Esempio n. 1
0
/*
 * 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;
#if defined(__xpv)
		start += mfn_base;
#endif
		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;
#if defined(__xpv)
	if (next_avail_addr > scratch_end)
		dboot_panic("Out of mem next_avail: 0x%lx, scratch_end: "
		    "0x%lx", (ulong_t)next_avail_addr,
		    (ulong_t)scratch_end);
#endif
	(void) memset((void *)(uintptr_t)best, 0, size);
	return ((void *)(uintptr_t)best);
}
Esempio n. 2
0
/*
 * 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);

#if defined(__xpv)
	/*
	 * see if we can avoid find_pte() on the hypervisor
	 */
	if (HYPERVISOR_update_va_mapping(va, pteval,
	    UVMF_INVLPG | UVMF_LOCAL) == 0)
		return;
#endif

	/*
	 * 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 defined(__xpv)
	ptep = ptep;	/* shut lint up */
	if (HYPERVISOR_update_va_mapping(va, pteval, UVMF_INVLPG | UVMF_LOCAL))
		dboot_panic("mmu_update failed-map_pa_at_va va=0x%" PRIx64
		    " l=%d ma=0x%" PRIx64 ", pte=0x%" PRIx64 "",
		    (uint64_t)va, level, (uint64_t)ma, pteval);
#else
	if (va < 1024 * 1024)
		pteval |= PT_NOCACHE;		/* for video RAM */
	if (pae_support)
		*ptep = pteval;
	else
		*((x86pte32_t *)ptep) = (x86pte32_t)pteval;
#endif
}
Esempio n. 3
0
static void *
getehdr(void)
{
	uchar_t *ident;
	void *hdr = NULL;

	ident = PGETBYTES(0);
	if (ident == NULL)
		dboot_panic("Cannot read kernel ELF header");

	if (ident[EI_MAG0] != ELFMAG0 || ident[EI_MAG1] != ELFMAG1 ||
	    ident[EI_MAG2] != ELFMAG2 || ident[EI_MAG3] != ELFMAG3)
		dboot_panic("not an ELF file!");

	if (ident[EI_CLASS] == ELFCLASS32)
		hdr = PGETBYTES(0);
	else if (ident[EI_CLASS] == ELFCLASS64)
		hdr = PGETBYTES(0);
	else
		dboot_panic("Unknown ELF class");

	return (hdr);
}
Esempio n. 4
0
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;
		}
	}
}
Esempio n. 5
0
/*
 * From a pseudo-physical address, find the corresponding machine address.
 */
maddr_t
pa_to_ma(paddr_t pa)
{
	pfn_t pfn;
	ulong_t mfn;

	pfn = mmu_btop(pa - mfn_base);
	if (pa < mfn_base || pfn >= xen_info->nr_pages)
		dboot_panic("pa_to_ma(): illegal address 0x%lx", (ulong_t)pa);
	mfn = ((ulong_t *)xen_info->mfn_list)[pfn];
#ifdef DEBUG
	if (mfn_to_pfn_mapping[mfn] != pfn)
		dboot_printf("pa_to_ma(pfn=%lx) got %lx ma_to_pa() says %lx\n",
		    pfn, mfn, mfn_to_pfn_mapping[mfn]);
#endif
	return (mfn_to_ma(mfn) | (pa & MMU_PAGEOFFSET));
}
Esempio n. 6
0
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;

#ifdef __xpv
	/* Remove write permission to the new page table. */
	if (HYPERVISOR_update_va_mapping(new_table,
	    *pteval & ~(x86pte_t)PT_WRITABLE, UVMF_INVLPG | UVMF_LOCAL))
		dboot_panic("HYP_update_va_mapping error");
#endif

	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);
}
Esempio n. 7
0
/*ARGSUSED*/
void
set_pteval(paddr_t table, uint_t index, uint_t level, x86pte_t pteval)
{
#ifdef __xpv
	mmu_update_t t;
	maddr_t mtable = pa_to_ma(table);
	int retcnt;

	t.ptr = (mtable + index * pte_size) | MMU_NORMAL_PT_UPDATE;
	t.val = pteval;
	if (HYPERVISOR_mmu_update(&t, 1, &retcnt, DOMID_SELF) || retcnt != 1)
		dboot_panic("HYPERVISOR_mmu_update() failed");
#else /* __xpv */
	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();
#endif /* __xpv */
}
Esempio n. 8
0
/*
 * parse the elf file for program information
 */
int
dboot_elfload64(uintptr_t file_image)
{
	Elf64_Ehdr *eh;
	Elf64_Phdr *phdr;
	Elf64_Shdr *shdr;
	caddr_t allphdrs, sechdrs;
	int i;
	paddr_t src;
	paddr_t dst;
	paddr_t next_addr;

	elf_file = (caddr_t)file_image;

	allphdrs = NULL;

	eh = getehdr();
	if (eh == NULL)
		dboot_panic("getehdr() failed");

	if (eh->e_type != ET_EXEC)
		dboot_panic("not ET_EXEC, e_type = 0x%x", eh->e_type);

	if (eh->e_phnum == 0 || eh->e_phoff == 0)
		dboot_panic("no program headers");

	/*
	 * Get the program headers.
	 */
	allphdrs = PGETBYTES(eh->e_phoff);
	if (allphdrs == NULL)
		dboot_panic("Failed to get program headers e_phnum = %d",
		    eh->e_phnum);

	/*
	 * Get the section headers.
	 */
	sechdrs = PGETBYTES(eh->e_shoff);
	if (sechdrs == NULL)
		dboot_panic("Failed to get section headers e_shnum = %d",
		    eh->e_shnum);

	/*
	 * Next look for interesting program headers.
	 */
	for (i = 0; i < eh->e_phnum; i++) {
		/*LINTED [ELF program header alignment]*/
		phdr = (Elf64_Phdr *)(allphdrs + eh->e_phentsize * i);

		/*
		 * Dynamically-linked executable.
		 * Complain.
		 */
		if (phdr->p_type == PT_INTERP) {
			dboot_printf("warning: PT_INTERP section\n");
			continue;
		}

		/*
		 * at this point we only care about PT_LOAD segments
		 */
		if (phdr->p_type != PT_LOAD)
			continue;

		if (phdr->p_flags == (PF_R | PF_W) && phdr->p_vaddr == 0) {
			dboot_printf("warning: krtld reloc info?\n");
			continue;
		}

		/*
		 * If memory size is zero just ignore this header.
		 */
		if (phdr->p_memsz == 0)
			continue;

		/*
		 * If load address 1:1 then ignore this header.
		 */
		if (phdr->p_paddr == phdr->p_vaddr) {
			if (prom_debug)
				dboot_printf("Skipping PT_LOAD segment for "
				    "paddr = 0x%lx\n", (ulong_t)phdr->p_paddr);
			continue;
		}

		/*
		 * copy the data to kernel area
		 */
		if (phdr->p_paddr != FOUR_MEG && phdr->p_paddr != 2 * FOUR_MEG)
			dboot_panic("Bad paddr for kernel nucleus segment");
		src = (uintptr_t)PGETBYTES(phdr->p_offset);
		dst = ktext_phys + phdr->p_paddr - FOUR_MEG;
		if (prom_debug)
			dboot_printf("copying %ld bytes from ELF offset 0x%lx "
			    "to physaddr 0x%lx (va=0x%lx)\n",
			    (ulong_t)phdr->p_filesz, (ulong_t)phdr->p_offset,
			    (ulong_t)dst, (ulong_t)phdr->p_vaddr);
		(void) memcpy((void *)(uintptr_t)dst,
		    (void *)(uintptr_t)src, (size_t)phdr->p_filesz);

		next_addr = dst + phdr->p_filesz;
	}


	/*
	 * Next look for bss
	 */
	for (i = 0; i < eh->e_shnum; i++) {
		shdr = (Elf64_Shdr *)(sechdrs + eh->e_shentsize * i);

		/* zero out bss */
		if (shdr->sh_type == SHT_NOBITS) {
			if (prom_debug)
				dboot_printf("zeroing BSS %ld bytes from "
				    "physaddr 0x%llx (end=0x%llx)\n",
				    (ulong_t)shdr->sh_size,
				    (long long unsigned)next_addr,
				    next_addr + shdr->sh_size);
			(void) memset((void *)(uintptr_t)next_addr, 0,
			    shdr->sh_size);
			break;
		}
	}

	/*
	 * Ignore the intepreter (or should we die if there is one??)
	 */
	return (0);
}
Esempio n. 9
0
/*
 * Walk through the module information finding the last used address.
 * The first available address will become the top level page table.
 *
 * We then build the phys_install memlist from the multiboot information.
 */
static void
init_mem_alloc(void)
{
	mb_memory_map_t *mmap;
	mb_module_t *mod;
	uint64_t start;
	uint64_t end;
	uint64_t page_offset = MMU_PAGEOFFSET;	/* needs to be 64 bits */
	extern char _end[];
	int i;

	DBG_MSG("Entered init_mem_alloc()\n");
	DBG((uintptr_t)mb_info);

	if (mb_info->mods_count > MAX_MODULES) {
		dboot_panic("Too many modules (%d) -- the maximum is %d.",
		    mb_info->mods_count, MAX_MODULES);
	}
	/*
	 * search the modules to find the last used address
	 * we'll build the module list while we're walking through here
	 */
	DBG_MSG("\nFinding Modules\n");
	check_higher((paddr_t)&_end);
	for (mod = (mb_module_t *)(mb_info->mods_addr), i = 0;
	    i < mb_info->mods_count;
	    ++mod, ++i) {
		if (prom_debug) {
			dboot_printf("\tmodule #%d: %s at: 0x%lx, len 0x%lx\n",
			    i, (char *)(mod->mod_name),
			    (ulong_t)mod->mod_start, (ulong_t)mod->mod_end);
		}
		modules[i].bm_addr = mod->mod_start;
		if (mod->mod_start > mod->mod_end) {
			dboot_panic("module[%d]: Invalid module start address "
			    "(0x%llx)", i, (uint64_t)mod->mod_start);
		}
		modules[i].bm_size = mod->mod_end - mod->mod_start;

		check_higher(mod->mod_end);
	}
	bi->bi_modules = (native_ptr_t)modules;
	DBG(bi->bi_modules);
	bi->bi_module_cnt = mb_info->mods_count;
	DBG(bi->bi_module_cnt);

	/*
	 * 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");
	DBG(mb_info->flags);
	max_mem = 0;
	if (mb_info->flags & 0x40) {
		int cnt = 0;

		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))) {
			++cnt;
			start = ((uint64_t)mmap->base_addr_high << 32) +
			    mmap->base_addr_low;
			end = start + ((uint64_t)mmap->length_high << 32) +
			    mmap->length_low;

			if (prom_debug)
				dboot_printf("\ttype: %d %" PRIx64 "..%"
				    PRIx64 "\n", mmap->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 (mmap->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((mb_memory_map_t *)mb_info->mmap_addr, cnt);
	} else if (mb_info->flags & 0x01) {
		DBG(mb_info->mem_lower);
		memlists[memlists_used].addr = 0;
		memlists[memlists_used].size = mb_info->mem_lower * 1024;
		++memlists_used;
		DBG(mb_info->mem_upper);
		memlists[memlists_used].addr = 1024 * 1024;
		memlists[memlists_used].size = mb_info->mem_upper * 1024;
		++memlists_used;

		/*
		 * Old platform - assume I/O space at the end of memory.
		 */
		pcimemlists[0].addr =
		    (mb_info->mem_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)pcimemlists;
		DBG(bi->bi_pcimem);
	} else {
		dboot_panic("No memory info from boot loader!!!");
	}

	check_higher(bi->bi_cmdline);

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

	/*
	 * build bios reserved mem lists
	 */
	build_rsvdmemlists();
}
Esempio n. 10
0
static void
init_mem_alloc(void)
{
	int	local;	/* variables needed to find start region */
	paddr_t	scratch_start;
	xen_memory_map_t map;

	DBG_MSG("Entered init_mem_alloc()\n");

	/*
	 * Free memory follows the stack. There's at least 512KB of scratch
	 * space, rounded up to at least 2Mb alignment.  That should be enough
	 * for the page tables we'll need to build.  The nucleus memory is
	 * allocated last and will be outside the addressible range.  We'll
	 * switch to new page tables before we unpack the kernel
	 */
	scratch_start = RNDUP((paddr_t)(uintptr_t)&local, MMU_PAGESIZE);
	DBG(scratch_start);
	scratch_end = RNDUP((paddr_t)scratch_start + 512 * 1024, TWO_MEG);
	DBG(scratch_end);

	/*
	 * For paranoia, leave some space between hypervisor data and ours.
	 * Use 500 instead of 512.
	 */
	next_avail_addr = scratch_end - 500 * 1024;
	DBG(next_avail_addr);

	/*
	 * The domain builder gives us at most 1 module
	 */
	DBG(xen_info->mod_len);
	if (xen_info->mod_len > 0) {
		DBG(xen_info->mod_start);
		modules[0].bm_addr = xen_info->mod_start;
		modules[0].bm_size = xen_info->mod_len;
		bi->bi_module_cnt = 1;
		bi->bi_modules = (native_ptr_t)modules;
	} else {
		bi->bi_module_cnt = 0;
		bi->bi_modules = NULL;
	}
	DBG(bi->bi_module_cnt);
	DBG(bi->bi_modules);

	DBG(xen_info->mfn_list);
	DBG(xen_info->nr_pages);
	max_mem = (paddr_t)xen_info->nr_pages << MMU_PAGESHIFT;
	DBG(max_mem);

	/*
	 * Using pseudo-physical addresses, so only 1 memlist element
	 */
	memlists[0].addr = 0;
	DBG(memlists[0].addr);
	memlists[0].size = max_mem;
	DBG(memlists[0].size);
	memlists_used = 1;
	DBG(memlists_used);

	/*
	 * finish building physinstall list
	 */
	sort_physinstall();

	/*
	 * build bios reserved memlists
	 */
	build_rsvdmemlists();

	if (DOMAIN_IS_INITDOMAIN(xen_info)) {
		/*
		 * build PCI Memory list
		 */
		map.nr_entries = MAXMAPS;
		/*LINTED: constant in conditional context*/
		set_xen_guest_handle(map.buffer, map_buffer);
		if (HYPERVISOR_memory_op(XENMEM_machine_memory_map, &map) != 0)
			dboot_panic("getting XENMEM_machine_memory_map failed");
		build_pcimemlists(map_buffer, map.nr_entries);
	}
}
Esempio n. 11
0
/*ARGSUSED*/
void
startup_kernel(void)
{
	char *cmdline;
	uintptr_t addr;
#if defined(__xpv)
	physdev_set_iopl_t set_iopl;
#endif /* __xpv */

	/*
	 * At this point we are executing in a 32 bit real mode.
	 */
#if defined(__xpv)
	cmdline = (char *)xen_info->cmd_line;
#else /* __xpv */
	cmdline = (char *)mb_info->cmdline;
#endif /* __xpv */

	prom_debug = (strstr(cmdline, "prom_debug") != NULL);
	map_debug = (strstr(cmdline, "map_debug") != NULL);

#if defined(__xpv)
	/*
	 * For dom0, before we initialize the console subsystem we'll
	 * need to enable io operations, so set I/O priveldge level to 1.
	 */
	if (DOMAIN_IS_INITDOMAIN(xen_info)) {
		set_iopl.iopl = 1;
		(void) HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
	}
#endif /* __xpv */

	bcons_init(cmdline);
	DBG_MSG("\n\nSolaris prekernel set: ");
	DBG_MSG(cmdline);
	DBG_MSG("\n");

	if (strstr(cmdline, "multiboot") != NULL) {
		dboot_panic(NO_MULTIBOOT);
	}

	/*
	 * 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;
	DBG((uintptr_t)bi);
	bi->bi_cmdline = (native_ptr_t)(uintptr_t)cmdline;

	/*
	 * 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);

#if defined(__xpv)

	/*
	 * XXPV	Derive this stuff from CPUID / what the hypervisor has enabled
	 */

#if defined(_BOOT_TARGET_amd64)
	/*
	 * 64-bit hypervisor.
	 */
	amd64_support = 1;
	pae_support = 1;

#else	/* _BOOT_TARGET_amd64 */

	/*
	 * See if we are running on a PAE Hypervisor
	 */
	{
		xen_capabilities_info_t caps;

		if (HYPERVISOR_xen_version(XENVER_capabilities, &caps) != 0)
			dboot_panic("HYPERVISOR_xen_version(caps) failed");
		caps[sizeof (caps) - 1] = 0;
		if (prom_debug)
			dboot_printf("xen capabilities %s\n", caps);
		if (strstr(caps, "x86_32p") != NULL)
			pae_support = 1;
	}

#endif	/* _BOOT_TARGET_amd64 */
	{
		xen_platform_parameters_t p;

		if (HYPERVISOR_xen_version(XENVER_platform_parameters, &p) != 0)
			dboot_panic("HYPERVISOR_xen_version(parms) failed");
		DBG(p.virt_start);
		mfn_to_pfn_mapping = (pfn_t *)(xen_virt_start = p.virt_start);
	}

	/*
	 * The hypervisor loads stuff starting at 1Gig
	 */
	mfn_base = ONE_GIG;
	DBG(mfn_base);

	/*
	 * enable writable page table mode for the hypervisor
	 */
	if (HYPERVISOR_vm_assist(VMASST_CMD_enable,
	    VMASST_TYPE_writable_pagetables) < 0)
		dboot_panic("HYPERVISOR_vm_assist(writable_pagetables) failed");

	/*
	 * check for NX support
	 */
	if (pae_support) {
		uint32_t eax = 0x80000000;
		uint32_t edx = get_cpuid_edx(&eax);

		if (eax >= 0x80000001) {
			eax = 0x80000001;
			edx = get_cpuid_edx(&eax);
			if (edx & CPUID_AMD_EDX_NX)
				NX_support = 1;
		}
	}

#if !defined(_BOOT_TARGET_amd64)

	/*
	 * The 32-bit hypervisor uses segmentation to protect itself from
	 * guests. This means when a guest attempts to install a flat 4GB
	 * code or data descriptor the 32-bit hypervisor will protect itself
	 * by silently shrinking the segment such that if the guest attempts
	 * any access where the hypervisor lives a #gp fault is generated.
	 * The problem is that some applications expect a full 4GB flat
	 * segment for their current thread pointer and will use negative
	 * offset segment wrap around to access data. TLS support in linux
	 * brand is one example of this.
	 *
	 * The 32-bit hypervisor can catch the #gp fault in these cases
	 * and emulate the access without passing the #gp fault to the guest
	 * but only if VMASST_TYPE_4gb_segments is explicitly turned on.
	 * Seems like this should have been the default.
	 * Either way, we want the hypervisor -- and not Solaris -- to deal
	 * to deal with emulating these accesses.
	 */
	if (HYPERVISOR_vm_assist(VMASST_CMD_enable,
	    VMASST_TYPE_4gb_segments) < 0)
		dboot_panic("HYPERVISOR_vm_assist(4gb_segments) failed");
#endif	/* !_BOOT_TARGET_amd64 */

#else	/* __xpv */

	/*
	 * 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");
	}
#endif /* __xpv */


#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);

#if defined(__xpv)
	ktext_phys = ONE_GIG;		/* from UNIX Mapfile */
#else
	ktext_phys = FOUR_MEG;		/* from UNIX Mapfile */
#endif

#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");
	if (dboot_elfload64(mb_header.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;

#if defined(__xpv)

	bi->bi_next_paddr = next_avail_addr - mfn_base;
	DBG(bi->bi_next_paddr);
	bi->bi_next_vaddr = (native_ptr_t)next_avail_addr;
	DBG(bi->bi_next_vaddr);

	/*
	 * unmap unused pages in start area to make them available for DMA
	 */
	while (next_avail_addr < scratch_end) {
		(void) HYPERVISOR_update_va_mapping(next_avail_addr,
		    0, UVMF_INVLPG | UVMF_LOCAL);
		next_avail_addr += MMU_PAGESIZE;
	}

	bi->bi_xen_start_info = (uintptr_t)xen_info;
	DBG((uintptr_t)HYPERVISOR_shared_info);
	bi->bi_shared_info = (native_ptr_t)HYPERVISOR_shared_info;
	bi->bi_top_page_table = (uintptr_t)top_page_table - mfn_base;

#else /* __xpv */

	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_info = (uintptr_t)mb_info;
	bi->bi_top_page_table = (uintptr_t)top_page_table;

#endif /* __xpv */

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

#ifndef __xpv
	if (map_debug)
		dump_tables();
#endif

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