linux/arch/x86/kernel/setup.c
Yinghai Lu 5092301c72 x86: we only have init_pg_tables_end for 32bit
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 13:10:55 +02:00

810 lines
19 KiB
C

/*
* Copyright (C) 1995 Linus Torvalds
*
* Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
*
* Memory region support
* David Parsons <orc@pell.chi.il.us>, July-August 1999
*
* Added E820 sanitization routine (removes overlapping memory regions);
* Brian Moyle <bmoyle@mvista.com>, February 2001
*
* Moved CPU detection code to cpu/${cpu}.c
* Patrick Mochel <mochel@osdl.org>, March 2002
*
* Provisions for empty E820 memory regions (reported by certain BIOSes).
* Alex Achenbach <xela@slit.de>, December 2002.
*
*/
/*
* This file handles the architecture-dependent parts of initialization
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/screen_info.h>
#include <linux/ioport.h>
#include <linux/acpi.h>
#include <linux/apm_bios.h>
#include <linux/initrd.h>
#include <linux/bootmem.h>
#include <linux/seq_file.h>
#include <linux/console.h>
#include <linux/mca.h>
#include <linux/root_dev.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <linux/efi.h>
#include <linux/init.h>
#include <linux/edd.h>
#include <linux/iscsi_ibft.h>
#include <linux/nodemask.h>
#include <linux/kexec.h>
#include <linux/dmi.h>
#include <linux/pfn.h>
#include <linux/pci.h>
#include <asm/pci-direct.h>
#include <linux/init_ohci1394_dma.h>
#include <linux/kvm_para.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/delay.h>
#include <linux/highmem.h>
#include <linux/kallsyms.h>
#include <linux/edd.h>
#include <linux/iscsi_ibft.h>
#include <linux/kexec.h>
#include <linux/cpufreq.h>
#include <linux/dma-mapping.h>
#include <linux/ctype.h>
#include <linux/uaccess.h>
#include <linux/percpu.h>
#include <linux/crash_dump.h>
#include <video/edid.h>
#include <asm/mtrr.h>
#include <asm/apic.h>
#include <asm/e820.h>
#include <asm/mpspec.h>
#include <asm/setup.h>
#include <asm/arch_hooks.h>
#include <asm/efi.h>
#include <asm/sections.h>
#include <asm/dmi.h>
#include <asm/io_apic.h>
#include <asm/ist.h>
#include <asm/vmi.h>
#include <setup_arch.h>
#include <asm/bios_ebda.h>
#include <asm/cacheflush.h>
#include <asm/processor.h>
#include <asm/bugs.h>
#include <asm/system.h>
#include <asm/vsyscall.h>
#include <asm/smp.h>
#include <asm/desc.h>
#include <asm/dma.h>
#include <asm/gart.h>
#include <asm/mmu_context.h>
#include <asm/proto.h>
#include <mach_apic.h>
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define ARCH_SETUP
#endif
#include <asm/percpu.h>
#include <asm/sections.h>
#include <asm/topology.h>
#include <asm/apicdef.h>
#ifdef CONFIG_X86_64
#include <asm/numa_64.h>
#endif
#ifdef CONFIG_X86_32
#include <asm/highmem.h>
#endif
#ifndef CONFIG_DEBUG_BOOT_PARAMS
struct boot_params __initdata boot_params;
#else
struct boot_params boot_params;
#endif
/*
* Machine setup..
*/
static struct resource data_resource = {
.name = "Kernel data",
.start = 0,
.end = 0,
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
static struct resource code_resource = {
.name = "Kernel code",
.start = 0,
.end = 0,
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
static struct resource bss_resource = {
.name = "Kernel bss",
.start = 0,
.end = 0,
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
#ifdef CONFIG_X86_32
/* This value is set up by the early boot code to point to the value
immediately after the boot time page tables. It contains a *physical*
address, and must not be in the .bss segment! */
unsigned long init_pg_tables_start __initdata = ~0UL;
unsigned long init_pg_tables_end __initdata = ~0UL;
static struct resource video_ram_resource = {
.name = "Video RAM area",
.start = 0xa0000,
.end = 0xbffff,
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
/* cpu data as detected by the assembly code in head.S */
struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
/* common cpu data for all cpus */
struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
EXPORT_SYMBOL(boot_cpu_data);
static void set_mca_bus(int x)
{
#ifdef CONFIG_MCA
MCA_bus = x;
#endif
}
unsigned int def_to_bigsmp;
/* for MCA, but anyone else can use it if they want */
unsigned int machine_id;
unsigned int machine_submodel_id;
unsigned int BIOS_revision;
struct apm_info apm_info;
EXPORT_SYMBOL(apm_info);
#if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
struct ist_info ist_info;
EXPORT_SYMBOL(ist_info);
#else
struct ist_info ist_info;
#endif
#else
struct cpuinfo_x86 boot_cpu_data __read_mostly;
EXPORT_SYMBOL(boot_cpu_data);
#endif
#if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
unsigned long mmu_cr4_features;
#else
unsigned long mmu_cr4_features = X86_CR4_PAE;
#endif
/* Boot loader ID as an integer, for the benefit of proc_dointvec */
int bootloader_type;
/*
* Early DMI memory
*/
int dmi_alloc_index;
char dmi_alloc_data[DMI_MAX_DATA];
/*
* Setup options
*/
struct screen_info screen_info;
EXPORT_SYMBOL(screen_info);
struct edid_info edid_info;
EXPORT_SYMBOL_GPL(edid_info);
extern int root_mountflags;
unsigned long saved_video_mode;
#define RAMDISK_IMAGE_START_MASK 0x07FF
#define RAMDISK_PROMPT_FLAG 0x8000
#define RAMDISK_LOAD_FLAG 0x4000
static char __initdata command_line[COMMAND_LINE_SIZE];
#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
struct edd edd;
#ifdef CONFIG_EDD_MODULE
EXPORT_SYMBOL(edd);
#endif
/**
* copy_edd() - Copy the BIOS EDD information
* from boot_params into a safe place.
*
*/
static inline void copy_edd(void)
{
memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
sizeof(edd.mbr_signature));
memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
edd.edd_info_nr = boot_params.eddbuf_entries;
}
#else
static inline void copy_edd(void)
{
}
#endif
#ifdef CONFIG_BLK_DEV_INITRD
#ifdef CONFIG_X86_32
#define MAX_MAP_CHUNK (NR_FIX_BTMAPS << PAGE_SHIFT)
static void __init relocate_initrd(void)
{
u64 ramdisk_image = boot_params.hdr.ramdisk_image;
u64 ramdisk_size = boot_params.hdr.ramdisk_size;
u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
u64 ramdisk_here;
unsigned long slop, clen, mapaddr;
char *p, *q;
/* We need to move the initrd down into lowmem */
ramdisk_here = find_e820_area(0, end_of_lowmem, ramdisk_size,
PAGE_SIZE);
if (ramdisk_here == -1ULL)
panic("Cannot find place for new RAMDISK of size %lld\n",
ramdisk_size);
/* Note: this includes all the lowmem currently occupied by
the initrd, we rely on that fact to keep the data intact. */
reserve_early(ramdisk_here, ramdisk_here + ramdisk_size,
"NEW RAMDISK");
initrd_start = ramdisk_here + PAGE_OFFSET;
initrd_end = initrd_start + ramdisk_size;
printk(KERN_INFO "Allocated new RAMDISK: %08llx - %08llx\n",
ramdisk_here, ramdisk_here + ramdisk_size);
q = (char *)initrd_start;
/* Copy any lowmem portion of the initrd */
if (ramdisk_image < end_of_lowmem) {
clen = end_of_lowmem - ramdisk_image;
p = (char *)__va(ramdisk_image);
memcpy(q, p, clen);
q += clen;
ramdisk_image += clen;
ramdisk_size -= clen;
}
/* Copy the highmem portion of the initrd */
while (ramdisk_size) {
slop = ramdisk_image & ~PAGE_MASK;
clen = ramdisk_size;
if (clen > MAX_MAP_CHUNK-slop)
clen = MAX_MAP_CHUNK-slop;
mapaddr = ramdisk_image & PAGE_MASK;
p = early_ioremap(mapaddr, clen+slop);
memcpy(q, p+slop, clen);
early_iounmap(p, clen+slop);
q += clen;
ramdisk_image += clen;
ramdisk_size -= clen;
}
/* high pages is not converted by early_res_to_bootmem */
ramdisk_image = boot_params.hdr.ramdisk_image;
ramdisk_size = boot_params.hdr.ramdisk_size;
printk(KERN_INFO "Move RAMDISK from %016llx - %016llx to"
" %08llx - %08llx\n",
ramdisk_image, ramdisk_image + ramdisk_size - 1,
ramdisk_here, ramdisk_here + ramdisk_size - 1);
}
#endif
static void __init reserve_initrd(void)
{
u64 ramdisk_image = boot_params.hdr.ramdisk_image;
u64 ramdisk_size = boot_params.hdr.ramdisk_size;
u64 ramdisk_end = ramdisk_image + ramdisk_size;
u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
if (!boot_params.hdr.type_of_loader ||
!ramdisk_image || !ramdisk_size)
return; /* No initrd provided by bootloader */
initrd_start = 0;
if (ramdisk_size >= (end_of_lowmem>>1)) {
free_early(ramdisk_image, ramdisk_end);
printk(KERN_ERR "initrd too large to handle, "
"disabling initrd\n");
return;
}
printk(KERN_INFO "RAMDISK: %08llx - %08llx\n", ramdisk_image,
ramdisk_end);
if (ramdisk_end <= end_of_lowmem) {
/* All in lowmem, easy case */
/*
* don't need to reserve again, already reserved early
* in i386_start_kernel
*/
initrd_start = ramdisk_image + PAGE_OFFSET;
initrd_end = initrd_start + ramdisk_size;
return;
}
#ifdef CONFIG_X86_32
relocate_initrd();
#else
printk(KERN_ERR "initrd extends beyond end of memory "
"(0x%08llx > 0x%08llx)\ndisabling initrd\n",
ramdisk_end, end_of_lowmem);
initrd_start = 0;
#endif
free_early(ramdisk_image, ramdisk_end);
}
#else
static void __init reserve_initrd(void)
{
}
#endif /* CONFIG_BLK_DEV_INITRD */
static void __init parse_setup_data(void)
{
struct setup_data *data;
u64 pa_data;
if (boot_params.hdr.version < 0x0209)
return;
pa_data = boot_params.hdr.setup_data;
while (pa_data) {
data = early_ioremap(pa_data, PAGE_SIZE);
switch (data->type) {
case SETUP_E820_EXT:
parse_e820_ext(data, pa_data);
break;
default:
break;
}
#ifndef CONFIG_DEBUG_BOOT_PARAMS
free_early(pa_data, pa_data+sizeof(*data)+data->len);
#endif
pa_data = data->next;
early_iounmap(data, PAGE_SIZE);
}
}
/*
* --------- Crashkernel reservation ------------------------------
*/
#ifdef CONFIG_KEXEC
static inline unsigned long long get_total_mem(void)
{
unsigned long long total;
total = max_low_pfn - min_low_pfn;
#ifdef CONFIG_HIGHMEM
total += highend_pfn - highstart_pfn;
#endif
return total << PAGE_SHIFT;
}
static void __init reserve_crashkernel(void)
{
unsigned long long total_mem;
unsigned long long crash_size, crash_base;
int ret;
total_mem = get_total_mem();
ret = parse_crashkernel(boot_command_line, total_mem,
&crash_size, &crash_base);
if (ret == 0 && crash_size > 0) {
if (crash_base <= 0) {
printk(KERN_INFO "crashkernel reservation failed - "
"you have to specify a base address\n");
return;
}
if (reserve_bootmem_generic(crash_base, crash_size,
BOOTMEM_EXCLUSIVE) < 0) {
printk(KERN_INFO "crashkernel reservation failed - "
"memory is in use\n");
return;
}
printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
"for crashkernel (System RAM: %ldMB)\n",
(unsigned long)(crash_size >> 20),
(unsigned long)(crash_base >> 20),
(unsigned long)(total_mem >> 20));
crashk_res.start = crash_base;
crashk_res.end = crash_base + crash_size - 1;
insert_resource(&iomem_resource, &crashk_res);
}
}
#else
static void __init reserve_crashkernel(void)
{
}
#endif
static struct resource standard_io_resources[] = {
{ .name = "dma1", .start = 0x00, .end = 0x1f,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "pic1", .start = 0x20, .end = 0x21,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "timer0", .start = 0x40, .end = 0x43,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "timer1", .start = 0x50, .end = 0x53,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "keyboard", .start = 0x60, .end = 0x60,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "keyboard", .start = 0x64, .end = 0x64,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "pic2", .start = 0xa0, .end = 0xa1,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "dma2", .start = 0xc0, .end = 0xdf,
.flags = IORESOURCE_BUSY | IORESOURCE_IO },
{ .name = "fpu", .start = 0xf0, .end = 0xff,
.flags = IORESOURCE_BUSY | IORESOURCE_IO }
};
static void __init reserve_standard_io_resources(void)
{
int i;
/* request I/O space for devices used on all i[345]86 PCs */
for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
request_resource(&ioport_resource, &standard_io_resources[i]);
}
#ifdef CONFIG_PROC_VMCORE
/* elfcorehdr= specifies the location of elf core header
* stored by the crashed kernel. This option will be passed
* by kexec loader to the capture kernel.
*/
static int __init setup_elfcorehdr(char *arg)
{
char *end;
if (!arg)
return -EINVAL;
elfcorehdr_addr = memparse(arg, &end);
return end > arg ? 0 : -EINVAL;
}
early_param("elfcorehdr", setup_elfcorehdr);
#endif
/*
* Determine if we were loaded by an EFI loader. If so, then we have also been
* passed the efi memmap, systab, etc., so we should use these data structures
* for initialization. Note, the efi init code path is determined by the
* global efi_enabled. This allows the same kernel image to be used on existing
* systems (with a traditional BIOS) as well as on EFI systems.
*/
/*
* setup_arch - architecture-specific boot-time initializations
*
* Note: On x86_64, fixmaps are ready for use even before this is called.
*/
void __init setup_arch(char **cmdline_p)
{
#ifdef CONFIG_X86_32
memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
pre_setup_arch_hook();
early_cpu_init();
early_ioremap_init();
reserve_setup_data();
#else
printk(KERN_INFO "Command line: %s\n", boot_command_line);
#endif
ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
screen_info = boot_params.screen_info;
edid_info = boot_params.edid_info;
#ifdef CONFIG_X86_32
apm_info.bios = boot_params.apm_bios_info;
ist_info = boot_params.ist_info;
if (boot_params.sys_desc_table.length != 0) {
set_mca_bus(boot_params.sys_desc_table.table[3] & 0x2);
machine_id = boot_params.sys_desc_table.table[0];
machine_submodel_id = boot_params.sys_desc_table.table[1];
BIOS_revision = boot_params.sys_desc_table.table[2];
}
#endif
saved_video_mode = boot_params.hdr.vid_mode;
bootloader_type = boot_params.hdr.type_of_loader;
#ifdef CONFIG_BLK_DEV_RAM
rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
#endif
#ifdef CONFIG_EFI
if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
#ifdef CONFIG_X86_32
"EL32",
#else
"EL64",
#endif
4)) {
efi_enabled = 1;
efi_reserve_early();
}
#endif
ARCH_SETUP
setup_memory_map();
copy_edd();
if (!boot_params.hdr.root_flags)
root_mountflags &= ~MS_RDONLY;
init_mm.start_code = (unsigned long) _text;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
#ifdef CONFIG_X86_32
init_mm.brk = init_pg_tables_end + PAGE_OFFSET;
#else
init_mm.brk = (unsigned long) &_end;
#endif
code_resource.start = virt_to_phys(_text);
code_resource.end = virt_to_phys(_etext)-1;
data_resource.start = virt_to_phys(_etext);
data_resource.end = virt_to_phys(_edata)-1;
bss_resource.start = virt_to_phys(&__bss_start);
bss_resource.end = virt_to_phys(&__bss_stop)-1;
#ifdef CONFIG_X86_64
early_cpu_init();
#endif
strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
*cmdline_p = command_line;
parse_setup_data();
parse_early_param();
if (acpi_mps_check()) {
#ifdef CONFIG_X86_LOCAL_APIC
#ifdef CONFIG_X86_32
enable_local_apic = -1;
#else
disable_apic = 1;
#endif
#endif
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
}
finish_e820_parsing();
#ifdef CONFIG_X86_32
probe_roms();
#else
# ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
if (init_ohci1394_dma_early)
init_ohci1394_dma_on_all_controllers();
# endif
#endif
/* after parse_early_param, so could debug it */
insert_resource(&iomem_resource, &code_resource);
insert_resource(&iomem_resource, &data_resource);
insert_resource(&iomem_resource, &bss_resource);
if (efi_enabled)
efi_init();
#ifdef CONFIG_X86_32
if (ppro_with_ram_bug()) {
e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
E820_RESERVED);
sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
printk(KERN_INFO "fixed physical RAM map:\n");
e820_print_map("bad_ppro");
}
#else
early_gart_iommu_check();
#endif
e820_register_active_regions(0, 0, -1UL);
/*
* partially used pages are not usable - thus
* we are rounding upwards:
*/
max_pfn = e820_end_of_ram();
/* preallocate 4k for mptable mpc */
early_reserve_e820_mpc_new();
/* update e820 for memory not covered by WB MTRRs */
mtrr_bp_init();
if (mtrr_trim_uncached_memory(max_pfn)) {
remove_all_active_ranges();
e820_register_active_regions(0, 0, -1UL);
max_pfn = e820_end_of_ram();
}
#ifdef CONFIG_X86_32
/* max_low_pfn get updated here */
find_low_pfn_range();
#else
num_physpages = max_pfn;
check_efer();
/* How many end-of-memory variables you have, grandma! */
/* need this before calling reserve_initrd */
max_low_pfn = max_pfn;
high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
#endif
/* max_pfn_mapped is updated here */
max_pfn_mapped = init_memory_mapping(0, (max_low_pfn << PAGE_SHIFT));
reserve_initrd();
#ifdef CONFIG_X86_64
vsmp_init();
#endif
dmi_scan_machine();
io_delay_init();
/*
* Parse the ACPI tables for possible boot-time SMP configuration.
*/
acpi_boot_table_init();
#ifdef CONFIG_X86_64
/* Remove active ranges so rediscovery with NUMA-awareness happens */
remove_all_active_ranges();
#endif
#ifdef CONFIG_ACPI_NUMA
/*
* Parse SRAT to discover nodes.
*/
acpi_numa_init();
#endif
initmem_init(0, max_pfn);
#ifdef CONFIG_X86_64
dma32_reserve_bootmem();
#endif
#ifdef CONFIG_ACPI_SLEEP
/*
* Reserve low memory region for sleep support.
*/
acpi_reserve_bootmem();
#endif
#ifdef CONFIG_X86_FIND_SMP_CONFIG
/*
* Find and reserve possible boot-time SMP configuration:
*/
find_smp_config();
#endif
reserve_crashkernel();
reserve_ibft_region();
#ifdef CONFIG_KVM_CLOCK
kvmclock_init();
#endif
#if defined(CONFIG_VMI) && defined(CONFIG_X86_32)
/*
* Must be after max_low_pfn is determined, and before kernel
* pagetables are setup.
*/
vmi_init();
#endif
paging_init();
#ifdef CONFIG_X86_64
map_vsyscall();
#endif
/*
* NOTE: On x86-32, only from this point on, fixmaps are ready for use.
*/
#if defined(CONFIG_PROVIDE_OHCI1394_DMA_INIT) && defined(CONFIG_X86_32)
if (init_ohci1394_dma_early)
init_ohci1394_dma_on_all_controllers();
#endif
#ifdef CONFIG_X86_GENERICARCH
generic_apic_probe();
#endif
early_quirks();
/*
* Read APIC and some other early information from ACPI tables.
*/
acpi_boot_init();
#ifdef CONFIG_X86_64
init_cpu_to_node();
#endif
#if defined(CONFIG_X86_MPPARSE) || defined(CONFIG_X86_VISWS)
/*
* get boot-time SMP configuration:
*/
if (smp_found_config)
get_smp_config();
#endif
#ifdef CONFIG_X86_64
init_apic_mappings();
ioapic_init_mappings();
#else
# if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
if (def_to_bigsmp)
printk(KERN_WARNING "More than 8 CPUs detected and "
"CONFIG_X86_PC cannot handle it.\nUse "
"CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
# endif
#endif
kvm_guest_init();
e820_reserve_resources();
e820_mark_nosave_regions(max_low_pfn);
#ifdef CONFIG_X86_32
request_resource(&iomem_resource, &video_ram_resource);
#endif
reserve_standard_io_resources();
e820_setup_gap();
#ifdef CONFIG_VT
#if defined(CONFIG_VGA_CONSOLE)
if (!efi_enabled || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
conswitchp = &dummy_con;
#endif
#endif
}