arch/loongarch/kernel/efi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * EFI initialization
   4  *
   5  * Author: Jianmin Lv <lvjianmin@loongson.cn>
   6  *         Huacai Chen <chenhuacai@loongson.cn>
   7  *
   8  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
   9  */
  10
  11 #include <linux/acpi.h>
  12 #include <linux/efi.h>
  13 #include <linux/efi-bgrt.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/export.h>
  17 #include <linux/io.h>
  18 #include <linux/kobject.h>
  19 #include <linux/memblock.h>
  20 #include <linux/reboot.h>
  21 #include <linux/uaccess.h>
  22
  23 #include <asm/early_ioremap.h>
  24 #include <asm/efi.h>
  25 #include <asm/loongson.h>
  26
  27 static unsigned long efi_nr_tables;
  28 static unsigned long efi_config_table;
  29
  30 static unsigned long __initdata boot_memmap = EFI_INVALID_TABLE_ADDR;
  31 static unsigned long __initdata fdt_pointer = EFI_INVALID_TABLE_ADDR;
  32
  33 static efi_system_table_t *efi_systab;
  34 static efi_config_table_type_t arch_tables[] __initdata = {
  35         {LINUX_EFI_BOOT_MEMMAP_GUID,    &boot_memmap,   "MEMMAP" },
  36         {DEVICE_TREE_GUID,              &fdt_pointer,   "FDTPTR" },
  37         {},
  38 };
  39
  40 void __init *efi_fdt_pointer(void)
  41 {
  42         if (!efi_systab)
  43                 return NULL;
  44
  45         if (fdt_pointer == EFI_INVALID_TABLE_ADDR)
  46                 return NULL;
  47
  48         return early_memremap_ro(fdt_pointer, SZ_64K);
  49 }
  50
  51 void __init efi_runtime_init(void)
  52 {
  53         if (!efi_enabled(EFI_BOOT) || !efi_systab->runtime)
  54                 return;
  55
  56         if (efi_runtime_disabled()) {
  57                 pr_info("EFI runtime services will be disabled.\n");
  58                 return;
  59         }
  60
  61         efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
  62         efi.runtime_version = (unsigned int)efi.runtime->hdr.revision;
  63
  64         efi_native_runtime_setup();
  65         set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
  66 }
  67
  68 unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
  69
  70 static void __init init_screen_info(void)
  71 {
  72         struct screen_info *si;
  73
  74         if (screen_info_table == EFI_INVALID_TABLE_ADDR)
  75                 return;
  76
  77         si = early_memremap(screen_info_table, sizeof(*si));
  78         if (!si) {
  79                 pr_err("Could not map screen_info config table\n");
  80                 return;
  81         }
  82         screen_info = *si;
  83         memset(si, 0, sizeof(*si));
  84         early_memunmap(si, sizeof(*si));
  85
  86         memblock_reserve(screen_info.lfb_base, screen_info.lfb_size);
  87 }
  88
  89 void __init efi_init(void)
  90 {
  91         int size;
  92         void *config_tables;
  93         struct efi_boot_memmap *tbl;
  94
  95         if (!efi_system_table)
  96                 return;
  97
  98         efi_systab = (efi_system_table_t *)early_memremap_ro(efi_system_table, sizeof(*efi_systab));
  99         if (!efi_systab) {
 100                 pr_err("Can't find EFI system table.\n");
 101                 return;
 102         }
 103
 104         efi_systab_report_header(&efi_systab->hdr, efi_systab->fw_vendor);
 105
 106         set_bit(EFI_64BIT, &efi.flags);
 107         efi_nr_tables    = efi_systab->nr_tables;
 108         efi_config_table = (unsigned long)efi_systab->tables;
 109
 110         size = sizeof(efi_config_table_t);
 111         config_tables = early_memremap(efi_config_table, efi_nr_tables * size);
 112         efi_config_parse_tables(config_tables, efi_systab->nr_tables, arch_tables);
 113         early_memunmap(config_tables, efi_nr_tables * size);
 114
 115         set_bit(EFI_CONFIG_TABLES, &efi.flags);
 116
 117         init_screen_info();
 118
 119         if (boot_memmap == EFI_INVALID_TABLE_ADDR)
 120                 return;
 121
 122         tbl = early_memremap_ro(boot_memmap, sizeof(*tbl));
 123         if (tbl) {
 124                 struct efi_memory_map_data data;
 125
 126                 data.phys_map           = boot_memmap + sizeof(*tbl);
 127                 data.size               = tbl->map_size;
 128                 data.desc_size          = tbl->desc_size;
 129                 data.desc_version       = tbl->desc_ver;
 130
 131                 if (efi_memmap_init_early(&data) < 0)
 132                         panic("Unable to map EFI memory map.\n");
 133
 134                 early_memunmap(tbl, sizeof(*tbl));
 135         }
 136 }