/*      $OpenBSD: agp_via.c,v 1.23 2024/05/24 06:02:53 jsg Exp $        */
/*      $NetBSD: agp_via.c,v 1.2 2001/09/15 00:25:00 thorpej 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/param.h>
#include <sys/systm.h>
#include <sys/device.h>

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

#include <machine/bus.h>

struct agp_via_softc {
        struct device            dev;
        struct agp_softc        *agpdev;
        struct agp_gatt         *gatt;
        int                     *regs;
        pci_chipset_tag_t        vsc_pc;
        pcitag_t                 vsc_tag;
        bus_addr_t               vsc_apaddr;
        bus_size_t               vsc_apsize;
        pcireg_t                 vsc_regapsize;
        pcireg_t                 vsc_regattbase;
        pcireg_t                 vsc_reggartctl;
};

void    agp_via_attach(struct device *, struct device *, void *);
int     agp_via_activate(struct device *, int);
void    agp_via_save(struct agp_via_softc *);
void    agp_via_restore(struct agp_via_softc *);
int     agp_via_probe(struct device *, void *, void *);
bus_size_t agp_via_get_aperture(void *);
int     agp_via_set_aperture(void *, bus_size_t);
void    agp_via_bind_page(void *, bus_addr_t, paddr_t, int);
void    agp_via_unbind_page(void *, bus_addr_t);
void    agp_via_flush_tlb(void *);

const struct agp_methods agp_via_methods = {
        agp_via_bind_page,
        agp_via_unbind_page,
        agp_via_flush_tlb,
};

const struct cfattach viaagp_ca = {
        sizeof(struct agp_via_softc), agp_via_probe, agp_via_attach,
        NULL, agp_via_activate
};

struct cfdriver viaagp_cd = {
        NULL, "viaagp", DV_DULL
};

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

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

int
agp_via_probe(struct device *parent, void *match, void *aux)
{
        struct agp_attach_args  *aa = aux;
        struct pci_attach_args  *pa = aa->aa_pa;

        /* Must be a pchb don't attach to iommu-style agp devs */
        if (agpbus_probe(aa) == 1 &&
            PCI_VENDOR(pa->pa_id) == PCI_VENDOR_VIATECH &&
            PCI_PRODUCT(pa->pa_id) != PCI_PRODUCT_VIATECH_K8M800_0 &&
            PCI_PRODUCT(pa->pa_id) != PCI_PRODUCT_VIATECH_K8T890_0 &&
            PCI_PRODUCT(pa->pa_id) != PCI_PRODUCT_VIATECH_K8HTB_0 &&
            PCI_PRODUCT(pa->pa_id) != PCI_PRODUCT_VIATECH_K8HTB)
                return (1);
        return (0);
}

void
agp_via_attach(struct device *parent, struct device *self, void *aux)
{
        struct agp_via_softc    *vsc = (struct agp_via_softc *)self;
        struct agp_attach_args  *aa = aux;
        struct pci_attach_args  *pa = aa->aa_pa;
        struct agp_gatt         *gatt;
        pcireg_t                 agpsel, capval;

        vsc->vsc_pc = pa->pa_pc;
        vsc->vsc_tag = pa->pa_tag;
        pci_get_capability(pa->pa_pc, pa->pa_tag, PCI_CAP_AGP, NULL, &capval);

        if (pci_mapreg_info(pa->pa_pc, pa->pa_tag, AGP_APBASE,
            PCI_MAPREG_TYPE_MEM, &vsc->vsc_apaddr, NULL, NULL) != 0) {
                printf(": can't get aperture info\n");
                return;
        }

        if (AGP_CAPID_GET_MAJOR(capval) >= 3) {
                agpsel = pci_conf_read(pa->pa_pc, pa->pa_tag,
                                AGP_VIA_AGPSEL_REG);
                if ((agpsel & (1 << 9)) == 0) {
                        vsc->regs = via_v3_regs;
                        printf(": v3");
                } else {
                        vsc->regs = via_v2_regs;
                        printf(": v2 compat mode");
                }
        } else {
                vsc->regs = via_v2_regs;
                printf(": v2");
        }


        vsc->vsc_apsize = agp_via_get_aperture(vsc);

        for (;;) {
                gatt = agp_alloc_gatt(pa->pa_dmat, vsc->vsc_apsize);
                if (gatt != NULL)
                        break;

                /*
                 * Probably failed to alloc contiguous memory. Try reducing the
                 * aperture so that the gatt size reduces.
                 */
                vsc->vsc_apsize /= 2;
                if (agp_via_set_aperture(vsc, vsc->vsc_apsize)) {
                        printf(", can't set aperture size\n");
                        return;
                }
        }
        vsc->gatt = gatt;

        if (vsc->regs == via_v2_regs) {
                /* Install the gatt. */
                pci_conf_write(pa->pa_pc, pa->pa_tag, vsc->regs[REG_ATTBASE],
                    gatt->ag_physical | 3);
                /* Enable the aperture. */
                pci_conf_write(pa->pa_pc, pa->pa_tag, vsc->regs[REG_GARTCTRL],
                    0x0000000f);
        } else {
                pcireg_t gartctrl;
                /* Install the gatt. */
                pci_conf_write(pa->pa_pc, pa->pa_tag, vsc->regs[REG_ATTBASE],
                    gatt->ag_physical);
                /* Enable the aperture. */
                gartctrl = pci_conf_read(pa->pa_pc, pa->pa_tag,
                    vsc->regs[REG_ATTBASE]);
                pci_conf_write(pa->pa_pc, pa->pa_tag, vsc->regs[REG_GARTCTRL],
                    gartctrl | (3 << 7));
        }
        vsc->agpdev = (struct agp_softc *)agp_attach_bus(pa, &agp_via_methods,
            vsc->vsc_apaddr, vsc->vsc_apsize, &vsc->dev);

        return;
}

int
agp_via_activate(struct device *arg, int act)
{
        struct agp_via_softc *vsc = (struct agp_via_softc *)arg;

        switch (act) {
        case DVACT_SUSPEND:
                agp_via_save(vsc);
                break;
        case DVACT_RESUME:
                agp_via_restore(vsc);
                break;
        }

        return (0);
}

void
agp_via_save(struct agp_via_softc *vsc)
{
        vsc->vsc_regapsize = pci_conf_read(vsc->vsc_pc, vsc->vsc_tag,
            vsc->regs[REG_APSIZE]);
        vsc->vsc_regattbase = pci_conf_read(vsc->vsc_pc, vsc->vsc_tag,
            vsc->regs[REG_ATTBASE]);
        vsc->vsc_reggartctl = pci_conf_read(vsc->vsc_pc, vsc->vsc_tag,
            vsc->regs[REG_GARTCTRL]);
}
void
agp_via_restore(struct agp_via_softc *vsc)
{

        /* aperture size */
        pci_conf_write(vsc->vsc_pc, vsc->vsc_tag, vsc->regs[REG_APSIZE],
            vsc->vsc_regapsize);
        /* GATT address and enable */
        pci_conf_write(vsc->vsc_pc, vsc->vsc_tag, vsc->regs[REG_ATTBASE],
            vsc->vsc_regattbase);
        /* Turn it all back on. */
        pci_conf_write(vsc->vsc_pc, vsc->vsc_tag, vsc->regs[REG_GARTCTRL],
            vsc->vsc_reggartctl);
        /* flush the tlb, just in case */
        agp_via_flush_tlb(vsc);
}

bus_size_t
agp_via_get_aperture(void *sc)
{
        struct agp_via_softc    *vsc = sc;
        bus_size_t               apsize;

        apsize = pci_conf_read(vsc->vsc_pc, vsc->vsc_tag, 
            vsc->regs[REG_APSIZE]) & 0x1f;

        /*
         * 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);
}

int
agp_via_set_aperture(void *sc, bus_size_t aperture)
{
        struct agp_via_softc    *vsc = sc;
        bus_size_t               apsize;
        pcireg_t                 reg;

        /*
         * 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(vsc->vsc_pc, vsc->vsc_tag, vsc->regs[REG_APSIZE]);
        reg &= ~0xff;
        reg |= apsize;
        pci_conf_write(vsc->vsc_pc, vsc->vsc_tag, vsc->regs[REG_APSIZE], reg);

        return (0);
}

void
agp_via_bind_page(void *sc, bus_addr_t offset, paddr_t physical, int flags)
{
        struct agp_via_softc *vsc = sc;

        vsc->gatt->ag_virtual[(offset - vsc->vsc_apaddr) >> AGP_PAGE_SHIFT] =
            physical;
}

void
agp_via_unbind_page(void *sc, bus_addr_t offset)
{
        struct agp_via_softc *vsc = sc;

        vsc->gatt->ag_virtual[(offset - vsc->vsc_apaddr) >> AGP_PAGE_SHIFT] = 0;
}

void
agp_via_flush_tlb(void *sc)
{
        struct agp_via_softc *vsc = sc;
        pcireg_t gartctrl;

        if (vsc->regs == via_v2_regs) {
                pci_conf_write(vsc->vsc_pc, vsc->vsc_tag,
                    vsc->regs[REG_GARTCTRL], 0x8f);
                pci_conf_write(vsc->vsc_pc, vsc->vsc_tag,
                    vsc->regs[REG_GARTCTRL], 0x0f);
        } else {
                gartctrl = pci_conf_read(vsc->vsc_pc, vsc->vsc_tag,
                    vsc->regs[REG_GARTCTRL]);
                pci_conf_write(vsc->vsc_pc, vsc->vsc_tag,
                    vsc->regs[REG_GARTCTRL], gartctrl & ~(1 << 7));
                pci_conf_write(vsc->vsc_pc, vsc->vsc_tag,
                    vsc->regs[REG_GARTCTRL], gartctrl);
        }
}