blob: d4987d013080174bda0e462f029c03192897bebb [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Extensible Firmware Interface
*
* Based on Extensible Firmware Interface Specification version 2.4
*
* Copyright (C) 2013 - 2015 Linaro Ltd.
*/
#define pr_fmt(fmt) "efi: " fmt
#include <linux/efi.h>
#include <linux/fwnode.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/mm_types.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_fdt.h>
#include <linux/platform_device.h>
#include <linux/screen_info.h>
#include <asm/efi.h>
unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
static int __init is_memory(efi_memory_desc_t *md)
{
if (md->attribute & (EFI_MEMORY_WB|EFI_MEMORY_WT|EFI_MEMORY_WC))
return 1;
return 0;
}
/*
* Translate a EFI virtual address into a physical address: this is necessary,
* as some data members of the EFI system table are virtually remapped after
* SetVirtualAddressMap() has been called.
*/
static phys_addr_t __init efi_to_phys(unsigned long addr)
{
efi_memory_desc_t *md;
for_each_efi_memory_desc(md) {
if (!(md->attribute & EFI_MEMORY_RUNTIME))
continue;
if (md->virt_addr == 0)
/* no virtual mapping has been installed by the stub */
break;
if (md->virt_addr <= addr &&
(addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT))
return md->phys_addr + addr - md->virt_addr;
}
return addr;
}
extern __weak const efi_config_table_type_t efi_arch_tables[];
/*
* x86 defines its own screen_info and uses it even without EFI,
* everything else can get it from here.
*/
#if !defined(CONFIG_X86) && (defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON))
struct screen_info screen_info __section(".data");
EXPORT_SYMBOL_GPL(screen_info);
#endif
static void __init init_screen_info(void)
{
struct screen_info *si;
if (screen_info_table != EFI_INVALID_TABLE_ADDR) {
si = early_memremap(screen_info_table, sizeof(*si));
if (!si) {
pr_err("Could not map screen_info config table\n");
return;
}
screen_info = *si;
memset(si, 0, sizeof(*si));
early_memunmap(si, sizeof(*si));
if (memblock_is_map_memory(screen_info.lfb_base))
memblock_mark_nomap(screen_info.lfb_base,
screen_info.lfb_size);
if (IS_ENABLED(CONFIG_EFI_EARLYCON))
efi_earlycon_reprobe();
}
}
static int __init uefi_init(u64 efi_system_table)
{
efi_config_table_t *config_tables;
efi_system_table_t *systab;
size_t table_size;
int retval;
systab = early_memremap_ro(efi_system_table, sizeof(efi_system_table_t));
if (systab == NULL) {
pr_warn("Unable to map EFI system table.\n");
return -ENOMEM;
}
set_bit(EFI_BOOT, &efi.flags);
if (IS_ENABLED(CONFIG_64BIT))
set_bit(EFI_64BIT, &efi.flags);
retval = efi_systab_check_header(&systab->hdr);
if (retval)
goto out;
efi.runtime = systab->runtime;
efi.runtime_version = systab->hdr.revision;
efi_systab_report_header(&systab->hdr, efi_to_phys(systab->fw_vendor));
table_size = sizeof(efi_config_table_t) * systab->nr_tables;
config_tables = early_memremap_ro(efi_to_phys(systab->tables),
table_size);
if (config_tables == NULL) {
pr_warn("Unable to map EFI config table array.\n");
retval = -ENOMEM;
goto out;
}
retval = efi_config_parse_tables(config_tables, systab->nr_tables,
efi_arch_tables);
early_memunmap(config_tables, table_size);
out:
early_memunmap(systab, sizeof(efi_system_table_t));
return retval;
}
/*
* Return true for regions that can be used as System RAM.
*/
static __init int is_usable_memory(efi_memory_desc_t *md)
{
switch (md->type) {
case EFI_LOADER_CODE:
case EFI_LOADER_DATA:
case EFI_ACPI_RECLAIM_MEMORY:
case EFI_BOOT_SERVICES_CODE:
case EFI_BOOT_SERVICES_DATA:
case EFI_CONVENTIONAL_MEMORY:
case EFI_PERSISTENT_MEMORY:
/*
* Special purpose memory is 'soft reserved', which means it
* is set aside initially, but can be hotplugged back in or
* be assigned to the dax driver after boot.
*/
if (efi_soft_reserve_enabled() &&
(md->attribute & EFI_MEMORY_SP))
return false;
/*
* According to the spec, these regions are no longer reserved
* after calling ExitBootServices(). However, we can only use
* them as System RAM if they can be mapped writeback cacheable.
*/
return (md->attribute & EFI_MEMORY_WB);
default:
break;
}
return false;
}
static __init void reserve_regions(void)
{
efi_memory_desc_t *md;
u64 paddr, npages, size;
if (efi_enabled(EFI_DBG))
pr_info("Processing EFI memory map:\n");
/*
* Discard memblocks discovered so far: if there are any at this
* point, they originate from memory nodes in the DT, and UEFI
* uses its own memory map instead.
*/
memblock_dump_all();
memblock_remove(0, PHYS_ADDR_MAX);
for_each_efi_memory_desc(md) {
paddr = md->phys_addr;
npages = md->num_pages;
if (efi_enabled(EFI_DBG)) {
char buf[64];
pr_info(" 0x%012llx-0x%012llx %s\n",
paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
efi_md_typeattr_format(buf, sizeof(buf), md));
}
memrange_efi_to_native(&paddr, &npages);
size = npages << PAGE_SHIFT;
if (is_memory(md)) {
early_init_dt_add_memory_arch(paddr, size);
if (!is_usable_memory(md))
memblock_mark_nomap(paddr, size);
/* keep ACPI reclaim memory intact for kexec etc. */
if (md->type == EFI_ACPI_RECLAIM_MEMORY)
memblock_reserve(paddr, size);
}
}
}
void __init efi_init(void)
{
struct efi_memory_map_data data;
u64 efi_system_table;
/* Grab UEFI information placed in FDT by stub */
efi_system_table = efi_get_fdt_params(&data);
if (!efi_system_table)
return;
if (efi_memmap_init_early(&data) < 0) {
/*
* If we are booting via UEFI, the UEFI memory map is the only
* description of memory we have, so there is little point in
* proceeding if we cannot access it.
*/
panic("Unable to map EFI memory map.\n");
}
WARN(efi.memmap.desc_version != 1,
"Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
efi.memmap.desc_version);
if (uefi_init(efi_system_table) < 0) {
efi_memmap_unmap();
return;
}
reserve_regions();
/*
* For memblock manipulation, the cap should come after the memblock_add().
* And now, memblock is fully populated, it is time to do capping.
*/
early_init_dt_check_for_usable_mem_range();
efi_find_mirror();
efi_esrt_init();
efi_mokvar_table_init();
memblock_reserve(data.phys_map & PAGE_MASK,
PAGE_ALIGN(data.size + (data.phys_map & ~PAGE_MASK)));
if (IS_ENABLED(CONFIG_X86) ||
IS_ENABLED(CONFIG_SYSFB) ||
IS_ENABLED(CONFIG_EFI_EARLYCON))
init_screen_info();
}