136 строки
3.1 KiB
C
136 строки
3.1 KiB
C
/*
|
|
* Extensible Firmware Interface
|
|
*
|
|
* Based on Extensible Firmware Interface Specification version 2.4
|
|
*
|
|
* Copyright (C) 2013, 2014 Linaro Ltd.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
*/
|
|
|
|
#include <linux/efi.h>
|
|
#include <linux/io.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/mm_types.h>
|
|
#include <linux/preempt.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/rwsem.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/efi.h>
|
|
#include <asm/mmu.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
extern u64 efi_system_table;
|
|
|
|
static struct mm_struct efi_mm = {
|
|
.mm_rb = RB_ROOT,
|
|
.mm_users = ATOMIC_INIT(2),
|
|
.mm_count = ATOMIC_INIT(1),
|
|
.mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
|
|
.page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock),
|
|
.mmlist = LIST_HEAD_INIT(efi_mm.mmlist),
|
|
};
|
|
|
|
static bool __init efi_virtmap_init(void)
|
|
{
|
|
efi_memory_desc_t *md;
|
|
|
|
efi_mm.pgd = pgd_alloc(&efi_mm);
|
|
init_new_context(NULL, &efi_mm);
|
|
|
|
for_each_efi_memory_desc(&memmap, md) {
|
|
phys_addr_t phys = md->phys_addr;
|
|
int ret;
|
|
|
|
if (!(md->attribute & EFI_MEMORY_RUNTIME))
|
|
continue;
|
|
if (md->virt_addr == 0)
|
|
return false;
|
|
|
|
ret = efi_create_mapping(&efi_mm, md);
|
|
if (!ret) {
|
|
pr_info(" EFI remap %pa => %p\n",
|
|
&phys, (void *)(unsigned long)md->virt_addr);
|
|
} else {
|
|
pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
|
|
&phys, ret);
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
|
|
* non-early mapping of the UEFI system table and virtual mappings for all
|
|
* EFI_MEMORY_RUNTIME regions.
|
|
*/
|
|
static int __init arm_enable_runtime_services(void)
|
|
{
|
|
u64 mapsize;
|
|
|
|
if (!efi_enabled(EFI_BOOT)) {
|
|
pr_info("EFI services will not be available.\n");
|
|
return 0;
|
|
}
|
|
|
|
if (efi_runtime_disabled()) {
|
|
pr_info("EFI runtime services will be disabled.\n");
|
|
return 0;
|
|
}
|
|
|
|
pr_info("Remapping and enabling EFI services.\n");
|
|
|
|
mapsize = memmap.map_end - memmap.map;
|
|
memmap.map = (__force void *)ioremap_cache(memmap.phys_map,
|
|
mapsize);
|
|
if (!memmap.map) {
|
|
pr_err("Failed to remap EFI memory map\n");
|
|
return -ENOMEM;
|
|
}
|
|
memmap.map_end = memmap.map + mapsize;
|
|
efi.memmap = &memmap;
|
|
|
|
efi.systab = (__force void *)ioremap_cache(efi_system_table,
|
|
sizeof(efi_system_table_t));
|
|
if (!efi.systab) {
|
|
pr_err("Failed to remap EFI System Table\n");
|
|
return -ENOMEM;
|
|
}
|
|
set_bit(EFI_SYSTEM_TABLES, &efi.flags);
|
|
|
|
if (!efi_virtmap_init()) {
|
|
pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Set up runtime services function pointers */
|
|
efi_native_runtime_setup();
|
|
set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
|
|
|
|
efi.runtime_version = efi.systab->hdr.revision;
|
|
|
|
return 0;
|
|
}
|
|
early_initcall(arm_enable_runtime_services);
|
|
|
|
void efi_virtmap_load(void)
|
|
{
|
|
preempt_disable();
|
|
efi_set_pgd(&efi_mm);
|
|
}
|
|
|
|
void efi_virtmap_unload(void)
|
|
{
|
|
efi_set_pgd(current->active_mm);
|
|
preempt_enable();
|
|
}
|