/*      $NetBSD: agp_via.c,v 1.23 2026/06/21 17:09:44 andvar Exp $      */

/*-
 * Copyright (c) 2000 Doug Rabson
 * 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.
 *
 *      $FreeBSD: src/sys/pci/agp_via.c,v 1.3 2001/07/05 21:28:47 jhb Exp $
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: agp_via.c,v 1.23 2026/06/21 17:09:44 andvar Exp $");

#include <sys/param.h>
#include <sys/agpio.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/systm.h>

#include <dev/pci/agpreg.h>
#include <dev/pci/agpvar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcidevs.h>

static u_int32_t agp_via_get_aperture(struct agp_softc *);
static int agp_via_set_aperture(struct agp_softc *, u_int32_t);
static int agp_via_bind_page(struct agp_softc *, off_t, bus_addr_t);
static int agp_via_unbind_page(struct agp_softc *, off_t);
static void agp_via_flush_tlb(struct agp_softc *);

static struct agp_methods agp_via_methods = {
        agp_via_get_aperture,
        agp_via_set_aperture,
        agp_via_bind_page,
        agp_via_unbind_page,
        agp_via_flush_tlb,
        agp_generic_enable,
        agp_generic_alloc_memory,
        agp_generic_free_memory,
        agp_generic_bind_memory,
        agp_generic_unbind_memory,
};

struct agp_via_softc {
        u_int32_t       initial_aperture; /* aperture size at startup */
        struct agp_gatt *gatt;
        int             *regs;
};

#define REG_GARTCTRL    0
#define REG_APSIZE      1
#define REG_ATTBASE     2

static int via_v2_regs[] =
        { AGP_VIA_GARTCTRL, AGP_VIA_APSIZE, AGP_VIA_ATTBASE };
static int via_v3_regs[] =
        { AGP3_VIA_GARTCTRL, AGP3_VIA_APSIZE, AGP3_VIA_ATTBASE };

int
agp_via_attach(device_t parent, device_t self, void *aux)
{
        struct pci_attach_args *pa = aux;
        struct agp_softc *sc = device_private(self);
        struct agp_via_softc *asc;
        struct agp_gatt *gatt;
        pcireg_t agpsel, capval;

        asc = malloc(sizeof *asc, M_AGP, M_WAITOK|M_ZERO);
        sc->as_chipc = asc;
        sc->as_methods = &agp_via_methods;
        pci_get_capability(pa->pa_pc, pa->pa_tag, PCI_CAP_AGP, &sc->as_capoff,
            &capval);

        if (PCI_CAP_AGP_MAJOR(capval) >= 3) {
                agpsel = pci_conf_read(pa->pa_pc, pa->pa_tag, AGP_VIA_AGPSEL);
                if ((agpsel & (1 << 9)) == 0) {
                        asc->regs = via_v3_regs;
                        aprint_debug(" (v3)");
                } else {
                        asc->regs = via_v2_regs;
                        aprint_debug(" (v2 compat mode)");
                }
        } else {
                asc->regs = via_v2_regs;
                aprint_debug(" (v2)");
        }

        if (agp_map_aperture(pa, sc, AGP_APBASE) != 0) {
                aprint_error(": can't map aperture\n");
                free(asc, M_AGP);
                return ENXIO;
        }

        asc->initial_aperture = AGP_GET_APERTURE(sc);

        for (;;) {
                gatt = agp_alloc_gatt(sc);
                if (gatt)
                        break;

                /*
                 * Probably contigmalloc failure. Try reducing the
                 * aperture so that the gatt size reduces.
                 */
                if (AGP_SET_APERTURE(sc, AGP_GET_APERTURE(sc) / 2)) {
                        agp_generic_detach(sc);
                        aprint_error(": can't set aperture size\n");
                        return ENOMEM;
                }
        }
        asc->gatt = gatt;

        if (asc->regs == via_v2_regs) {
                /* Install the gatt. */
                pci_conf_write(pa->pa_pc, pa->pa_tag, asc->regs[REG_ATTBASE],
                                 gatt->ag_physical | 3);
                /* Enable the aperture. */
                pci_conf_write(pa->pa_pc, pa->pa_tag, asc->regs[REG_GARTCTRL],
                                 0x0000000f);
        } else {
                pcireg_t gartctrl;
                /* Install the gatt. */
                pci_conf_write(pa->pa_pc, pa->pa_tag, asc->regs[REG_ATTBASE],
                                 gatt->ag_physical);
                /* Enable the aperture. */
                gartctrl = pci_conf_read(pa->pa_pc, pa->pa_tag,
                                 asc->regs[REG_GARTCTRL]);
                pci_conf_write(pa->pa_pc, pa->pa_tag, asc->regs[REG_GARTCTRL],
                                 gartctrl | (3 << 7));
        }

        return 0;
}

#if 0
static int
agp_via_detach(struct agp_softc *sc)
{
        struct agp_via_softc *asc = sc->as_chipc;
        int error;

        error = agp_generic_detach(sc);
        if (error)
                return error;

        pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_GARTCTRL], 0);
        pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_ATTBASE], 0);
        AGP_SET_APERTURE(sc, asc->initial_aperture);
        agp_free_gatt(sc, asc->gatt);

        return 0;
}
#endif

static u_int32_t
agp_via_get_aperture(struct agp_softc *sc)
{
        struct agp_via_softc *asc = sc->as_chipc;
        u_int32_t apsize;

        if (asc->regs == via_v2_regs) {
                apsize = pci_conf_read(sc->as_pc, sc->as_tag,
                                asc->regs[REG_APSIZE]) & 0xff;

                /*
                 * The size is determined by the number of low bits of
                 * register APBASE which are forced to zero. The low 20 bits
                 * are always forced to zero and each zero bit in the apsize
                 * field just read forces the corresponding bit in the 27:20
                 * to be zero. We calculate the aperture size accordingly.
                 */
                return (((apsize ^ 0xff) << 20) | ((1 << 20) - 1)) + 1;
        } else {
                apsize = pci_conf_read(sc->as_pc, sc->as_tag,
                                asc->regs[REG_APSIZE]) & 0xfff;
                switch (apsize) {
                case 0x800:
                        return 0x80000000;
                case 0xc00:
                        return 0x40000000;
                case 0xe00:
                        return 0x20000000;
                case 0xf00:
                        return 0x10000000;
                case 0xf20:
                        return 0x08000000;
                case 0xf30:
                        return 0x04000000;
                case 0xf38:
                        return 0x02000000;
                case 0xf3c:
                        return 0x01000000;
                case 0xf3e:
                        return 0x00800000;
                case 0xf3f:
                        return 0x00400000;
                default:
                        aprint_error_dev(sc->as_dev,
                            "invalid aperture setting 0x%x\n", apsize);
                        return 0;
                }
        }
}

static int
agp_via_set_aperture(struct agp_softc *sc, u_int32_t aperture)
{
        struct agp_via_softc *asc = sc->as_chipc;
        u_int32_t apsize, key;
        pcireg_t reg;

        if (asc->regs == via_v2_regs) {
                /*
                 * Reverse the magic from get_aperture.
                 */
                apsize = ((aperture - 1) >> 20) ^ 0xff;

                /*
                 * Double check for sanity.
                 */
                if ((((apsize ^ 0xff) << 20) | ((1 << 20) - 1)) + 1 != aperture)
                        return EINVAL;

                reg = pci_conf_read(sc->as_pc, sc->as_tag,
                    asc->regs[REG_APSIZE]);
                reg &= ~0xff;
                reg |= apsize;
                pci_conf_write(sc->as_pc, sc->as_tag,
                    asc->regs[REG_APSIZE], reg);
        } else {
                switch (aperture) {
                case 0x80000000:
                        key = 0x800;
                        break;
                case 0x40000000:
                        key = 0xc00;
                        break;
                case 0x20000000:
                        key = 0xe00;
                        break;
                case 0x10000000:
                        key = 0xf00;
                        break;
                case 0x08000000:
                        key = 0xf20;
                        break;
                case 0x04000000:
                        key = 0xf30;
                        break;
                case 0x02000000:
                        key = 0xf38;
                        break;
                case 0x01000000:
                        key = 0xf3c;
                        break;
                case 0x00800000:
                        key = 0xf3e;
                        break;
                case 0x00400000:
                        key = 0xf3f;
                        break;
                default:
                        aprint_error_dev(sc->as_dev,
                            "invalid aperture size (%dMB)\n",
                            aperture / 1024 / 1024);
                        return EINVAL;
                }
                reg = pci_conf_read(sc->as_pc, sc->as_tag, asc->regs[REG_APSIZE]);
                reg &= ~0xfff;
                reg |= key;
                pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_APSIZE], reg);
        }

        return 0;
}

static int
agp_via_bind_page(struct agp_softc *sc, off_t offset, bus_addr_t physical)
{
        struct agp_via_softc *asc = sc->as_chipc;

        if (offset < 0 || offset >= (asc->gatt->ag_entries << AGP_PAGE_SHIFT))
                return EINVAL;

        asc->gatt->ag_virtual[offset >> AGP_PAGE_SHIFT] = physical;
        return 0;
}

static int
agp_via_unbind_page(struct agp_softc *sc, off_t offset)
{
        struct agp_via_softc *asc = sc->as_chipc;

        if (offset < 0 || offset >= (asc->gatt->ag_entries << AGP_PAGE_SHIFT))
                return EINVAL;

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

static void
agp_via_flush_tlb(struct agp_softc *sc)
{
        struct agp_via_softc *asc = sc->as_chipc;
        pcireg_t gartctrl;

        if (asc->regs == via_v2_regs) {
                pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_GARTCTRL],
                                0x8f);
                pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_GARTCTRL],
                                0x0f);
        } else {
                gartctrl = pci_conf_read(sc->as_pc, sc->as_tag,
                                         asc->regs[REG_GARTCTRL]);
                pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_GARTCTRL],
                               gartctrl & ~(1 << 7));
                pci_conf_write(sc->as_pc, sc->as_tag, asc->regs[REG_GARTCTRL],
                               gartctrl);
        }
}