preprocessor cleanup: __xpv

[unleashed.git] / arch / x86 / kernel / platform / i86pc / dboot / dboot_startkern.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2013 Joyent, Inc.  All rights reserved.
 */


#include <sys/types.h>
#include <sys/machparam.h>
#include <sys/x86_archext.h>
#include <sys/systm.h>
#include <sys/mach_mmu.h>
#include <sys/multiboot.h>
#include <sys/multiboot2.h>
#include <sys/multiboot2_impl.h>
#include <sys/sysmacros.h>
#include <sys/sha1.h>
#include <util/string.h>
#include <util/strtolctype.h>


extern multiboot_header_t mb_header;
extern uint32_t mb2_load_addr;
extern int have_cpuid(void);


#include <sys/inttypes.h>
#include <sys/bootinfo.h>
#include <sys/mach_mmu.h>
#include <sys/boot_console.h>

#include "dboot_asm.h"
#include "dboot_printf.h"
#include "dboot_xboot.h"
#include "dboot_elfload.h"

#define SHA1_ASCII_LENGTH       (SHA1_DIGEST_LENGTH * 2)

/*
 * This file contains code that runs to transition us from either a multiboot
 * compliant loader (32 bit non-paging) or a XPV domain loader to
 * regular kernel execution. Its task is to setup the kernel memory image
 * and page tables.
 *
 * The code executes as:
 *      - 32 bits under GRUB (for 32 or 64 bit Solaris)
 *      - a 32 bit program for the 32-bit PV hypervisor
 *      - a 64 bit program for the 64-bit PV hypervisor (at least for now)
 *
 * Under the PV hypervisor, we must create mappings for any memory beyond the
 * initial start of day allocation (such as the kernel itself).
 *
 * When on the metal, the mapping between maddr_t and paddr_t is 1:1.
 * Since we are running in real mode, so all such memory is accessible.
 */

/*
 * Standard bits used in PTE (page level) and PTP (internal levels)
 */
x86pte_t ptp_bits = PT_VALID | PT_REF | PT_WRITABLE | PT_USER;
x86pte_t pte_bits = PT_VALID | PT_REF | PT_WRITABLE | PT_MOD | PT_NOCONSIST;

/*
 * This is the target addresses (physical) where the kernel text and data
 * nucleus pages will be unpacked. On the hypervisor this is actually a
 * virtual address.
 */
paddr_t ktext_phys;
uint32_t ksize = 2 * FOUR_MEG;  /* kernel nucleus is 8Meg */

static uint64_t target_kernel_text;     /* value to use for KERNEL_TEXT */

/*
 * The stack is setup in assembler before entering startup_kernel()
 */
char stack_space[STACK_SIZE];

/*
 * Used to track physical memory allocation
 */
static paddr_t next_avail_addr = 0;


/*
 * If on the metal, then we have a multiboot loader.
 */
uint32_t mb_magic;                      /* magic from boot loader */
uint32_t mb_addr;                       /* multiboot info package from loader */
int multiboot_version;
multiboot_info_t *mb_info;
multiboot2_info_header_t *mb2_info;
multiboot_tag_mmap_t *mb2_mmap_tagp;
int num_entries;                        /* mmap entry count */
boolean_t num_entries_set;              /* is mmap entry count set */
uintptr_t load_addr;


/*
 * This contains information passed to the kernel
 */
struct xboot_info boot_info[2]; /* extra space to fix alignement for amd64 */
struct xboot_info *bi;

/*
 * Page table and memory stuff.
 */
static paddr_t max_mem;                 /* maximum memory address */

/*
 * Information about processor MMU
 */
int amd64_support = 0;
int largepage_support = 0;
int pae_support = 0;
int pge_support = 0;
int NX_support = 0;

/*
 * Low 32 bits of kernel entry address passed back to assembler.
 * When running a 64 bit kernel, the high 32 bits are 0xffffffff.
 */
uint32_t entry_addr_low;

/*
 * Memlists for the kernel. We shouldn't need a lot of these.
 */
#define MAX_MEMLIST (50)
struct boot_memlist memlists[MAX_MEMLIST];
uint_t memlists_used = 0;
struct boot_memlist pcimemlists[MAX_MEMLIST];
uint_t pcimemlists_used = 0;
struct boot_memlist rsvdmemlists[MAX_MEMLIST];
uint_t rsvdmemlists_used = 0;

/*
 * This should match what's in the bootloader.  It's arbitrary, but GRUB
 * in particular has limitations on how much space it can use before it
 * stops working properly.  This should be enough.
 */
struct boot_modules modules[MAX_BOOT_MODULES];
uint_t modules_used = 0;

typedef mb_memory_map_t mmap_t;

/*
 * Debugging macros
 */
uint_t prom_debug = 0;
uint_t map_debug = 0;

static char noname[2] = "-";

/*
 * Either hypervisor-specific or grub-specific code builds the initial
 * memlists. This code does the sort/merge/link for final use.
 */
static void
sort_physinstall(void)
{
        int i;
        int j;
        struct boot_memlist tmp;

        /*
         * Now sort the memlists, in case they weren't in order.
         * Yeah, this is a bubble sort; small, simple and easy to get right.
         */
        DBG_MSG("Sorting phys-installed list\n");
        for (j = memlists_used - 1; j > 0; --j) {
                for (i = 0; i < j; ++i) {
                        if (memlists[i].addr < memlists[i + 1].addr)
                                continue;
                        tmp = memlists[i];
                        memlists[i] = memlists[i + 1];
                        memlists[i + 1] = tmp;
                }
        }

        /*
         * Merge any memlists that don't have holes between them.
         */
        for (i = 0; i <= memlists_used - 1; ++i) {
                if (memlists[i].addr + memlists[i].size != memlists[i + 1].addr)
                        continue;

                if (prom_debug)
                        dboot_printf(
                            "merging mem segs %" PRIx64 "...%" PRIx64
                            " w/ %" PRIx64 "...%" PRIx64 "\n",
                            memlists[i].addr,
                            memlists[i].addr + memlists[i].size,
                            memlists[i + 1].addr,
                            memlists[i + 1].addr + memlists[i + 1].size);

                memlists[i].size += memlists[i + 1].size;
                for (j = i + 1; j < memlists_used - 1; ++j)
                        memlists[j] = memlists[j + 1];
                --memlists_used;
                DBG(memlists_used);
                --i;    /* after merging we need to reexamine, so do this */
        }

        if (prom_debug) {
                dboot_printf("\nFinal memlists:\n");
                for (i = 0; i < memlists_used; ++i) {
                        dboot_printf("\t%d: addr=%" PRIx64 " size=%"
                            PRIx64 "\n", i, memlists[i].addr, memlists[i].size);
                }
        }

        /*
         * link together the memlists with native size pointers
         */
        memlists[0].next = 0;
        memlists[0].prev = 0;
        for (i = 1; i < memlists_used; ++i) {
                memlists[i].prev = (native_ptr_t)(uintptr_t)(memlists + i - 1);
                memlists[i].next = 0;
                memlists[i - 1].next = (native_ptr_t)(uintptr_t)(memlists + i);
        }
        bi->bi_phys_install = (native_ptr_t)(uintptr_t)memlists;
        DBG(bi->bi_phys_install);
}

/*
 * build bios reserved memlists
 */
static void
build_rsvdmemlists(void)
{
        int i;

        rsvdmemlists[0].next = 0;
        rsvdmemlists[0].prev = 0;
        for (i = 1; i < rsvdmemlists_used; ++i) {
                rsvdmemlists[i].prev =
                    (native_ptr_t)(uintptr_t)(rsvdmemlists + i - 1);
                rsvdmemlists[i].next = 0;
                rsvdmemlists[i - 1].next =
                    (native_ptr_t)(uintptr_t)(rsvdmemlists + i);
        }
        bi->bi_rsvdmem = (native_ptr_t)(uintptr_t)rsvdmemlists;
        DBG(bi->bi_rsvdmem);
}


x86pte_t
get_pteval(paddr_t table, uint_t index)
{
        if (pae_support)
                return (((x86pte_t *)(uintptr_t)table)[index]);
        return (((x86pte32_t *)(uintptr_t)table)[index]);
}

/*ARGSUSED*/
void
set_pteval(paddr_t table, uint_t index, uint_t level, x86pte_t pteval)
{
        uintptr_t tab_addr = (uintptr_t)table;

        if (pae_support)
                ((x86pte_t *)tab_addr)[index] = pteval;
        else
                ((x86pte32_t *)tab_addr)[index] = (x86pte32_t)pteval;
        if (level == top_level && level == 2)
                reload_cr3();
}

paddr_t
make_ptable(x86pte_t *pteval, uint_t level)
{
        paddr_t new_table = (paddr_t)(uintptr_t)mem_alloc(MMU_PAGESIZE);

        if (level == top_level && level == 2)
                *pteval = pa_to_ma((uintptr_t)new_table) | PT_VALID;
        else
                *pteval = pa_to_ma((uintptr_t)new_table) | ptp_bits;


        if (map_debug)
                dboot_printf("new page table lvl=%d paddr=0x%lx ptp=0x%"
                    PRIx64 "\n", level, (ulong_t)new_table, *pteval);
        return (new_table);
}

x86pte_t *
map_pte(paddr_t table, uint_t index)
{
        return ((x86pte_t *)(uintptr_t)(table + index * pte_size));
}

/*
 * dump out the contents of page tables...
 */
static void
dump_tables(void)
{
        uint_t save_index[4];   /* for recursion */
        char *save_table[4];    /* for recursion */
        uint_t  l;
        uint64_t va;
        uint64_t pgsize;
        int index;
        int i;
        x86pte_t pteval;
        char *table;
        static char *tablist = "\t\t\t";
        char *tabs = tablist + 3 - top_level;
        uint_t pa, pa1;
#define maddr_t paddr_t

        dboot_printf("Finished pagetables:\n");
        table = (char *)(uintptr_t)top_page_table;
        l = top_level;
        va = 0;
        for (index = 0; index < ptes_per_table; ++index) {
                pgsize = 1ull << shift_amt[l];
                if (pae_support)
                        pteval = ((x86pte_t *)table)[index];
                else
                        pteval = ((x86pte32_t *)table)[index];
                if (pteval == 0)
                        goto next_entry;

                dboot_printf("%s %p[0x%x] = %" PRIx64 ", va=%" PRIx64,
                    tabs + l, (void *)table, index, (uint64_t)pteval, va);
                pa = ma_to_pa(pteval & MMU_PAGEMASK);
                dboot_printf(" physaddr=%x\n", pa);

                /*
                 * Don't try to walk hypervisor private pagetables
                 */
                if ((l > 1 || (l == 1 && (pteval & PT_PAGESIZE) == 0))) {
                        save_table[l] = table;
                        save_index[l] = index;
                        --l;
                        index = -1;
                        table = (char *)(uintptr_t)
                            ma_to_pa(pteval & MMU_PAGEMASK);
                        goto recursion;
                }

                /*
                 * shorten dump for consecutive mappings
                 */
                for (i = 1; index + i < ptes_per_table; ++i) {
                        if (pae_support)
                                pteval = ((x86pte_t *)table)[index + i];
                        else
                                pteval = ((x86pte32_t *)table)[index + i];
                        if (pteval == 0)
                                break;
                        pa1 = ma_to_pa(pteval & MMU_PAGEMASK);
                        if (pa1 != pa + i * pgsize)
                                break;
                }
                if (i > 2) {
                        dboot_printf("%s...\n", tabs + l);
                        va += pgsize * (i - 2);
                        index += i - 2;
                }
next_entry:
                va += pgsize;
                if (l == 3 && index == 256)     /* VA hole */
                        va = 0xffff800000000000ull;
recursion:
                ;
        }
        if (l < top_level) {
                ++l;
                index = save_index[l];
                table = save_table[l];
                goto recursion;
        }
}

/*
 * Add a mapping for the machine page at the given virtual address.
 */
static void
map_ma_at_va(maddr_t ma, native_ptr_t va, uint_t level)
{
        x86pte_t *ptep;
        x86pte_t pteval;

        pteval = ma | pte_bits;
        if (level > 0)
                pteval |= PT_PAGESIZE;
        if (va >= target_kernel_text && pge_support)
                pteval |= PT_GLOBAL;

        if (map_debug && ma != va)
                dboot_printf("mapping ma=0x%" PRIx64 " va=0x%" PRIx64
                    " pte=0x%" PRIx64 " l=%d\n",
                    (uint64_t)ma, (uint64_t)va, pteval, level);


        /*
         * Find the pte that will map this address. This creates any
         * missing intermediate level page tables
         */
        ptep = find_pte(va, NULL, level, 0);

        /*
         * When paravirtualized, we must use hypervisor calls to modify the
         * PTE, since paging is active. On real hardware we just write to
         * the pagetables which aren't in use yet.
         */
        if (va < 1024 * 1024)
                pteval |= PT_NOCACHE;           /* for video RAM */
        if (pae_support)
                *ptep = pteval;
        else
                *((x86pte32_t *)ptep) = (x86pte32_t)pteval;
}

/*
 * Add a mapping for the physical page at the given virtual address.
 */
static void
map_pa_at_va(paddr_t pa, native_ptr_t va, uint_t level)
{
        map_ma_at_va(pa_to_ma(pa), va, level);
}

/*
 * This is called to remove start..end from the
 * possible range of PCI addresses.
 */
const uint64_t pci_lo_limit = 0x00100000ul;
const uint64_t pci_hi_limit = 0xfff00000ul;
static void
exclude_from_pci(uint64_t start, uint64_t end)
{
        int i;
        int j;
        struct boot_memlist *ml;

        for (i = 0; i < pcimemlists_used; ++i) {
                ml = &pcimemlists[i];

                /* delete the entire range? */
                if (start <= ml->addr && ml->addr + ml->size <= end) {
                        --pcimemlists_used;
                        for (j = i; j < pcimemlists_used; ++j)
                                pcimemlists[j] = pcimemlists[j + 1];
                        --i;    /* to revisit the new one at this index */
                }

                /* split a range? */
                else if (ml->addr < start && end < ml->addr + ml->size) {

                        ++pcimemlists_used;
                        if (pcimemlists_used > MAX_MEMLIST)
                                dboot_panic("too many pcimemlists");

                        for (j = pcimemlists_used - 1; j > i; --j)
                                pcimemlists[j] = pcimemlists[j - 1];
                        ml->size = start - ml->addr;

                        ++ml;
                        ml->size = (ml->addr + ml->size) - end;
                        ml->addr = end;
                        ++i;    /* skip on to next one */
                }

                /* cut memory off the start? */
                else if (ml->addr < end && end < ml->addr + ml->size) {
                        ml->size -= end - ml->addr;
                        ml->addr = end;
                }

                /* cut memory off the end? */
                else if (ml->addr <= start && start < ml->addr + ml->size) {
                        ml->size = start - ml->addr;
                }
        }
}

/*
 * During memory allocation, find the highest address not used yet.
 */
static void
check_higher(paddr_t a)
{
        if (a < next_avail_addr)
                return;
        next_avail_addr = RNDUP(a + 1, MMU_PAGESIZE);
        DBG(next_avail_addr);
}

static int
dboot_loader_mmap_entries(void)
{
        if (num_entries_set == B_TRUE)
                return (num_entries);

        switch (multiboot_version) {
        case 1:
                DBG(mb_info->flags);
                if (mb_info->flags & 0x40) {
                        mb_memory_map_t *mmap;

                        DBG(mb_info->mmap_addr);
                        DBG(mb_info->mmap_length);
                        check_higher(mb_info->mmap_addr + mb_info->mmap_length);

                        for (mmap = (mb_memory_map_t *)mb_info->mmap_addr;
                            (uint32_t)mmap < mb_info->mmap_addr +
                            mb_info->mmap_length;
                            mmap = (mb_memory_map_t *)((uint32_t)mmap +
                            mmap->size + sizeof (mmap->size)))
                                ++num_entries;

                        num_entries_set = B_TRUE;
                }
                break;
        case 2:
                num_entries_set = B_TRUE;
                num_entries = dboot_multiboot2_mmap_nentries(mb2_info,
                    mb2_mmap_tagp);
                break;
        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (num_entries);
}

static uint32_t
dboot_loader_mmap_get_type(int index)
{
        mb_memory_map_t *mp, *mpend;
        int i;

        switch (multiboot_version) {
        case 1:
                mp = (mb_memory_map_t *)mb_info->mmap_addr;
                mpend = (mb_memory_map_t *)
                    (mb_info->mmap_addr + mb_info->mmap_length);

                for (i = 0; mp < mpend && i != index; i++)
                        mp = (mb_memory_map_t *)((uint32_t)mp + mp->size +
                            sizeof (mp->size));
                if (mp >= mpend) {
                        dboot_panic("dboot_loader_mmap_get_type(): index "
                            "out of bounds: %d\n", index);
                }
                return (mp->type);

        case 2:
                return (dboot_multiboot2_mmap_get_type(mb2_info,
                    mb2_mmap_tagp, index));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

static uint64_t
dboot_loader_mmap_get_base(int index)
{
        mb_memory_map_t *mp, *mpend;
        int i;

        switch (multiboot_version) {
        case 1:
                mp = (mb_memory_map_t *)mb_info->mmap_addr;
                mpend = (mb_memory_map_t *)
                    (mb_info->mmap_addr + mb_info->mmap_length);

                for (i = 0; mp < mpend && i != index; i++)
                        mp = (mb_memory_map_t *)((uint32_t)mp + mp->size +
                            sizeof (mp->size));
                if (mp >= mpend) {
                        dboot_panic("dboot_loader_mmap_get_base(): index "
                            "out of bounds: %d\n", index);
                }
                return (((uint64_t)mp->base_addr_high << 32) +
                    (uint64_t)mp->base_addr_low);

        case 2:
                return (dboot_multiboot2_mmap_get_base(mb2_info,
                    mb2_mmap_tagp, index));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

static uint64_t
dboot_loader_mmap_get_length(int index)
{
        mb_memory_map_t *mp, *mpend;
        int i;

        switch (multiboot_version) {
        case 1:
                mp = (mb_memory_map_t *)mb_info->mmap_addr;
                mpend = (mb_memory_map_t *)
                    (mb_info->mmap_addr + mb_info->mmap_length);

                for (i = 0; mp < mpend && i != index; i++)
                        mp = (mb_memory_map_t *)((uint32_t)mp + mp->size +
                            sizeof (mp->size));
                if (mp >= mpend) {
                        dboot_panic("dboot_loader_mmap_get_length(): index "
                            "out of bounds: %d\n", index);
                }
                return (((uint64_t)mp->length_high << 32) +
                    (uint64_t)mp->length_low);

        case 2:
                return (dboot_multiboot2_mmap_get_length(mb2_info,
                    mb2_mmap_tagp, index));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

static void
build_pcimemlists(void)
{
        uint64_t page_offset = MMU_PAGEOFFSET;  /* needs to be 64 bits */
        uint64_t start;
        uint64_t end;
        int i, num;

        /*
         * initialize
         */
        pcimemlists[0].addr = pci_lo_limit;
        pcimemlists[0].size = pci_hi_limit - pci_lo_limit;
        pcimemlists_used = 1;

        num = dboot_loader_mmap_entries();
        /*
         * Fill in PCI memlists.
         */
        for (i = 0; i < num; ++i) {
                start = dboot_loader_mmap_get_base(i);
                end = start + dboot_loader_mmap_get_length(i);

                if (prom_debug)
                        dboot_printf("\ttype: %d %" PRIx64 "..%"
                            PRIx64 "\n", dboot_loader_mmap_get_type(i),
                            start, end);

                /*
                 * page align start and end
                 */
                start = (start + page_offset) & ~page_offset;
                end &= ~page_offset;
                if (end <= start)
                        continue;

                exclude_from_pci(start, end);
        }

        /*
         * Finish off the pcimemlist
         */
        if (prom_debug) {
                for (i = 0; i < pcimemlists_used; ++i) {
                        dboot_printf("pcimemlist entry 0x%" PRIx64 "..0x%"
                            PRIx64 "\n", pcimemlists[i].addr,
                            pcimemlists[i].addr + pcimemlists[i].size);
                }
        }
        pcimemlists[0].next = 0;
        pcimemlists[0].prev = 0;
        for (i = 1; i < pcimemlists_used; ++i) {
                pcimemlists[i].prev =
                    (native_ptr_t)(uintptr_t)(pcimemlists + i - 1);
                pcimemlists[i].next = 0;
                pcimemlists[i - 1].next =
                    (native_ptr_t)(uintptr_t)(pcimemlists + i);
        }
        bi->bi_pcimem = (native_ptr_t)(uintptr_t)pcimemlists;
        DBG(bi->bi_pcimem);
}


static void
dboot_multiboot1_xboot_consinfo(void)
{
}

static void
dboot_multiboot2_xboot_consinfo(void)
{
}

static int
dboot_multiboot_modcount(void)
{
        switch (multiboot_version) {
        case 1:
                return (mb_info->mods_count);

        case 2:
                return (dboot_multiboot2_modcount(mb2_info));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

static uint32_t
dboot_multiboot_modstart(int index)
{
        switch (multiboot_version) {
        case 1:
                return (((mb_module_t *)mb_info->mods_addr)[index].mod_start);

        case 2:
                return (dboot_multiboot2_modstart(mb2_info, index));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

static uint32_t
dboot_multiboot_modend(int index)
{
        switch (multiboot_version) {
        case 1:
                return (((mb_module_t *)mb_info->mods_addr)[index].mod_end);

        case 2:
                return (dboot_multiboot2_modend(mb2_info, index));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

static char *
dboot_multiboot_modcmdline(int index)
{
        switch (multiboot_version) {
        case 1:
                return ((char *)((mb_module_t *)
                    mb_info->mods_addr)[index].mod_name);

        case 2:
                return (dboot_multiboot2_modcmdline(mb2_info, index));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (0);
}

/*
 * Find the environment module for console setup.
 * Since we need the console to print early boot messages, the console is set up
 * before anything else and therefore we need to pick up the environment module
 * early too.
 *
 * Note, we just will search for and if found, will pass the env
 * module to console setup, the proper module list processing will happen later.
 */
static void
dboot_find_env(void)
{
        int i, modcount;
        uint32_t mod_start, mod_end;
        char *cmdline;

        modcount = dboot_multiboot_modcount();

        for (i = 0; i < modcount; ++i) {
                cmdline = dboot_multiboot_modcmdline(i);
                if (cmdline == NULL)
                        continue;

                if (strstr(cmdline, "type=environment") == NULL)
                        continue;

                mod_start = dboot_multiboot_modstart(i);
                mod_end = dboot_multiboot_modend(i);
                modules[0].bm_addr = mod_start;
                modules[0].bm_size = mod_end - mod_start;
                modules[0].bm_name = (uintptr_t)NULL;
                modules[0].bm_hash = (uintptr_t)NULL;
                modules[0].bm_type = BMT_ENV;
                bi->bi_modules = (native_ptr_t)(uintptr_t)modules;
                bi->bi_module_cnt = 1;
                return;
        }
}

static boolean_t
dboot_multiboot_basicmeminfo(uint32_t *lower, uint32_t *upper)
{
        boolean_t rv = B_FALSE;

        switch (multiboot_version) {
        case 1:
                if (mb_info->flags & 0x01) {
                        *lower = mb_info->mem_lower;
                        *upper = mb_info->mem_upper;
                        rv = B_TRUE;
                }
                break;

        case 2:
                return (dboot_multiboot2_basicmeminfo(mb2_info, lower, upper));

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        return (rv);
}

static uint8_t
dboot_a2h(char v)
{
        if (v >= 'a')
                return (v - 'a' + 0xa);
        else if (v >= 'A')
                return (v - 'A' + 0xa);
        else if (v >= '0')
                return (v - '0');
        else
                dboot_panic("bad ASCII hex character %c\n", v);

        return (0);
}

static void
digest_a2h(const char *ascii, uint8_t *digest)
{
        unsigned int i;

        for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
                digest[i] = dboot_a2h(ascii[i * 2]) << 4;
                digest[i] |= dboot_a2h(ascii[i * 2 + 1]);
        }
}

/*
 * Generate a SHA-1 hash of the first len bytes of image, and compare it with
 * the ASCII-format hash found in the 40-byte buffer at ascii.  If they
 * match, return 0, otherwise -1.  This works only for images smaller than
 * 4 GB, which should not be a problem.
 */
static int
check_image_hash(uint_t midx)
{
        const char *ascii;
        const void *image;
        size_t len;
        SHA1_CTX ctx;
        uint8_t digest[SHA1_DIGEST_LENGTH];
        uint8_t baseline[SHA1_DIGEST_LENGTH];
        unsigned int i;

        ascii = (const char *)(uintptr_t)modules[midx].bm_hash;
        image = (const void *)(uintptr_t)modules[midx].bm_addr;
        len = (size_t)modules[midx].bm_size;

        digest_a2h(ascii, baseline);

        SHA1Init(&ctx);
        SHA1Update(&ctx, image, len);
        SHA1Final(digest, &ctx);

        for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
                if (digest[i] != baseline[i])
                        return (-1);
        }

        return (0);
}

static const char *
type_to_str(boot_module_type_t type)
{
        switch (type) {
        case BMT_ROOTFS:
                return ("rootfs");
        case BMT_FILE:
                return ("file");
        case BMT_HASH:
                return ("hash");
        case BMT_ENV:
                return ("environment");
        default:
                return ("unknown");
        }
}

static void
check_images(void)
{
        uint_t i;
        char displayhash[SHA1_ASCII_LENGTH + 1];

        for (i = 0; i < modules_used; i++) {
                if (prom_debug) {
                        dboot_printf("module #%d: name %s type %s "
                            "addr %lx size %lx\n",
                            i, (char *)(uintptr_t)modules[i].bm_name,
                            type_to_str(modules[i].bm_type),
                            (ulong_t)modules[i].bm_addr,
                            (ulong_t)modules[i].bm_size);
                }

                if (modules[i].bm_type == BMT_HASH ||
                    modules[i].bm_hash == (uintptr_t)NULL) {
                        DBG_MSG("module has no hash; skipping check\n");
                        continue;
                }
                (void) memcpy(displayhash,
                    (void *)(uintptr_t)modules[i].bm_hash,
                    SHA1_ASCII_LENGTH);
                displayhash[SHA1_ASCII_LENGTH] = '\0';
                if (prom_debug) {
                        dboot_printf("checking expected hash [%s]: ",
                            displayhash);
                }

                if (check_image_hash(i) != 0)
                        dboot_panic("hash mismatch!\n");
                else
                        DBG_MSG("OK\n");
        }
}

/*
 * Determine the module's starting address, size, name, and type, and fill the
 * boot_modules structure.  This structure is used by the bop code, except for
 * hashes which are checked prior to transferring control to the kernel.
 */
static void
process_module(int midx)
{
        uint32_t mod_start = dboot_multiboot_modstart(midx);
        uint32_t mod_end = dboot_multiboot_modend(midx);
        char *cmdline = dboot_multiboot_modcmdline(midx);
        char *p, *q;

        check_higher(mod_end);
        if (prom_debug) {
                dboot_printf("\tmodule #%d: '%s' at 0x%lx, end 0x%lx\n",
                    midx, cmdline, (ulong_t)mod_start, (ulong_t)mod_end);
        }

        if (mod_start > mod_end) {
                dboot_panic("module #%d: module start address 0x%lx greater "
                    "than end address 0x%lx", midx,
                    (ulong_t)mod_start, (ulong_t)mod_end);
        }

        /*
         * A brief note on lengths and sizes: GRUB, for reasons unknown, passes
         * the address of the last valid byte in a module plus 1 as mod_end.
         * This is of course a bug; the multiboot specification simply states
         * that mod_start and mod_end "contain the start and end addresses of
         * the boot module itself" which is pretty obviously not what GRUB is
         * doing.  However, fixing it requires that not only this code be
         * changed but also that other code consuming this value and values
         * derived from it be fixed, and that the kernel and GRUB must either
         * both have the bug or neither.  While there are a lot of combinations
         * that will work, there are also some that won't, so for simplicity
         * we'll just cope with the bug.  That means we won't actually hash the
         * byte at mod_end, and we will expect that mod_end for the hash file
         * itself is one greater than some multiple of 41 (40 bytes of ASCII
         * hash plus a newline for each module).  We set bm_size to the true
         * correct number of bytes in each module, achieving exactly this.
         */

        modules[midx].bm_addr = mod_start;
        modules[midx].bm_size = mod_end - mod_start;
        modules[midx].bm_name = (native_ptr_t)(uintptr_t)cmdline;
        modules[midx].bm_hash = (uintptr_t)NULL;
        modules[midx].bm_type = BMT_FILE;

        if (cmdline == NULL) {
                modules[midx].bm_name = (native_ptr_t)(uintptr_t)noname;
                return;
        }

        p = cmdline;
        modules[midx].bm_name =
            (native_ptr_t)(uintptr_t)strsep(&p, " \t\f\n\r");

        while (p != NULL) {
                q = strsep(&p, " \t\f\n\r");
                if (strncmp(q, "name=", 5) == 0) {
                        if (q[5] != '\0' && !isspace(q[5])) {
                                modules[midx].bm_name =
                                    (native_ptr_t)(uintptr_t)(q + 5);
                        }
                        continue;
                }

                if (strncmp(q, "type=", 5) == 0) {
                        if (q[5] == '\0' || isspace(q[5]))
                                continue;
                        q += 5;
                        if (strcmp(q, "rootfs") == 0) {
                                modules[midx].bm_type = BMT_ROOTFS;
                        } else if (strcmp(q, "hash") == 0) {
                                modules[midx].bm_type = BMT_HASH;
                        } else if (strcmp(q, "environment") == 0) {
                                modules[midx].bm_type = BMT_ENV;
                        } else if (strcmp(q, "file") != 0) {
                                dboot_printf("\tmodule #%d: unknown module "
                                    "type '%s'; defaulting to 'file'",
                                    midx, q);
                        }
                        continue;
                }

                if (strncmp(q, "hash=", 5) == 0) {
                        if (q[5] != '\0' && !isspace(q[5])) {
                                modules[midx].bm_hash =
                                    (native_ptr_t)(uintptr_t)(q + 5);
                        }
                        continue;
                }

                dboot_printf("ignoring unknown option '%s'\n", q);
        }
}

/*
 * Backward compatibility: if there are exactly one or two modules, both
 * of type 'file' and neither with an embedded hash value, we have been
 * given the legacy style modules.  In this case we need to treat the first
 * module as a rootfs and the second as a hash referencing that module.
 * Otherwise, even if the configuration is invalid, we assume that the
 * operator knows what he's doing or at least isn't being bitten by this
 * interface change.
 */
static void
fixup_modules(void)
{
        if (modules_used == 0 || modules_used > 2)
                return;

        if (modules[0].bm_type != BMT_FILE ||
            modules_used > 1 && modules[1].bm_type != BMT_FILE) {
                return;
        }

        if (modules[0].bm_hash != (uintptr_t)NULL ||
            modules_used > 1 && modules[1].bm_hash != (uintptr_t)NULL) {
                return;
        }

        modules[0].bm_type = BMT_ROOTFS;
        if (modules_used > 1) {
                modules[1].bm_type = BMT_HASH;
                modules[1].bm_name = modules[0].bm_name;
        }
}

/*
 * For modules that do not have assigned hashes but have a separate hash module,
 * find the assigned hash module and set the primary module's bm_hash to point
 * to the hash data from that module.  We will then ignore modules of type
 * BMT_HASH from this point forward.
 */
static void
assign_module_hashes(void)
{
        uint_t i, j;

        for (i = 0; i < modules_used; i++) {
                if (modules[i].bm_type == BMT_HASH ||
                    modules[i].bm_hash != (uintptr_t)NULL) {
                        continue;
                }

                for (j = 0; j < modules_used; j++) {
                        if (modules[j].bm_type != BMT_HASH ||
                            strcmp((char *)(uintptr_t)modules[j].bm_name,
                            (char *)(uintptr_t)modules[i].bm_name) != 0) {
                                continue;
                        }

                        if (modules[j].bm_size < SHA1_ASCII_LENGTH) {
                                dboot_printf("Short hash module of length "
                                    "0x%lx bytes; ignoring\n",
                                    (ulong_t)modules[j].bm_size);
                        } else {
                                modules[i].bm_hash = modules[j].bm_addr;
                        }
                        break;
                }
        }
}

/*
 * Walk through the module information finding the last used address.
 * The first available address will become the top level page table.
 */
static void
dboot_process_modules(void)
{
        int i, modcount;
        extern char _end[];

        DBG_MSG("\nFinding Modules\n");
        modcount = dboot_multiboot_modcount();
        if (modcount > MAX_BOOT_MODULES) {
                dboot_panic("Too many modules (%d) -- the maximum is %d.",
                    modcount, MAX_BOOT_MODULES);
        }
        /*
         * search the modules to find the last used address
         * we'll build the module list while we're walking through here
         */
        check_higher((paddr_t)(uintptr_t)&_end);
        for (i = 0; i < modcount; ++i) {
                process_module(i);
                modules_used++;
        }
        bi->bi_modules = (native_ptr_t)(uintptr_t)modules;
        DBG(bi->bi_modules);
        bi->bi_module_cnt = modcount;
        DBG(bi->bi_module_cnt);

        fixup_modules();
        assign_module_hashes();
        check_images();
}

/*
 * We then build the phys_install memlist from the multiboot information.
 */
static void
dboot_process_mmap(void)
{
        uint64_t start;
        uint64_t end;
        uint64_t page_offset = MMU_PAGEOFFSET;  /* needs to be 64 bits */
        uint32_t lower, upper;
        int i, mmap_entries;

        /*
         * Walk through the memory map from multiboot and build our memlist
         * structures. Note these will have native format pointers.
         */
        DBG_MSG("\nFinding Memory Map\n");
        num_entries = 0;
        num_entries_set = B_FALSE;
        max_mem = 0;
        if ((mmap_entries = dboot_loader_mmap_entries()) > 0) {
                for (i = 0; i < mmap_entries; i++) {
                        uint32_t type = dboot_loader_mmap_get_type(i);
                        start = dboot_loader_mmap_get_base(i);
                        end = start + dboot_loader_mmap_get_length(i);

                        if (prom_debug)
                                dboot_printf("\ttype: %d %" PRIx64 "..%"
                                    PRIx64 "\n", type, start, end);

                        /*
                         * page align start and end
                         */
                        start = (start + page_offset) & ~page_offset;
                        end &= ~page_offset;
                        if (end <= start)
                                continue;

                        /*
                         * only type 1 is usable RAM
                         */
                        switch (type) {
                        case 1:
                                if (end > max_mem)
                                        max_mem = end;
                                memlists[memlists_used].addr = start;
                                memlists[memlists_used].size = end - start;
                                ++memlists_used;
                                if (memlists_used > MAX_MEMLIST)
                                        dboot_panic("too many memlists");
                                break;
                        case 2:
                                rsvdmemlists[rsvdmemlists_used].addr = start;
                                rsvdmemlists[rsvdmemlists_used].size =
                                    end - start;
                                ++rsvdmemlists_used;
                                if (rsvdmemlists_used > MAX_MEMLIST)
                                        dboot_panic("too many rsvdmemlists");
                                break;
                        default:
                                continue;
                        }
                }
                build_pcimemlists();
        } else if (dboot_multiboot_basicmeminfo(&lower, &upper)) {
                DBG(lower);
                memlists[memlists_used].addr = 0;
                memlists[memlists_used].size = lower * 1024;
                ++memlists_used;
                DBG(upper);
                memlists[memlists_used].addr = 1024 * 1024;
                memlists[memlists_used].size = upper * 1024;
                ++memlists_used;

                /*
                 * Old platform - assume I/O space at the end of memory.
                 */
                pcimemlists[0].addr = (upper * 1024) + (1024 * 1024);
                pcimemlists[0].size = pci_hi_limit - pcimemlists[0].addr;
                pcimemlists[0].next = 0;
                pcimemlists[0].prev = 0;
                bi->bi_pcimem = (native_ptr_t)(uintptr_t)pcimemlists;
                DBG(bi->bi_pcimem);
        } else {
                dboot_panic("No memory info from boot loader!!!");
        }

        /*
         * finish processing the physinstall list
         */
        sort_physinstall();

        /*
         * build bios reserved mem lists
         */
        build_rsvdmemlists();
}

/*
 * The highest address is used as the starting point for dboot's simple
 * memory allocator.
 *
 * Finding the highest address in case of Multiboot 1 protocol is
 * quite painful in the sense that some information provided by
 * the multiboot info structure points to BIOS data, and some to RAM.
 *
 * The module list was processed and checked already by dboot_process_modules(),
 * so we will check the command line string and the memory map.
 *
 * This list of to be checked items is based on our current knowledge of
 * allocations made by grub1 and will need to be reviewed if there
 * are updates about the information provided by Multiboot 1.
 *
 * In the case of the Multiboot 2, our life is much simpler, as the MB2
 * information tag list is one contiguous chunk of memory.
 */
static paddr_t
dboot_multiboot1_highest_addr(void)
{
        paddr_t addr = (uintptr_t)NULL;
        char *cmdl = (char *)mb_info->cmdline;

        if (mb_info->flags & MB_INFO_CMDLINE)
                addr = ((paddr_t)((uintptr_t)cmdl + strlen(cmdl) + 1));

        if (mb_info->flags & MB_INFO_MEM_MAP)
                addr = MAX(addr,
                    ((paddr_t)(mb_info->mmap_addr + mb_info->mmap_length)));
        return (addr);
}

static void
dboot_multiboot_highest_addr(void)
{
        paddr_t addr;

        switch (multiboot_version) {
        case 1:
                addr = dboot_multiboot1_highest_addr();
                if (addr != (uintptr_t)NULL)
                        check_higher(addr);
                break;
        case 2:
                addr = dboot_multiboot2_highest_addr(mb2_info);
                if (addr != (uintptr_t)NULL)
                        check_higher(addr);
                break;
        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
}

/*
 * Walk the boot loader provided information and find the highest free address.
 */
static void
init_mem_alloc(void)
{
        DBG_MSG("Entered init_mem_alloc()\n");
        dboot_process_modules();
        dboot_process_mmap();
        dboot_multiboot_highest_addr();
}

static void
dboot_multiboot_get_fwtables(void)
{
        multiboot_tag_new_acpi_t *nacpitagp;
        multiboot_tag_old_acpi_t *oacpitagp;

        /* no fw tables from multiboot 1 */
        if (multiboot_version != 2)
                return;

        /* only provide SMBIOS pointer in case of UEFI */
        bi->bi_smbios = (uintptr_t)NULL;

        nacpitagp = (multiboot_tag_new_acpi_t *)
            dboot_multiboot2_find_tag(mb2_info,
            MULTIBOOT_TAG_TYPE_ACPI_NEW);
        oacpitagp = (multiboot_tag_old_acpi_t *)
            dboot_multiboot2_find_tag(mb2_info,
            MULTIBOOT_TAG_TYPE_ACPI_OLD);

        if (nacpitagp != NULL) {
                bi->bi_acpi_rsdp = (native_ptr_t)(uintptr_t)
                    &nacpitagp->mb_rsdp[0];
        } else if (oacpitagp != NULL) {
                bi->bi_acpi_rsdp = (native_ptr_t)(uintptr_t)
                    &oacpitagp->mb_rsdp[0];
        } else {
                bi->bi_acpi_rsdp = (uintptr_t)NULL;
        }
}

/*
 * Simple memory allocator, allocates aligned physical memory.
 * Note that startup_kernel() only allocates memory, never frees.
 * Memory usage just grows in an upward direction.
 */
static void *
do_mem_alloc(uint32_t size, uint32_t align)
{
        uint_t i;
        uint64_t best;
        uint64_t start;
        uint64_t end;

        /*
         * make sure size is a multiple of pagesize
         */
        size = RNDUP(size, MMU_PAGESIZE);
        next_avail_addr = RNDUP(next_avail_addr, align);

        /*
         * XXPV fixme joe
         *
         * a really large bootarchive that causes you to run out of memory
         * may cause this to blow up
         */
        /* LINTED E_UNEXPECTED_UINT_PROMOTION */
        best = (uint64_t)-size;
        for (i = 0; i < memlists_used; ++i) {
                start = memlists[i].addr;
                end = start + memlists[i].size;

                /*
                 * did we find the desired address?
                 */
                if (start <= next_avail_addr && next_avail_addr + size <= end) {
                        best = next_avail_addr;
                        goto done;
                }

                /*
                 * if not is this address the best so far?
                 */
                if (start > next_avail_addr && start < best &&
                    RNDUP(start, align) + size <= end)
                        best = RNDUP(start, align);
        }

        /*
         * We didn't find exactly the address we wanted, due to going off the
         * end of a memory region. Return the best found memory address.
         */
done:
        next_avail_addr = best + size;
        (void) memset((void *)(uintptr_t)best, 0, size);
        return ((void *)(uintptr_t)best);
}

void *
mem_alloc(uint32_t size)
{
        return (do_mem_alloc(size, MMU_PAGESIZE));
}


/*
 * Build page tables to map all of memory used so far as well as the kernel.
 */
static void
build_page_tables(void)
{
        uint32_t psize;
        uint32_t level;
        uint32_t off;
        uint64_t start;
        uint32_t i;
        uint64_t end;

        /*
         * If we're on metal, we need to create the top level pagetable.
         */
        top_page_table = (paddr_t)(uintptr_t)mem_alloc(MMU_PAGESIZE);
        DBG((uintptr_t)top_page_table);

        /*
         * Determine if we'll use large mappings for kernel, then map it.
         */
        if (largepage_support) {
                psize = lpagesize;
                level = 1;
        } else {
                psize = MMU_PAGESIZE;
                level = 0;
        }

        DBG_MSG("Mapping kernel\n");
        DBG(ktext_phys);
        DBG(target_kernel_text);
        DBG(ksize);
        DBG(psize);
        for (off = 0; off < ksize; off += psize)
                map_pa_at_va(ktext_phys + off, target_kernel_text + off, level);

        /*
         * The kernel will need a 1 page window to work with page tables
         */
        bi->bi_pt_window = (uintptr_t)mem_alloc(MMU_PAGESIZE);
        DBG(bi->bi_pt_window);
        bi->bi_pte_to_pt_window =
            (uintptr_t)find_pte(bi->bi_pt_window, NULL, 0, 0);
        DBG(bi->bi_pte_to_pt_window);


        /*
         * We need 1:1 mappings for the lower 1M of memory to access
         * BIOS tables used by a couple of drivers during boot.
         *
         * The following code works because our simple memory allocator
         * only grows usage in an upwards direction.
         *
         * Note that by this point in boot some mappings for low memory
         * may already exist because we've already accessed device in low
         * memory.  (Specifically the video frame buffer and keyboard
         * status ports.)  If we're booting on raw hardware then GRUB
         * created these mappings for us.  If we're booting under a
         * hypervisor then we went ahead and remapped these devices into
         * memory allocated within dboot itself.
         */
        if (map_debug)
                dboot_printf("1:1 map pa=0..1Meg\n");
        for (start = 0; start < 1024 * 1024; start += MMU_PAGESIZE) {
                map_pa_at_va(start, start, 0);
        }

        for (i = 0; i < memlists_used; ++i) {
                start = memlists[i].addr;

                end = start + memlists[i].size;

                if (map_debug)
                        dboot_printf("1:1 map pa=%" PRIx64 "..%" PRIx64 "\n",
                            start, end);
                while (start < end && start < next_avail_addr) {
                        map_pa_at_va(start, start, 0);
                        start += MMU_PAGESIZE;
                }
        }

        DBG_MSG("\nPage tables constructed\n");
}

static void
dboot_init_xboot_consinfo(void)
{
        uintptr_t addr;
        /*
         * boot info must be 16 byte aligned for 64 bit kernel ABI
         */
        addr = (uintptr_t)boot_info;
        addr = (addr + 0xf) & ~0xf;
        bi = (struct xboot_info *)addr;

        switch (multiboot_version) {
        case 1:
                dboot_multiboot1_xboot_consinfo();
                break;
        case 2:
                dboot_multiboot2_xboot_consinfo();
                break;
        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        /*
         * Lookup environment module for the console. Complete module list
         * will be built after console setup.
         */
        dboot_find_env();
}

/*
 * Set up basic data from the boot loader.
 * The load_addr is part of AOUT kludge setup in dboot_grub.s, to support
 * 32-bit dboot code setup used to set up and start 64-bit kernel.
 * AOUT kludge does allow 32-bit boot loader, such as grub1, to load and
 * start 64-bit illumos kernel.
 */
static void
dboot_loader_init(void)
{
        mb_info = NULL;
        mb2_info = NULL;

        switch (mb_magic) {
        case MB_BOOTLOADER_MAGIC:
                multiboot_version = 1;
                mb_info = (multiboot_info_t *)(uintptr_t)mb_addr;
#if defined(_BOOT_TARGET_amd64)
                load_addr = mb_header.load_addr;
#endif
                break;

        case MULTIBOOT2_BOOTLOADER_MAGIC:
                multiboot_version = 2;
                mb2_info = (multiboot2_info_header_t *)(uintptr_t)mb_addr;
                mb2_mmap_tagp = dboot_multiboot2_get_mmap_tagp(mb2_info);
#if defined(_BOOT_TARGET_amd64)
                load_addr = mb2_load_addr;
#endif
                break;

        default:
                dboot_panic("Unknown bootloader magic: 0x%x\n", mb_magic);
                break;
        }
}

/* Extract the kernel command line from [multi]boot information. */
static char *
dboot_loader_cmdline(void)
{
        char *line = NULL;


        switch (multiboot_version) {
        case 1:
                if (mb_info->flags & MB_INFO_CMDLINE)
                        line = (char *)mb_info->cmdline;
                break;

        case 2:
                line = dboot_multiboot2_cmdline(mb2_info);
                break;

        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }


        /*
         * Make sure we have valid pointer so the string operations
         * will not crash us.
         */
        if (line == NULL)
                line = "";

        return (line);
}

static char *
dboot_loader_name(void)
{
        multiboot_tag_string_t *tag;

        switch (multiboot_version) {
        case 1:
                return ((char *)mb_info->boot_loader_name);

        case 2:
                tag = dboot_multiboot2_find_tag(mb2_info,
                    MULTIBOOT_TAG_TYPE_BOOT_LOADER_NAME);
                return (tag->mb_string);
        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }

        return (NULL);
}

/*
 * startup_kernel has a pretty simple job. It builds pagetables which reflect
 * 1:1 mappings for all memory in use. It then also adds mappings for
 * the kernel nucleus at virtual address of target_kernel_text using large page
 * mappings. The page table pages are also accessible at 1:1 mapped
 * virtual addresses.
 */
/*ARGSUSED*/
void
startup_kernel(void)
{
        char *cmdline;
        char *bootloader;

        dboot_loader_init();
        /*
         * At this point we are executing in a 32 bit real mode.
         */

        bootloader = dboot_loader_name();
        cmdline = dboot_loader_cmdline();


        dboot_init_xboot_consinfo();
        bi->bi_cmdline = (native_ptr_t)(uintptr_t)cmdline;
        bcons_init(bi);

        prom_debug = (find_boot_prop("prom_debug") != NULL);
        map_debug = (find_boot_prop("map_debug") != NULL);

        dboot_multiboot_get_fwtables();
        DBG_MSG("\n\nillumos prekernel set: ");
        DBG_MSG(cmdline);
        DBG_MSG("\n");

        if (bootloader != NULL && prom_debug) {
                dboot_printf("Kernel loaded by: %s\n", bootloader);
                dboot_printf("Using multiboot %d boot protocol.\n",
                    multiboot_version);
        }

        DBG((uintptr_t)bi);
        DBG((uintptr_t)mb_info);
        DBG((uintptr_t)mb2_info);
        if (mb2_info != NULL)
                DBG(mb2_info->mbi_total_size);
        DBG(bi->bi_acpi_rsdp);
        DBG(bi->bi_smbios);

        /*
         * Need correct target_kernel_text value
         */
#if defined(_BOOT_TARGET_amd64)
        target_kernel_text = KERNEL_TEXT_amd64;
#elif defined(__xpv)
        target_kernel_text = KERNEL_TEXT_i386_xpv;
#else
        target_kernel_text = KERNEL_TEXT_i386;
#endif
        DBG(target_kernel_text);


        /*
         * use cpuid to enable MMU features
         */
        if (have_cpuid()) {
                uint32_t eax, edx;

                eax = 1;
                edx = get_cpuid_edx(&eax);
                if (edx & CPUID_INTC_EDX_PSE)
                        largepage_support = 1;
                if (edx & CPUID_INTC_EDX_PGE)
                        pge_support = 1;
                if (edx & CPUID_INTC_EDX_PAE)
                        pae_support = 1;

                eax = 0x80000000;
                edx = get_cpuid_edx(&eax);
                if (eax >= 0x80000001) {
                        eax = 0x80000001;
                        edx = get_cpuid_edx(&eax);
                        if (edx & CPUID_AMD_EDX_LM)
                                amd64_support = 1;
                        if (edx & CPUID_AMD_EDX_NX)
                                NX_support = 1;
                }
        } else {
                dboot_printf("cpuid not supported\n");
        }


#if defined(_BOOT_TARGET_amd64)
        if (amd64_support == 0)
                dboot_panic("long mode not supported, rebooting");
        else if (pae_support == 0)
                dboot_panic("long mode, but no PAE; rebooting");
#else
        /*
         * Allow the command line to over-ride use of PAE for 32 bit.
         */
        if (strstr(cmdline, "disablePAE=true") != NULL) {
                pae_support = 0;
                NX_support = 0;
                amd64_support = 0;
        }
#endif

        /*
         * initialize the simple memory allocator
         */
        init_mem_alloc();

#if !defined(__xpv) && !defined(_BOOT_TARGET_amd64)
        /*
         * disable PAE on 32 bit h/w w/o NX and < 4Gig of memory
         */
        if (max_mem < FOUR_GIG && NX_support == 0)
                pae_support = 0;
#endif

        /*
         * configure mmu information
         */
        if (pae_support) {
                shift_amt = shift_amt_pae;
                ptes_per_table = 512;
                pte_size = 8;
                lpagesize = TWO_MEG;
#if defined(_BOOT_TARGET_amd64)
                top_level = 3;
#else
                top_level = 2;
#endif
        } else {
                pae_support = 0;
                NX_support = 0;
                shift_amt = shift_amt_nopae;
                ptes_per_table = 1024;
                pte_size = 4;
                lpagesize = FOUR_MEG;
                top_level = 1;
        }

        DBG(pge_support);
        DBG(NX_support);
        DBG(largepage_support);
        DBG(amd64_support);
        DBG(top_level);
        DBG(pte_size);
        DBG(ptes_per_table);
        DBG(lpagesize);

        ktext_phys = FOUR_MEG;          /* from UNIX Mapfile */

#if !defined(__xpv) && defined(_BOOT_TARGET_amd64)
        /*
         * For grub, copy kernel bits from the ELF64 file to final place.
         */
        DBG_MSG("\nAllocating nucleus pages.\n");
        ktext_phys = (uintptr_t)do_mem_alloc(ksize, FOUR_MEG);
        if (ktext_phys == 0)
                dboot_panic("failed to allocate aligned kernel memory");
        DBG(load_addr);
        if (dboot_elfload64(load_addr) != 0)
                dboot_panic("failed to parse kernel ELF image, rebooting");
#endif

        DBG(ktext_phys);

        /*
         * Allocate page tables.
         */
        build_page_tables();

        /*
         * return to assembly code to switch to running kernel
         */
        entry_addr_low = (uint32_t)target_kernel_text;
        DBG(entry_addr_low);
        bi->bi_use_largepage = largepage_support;
        bi->bi_use_pae = pae_support;
        bi->bi_use_pge = pge_support;
        bi->bi_use_nx = NX_support;


        bi->bi_next_paddr = next_avail_addr;
        DBG(bi->bi_next_paddr);
        bi->bi_next_vaddr = (uintptr_t)next_avail_addr;
        DBG(bi->bi_next_vaddr);
        bi->bi_mb_version = multiboot_version;

        switch (multiboot_version) {
        case 1:
                bi->bi_mb_info = (uintptr_t)mb_info;
                break;
        case 2:
                bi->bi_mb_info = (uintptr_t)mb2_info;
                break;
        default:
                dboot_panic("Unknown multiboot version: %d\n",
                    multiboot_version);
                break;
        }
        bi->bi_top_page_table = (uintptr_t)top_page_table;


        bi->bi_kseg_size = FOUR_MEG;
        DBG(bi->bi_kseg_size);

        if (map_debug)
                dump_tables();

        DBG_MSG("\n\n*** DBOOT DONE -- back to asm to jump to kernel\n\n");
}