linux/arch/x86/kernel/efi_32.c
Huang, Ying 2215e69d2c x86 boot: use E820 memory map on EFI 32 platform
Because the EFI memory map are converted to e820 memory map in bootloader, the
EFI memory map handling code is removed to clean up.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:19 +01:00

141 lines
3.6 KiB
C

/*
* Extensible Firmware Interface
*
* Based on Extensible Firmware Interface Specification version 1.0
*
* Copyright (C) 1999 VA Linux Systems
* Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
* Copyright (C) 1999-2002 Hewlett-Packard Co.
* David Mosberger-Tang <davidm@hpl.hp.com>
* Stephane Eranian <eranian@hpl.hp.com>
*
* All EFI Runtime Services are not implemented yet as EFI only
* supports physical mode addressing on SoftSDV. This is to be fixed
* in a future version. --drummond 1999-07-20
*
* Implemented EFI runtime services and virtual mode calls. --davidm
*
* Goutham Rao: <goutham.rao@intel.com>
* Skip non-WB memory and ignore empty memory ranges.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/time.h>
#include <linux/spinlock.h>
#include <linux/bootmem.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/efi.h>
#include <linux/kexec.h>
#include <asm/setup.h>
#include <asm/io.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/desc.h>
#include <asm/tlbflush.h>
#define PFX "EFI: "
/*
* To make EFI call EFI runtime service in physical addressing mode we need
* prelog/epilog before/after the invocation to disable interrupt, to
* claim EFI runtime service handler exclusively and to duplicate a memory in
* low memory space say 0 - 3G.
*/
static unsigned long efi_rt_eflags;
static DEFINE_SPINLOCK(efi_rt_lock);
static pgd_t efi_bak_pg_dir_pointer[2];
void efi_call_phys_prelog(void) __acquires(efi_rt_lock)
{
unsigned long cr4;
unsigned long temp;
struct desc_ptr gdt_descr;
spin_lock(&efi_rt_lock);
local_irq_save(efi_rt_eflags);
/*
* If I don't have PSE, I should just duplicate two entries in page
* directory. If I have PSE, I just need to duplicate one entry in
* page directory.
*/
cr4 = read_cr4();
if (cr4 & X86_CR4_PSE) {
efi_bak_pg_dir_pointer[0].pgd =
swapper_pg_dir[pgd_index(0)].pgd;
swapper_pg_dir[0].pgd =
swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
} else {
efi_bak_pg_dir_pointer[0].pgd =
swapper_pg_dir[pgd_index(0)].pgd;
efi_bak_pg_dir_pointer[1].pgd =
swapper_pg_dir[pgd_index(0x400000)].pgd;
swapper_pg_dir[pgd_index(0)].pgd =
swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
temp = PAGE_OFFSET + 0x400000;
swapper_pg_dir[pgd_index(0x400000)].pgd =
swapper_pg_dir[pgd_index(temp)].pgd;
}
/*
* After the lock is released, the original page table is restored.
*/
local_flush_tlb();
gdt_descr.address = __pa(get_cpu_gdt_table(0));
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
}
void efi_call_phys_epilog(void) __releases(efi_rt_lock)
{
unsigned long cr4;
struct desc_ptr gdt_descr;
gdt_descr.address = (unsigned long)get_cpu_gdt_table(0);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
cr4 = read_cr4();
if (cr4 & X86_CR4_PSE) {
swapper_pg_dir[pgd_index(0)].pgd =
efi_bak_pg_dir_pointer[0].pgd;
} else {
swapper_pg_dir[pgd_index(0)].pgd =
efi_bak_pg_dir_pointer[0].pgd;
swapper_pg_dir[pgd_index(0x400000)].pgd =
efi_bak_pg_dir_pointer[1].pgd;
}
/*
* After the lock is released, the original page table is restored.
*/
local_flush_tlb();
local_irq_restore(efi_rt_eflags);
spin_unlock(&efi_rt_lock);
}
/*
* We need to map the EFI memory map again after paging_init().
*/
void __init efi_map_memmap(void)
{
memmap.map = NULL;
memmap.map = bt_ioremap((unsigned long) memmap.phys_map,
(memmap.nr_map * memmap.desc_size));
if (memmap.map == NULL)
printk(KERN_ERR PFX "Could not remap the EFI memmap!\n");
memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
}