/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2005 Eric Anholt
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * Based on reading the Linux 2.6.8.1 driver by Dave Jones.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>

#include <dev/agp/agppriv.h>
#include <dev/agp/agpreg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>

#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/vm_kern.h>
#include <vm/vm_object.h>
#include <vm/pmap.h>
#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/rman.h>

MALLOC_DECLARE(M_AGP);

#define READ4(off)      bus_space_read_4(sc->bst, sc->bsh, off)
#define WRITE4(off,v)   bus_space_write_4(sc->bst, sc->bsh, off, v)

struct agp_ati_softc {
        struct agp_softc agp;
        struct resource *regs;  /* memory mapped control registers */
        bus_space_tag_t bst;    /* bus_space tag */
        bus_space_handle_t bsh; /* bus_space handle */
        u_int32_t       initial_aperture; /* aperture size at startup */
        char            is_rs300;

        /* The GATT */
        u_int32_t       ag_entries;
        u_int32_t      *ag_virtual;     /* virtual address of gatt */
        u_int32_t      *ag_vdir;        /* virtual address of page dir */
        vm_offset_t     ag_pdir;        /* physical address of page dir */
};

static const char*
agp_ati_match(device_t dev)
{
        if (pci_get_class(dev) != PCIC_BRIDGE ||
            pci_get_subclass(dev) != PCIS_BRIDGE_HOST)
                return NULL;

        if (agp_find_caps(dev) == 0)
                return NULL;

        switch (pci_get_devid(dev)) {
        case 0xcab01002:
                return ("ATI RS100 AGP bridge");
        case 0xcab21002:
                return ("ATI RS200 AGP bridge");
        case 0xcbb21002:
                return ("ATI RS200M AGP bridge");
        case 0xcab31002:
                return ("ATI RS250 AGP bridge");
        case 0x58301002:
                return ("ATI RS300_100 AGP bridge");
        case 0x58311002:
                return ("ATI RS300_133 AGP bridge");
        case 0x58321002:
                return ("ATI RS300_166 AGP bridge");
        case 0x58331002:
                return ("ATI RS300_200 AGP bridge");
        }

        return NULL;
}

static int
agp_ati_probe(device_t dev)
{
        const char *desc;

        desc = agp_ati_match(dev);
        if (desc) {
                device_set_desc(dev, desc);
                return 0;
        }

        return ENXIO;
}

static int
agp_ati_alloc_gatt(device_t dev)
{
        struct agp_ati_softc *sc = device_get_softc(dev);
        u_int32_t apsize = AGP_GET_APERTURE(dev);
        u_int32_t entries = apsize >> AGP_PAGE_SHIFT;
        u_int32_t apbase_offset;
        int i;

        /* Alloc the GATT -- pointers to pages of AGP memory */
        sc->ag_entries = entries;
        sc->ag_virtual = kmem_alloc_attr(entries * sizeof(uint32_t),
            M_NOWAIT | M_ZERO, 0, ~0, VM_MEMATTR_WRITE_COMBINING);
        if (sc->ag_virtual == NULL) {
                if (bootverbose)
                        device_printf(dev, "GATT allocation failed\n");
                return ENOMEM;
        }

        /* Alloc the page directory -- pointers to each page of the GATT */
        sc->ag_vdir = kmem_alloc_attr(AGP_PAGE_SIZE, M_NOWAIT | M_ZERO,
            0, ~0, VM_MEMATTR_WRITE_COMBINING);
        if (sc->ag_vdir == NULL) {
                if (bootverbose)
                        device_printf(dev, "pagedir allocation failed\n");
                kmem_free(sc->ag_virtual, entries * sizeof(uint32_t));
                return ENOMEM;
        }
        sc->ag_pdir = vtophys((vm_offset_t)sc->ag_vdir);

        apbase_offset = pci_read_config(dev, AGP_APBASE, 4) >> 22;
        /* Fill in the pagedir's pointers to GATT pages */
        for (i = 0; i < sc->ag_entries / 1024; i++) {
                vm_offset_t va;
                vm_offset_t pa;

                va = ((vm_offset_t)sc->ag_virtual) + i * AGP_PAGE_SIZE;
                pa = vtophys(va);
                sc->ag_vdir[apbase_offset + i] = pa | 1;
        }

        return 0;
}

static int
agp_ati_attach(device_t dev)
{
        struct agp_ati_softc *sc = device_get_softc(dev);
        int error, rid;
        u_int32_t temp;
        u_int32_t apsize_reg, agpmode_reg;

        error = agp_generic_attach(dev);
        if (error)
                return error;

        switch (pci_get_devid(dev)) {
        case 0xcab01002: /* ATI RS100 AGP bridge */
        case 0xcab21002: /* ATI RS200 AGP bridge */
        case 0xcbb21002: /* ATI RS200M AGP bridge */
        case 0xcab31002: /* ATI RS250 AGP bridge */
                sc->is_rs300 = 0;
                apsize_reg = ATI_RS100_APSIZE;
                agpmode_reg = ATI_RS100_IG_AGPMODE;
                break;
        case 0x58301002: /* ATI RS300_100 AGP bridge */
        case 0x58311002: /* ATI RS300_133 AGP bridge */
        case 0x58321002: /* ATI RS300_166 AGP bridge */
        case 0x58331002: /* ATI RS300_200 AGP bridge */
                sc->is_rs300 = 1;
                apsize_reg = ATI_RS300_APSIZE;
                agpmode_reg = ATI_RS300_IG_AGPMODE;
                break;
        default:
                /* Unknown chipset */
                return EINVAL;
        }

        rid = ATI_GART_MMADDR;
        sc->regs = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
        if (!sc->regs) {
                agp_generic_detach(dev);
                return ENOMEM;
        }

        sc->bst = rman_get_bustag(sc->regs);
        sc->bsh = rman_get_bushandle(sc->regs);

        sc->initial_aperture = AGP_GET_APERTURE(dev);

        for (;;) {
                if (agp_ati_alloc_gatt(dev) == 0)
                        break;

                /*
                 * Probably contigmalloc failure. Try reducing the
                 * aperture so that the gatt size reduces.
                 */
                if (AGP_SET_APERTURE(dev, AGP_GET_APERTURE(dev) / 2))
                        return ENOMEM;
        }

        temp = pci_read_config(dev, apsize_reg, 4);
        pci_write_config(dev, apsize_reg, temp | 1, 4);

        pci_write_config(dev, agpmode_reg, 0x20000, 4);

        WRITE4(ATI_GART_FEATURE_ID, 0x00060000);

        temp = pci_read_config(dev, 4, 4);      /* XXX: Magic reg# */
        pci_write_config(dev, 4, temp | (1 << 14), 4);

        WRITE4(ATI_GART_BASE, sc->ag_pdir);

        AGP_FLUSH_TLB(dev);

        return 0;
}

static int
agp_ati_detach(device_t dev)
{
        struct agp_ati_softc *sc = device_get_softc(dev);
        u_int32_t apsize_reg, temp;

        agp_free_cdev(dev);

        if (sc->is_rs300)
                apsize_reg = ATI_RS300_APSIZE;
        else
                apsize_reg = ATI_RS100_APSIZE;

        /* Clear the GATT base */
        WRITE4(ATI_GART_BASE, 0);

        /* Put the aperture back the way it started. */
        AGP_SET_APERTURE(dev, sc->initial_aperture);

        temp = pci_read_config(dev, apsize_reg, 4);
        pci_write_config(dev, apsize_reg, temp & ~1, 4);

        kmem_free(sc->ag_vdir, AGP_PAGE_SIZE);
        kmem_free(sc->ag_virtual, sc->ag_entries * sizeof(uint32_t));

        bus_release_resource(dev, SYS_RES_MEMORY, ATI_GART_MMADDR, sc->regs);
        agp_free_res(dev);

        return 0;
}

static u_int32_t
agp_ati_get_aperture(device_t dev)
{
        struct agp_ati_softc *sc = device_get_softc(dev);
        int size_value;

        if (sc->is_rs300)
                size_value = pci_read_config(dev, ATI_RS300_APSIZE, 4);
        else
                size_value = pci_read_config(dev, ATI_RS100_APSIZE, 4);

        size_value = (size_value & 0x0000000e) >> 1;
        size_value = (32 * 1024 * 1024) << size_value;

        return size_value;
}

static int
agp_ati_set_aperture(device_t dev, u_int32_t aperture)
{
        struct agp_ati_softc *sc = device_get_softc(dev);
        int size_value;
        u_int32_t apsize_reg;

        if (sc->is_rs300)
                apsize_reg = ATI_RS300_APSIZE;
        else
                apsize_reg = ATI_RS100_APSIZE;

        size_value = pci_read_config(dev, apsize_reg, 4);

        size_value &= ~0x0000000e;
        size_value |= (ffs(aperture / (32 * 1024 * 1024)) - 1) << 1;

        pci_write_config(dev, apsize_reg, size_value, 4);

        return 0;
}

static int
agp_ati_bind_page(device_t dev, vm_offset_t offset, vm_offset_t physical)
{
        struct agp_ati_softc *sc = device_get_softc(dev);

        if (offset >= (sc->ag_entries << AGP_PAGE_SHIFT))
                return EINVAL;

        sc->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical | 1;

        return 0;
}

static int
agp_ati_unbind_page(device_t dev, vm_offset_t offset)
{
        struct agp_ati_softc *sc = device_get_softc(dev);

        if (offset >= (sc->ag_entries << AGP_PAGE_SHIFT))
                return EINVAL;

        sc->ag_virtual[offset >> AGP_PAGE_SHIFT] = 0;
        return 0;
}

static void
agp_ati_flush_tlb(device_t dev)
{
        struct agp_ati_softc *sc = device_get_softc(dev);

        /* Set the cache invalidate bit and wait for the chipset to clear */
        WRITE4(ATI_GART_CACHE_CNTRL, 1);
        (void)READ4(ATI_GART_CACHE_CNTRL);
}

static device_method_t agp_ati_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         agp_ati_probe),
        DEVMETHOD(device_attach,        agp_ati_attach),
        DEVMETHOD(device_detach,        agp_ati_detach),
        DEVMETHOD(device_shutdown,      bus_generic_shutdown),
        DEVMETHOD(device_suspend,       bus_generic_suspend),
        DEVMETHOD(device_resume,        bus_generic_resume),

        /* AGP interface */
        DEVMETHOD(agp_get_aperture,     agp_ati_get_aperture),
        DEVMETHOD(agp_set_aperture,     agp_ati_set_aperture),
        DEVMETHOD(agp_bind_page,        agp_ati_bind_page),
        DEVMETHOD(agp_unbind_page,      agp_ati_unbind_page),
        DEVMETHOD(agp_flush_tlb,        agp_ati_flush_tlb),
        DEVMETHOD(agp_enable,           agp_generic_enable),
        DEVMETHOD(agp_alloc_memory,     agp_generic_alloc_memory),
        DEVMETHOD(agp_free_memory,      agp_generic_free_memory),
        DEVMETHOD(agp_bind_memory,      agp_generic_bind_memory),
        DEVMETHOD(agp_unbind_memory,    agp_generic_unbind_memory),
        DEVMETHOD_END
};

static driver_t agp_ati_driver = {
        "agp",
        agp_ati_methods,
        sizeof(struct agp_ati_softc),
};

DRIVER_MODULE(agp_ati, hostb, agp_ati_driver, 0, 0);
MODULE_DEPEND(agp_ati, agp, 1, 1, 1);
MODULE_DEPEND(agp_ati, pci, 1, 1, 1);