/*
 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
 * 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.
 */

#include <sys/cdefs.h>

/*
 * MD primitives supporting placement of module data
 *
 * XXX should check load address/size against memory top.
 */
#include <stand.h>
#include <sys/param.h>
#include <sys/multiboot2.h>
#include <sys/consplat.h>
#include <machine/metadata.h>
#include <machine/pc/bios.h>
#include "libi386.h"
#include "btxv86.h"
#include "bootstrap.h"

extern multiboot_tag_framebuffer_t gfx_fb;

/*
 * Verify the address is not in use by existing modules.
 */
static vm_offset_t
addr_verify(struct preloaded_file *fp, vm_offset_t addr, size_t size)
{
        vm_offset_t f_addr;

        while (fp != NULL) {
                f_addr = fp->f_addr;

                if ((f_addr <= addr) &&
                    (f_addr + fp->f_size >= addr)) {
                        return (0);
                }
                if ((f_addr >= addr) && (f_addr <= addr + size)) {
                        return (0);
                }
                fp = fp->f_next;
        }
        return (addr);
}

/*
 * Find smap entry above 1MB, able to contain size bytes from addr.
 */
static vm_offset_t
smap_find(struct bios_smap *smap, int smaplen, vm_offset_t addr, size_t size)
{
        int i;

        for (i = 0; i < smaplen; i++) {
                if (smap[i].type != SMAP_TYPE_MEMORY)
                        continue;

                /* We do not want address below 1MB. */
                if (smap[i].base < 0x100000)
                        continue;

                /* Do we fit into current entry? */
                if ((smap[i].base <= addr) &&
                    (smap[i].base + smap[i].length >= addr + size)) {
                        return (addr);
                }

                /* Do we fit into new entry? */
                if ((smap[i].base > addr) && (smap[i].length >= size)) {
                        return (smap[i].base);
                }
        }
        return (0);
}

/*
 * Find usable address for loading. The address for the kernel is fixed, as
 * it is determined by kernel linker map (dboot PT_LOAD address).
 * For modules, we need to consult smap, the module address has to be
 * aligned to page boundary and we have to fit into smap entry.
 */
vm_offset_t
i386_loadaddr(uint_t type, void *data, vm_offset_t addr)
{
        struct stat st;
        size_t size, smaplen;
        struct preloaded_file *fp, *mfp;
        struct file_metadata *md;
        struct bios_smap *smap;
        vm_offset_t off;

        /*
         * For now, assume we have memory for the kernel, the
         * required map is [1MB..) This assumption should be safe with x86 BIOS.
         */
        if (type == LOAD_KERN)
                return (addr);

        if (addr == 0)
                return (addr);  /* nothing to do */

        if (type == LOAD_ELF)
                return (0);     /* not supported */

        if (type == LOAD_MEM) {
                size = *(size_t *)data;
        } else {
                stat(data, &st);
                size = st.st_size;
        }

        /*
         * Find our kernel, from it we will find the smap and the list of
         * loaded modules.
         */
        fp = file_findfile(NULL, NULL);
        if (fp == NULL)
                return (0);
        md = file_findmetadata(fp, MODINFOMD_SMAP);
        if (md == NULL)
                return (0);

        smap = (struct bios_smap *)md->md_data;
        smaplen = md->md_size / sizeof (struct bios_smap);

        /* Start from the end of the kernel. */
        mfp = fp;
        do {
                if (mfp == NULL) {
                        off = roundup2(addr + 1, MULTIBOOT_MOD_ALIGN);
                } else {
                        off = roundup2(mfp->f_addr + mfp->f_size + 1,
                            MULTIBOOT_MOD_ALIGN);
                }
                /* Avoid possible framebuffer memory */
                if (plat_stdout_is_framebuffer()) {
                        vm_offset_t fb_addr;
                        size_t fb_size;

                        fb_addr = gfx_fb.framebuffer_common.framebuffer_addr;
                        fb_size = gfx_fb.framebuffer_common.framebuffer_height *
                            gfx_fb.framebuffer_common.framebuffer_pitch;

                        if ((off >= fb_addr && off <= fb_addr + fb_size) ||
                            (off + size >= fb_addr &&
                            off + size <= fb_addr + fb_size)) {
                                printf("\nSkipping framebuffer memory %#x "
                                    "size %#x\n", fb_addr, fb_size);
                                off = roundup2(fb_addr + fb_size + 1,
                                    MULTIBOOT_MOD_ALIGN);
                        }
                }
                off = smap_find(smap, smaplen, off, size);
                off = addr_verify(fp, off, size);
                if (off != 0)
                        break;

                if (mfp == NULL)
                        break;
                mfp = mfp->f_next;
        } while (off == 0);

        return (off);
}

ssize_t
i386_copyin(const void *src, vm_offset_t dest, const size_t len)
{
        if (dest + len >= memtop) {
                errno = EFBIG;
                return (-1);
        }

        bcopy(src, PTOV(dest), len);
        return (len);
}

ssize_t
i386_copyout(const vm_offset_t src, void *dest, const size_t len)
{
        if (src + len >= memtop) {
                errno = EFBIG;
                return (-1);
        }

        bcopy(PTOV(src), dest, len);
        return (len);
}


ssize_t
i386_readin(const int fd, vm_offset_t dest, const size_t len)
{
        if (dest + len >= memtop_copyin) {
                errno = EFBIG;
                return (-1);
        }

        return (read(fd, PTOV(dest), len));
}