2026-01-29 22:25:33 +08:00

222 lines
5.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* 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>
#include <asm/platform.h>
unsigned long entSuspend;
unsigned long bios_version;
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;
}
static efi_config_table_type_t arch_tables[] __initdata = {
{SMBIOS3_TABLE_GUID, NULL, ""},
{SLEEP_ENTRY_GUID, &entSuspend, "SLEEP ENTRY"},
{BIOS_VERSION_GUID, &bios_version, "BIOS VERSION"},
{},
};
static int __init uefi_init(u64 efi_system_table)
{
efi_char16_t *c16;
efi_config_table_t *config_tables;
efi_system_table_t *systab;
size_t table_size;
char vendor[100] = "unknown";
int i, retval;
systab = early_memremap(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);
/*
* Verify the EFI Table
*/
if (systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) {
pr_err("System table signature incorrect\n");
retval = -EINVAL;
goto out;
}
if ((systab->hdr.revision >> 16) < 2)
pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n",
systab->hdr.revision >> 16,
systab->hdr.revision & 0xffff);
efi.runtime = systab->runtime;
efi.runtime_version = systab->hdr.revision;
/* Show what we know for posterity */
c16 = early_memremap(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",
systab->hdr.revision >> 16,
systab->hdr.revision & 0xffff, vendor);
table_size = sizeof(efi_config_table_64_t) * systab->nr_tables;
config_tables = early_memremap(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,
arch_tables);
early_memunmap(config_tables, table_size);
out:
early_memunmap(systab, sizeof(efi_system_table_t));
if (!bios_version)
retval = -EINVAL;
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:
/*
* 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");
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;
if (sunway_boot_params->efi_systab == 0) {
pr_info("System Table is not exist, disabling EFI.\n");
return;
}
/* Grab UEFI information placed in struct boot_params by stub */
efi_system_table = sunway_boot_params->efi_systab;
if (!efi_system_table)
return;
data.desc_version = sunway_boot_params->efi_memdesc_version;
data.desc_size = sunway_boot_params->efi_memdesc_size;
data.size = sunway_boot_params->efi_memmap_size;
data.phys_map = sunway_boot_params->efi_memmap;
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();
memblock_reserve(sunway_boot_params->efi_memmap & PAGE_MASK,
PAGE_ALIGN(sunway_boot_params->efi_memmap_size +
(sunway_boot_params->efi_memmap & ~PAGE_MASK)));
}