/*-
 * Copyright (c) 2000 Benno Rice <benno@jeamland.net>
 * Copyright (c) 2000 Stephane Potvin <sepotvin@videotron.ca>
 * 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 AUTHORS 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.
 */

#include <sys/endian.h>

#include <stand.h>
#include "openfirm.h"
#include "libofw.h"
#include "bootstrap.h"

#include <machine/asm.h>
#include <machine/psl.h>

#ifdef CAS
static int ppc64_autoload(void);
#endif

struct arch_switch      archsw = {              /* MI/MD interface boundary */
        .arch_getdev = ofw_getdev,
        .arch_copyin = ofw_copyin,
        .arch_copyout = ofw_copyout,
        .arch_readin = ofw_readin,
#ifdef CAS
        .arch_autoload = ppc64_autoload,
#else
        .arch_autoload = ofw_autoload,
#endif
};

uint32_t        acells, scells;

static char bootargs[128];

#define HEAP_SIZE       0x800000
static char heap[HEAP_SIZE]; // In BSS, so uses no space

#define OF_puts(fd, text) OF_write(fd, text, strlen(text))

static __inline register_t
mfmsr(void)
{
        register_t value;

        __asm __volatile ("mfmsr %0" : "=r"(value));

        return (value);
}

void
init_heap(void)
{
        bzero(heap, HEAP_SIZE);

        setheap(heap, (void *)((uintptr_t)heap + HEAP_SIZE));
}

uint64_t
memsize(void)
{
        phandle_t       memoryp;
        cell_t          reg[24];
        int             i, sz;
        uint64_t        memsz;

        memsz = 0;
        memoryp = OF_instance_to_package(memory);

        sz = OF_getencprop(memoryp, "reg", &reg[0], sizeof(reg));
        sz /= sizeof(reg[0]);

        for (i = 0; i < sz; i += (acells + scells)) {
                if (scells > 1)
                        memsz += (uint64_t)reg[i + acells] << 32;
                memsz += reg[i + acells + scells - 1];
        }

        return (memsz);
}

#ifdef CAS
extern int ppc64_cas(void);

static int
ppc64_autoload(void)
{
        const char *cas;

        if ((cas = getenv("cas")) && cas[0] == '1')
                if (ppc64_cas() != 0)
                        return (-1);
        return (ofw_autoload());
}
#endif

#if BYTE_ORDER == LITTLE_ENDIAN
/*
 * In Little-endian, we cannot just branch to the client interface. Since
 * the client interface is big endian, we have to rfid to it.
 * Likewise, when execution resumes, we are in the wrong endianness so
 * we must do a fixup before returning to the caller.
 */
static int (*openfirmware_entry)(void *);
extern int openfirmware_trampoline(void *buf, int (*cb)(void *));

/*
 * Wrapper to pass the real entry point to our trampoline.
 */
static int
openfirmware_docall(void *buf)
{
        return openfirmware_trampoline(buf, openfirmware_entry);
}
#endif

int
main(int (*openfirm)(void *))
{
        phandle_t       root;
        int             i;
        char            bootpath[64];
        char            *ch;
        int             bargc;
        char            **bargv;

        /*
         * Initialise the Open Firmware routines by giving them the entry point.
         */
#if BYTE_ORDER == LITTLE_ENDIAN
        /*
         * Use a trampoline entry point for endian fixups.
         */
        openfirmware_entry = openfirm;
        OF_init(openfirmware_docall);
#else
        OF_init(openfirm);
#endif

        root = OF_finddevice("/");

        scells = acells = 1;
        OF_getencprop(root, "#address-cells", &acells, sizeof(acells));
        OF_getencprop(root, "#size-cells", &scells, sizeof(scells));

        /*
         * Initialise the heap as early as possible.  Once this is done,
         * alloc() is usable. The stack is buried inside us, so this is
         * safe.
         */
        init_heap();

        /*
         * Set up console.
         */
        cons_probe();

#ifdef CAS
        setenv("cas", "1", 0);
#endif

        /* Set up currdev variable to have hooks in place. */
        env_setenv("currdev", EV_VOLATILE, "", gen_setcurrdev, env_nounset);

        devinit();

        printf("\n%s", bootprog_info);
        printf("Memory: %lldKB\n", memsize() / 1024);

        OF_getprop(chosen, "bootpath", bootpath, 64);
        ch = strchr(bootpath, ':');
        *ch = '\0';
        printf("Booted from: %s\n", bootpath);

        printf("\n");

        /*
         * Only parse the first bootarg if present. It should
         * be simple to handle extra arguments
         */
        OF_getprop(chosen, "bootargs", bootargs, sizeof(bootargs));
        bargc = 0;
        parse(&bargc, &bargv, bootargs);
        if (bargc == 1)
                env_setenv("currdev", EV_VOLATILE, bargv[0], gen_setcurrdev,
                    env_nounset);
        else
                env_setenv("currdev", EV_VOLATILE, bootpath,
                           gen_setcurrdev, env_nounset);
        env_setenv("loaddev", EV_VOLATILE, bootpath, env_noset,
            env_nounset);
        setenv("LINES", "24", 1);               /* optional */

        /*
         * On non-Apple hardware, where it works reliably, pass flattened
         * device trees to the kernel by default instead of OF CI pointers.
         * Apple hardware is the only virtual-mode OF implementation in
         * existence, so far as I am aware, so use that as a flag.
         */
        if (!(mfmsr() & PSL_DR))
                setenv("usefdt", "1", 1);

        interact();                             /* doesn't return */

        OF_exit();

        return 0;
}

COMMAND_SET(halt, "halt", "halt the system", command_halt);

static int
command_halt(int argc, char *argv[])
{

        OF_exit();
        return (CMD_OK);
}

COMMAND_SET(memmap, "memmap", "print memory map", command_memmap);

int
command_memmap(int argc, char **argv)
{

        ofw_memmap(acells);
        return (CMD_OK);
}