/*      $OpenBSD: pci_map.c,v 1.33 2023/04/13 15:07:43 miod Exp $     */
/*      $NetBSD: pci_map.c,v 1.7 2000/05/10 16:58:42 thorpej Exp $      */

/*-
 * Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum; by William R. Studenmund; by Jason R. Thorpe.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * PCI device mapping.
 */

#include <sys/param.h>
#include <sys/systm.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>

#ifndef PCI_IO_START
#define PCI_IO_START    0
#endif

#ifndef PCI_IO_END
#define PCI_IO_END      0xffffffff
#endif

#ifndef PCI_MEM_START
#define PCI_MEM_START   0
#endif

#ifndef PCI_MEM_END
#define PCI_MEM_END     0xffffffff
#endif


int obsd_pci_io_find(pci_chipset_tag_t, pcitag_t, int, pcireg_t,
    bus_addr_t *, bus_size_t *, int *);
int obsd_pci_mem_find(pci_chipset_tag_t, pcitag_t, int, pcireg_t,
    bus_addr_t *, bus_size_t *, int *);

int
obsd_pci_io_find(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
    bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
{
        pcireg_t address, mask, csr;
        int s;

        if (reg < PCI_MAPREG_START ||
#if 0
            /*
             * Can't do this check; some devices have mapping registers
             * way out in left field.
             */
            reg >= PCI_MAPREG_END ||
#endif
            (reg & 3))
                panic("pci_io_find: bad request");

        /*
         * Section 6.2.5.1, `Address Maps', tells us that:
         *
         * 1) The builtin software should have already mapped the device in a
         * reasonable way.
         *
         * 2) A device which wants 2^n bytes of memory will hardwire the bottom
         * n bits of the address to 0.  As recommended, we write all 1s while
         * the device is disabled and see what we get back.
         */
        s = splhigh();
        csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
        if (csr & PCI_COMMAND_IO_ENABLE)
                pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
                    csr & ~PCI_COMMAND_IO_ENABLE);
        address = pci_conf_read(pc, tag, reg);
        pci_conf_write(pc, tag, reg, 0xffffffff);
        mask = pci_conf_read(pc, tag, reg);
        pci_conf_write(pc, tag, reg, address);
        if (csr & PCI_COMMAND_IO_ENABLE)
                pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
        splx(s);

        if (PCI_MAPREG_TYPE(address) != PCI_MAPREG_TYPE_IO) {
#ifdef DEBUG
                printf("pci_io_find: expected type i/o, found mem\n");
#endif
                return (EINVAL);
        }

        if (PCI_MAPREG_IO_SIZE(mask) == 0) {
#ifdef DEBUG
                printf("pci_io_find: void region\n");
#endif
                return (ENOENT);
        }

        if (basep != 0)
                *basep = PCI_MAPREG_IO_ADDR(address);
        if (sizep != 0)
                *sizep = PCI_MAPREG_IO_SIZE(mask);
        if (flagsp != 0)
                *flagsp = 0;

        return (0);
}

int
obsd_pci_mem_find(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
    bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
{
        pcireg_t address, mask, address1 = 0, mask1 = 0xffffffff, csr;
        u_int64_t waddress, wmask;
        int s, is64bit;

        is64bit = (PCI_MAPREG_MEM_TYPE(type) == PCI_MAPREG_MEM_TYPE_64BIT);

        if (reg < PCI_MAPREG_START ||
#if 0
            /*
             * Can't do this check; some devices have mapping registers
             * way out in left field.
             */
            reg >= PCI_MAPREG_END ||
#endif
            (reg & 3))
                panic("pci_mem_find: bad request");

        if (is64bit && (reg + 4) >= PCI_MAPREG_END)
                panic("pci_mem_find: bad 64-bit request");

        /*
         * Section 6.2.5.1, `Address Maps', tells us that:
         *
         * 1) The builtin software should have already mapped the device in a
         * reasonable way.
         *
         * 2) A device which wants 2^n bytes of memory will hardwire the bottom
         * n bits of the address to 0.  As recommended, we write all 1s while
         * the device is disabled and see what we get back.
         */
        s = splhigh();
        csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
        if (csr & PCI_COMMAND_MEM_ENABLE)
                pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG,
                    csr & ~PCI_COMMAND_MEM_ENABLE);
        address = pci_conf_read(pc, tag, reg);
        pci_conf_write(pc, tag, reg, PCI_MAPREG_MEM_ADDR_MASK);
        mask = pci_conf_read(pc, tag, reg);
        pci_conf_write(pc, tag, reg, address);
        if (is64bit) {
                address1 = pci_conf_read(pc, tag, reg + 4);
                pci_conf_write(pc, tag, reg + 4, 0xffffffff);
                mask1 = pci_conf_read(pc, tag, reg + 4);
                pci_conf_write(pc, tag, reg + 4, address1);
        }
        if (csr & PCI_COMMAND_MEM_ENABLE)
                pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
        splx(s);

        if (PCI_MAPREG_TYPE(address) != PCI_MAPREG_TYPE_MEM) {
#ifdef DEBUG
                printf("pci_mem_find: expected type mem, found i/o\n");
#endif
                return (EINVAL);
        }
        if (type != -1 && 
            PCI_MAPREG_MEM_TYPE(address) != PCI_MAPREG_MEM_TYPE(type)) {
#ifdef DEBUG
                printf("pci_mem_find: expected mem type %08x, found %08x\n",
                    PCI_MAPREG_MEM_TYPE(type),
                    PCI_MAPREG_MEM_TYPE(address));
#endif
                return (EINVAL);
        }

        waddress = (u_int64_t)address1 << 32UL | address;
        wmask = (u_int64_t)mask1 << 32UL | mask;

        if ((is64bit && PCI_MAPREG_MEM64_SIZE(wmask) == 0) ||
            (!is64bit && PCI_MAPREG_MEM_SIZE(mask) == 0)) {
#ifdef DEBUG
                printf("pci_mem_find: void region\n");
#endif
                return (ENOENT);
        }

        switch (PCI_MAPREG_MEM_TYPE(address)) {
        case PCI_MAPREG_MEM_TYPE_32BIT:
        case PCI_MAPREG_MEM_TYPE_32BIT_1M:
                break;
        case PCI_MAPREG_MEM_TYPE_64BIT:
                /*
                 * Handle the case of a 64-bit memory register on a
                 * platform with 32-bit addressing.  Make sure that
                 * the address assigned and the device's memory size
                 * fit in 32 bits.  We implicitly assume that if
                 * bus_addr_t is 64-bit, then so is bus_size_t.
                 */
                if (sizeof(u_int64_t) > sizeof(bus_addr_t) &&
                    (address1 != 0 || mask1 != 0xffffffff)) {
#ifdef DEBUG
                        printf("pci_mem_find: 64-bit memory map which is "
                            "inaccessible on a 32-bit platform\n");
#endif
                        return (EINVAL);
                }
                break;
        default:
#ifdef DEBUG
                printf("pci_mem_find: reserved mapping register type\n");
#endif
                return (EINVAL);
        }

        if (sizeof(u_int64_t) > sizeof(bus_addr_t)) {
                if (basep != 0)
                        *basep = PCI_MAPREG_MEM_ADDR(address);
                if (sizep != 0)
                        *sizep = PCI_MAPREG_MEM_SIZE(mask);
        } else {
                if (basep != 0)
                        *basep = PCI_MAPREG_MEM64_ADDR(waddress);
                if (sizep != 0)
                        *sizep = PCI_MAPREG_MEM64_SIZE(wmask);
        }
        if (flagsp != 0)
                *flagsp =
                    PCI_MAPREG_MEM_PREFETCHABLE(address) ?
                      BUS_SPACE_MAP_PREFETCHABLE : 0;

        return (0);
}

pcireg_t
pci_mapreg_type(pci_chipset_tag_t pc, pcitag_t tag, int reg)
{
        return (_PCI_MAPREG_TYPEBITS(pci_conf_read(pc, tag, reg)));
}

int
pci_mapreg_probe(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t *typep)
{
        pcireg_t address, mask, csr;
        int s;
        
        s = splhigh();
        csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
        if (csr & (PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE))
                pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr &
                    ~(PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE));
        address = pci_conf_read(pc, tag, reg);
        pci_conf_write(pc, tag, reg, 0xffffffff);
        mask = pci_conf_read(pc, tag, reg);
        pci_conf_write(pc, tag, reg, address);
        if (csr & (PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE))
                pci_conf_write(pc, tag, PCI_COMMAND_STATUS_REG, csr);
        splx(s);

        if (mask == 0) /* unimplemented mapping register */
                return (0);

        if (typep)
                *typep = _PCI_MAPREG_TYPEBITS(address);
        return (1);
}

int
pci_mapreg_info(pci_chipset_tag_t pc, pcitag_t tag, int reg, pcireg_t type,
    bus_addr_t *basep, bus_size_t *sizep, int *flagsp)
{

        if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO)
                return (obsd_pci_io_find(pc, tag, reg, type, basep, sizep,
                    flagsp));
        else
                return (obsd_pci_mem_find(pc, tag, reg, type, basep, sizep,
                    flagsp));
}

int
pci_mapreg_assign(struct pci_attach_args *pa, int reg, pcireg_t type,
    bus_addr_t *basep, bus_size_t *sizep)
{
        bus_addr_t base;
        bus_size_t size;
        pcireg_t csr;
        int rv;

        if ((rv = pci_mapreg_info(pa->pa_pc, pa->pa_tag, reg, type,
            &base, &size, NULL)) != 0)
                return (rv);
#if !defined(__sparc64__)
        if (base == 0) {
                struct extent *ex;
                bus_addr_t start, end;

                if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
                        ex = pa->pa_ioex;
                        if (ex != NULL) {
                                start = max(PCI_IO_START, ex->ex_start);
                                end = min(PCI_IO_END, ex->ex_end);
                        }
                } else {
                        ex = pa->pa_memex;
                        if (ex != NULL) {
                                start = max(PCI_MEM_START, ex->ex_start);
                                end = min(PCI_MEM_END, ex->ex_end);
                        }
                }

                if (ex == NULL || extent_alloc_subregion(ex, start, end,
                    size, size, 0, 0, 0, &base))
                        return (EINVAL); /* disabled because of invalid BAR */

                pci_conf_write(pa->pa_pc, pa->pa_tag, reg, base);
                if (PCI_MAPREG_MEM_TYPE(type) == PCI_MAPREG_MEM_TYPE_64BIT)
                        pci_conf_write(pa->pa_pc, pa->pa_tag, reg + 4,
                            (u_int64_t)base >> 32);
        }
#endif

        csr = pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
        if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO)
                csr |= PCI_COMMAND_IO_ENABLE;
        else
                csr |= PCI_COMMAND_MEM_ENABLE;
        /* XXX Should this only be done for devices that do DMA?  */
        csr |= PCI_COMMAND_MASTER_ENABLE;
        pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, csr);

        if (basep != NULL)
                *basep = base;
        if (sizep != NULL)
                *sizep = size;

        return (0);
}

int
pci_mapreg_map(struct pci_attach_args *pa, int reg, pcireg_t type, int flags,
    bus_space_tag_t *tagp, bus_space_handle_t *handlep, bus_addr_t *basep,
    bus_size_t *sizep, bus_size_t maxsize)
{
        bus_space_tag_t tag;
        bus_space_handle_t handle;
        bus_addr_t base;
        bus_size_t size;
        int rv;

        if ((rv = pci_mapreg_assign(pa, reg, type, &base, &size)) != 0)
                return (rv);

        if (PCI_MAPREG_TYPE(type) == PCI_MAPREG_TYPE_IO) {
                if ((pa->pa_flags & PCI_FLAGS_IO_ENABLED) == 0)
                        return (EINVAL);
                tag = pa->pa_iot;
        } else {
                if ((pa->pa_flags & PCI_FLAGS_MEM_ENABLED) == 0)
                        return (EINVAL);
                tag = pa->pa_memt;
        }

        /* The caller can request limitation of the mapping's size. */
        if (maxsize != 0 && size > maxsize) {
#ifdef DEBUG
                printf("pci_mapreg_map: limited PCI mapping from %lx to %lx\n",
                    (u_long)size, (u_long)maxsize);
#endif
                size = maxsize;
        }

        if (bus_space_map(tag, base, size, flags, &handle))
                return (1);

        if (tagp != NULL)
                *tagp = tag;
        if (handlep != NULL)
                *handlep = handle;
        if (basep != NULL)
                *basep = base;
        if (sizep != NULL)
                *sizep = size;

        return (0);
}