/*      $NetBSD: bootxx.c,v 1.21 2020/01/23 17:23:03 uwe Exp $  */

/*
 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
 * Copyright (C) 1995, 1996 TooLs GmbH.
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by TooLs GmbH.
 * 4. The name of TooLs GmbH may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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 <sys/types.h>
#include <powerpc/oea/bat.h>
#include <powerpc/oea/spr.h>

#include <sys/bootblock.h>

int (*openfirmware)(void *);

                                /*
                                 * 32 KB of stack with 32 bytes overpad
                                 * (see below)
                                 */
int32_t __attribute__((aligned(16))) stack[8192 + 8];

struct shared_bbinfo bbinfo = {
        { MACPPC_BBINFO_MAGIC },
        0,
        SHARED_BBINFO_MAXBLOCKS,
        { 0 }
};

#ifndef DEFAULT_ENTRY_POINT
#define DEFAULT_ENTRY_POINT     0xE00000
#endif

void (*entry_point)(int, int, void *) = (void *)DEFAULT_ENTRY_POINT;


__asm(
"       .text                   \n"
"       .align 2                \n"
"       .globl  _start          \n"
"_start:                        \n"

"       lis     %r8,(_start)@ha \n"
"       addi    %r8,8,(_start)@l\n"
"       li      %r9,0x40        \n"     /* loop 64 times (for 2048 bytes of bootxx) */
"       mtctr   %r9             \n"
"                               \n"
"1:     dcbf    0,%r8           \n"
"       icbi    0,%r8           \n"
"       addi    %r8,%r8,0x20    \n"
"       bdnz    1b              \n"
"       sync                    \n"

"       li      %r0,0           \n"
"                               \n"     /* test for 601 cpu */
"       mfspr   %r9,287         \n"     /* mfpvbr %r9 PVR = 287 */
"       srwi    %r9,%r9,0x10    \n"
"       cmplwi  %r9,0x02        \n"     /* 601 cpu == 0x0001 */
"       blt     2f              \n"     /* skip over non-601 BAT setup */
"                               \n"
"       mtdbatu 3,%r0           \n"     /* non-601 BAT */
"       mtibatu 3,%r0           \n"
"       isync                   \n"
"       li      %r8,0x1ffe      \n"     /* map the lowest 256MB */
"       li      %r9,0x22        \n"     /* BAT_I */
"       mtdbatl 3,%r9           \n"
"       mtdbatu 3,%r8           \n"
"       mtibatl 3,%r9           \n"
"       mtibatu 3,%r8           \n"
"       isync                   \n"
"       b       3f              \n"
"                               \n"
"2:     mfmsr   %r8             \n"     /* 601 BAT */
"       mtmsr   %r0             \n"
"       isync                   \n"
"                               \n"
"       mtibatu 0,%r0           \n"
"       mtibatu 1,%r0           \n"
"       mtibatu 2,%r0           \n"
"       mtibatu 3,%r0           \n"
"                               \n"
"       li      %r9,0x7f        \n"
"       mtibatl 0,%r9           \n"
"       li      %r9,0x1a        \n"
"       mtibatu 0,%r9           \n"
"                               \n"
"       lis %r9,0x80            \n"
"       addi %r9,%r9,0x7f       \n"
"       mtibatl 1,%r9           \n"
"       lis %r9,0x80            \n"
"       addi %r9,%r9,0x1a       \n"
"       mtibatu 1,%r9           \n"
"                               \n"
"       lis %r9,0x100           \n"
"       addi %r9,%r9,0x7f       \n"
"       mtibatl 2,%r9           \n"
"       lis %r9,0x100           \n"
"       addi %r9,%r9,0x1a       \n"
"       mtibatu 2,%r9           \n"
"                               \n"
"       lis %r9,0x180           \n"
"       addi %r9,%r9,0x7f       \n"
"       mtibatl 3,%r9           \n"
"       lis %r9,0x180           \n"
"       addi %r9,%r9,0x1a       \n"
"       mtibatu 3,%r9           \n"
"                               \n"
"       isync                   \n"
"                               \n"
"       mtmsr   %r8             \n"
"       isync                   \n"
"                               \n"
        /*
         * setup 32 KB of stack with 32 bytes overpad (see above)
         */
"3:     lis     %r1,(stack+32768)@ha\n"
"       addi    %r1,%r1,(stack+32768)@l\n"
        /*
         * terminate the frame link chain,
         * clear by bytes to avoid ppc601 alignment exceptions
         */
"       stb     %r0,0(%r1)      \n"
"       stb     %r0,1(%r1)      \n"
"       stb     %r0,2(%r1)      \n"
"       stb     %r0,3(%r1)      \n"

"       b       startup         \n"
);


static inline int
OF_finddevice(char *name)
{
        static struct {
                char *name;
                int nargs;
                int nreturns;
                char *device;
                int phandle;
        } args = {
                "finddevice",
                1,
                1,
        };      
        
        args.device = name;
        openfirmware(&args);

        return args.phandle;
}

static inline int
OF_getprop(int handle, char *prop, void *buf, int buflen)
{
        static struct {
                char *name;
                int nargs;
                int nreturns;
                int phandle;
                char *prop;
                void *buf;
                int buflen;
                int size;
        } args = {
                "getprop",
                4,
                1,
        };
        
        args.phandle = handle;
        args.prop = prop;
        args.buf = buf;
        args.buflen = buflen;
        openfirmware(&args);

        return args.size;
}

static inline int
OF_open(char *dname)
{
        static struct {
                char *name;
                int nargs;
                int nreturns;
                char *dname;
                int handle;
        } args = {
                "open",
                1,
                1,
        };
        
        args.dname = dname;
        openfirmware(&args);

        return args.handle;
}

static inline int
OF_read(int handle, void *addr, int len)
{
        static struct {
                char *name;
                int nargs;
                int nreturns;
                int ihandle;
                void *addr;
                int len;
                int actual;
        } args = {
                "read",
                3,
                1,
        };

        args.ihandle = handle;
        args.addr = addr;
        args.len = len;
        openfirmware(&args);

        return args.actual;
}

static inline int
OF_seek(int handle, u_quad_t pos)
{
        static struct {
                char *name;
                int nargs;
                int nreturns;
                int handle;
                int poshi;
                int poslo;
                int status;
        } args = {
                "seek",
                3,
                1,
        };
        
        args.handle = handle;
        args.poshi = (int)(pos >> 32);
        args.poslo = (int)pos;
        openfirmware(&args);

        return args.status;
}

static inline int
OF_write(int handle, const void *addr, int len)
{
        static struct {
                char *name;
                int nargs;
                int nreturns;
                int ihandle;
                const void *addr;
                int len;
                int actual;
        } args = {
                "write",
                3,
                1,
        };

        args.ihandle = handle;
        args.addr = addr;
        args.len = len;
        openfirmware(&args);

        return args.actual;
}

int stdout;

static void
putstrn(const char *s, size_t n)
{
        OF_write(stdout, s, n);
}

#define putstr(x)       putstrn((x),sizeof(x)-1)
#define putc(x)         do { char __x = (x) ; putstrn(&__x, 1); } while (0)


void
startup(int arg1, int arg2, void *openfirm)
{
        int fd, blk, chosen, options, j;
        uint32_t cpuvers;
        size_t i;
        char *addr;
        char bootpath[128];

        __asm volatile ("mfpvr %0" : "=r"(cpuvers));
        cpuvers >>= 16;

        openfirmware = openfirm;

        chosen = OF_finddevice("/chosen");
        if (OF_getprop(chosen, "bootpath", bootpath, sizeof(bootpath)) == 1) {
                /*
                 * buggy firmware doesn't set bootpath...
                 */
                options = OF_finddevice("/options");
                OF_getprop(options, "boot-device", bootpath, sizeof(bootpath));
        }
        if (OF_getprop(chosen, "stdout", &stdout, sizeof(stdout))
            != sizeof(stdout))
                stdout = -1;

        /*
         * "scsi/sd@0:0" --> "scsi/sd@0"
         */
        for (i = 0; i < sizeof(bootpath); i++) {
                if (bootpath[i] == ':')
                        bootpath[i] = 0;
                if (bootpath[i] == 0)
                        break;
        }

        putstr("\r\nOF_open bootpath=");
        putstrn(bootpath, i);
        fd = OF_open(bootpath);

        addr = (char *)entry_point;
        putstr("\r\nread stage 2 blocks: ");
        for (j = 0; j < bbinfo.bbi_block_count; j++) {
                if ((blk = bbinfo.bbi_block_table[j]) == 0)
                        break;
                putc('0' + j % 10);
                OF_seek(fd, (u_quad_t)blk * 512);
                OF_read(fd, addr, bbinfo.bbi_block_size);
                addr += bbinfo.bbi_block_size;
        }
        putstr(". done!\r\nstarting stage 2...\r\n");

        if (cpuvers != MPC601) {
                /*
                 * enable D/I cache
                 */
                __asm(
                        "mtdbatu        3,%0\n\t"
                        "mtdbatl        3,%1\n\t"
                        "mtibatu        3,%0\n\t"
                        "mtibatl        3,%1\n\t"
                        "isync"
                ::      "r"(BATU(0, BAT_BL_256M, BAT_Vs)),
                        "r"(BATL(0, 0, BAT_PP_RW)));
        }

        entry_point(0, 0, openfirm);
        for (;;);                       /* just in case */
}