/*
* Extensible Firmware Interface
*
* Based on Extensible Firmware Interface Specification version 2.4
*
* Copyright (C) 2013 - 2015 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.
*
*/
#define pr_fmt(fmt) "efi: " fmt
#include <linux/efi.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/mm_types.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/platform_device.h>
#include <linux/screen_info.h>
#include <asm/efi.h>
u64 efi_system_table;
static int __init is_normal_ram(efi_memory_desc_t *md)
{
if (md->attribute & EFI_MEMORY_WB)
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 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;
}
static __initdata unsigned long screen_info_table = EFI_INVALID_TABLE_ADDR;
static __initdata efi_config_table_type_t arch_tables[] = {
{LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID, NULL, &screen_info_table},
{NULL_GUID, NULL, NULL}
};
static void __init init_screen_info(void)
{
struct screen_info *si;
if (screen_info_table != EFI_INVALID_TABLE_ADDR) {
si = early_memremap_ro(screen_info_table, sizeof(*si));
if (!si) {
pr_err("Could not map screen_info config table\n");
return;
}
screen_info = *si;
early_memunmap(si, sizeof(*si));
/* dummycon on ARM needs non-zero values for columns/lines */
screen_info.orig_video_cols = 80;
screen_info.orig_video_lines = 25;
}
if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI &&
memblock_is_map_memory(screen_info.lfb_base))
memblock_mark_nomap(screen_info.lfb_base, screen_info.lfb_size);
}
static int __init uefi_init(void)
{
efi_char16_t *c16;
void *config_tables;
size_t table_size;
char vendor[100] = "unknown";
int i, retval;
efi.systab = early_memremap_ro(efi_system_table,
sizeof(efi_system_table_t));
if (efi.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);
/*
* Verify the EFI Table
*/
if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
pr_err("System table signature incorrect\n");
retval = -EINVAL;
goto out;
}
if ((efi.systab->hdr.revision >> 16) < 2)
pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n",
efi.systab->hdr.revision >> 16,
efi.systab->hdr.revision & 0xffff);
efi.runtime_version = efi.systab->hdr.revision;
/* Show what we know for posterity */
c16 = early_memremap_ro(efi_to_phys(efi.systab->fw_vendor),
sizeof(vendor) * sizeof(efi_char16_t));
if (c16) {
for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
vendor[i] = c16[i];
vendor[i] = '\0';
early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t));
}
pr_info("EFI v%u.%.02u by %s\n",
efi.systab->hdr.revision >> 16,
efi.systab->hdr.revision & 0xffff, vendor);
table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
config_tables = early_memremap_ro(efi_to_phys(efi.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, efi.systab->nr_tables,
sizeof(efi_config_table_t),
arch_tables);
early_memunmap(config_tables, table_size);
out:
early_memunmap(efi.systab, sizeof(efi_system_table_t));
return retval;
}
/*
* Return true for RAM regions we want to permanently reserve.
*/
static __init int is_reserve_region(efi_memory_desc_t *md)
{
switch (md->type) {
case EFI_LOADER_CODE:
case EFI_LOADER_DATA:
case EFI_BOOT_SERVICES_CODE:
case EFI_BOOT_SERVICES_DATA:
case EFI_CONVENTIONAL_MEMORY:
case EFI_PERSISTENT_MEMORY:
return 0;
default:
break;
}
return is_normal_ram(md);
}
static __init void reserve_regions(void)
{
efi_memory_desc_t *md;
u64 paddr, npages, size;
int resv;
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_t)ULLONG_MAX);
for_each_efi_memory_desc(md) {
paddr = md->phys_addr;
npages = md->num_pages;
resv = is_reserve_region(md);
if (efi_enabled(EFI_DBG)) {
char buf[64];
pr_info(" 0x%012llx-0x%012llx %s%s\n",
paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1,
efi_md_typeattr_format(buf, sizeof(buf), md),
resv ? "*" : "");
}
memrange_efi_to_native(&paddr, &npages);
size = npages << PAGE_SHIFT;
if (is_normal_ram(md))
early_init_dt_add_memory_arch(paddr, size);
if (resv)
memblock_mark_nomap(paddr, size);
}
set_bit(EFI_MEMMAP, &efi.flags);
}
void __init efi_init(void)
{
struct efi_fdt_params params;
/* Grab UEFI information placed in FDT by stub */
if (!efi_get_fdt_params(¶ms))
return;
efi_system_table = params.system_table;
efi.memmap.phys_map = params.mmap;
efi.memmap.map = early_memremap_ro(params.mmap, params.mmap_size);
if (efi.memmap.map == NULL) {
/*
* 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");
}
efi.memmap.map_end = efi.memmap.map + params.mmap_size;
efi.memmap.desc_size = params.desc_size;
efi.memmap.desc_version = params.desc_ver;
WARN(efi.memmap.desc_version != 1,
"Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
efi.memmap.desc_version);
if (uefi_init() < 0)
return;
reserve_regions();
efi_memattr_init();
early_memunmap(efi.memmap.map, params.mmap_size);
memblock_reserve(params.mmap & PAGE_MASK,
PAGE_ALIGN(params.mmap_size +
(params.mmap & ~PAGE_MASK)));
init_screen_info();
}
static int __init register_gop_device(void)
{
void *pd;
if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
return 0;
pd = platform_device_register_data(NULL, "efi-framebuffer", 0,
&screen_info, sizeof(screen_info));
return PTR_ERR_OR_ZERO(pd);
}
subsys_initcall(register_gop_device);
