root/sys/arch/prep/stand/boot/pci.c
/*      $NetBSD: pci.c,v 1.3 2022/02/16 23:49:27 riastradh Exp $        */

/*
 * Copyright (C) 1995-1997 Gary Thomas (gdt@linuxppc.org)
 * All rights reserved.
 *
 * Adapted from a program by:
 *                                      Steve Sellgren
 *                                      San Francisco Indigo Company
 *                                      sfindigo!sellgren@uunet.uu.net
 * Adapted for Moto boxes by:
 *                                      Pat Kane & Mark Scott, 1996
 * Fixed for IBM/PowerStack II          Pat Kane 1997
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Gary Thomas.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */

#include <lib/libsa/stand.h>
#include <sys/bswap.h>
#include <dev/pci/pcireg.h>

#include "boot.h"

#define PCI_NSLOTS      8
#define PCI_NREGS       10

/*
 * should use devfunc number/indirect method to be totally safe on
 * all machines, this works for now on 3 slot Moto boxes
 */

#define PCI_CONFIG_SPACE_BASE   0x80800000
#define PCI_CONFIG_SPACE(d, f)  \
                (u_long *)(PCI_CONFIG_SPACE_BASE | (1 << (d)) | ((f) << 8))

#define DEVID           (PCI_ID_REG >> 2)
#define CMD             (PCI_COMMAND_STATUS_REG >> 2)
#define CLASS           (PCI_CLASS_REG >> 2)
#define BAR_BASE        (PCI_MAPREG_START >> 2)

struct PCI_cinfo {
        u_long *config_addr;
        u_long regs[PCI_NREGS];
} PCI_slots[PCI_NSLOTS] = {
        { (u_long *)0x80808000, {0xDEADBEEF,} },
        { (u_long *)0x80800800, {0xDEADBEEF,} },
        { (u_long *)0x80801000, {0xDEADBEEF,} },
        { (u_long *)0x80802000, {0xDEADBEEF,} },
        { (u_long *)0x80804000, {0xDEADBEEF,} },
        { (u_long *)0x80810000, {0xDEADBEEF,} },
        { (u_long *)0x80820000, {0xDEADBEEF,} },
        { (u_long *)0x80840000, {0xDEADBEEF,} },
};

/*
 * The following code modifies the PCI Command register
 * to enable memory and I/O accesses.
 */
void
enablePCI(int slot, int io, int mem, int master)
{
        volatile u_char *ppci;
        u_char enable = 0;

        if (io)
                enable |= PCI_COMMAND_IO_ENABLE;
        if (mem)
                enable |= PCI_COMMAND_MEM_ENABLE;
        if (master)
                enable |= PCI_COMMAND_MASTER_ENABLE;

        ppci = (u_char *)&PCI_slots[slot].config_addr[CMD];
        *ppci = enable;
        __asm volatile("eieio" ::: "memory");
}

int
PCISlotnum(u_int bus, u_int dev, u_int func)
{
        u_long *tag;
        int i;

        if (bus != 0 ||
            dev < 8 || dev > 18 ||
            func > 7)
                return -1;

        tag = PCI_CONFIG_SPACE(dev, func);
        for (i = 0; i < sizeof(PCI_slots) / sizeof(struct PCI_cinfo); i++)
                if (tag == PCI_slots[i].config_addr)
                        return i;
        return -1;
}

/* return mapped address for I/O or Memory */
u_long
PCIAddress(int slotnum, u_int bar, int type)
{
        struct PCI_cinfo *pslot;

        if (bar >= 6)
                return 0xffffffff;

        pslot = &PCI_slots[slotnum];

        if (pslot->regs[DEVID] == 0xffffffff ||
            PCI_MAPREG_TYPE(pslot->regs[BAR_BASE + bar]) != type)
                return 0xffffffff;

        return PCI_MAPREG_MEM_ADDR(pslot->regs[BAR_BASE + bar]);
}

void
unlockVideo(int slot)
{
        volatile u_int8_t *ppci;

        ppci = (u_int8_t *)PCI_slots[slot].config_addr;
        ppci[4] = 0x0003;       /* enable memory and IO Access */
#if 0
        ppci[0x10] = 0x00000;   /* Turn off memory mapping */
        ppci[0x11] = 0x00000;   /* mem base = 0 */
        ppci[0x12] = 0x00000;
        ppci[0x13] = 0x00000;
#endif
        __asm__ volatile("eieio" ::: "memory");

        outb(0x3d4, 0x11);
        outb(0x3d5, 0x0e);   /* unlock CR0-CR7 */
}

int
scan_PCI(int start)
{
        int slot, r;
        struct PCI_cinfo *pslot;
        int VGAslot = -1;

        for (slot = start + 1; slot < PCI_NSLOTS; slot++) {
                pslot = &PCI_slots[slot];
                for (r = 0; r < PCI_NREGS; r++)
                        pslot->regs[r] = bswap32(pslot->config_addr[r]);
                if (pslot->regs[DEVID] != 0xffffffff) {
                        /* we have a card */
                        if (((pslot->regs[CLASS] & 0xffffff00) == 
                                0x03000000) ||
                            ((pslot->regs[CLASS] & 0xffffff00) ==
                                0x00010000)) {
                                /* it's a VGA card */
                                if ((pslot->regs[CMD] & 0x03)) {
                                        /* fW enabled it */
                                        VGAslot = slot;
                                        break;
                                }
                        }
                }
        }
        return VGAslot;
}

int
PCI_vendor(int slotnum)
{
        struct PCI_cinfo *pslot = &PCI_slots[slotnum];

        return (pslot->regs[DEVID] & 0xffff);
}