp->ops->configure(agp);

        agp_device_command(agp->mode.lw, false);
}

static int alpha_core_agp_insert_memory(struct agp_memory *mem, off_t pg_start,
                                        int type)
{
        alpha_agp_info *agp = agp_bridge->dev_private_data;
        int num_entries, status;
        void *temp;

        if (type >= AGP_USER_TYPES || mem->type >= AGP_USER_TYPES)
                return -EINVAL;

        temp = agp_bridge->current_size;
        num_entries = A_SIZE_FIX(temp)->num_entries;
        if ((pg_start + mem->page_count) > num_entries)
                return -EINVAL;

        status = agp->ops->bind(agp, pg_start, mem);
        mb();
        alpha_core_agp_tlbflush(mem);

        return status;
}

static int alpha_core_agp_remove_memory(struct agp_memory *mem, off_t pg_start,
                                        int type)
{
        alpha_agp_info *agp = agp_bridge->dev_private_data;
        int status;

        status = agp->ops->unbind(agp, pg_start, mem);
        alpha_core_agp_tlbflush(mem);
        return status;
}

static int alpha_core_agp_create_free_gatt_table(struct agp_bridge_data *a)
{
        return 0;
}

struct agp_bridge_driver alpha_core_agp_driver = {
        .owner                  = THIS_MODULE,
        .aperture_sizes         = alpha_core_agp_sizes,
        .num_aperture_sizes     = 1,
        .size_type              = FIXED_APER_SIZE,
        .cant_use_aperture      = true,
        .masks                  = NULL,

        .fetch_size             = alpha_core_agp_fetch_size,
        .configure              = alpha_core_agp_configure,
        .agp_enable             = alpha_core_agp_enable,
        .cleanup                = alpha_core_agp_cleanup,
        .tlb_flush              = alpha_core_agp_tlbflush,
        .mask_memory            = agp_generic_mask_memory,
        .cache_flush            = global_cache_flush,
        .create_gatt_table      = alpha_core_agp_create_free_gatt_table,
        .free_gatt_table        = alpha_core_agp_create_free_gatt_table,
        .insert_memory          = alpha_core_agp_insert_memory,
        .remove_memory          = alpha_core_agp_remove_memory,
        .alloc_by_type          = agp_generic_alloc_by_type,
        .free_by_type           = agp_generic_free_by_type,
        .agp_alloc_page         = agp_generic_alloc_page,
        .agp_alloc_pages        = agp_generic_alloc_pages,
        .agp_destroy_page       = agp_generic_destroy_page,
        .agp_destroy_pages      = agp_generic_destroy_pages,
        .agp_type_to_mask_type  = agp_generic_type_to_mask_type,
};

struct agp_bridge_data *alpha_bridge;

static int __init
alpha_core_agp_setup(void)
{
        alpha_agp_info *agp = alpha_mv.agp_info();
        struct pci_dev *pdev;   /* faked */
        struct aper_size_info_fixed *aper_size;

        if (!agp)
                return -ENODEV;
        if (agp->ops->setup(agp))
                return -ENODEV;

        /*
         * Build the aperture size descriptor
         */
        aper_size = alpha_core_agp_sizes;
        aper_size->size = agp->aperture.size / (1024 * 1024);
        aper_size->num_entries = agp->aperture.size / PAGE_SIZE;
        aper_size->page_order = __ffs(aper_size->num_entries / 1024);

        /*
         * Build a fake pci_dev struct
         */
        pdev = pci_alloc_dev(NULL);
        if (!pdev)
                return -ENOMEM;
        pdev->vendor = 0xffff;
        pdev->device = 0xffff;
        pdev->sysdata = agp->hose;

        alpha_bridge = agp_alloc_bridge();
        if (!alpha_bridge)
                goto fail;

        alpha_bridge->driver = &alpha_core_agp_driver;
        alpha_bridge->vm_ops = &alpha_core_agp_vm_ops;
        alpha_bridge->current_size = aper_size; /* only 1 size */
        alpha_bridge->dev_private_data = agp;
        alpha_bridge->dev = pdev;
        alpha_bridge->mode = agp->capability.lw;

        printk(KERN_INFO PFX "Detected AGP on hose %d\n", agp->hose->index);
        return agp_add_bridge(alpha_bridge);

 fail:
        kfree(pdev);
        return -ENOMEM;
}

static int __init agp_alpha_core_init(void)
{
        if (agp_off)
                return -EINVAL;
        if (alpha_mv.agp_info)
                return alpha_core_agp_setup();
        return -ENODEV;
}

static void __exit agp_alpha_core_cleanup(void)
{
        agp_remove_bridge(alpha_bridge);
        agp_put_bridge(alpha_bridge);
}

module_init(agp_alpha_core_init);
module_exit(agp_alpha_core_cleanup);

MODULE_AUTHOR("Jeff Wiedemeier <Jeff.Wiedemeier@hp.com>");
MODULE_DESCRIPTION("Alpha AGP support");
MODULE_LICENSE("GPL and additional rights");